INTRODUCTION
Portuguese adventures was first to Goa and to the Malabar Coast in Kerala by the Spaniards and to other centres in India. It was planted particularly along the shore and has become naturalized throughout the West coast (Kerala, Karnataka, Goa and Ratnagiri tract of Maharashtra); East Coast (Tamil Nadu, Andhra Pradesh, Orissa, West Bengal) and Andaman Islands. At present, both Malabar and South Kanara contribute maximum cashew production in India.
SPECIES OF ANACARDIUM
It is reported that as many as 20 species of Anacardium Linn, are known to exist within Central and South America; among which Anacardium occidentale (Cashew nut) is the only species which has been introduced outside the new world and commercially grown in the tropical countries.
TAXONOMY AND NOMENCLATURE
Cashew is an English name of the fruit tree known botanically as Anacardium occidentale, belongs to the family Anacardiaceae of which the mango is the most important species. The family Anacardiaceae consists of sixty-four genera in which many plants are of horticultural importance viz: cashew, mango (Mangifera indica), amra (Spondias mangifera), Chironji (Buchanania latifolia), Pistachio (Pistacia cera) etc.
The importance of cashew
Cashew is held with great esteem in many customs and cultures. Its value can be estimated from a question that appeared on the household census in Mozambique that asked whether the house owned any cashew trees.
Cashew is known by many names. In Mozambique, the Maconde tribe refer to it as the "Devil's Nut". It is offered at wedding ceremonies as a token of fertility and is considered by many to have aphrodisiac properties.
The cashew industry ranks third in the world production of edible nuts with world production in 2000 at about 2 million tonnes of nuts-in-shell and an estimated value in excess of US$2 billion. India and Brazil are the major cashew exporters, with 60 percent and 31 percent respectively of world market share. The major importers are the United States (55 percent), the Netherlands (ten percent), Germany (seven percent), Japan (five percent) and the United Kingdom (five percent).
Cashew kernels are ranked as either the second or third most expensive nut traded in the United States. Macadamia nuts are priced higher and pecan nuts can be more costly, if the harvest is poor. Cashew nuts have a well established market in the United States with a great variety of uses. Retail prices range from about US$4 to 11 per pound (US$9 to 23 per kg) depending on the size of nut and the packaging.
The extensive market connections of exporters from Brazil and India make it difficult for the smaller exporters to make gains in the United States market.
INDIAN CASHEW - THE GOVERNMENT INITIATIVES
The Horticulture sector, in general, has gained considerable importance in the Indian agrarian sector due to its potential for diversification, employment generations and achieving higher returns per unit area.
Cashew is one of the prominent horticultural crops which has been contributing to the Indian economy in a sustained manner. It is a crop which has been a source of income to small and marginal farmers of the country. The Cashew Industry in India, has a history of about a Century which dates back to the first quarter of the 20th Century. From a meager quantity of 50 tonnes baggage in the most primitive paper cover enclosures sent to USA in the year 1921, it has steadily grown over a period of time and has attained an export level of 1.00 lakh tonnes of cashew kernels, valued at Rs 2,500 crores. The credit to this admirable achievement in cashew export sector goes to the untiring efforts of our industrial entrepreneurs.
About a dozen countries are competiting in cashew sector. Compared to the productivity of these countries, India is in a better place. Brazil and Vietnam which have entered recently in global business of cashew, their productivity level have not made any impact over our situation. The scientifically proven high-yielding cultivars developed in the country can therefore, help us to have an edge over other countries. We have still scope for area coverage and replacement.
In our endeavour for augmenting cashew production, role of cashew corporations cannot be seen in isolation. Though in terms of percentage these areas are less, in absolute terms, nearly a lakh of hectare comes under their purview which are not managed as per scientific norms. Directors of various Corporations have taken effective steps for converting their plantations by way of varietal upgradation into an economic productive plantation.
The traditional system of processing needs modernization. The Cashew Export Promotion Council of India has taken steps in this regard which is a noteworthy attempt. Utilization of by-products, particularly of cashew apple and cashewnut shell liquid (CNSL) remains a grey area still unexplored to a greater extent.
The concept of horticultural development at large, has now been grouped under the macro management system, where the state administration has the liberty to prioritize their agricultural sector through work plans under macro management scheme. The cashew-producing states should avail this opportunity and provide adequate impetus for its development in their state.
In contrast to our earlier ways and means for promotion of cashew, now greater stress is being given towards the regionalization of various technologies.
The recommendations need to be widened involving a large number of weaker sections of the society in different zones. The potential of North-Eastern region is another area for exploitation. If we can consolidate our efforts to such non-traditional areas, cashew production scenario will have a better prospect in coming years.
In the age of globalization of trade, attaining competitiveness in our produce and products alone can help us to remain steadfast in the global trade of cashew. Qualitative improvements in material production suited to market preferences are the integral part of this system. Increasing productivity, improving quality and supply to the world market at competitive rates on a sustained basis are some of the measures needed to withstand the impact of WTO agreement.
CASHEW DEVELOPMENT IN INDIA
There was no systematic and scientific cultural outlook for cultivation of cashew until the beginning of 20th century. The Forest Departments in most of the states introduced cashew as a part of afforestation to upgrade and maintain their denuded areas and prevent soil erosion and also to prevent high velocity of winds along sea coasts. Such plantation development was primitive and non-scientific, which continued till the fag end of 60's of 20th century. Economic value of cashew was realized by the administrative circles and agrarian sector from mid 60's only. Though, not much scientific input was there, a little bit of systematization was involved in post 60's. Real horticultural outlook for economical and commercial exploitation took place only during the last 2 decades. Many private entrepreneurs involved in its cultivation with Governmental support. Prior to this period, some states encouraged cashew cultivation by distribution of indiscript seeds and seedlings.
CENTRALLY-AIDED PROGRAMMES
As a third step of optimizing the scientific input for better plantation development, a centrally aided programme to multiply and distribute cashew air-layers was initiated in mid 70's. However, air-layers in field had its own premature death, due to inadequate survivals, for want of deeply penetrating tap roots to anchor the crop in soil against high-velocity winds in monsoon and prolonged drought in the immediately succeeding summer after planting. This was the period, when a national outlook on cashew research with the inception of All India Coordinated Cashew Improvement Project under ICAR, involving local research centres under several SAUs, came into its action. This marked a significant turn in cashew research. Germplasm evaluation for selection and hybridization towards development of branded varieties of high-yielding genotypes, standardization of propagation technique, nutritional management, combating the incidences of several pests, all came under the fold of research on a national outlook and regional specificity.
This formed the fourth step under centrally aided programme in streamlining planting material situation. The 80's of 20th century was indeed an era of silverline for cashew development in India. The first half of this period witnessed the launch of an internationally- aided project (World Bank-aided Multi State Cashew Project). Massive area coverage with elite seed took place. Research activity attained a better boost in terms of financial help, technical work and infrastructural build-up. More than 60,000 ha area came under cashew in both public and private sectors. This project was one of the milestones in the scenario of Indian Cashew Development. Nearly 4.5 million dollars (nearly Rs 45 million) was the financial inflow. But the project was conceived at a disadvantageous situation for there were no proven varieties and a standardized multiplication technique. Though better quality seeds have gone into the field, the genetic diversity has worked against the aspirations and motives of this project over a period of time, these plantations also became just an addition to the already existing cashew plantations in the
country, but with very little edge over indiscreet seedling plantations developed prior to this period. The last decennium of the Century along with golden era celebration of the Indian Independence; the research, almost completing its 25 years of activity also attained its silver jubilation, when for the first time in India, nearly 25 branded varieties with economic advantages conforming to higher yield potential and international standards of consumer preferences came out lifting its curtain.
This period comprised Eighth and Ninth Five-Year Plan, for Agricultural System Development in India. The financial allocation for cashew development increased 5 - 6 times from a mere Rs 8 crores of the Seventh Plan. The Eighth Plan (1992-97) witnessed an allocation of Rs 45 crores for cashew development. Golden lines started glittering in all the activities of cashew development during this period.
INTEGRATED DEVELOPMENT
With the release of 25 high-yielding varieties, scion bank complexes were started to stock the clones of all high -yielding varieties in all regions according to regional specificity The multiplication technique of softwood grafting was standardized and it gained popularity among all cultivating centres. Soil nutritional needs and manipulation according to needs of all varieties and regions of cultivation were standardized. Water relationship of cashew, microirrigation system and moisture conservation practices were important technologies developed by research system for large-scale adoption. Seedling plantation was totally abandoned and prohibited through administrative instructions. Along with the research and developmental agencies, involvement of private entrepreneurs in planting material multiplication, also was encouraged. Regional nurseries in both public and private sectors came up in large measure and area expansion was clonally supported in India for the first time under cashew development. During Eighth Plan, more than a lakh of ha perhaps the largest area under clones in the world came under clonal cashew areas in India by way of new plantations and replantings. For the production build-up, 48 regional nurseries were established. As far as scientific knowledge of farming sector is concerned, all the technological advancements were quite new for them, and the transfer of technology thereby became an integral part of development.
AREA, PRODUCTION AND PRODUCTIVITY IN INDIA
The production situation of cashew in India is given in Annexure I and summarized in Table-I.
Production of cashew in India takes place in Kerala, Karnataka, Goa, Maharashtra, Tamil Nadu, Andhra Pradesh, Orissa, West Bengal, interior tracts of Chattisgarh and North-eastern region. In 1965-66' about 2.4 lakhs ha area was under cashew with a production of 1 Iakh tonnes and productivity of 400 kg/ha.
The technological support and administrative and financial encouragement became more conspicuous for cashew development in India during Eighth plan. Before this cashew development was going on with limited resources. The experience gained in the past has given more strength and confidence among state implementing agencies to handle a substantial higher outlay. The varietal wealth of cashew developed by the research front changed the developmental scenario in a drastic manner. The standardized technique of softwood grafting added further impetus to generate adequate clones of the high-yielding varieties in development of qualitative plantations.
AGRO-ECOLOGICAL REGIONS AND CLASSIFICATION OF CASHEW
Cashew is a very important foreign-exchange earing horticultural crop of our country. The pioneering research centres in the country at Bapatla, Vridhachalam, Kottarakkara, Vengurla, Vittal, Ullal, Madakkathara and Puttur were instrumental in assembling valuable cashew germplasm. With the establishment of Central Plantation Crop' Research Institute at Kasaragod (Kerala) in l970 and All India Coordinated Spices and Cashew nut Improvement Project in 1971 by ICAR, cashew research was further strenthened in the country. The implementation of World Bank aided Multi State Cashew Project(MSCP) in 1982 in 4 states, establishment of National Research Centre for Cahew at Puttur ( Karnataka) and also an independent All India Coordinated Research Project on Cashew (AICRP on Cashew) in 1986 gave cashew research much needed impetus. With the efforts of different cashew research centres in the country, a total of 36 cashew varieties have been released for commercial cultivation.
Release of these varieties has definitely shown the impact on increase in yield. During 1990, total cashew production in country was 2.95 lakh tonne from 5.32 lakh ha. During 1999-2000, for the first time, production crossed 5.2 lakh tonnes, from 6.01 lakh ha due to tremendous increase in production from Maharashtra as well as from Andhra Pradesh, where the productivity has crossed 1 tonne/ ha . Varietal recommendation is mainly based on the results of All India Coordinated Research Project on Cashew Centers under the SAUs and a few multilocation trials. Most of varieties released by
The areas Dharmapuri, North Arcot, Chengalpattu, Villupuram, South Arcot, Tiruchirapalli, Thanjavur and Pudukkotta fall under second region, while Tirunelveli area where considerable development has taken place in cashew are with medium AWC and LGP is only 90 - 120 days . Further, normally the fruiting takes place in the month of March to May in this area, where the water deficiency is 139mm and 90mm while in May it is 124 mm. This could be one of the reasons for poor performance of some of the varieties planted here. However, it is suggested that varieties which can flower very early with supplementary irrigation only come up in this particular area. Further this is also as indicated earlier that semi and dry eco subregion is not very ideal compared to subhumid and hot moist subhumid and per humid areas.
MORPHOLOGY AND CHARACTERISTICS OF GROWTH AND DEVELOPMENT OF CASHEW TREE
The Cashew is a polygamous, andro-monoceious, evergreen perennial tree with darkish-green leathery foliage, crooked branches, very irregular crown and un-attractive appearance. It is somewhat compact low-growing plant (upto 5-6 m height), spreads over the foliage in a radius of around 8 m, forms mostly umbrella-shaped canopy and provides a good shade. The trunk is normally rough, semi-hard and exudes a yellowing gum which darkens on sunlight.
FLORAL BIOLOGY
The cashew trees are polygamous, andro-monoecious; both staminate (male) and hermaphrodite flowers are produced on the same inflorescence.
The Inflorescence
The cashew inflorescence is an open panicle, which is usually borne at the end of current seasons short terminal branches, for this reason, the majority of the flowers are to be found on the periphery of the tree on new shoots, similar to mango. The inflorescence may be either conical, pyramidal or irregular in shape. It was observed that 45% of the panicles are conical, 40% irregular and 15% pyramidal. The average length of panicle and the average spread at the basal
Flowers
The structure of the flower is similar in both staminate and hermaphrodite flowers; however the hermaphrodite flowers are slightly larger than staminate flowers. The stamen of staminate flower, is always larger than that of hermaphrodite flower.
The flowers are small (6-8 mm) pentamerous, aromatic, upright, light-greenish at the time of opening, later turning into creamy white in colour with pink stripes. In an open flower the separated tips of the petals turn downward parallel to the peduncle, thus assuming a cup like shape.
Flushing period
The flushing occurs in young plantations throughout the year, while in the adult trees, two periods can be distinguished according to the seasonal periodicity of the climate, October- January and March-May; however, 84% of the shoots produce flowers between December-February.
Flowering season
After flushing of new shoots, panicles bearing with male and perfect flowers are produced only during one of the major flushing periods. The male flowers are produced throughout the blooming period of the tree, while 80% of the complete flowers appear between the second half of January and the first fortnight of March in most of the cashew growing areas. The maximum flowering is observed in the months of March-May; even though early flowering (December-January) is noticed in Deccan region (Goa and Ratnagiri belt). The peak period of flowering in costal areas is from November-December to February-March; while at high altitude, late flowering is normally observed, mostly due to reduction in temperature.
Flower-bud development
The time taken for complete development and opening of flower- bud from its visible initiation is approximately 17 days. The time from the first appearance of the inflorescence to the opening of first flowers is about 5 to 6 weeks.
Mode of Pollination
Cashew is an entomophilous and highly cross pollinated crop as the fruit-set in only 48% in natural open pollination. It was reported that insects such as ants and files visit the flowers and transfer the sticky pollen to the stigmatic surface. It is reported that in Tanzania, the fly population of the cashew plantations increases markedly during the cashew flowering season. It is thus believed that these insects must play a considerable part in pollination. Naturally, no other insects except black and red ant, are seen to visit the flowers frequently. However, the heavy scent of flowers indicates that insects play an important role in pollination.
However, wind seems to be the pre-dominate agency for pollination. The pollination is caused by wind. The high proportion of male to perfect flowers suggests that the tree may be basically wind-pollinated.
Pollen viability and germination in artificial media
The viability of pollen grains is found to be around 94 per cent. However, in artificial medium, the highest germination obtained was only 36.2% in 30 per cent sucrose solution at 29° C room temperature. The percentage of viable pollen varies from 80-90% on the basis of the results of an acetocarmine stainability test. Pollen grains collected 15 minutes after dehiscence are more viable than fresh ones. Fresh pollen Incubated for 12 h at 25° C showed normal growth and at 20° C in a moist atmosphere did not loose. Viability after 50 hours of storage, and at 7° C remained viable up to 11 months.
The cashew flower, once fertilized, undergoes radical transformations, the zygote remains dormant for some time and later on produces an embryo. Within 6 weeks, the embryo is completely filled with the seed coat. The ovule becomes a seed, the ovary changes into a pericarp which surrounds and protects the seed; finally the seed plus pericarp form the fruit within 12 weeks after fertilization; while the receptacle, in turn, swells and changes into the false fruit (cashew apple).
FRUIT SET AND FRUIT DROP
Even though a large number of male flowers are produced in each tree, a high percentage of perfect flowers remain unpollinated. The failure of pollen germination on the stigma is the main cause of low percentage of setting. The other factors are the failure of gynoecia to develop properly, thrips damage and the reduction in viability of small quantities of pollen caused by low humidity and high temperature.
There is a high percentage of immature fruit drop in cashew caused by insect-pests or other factors. It was observed that fruit drop during every stages of development due to physiological reasons. Others reported 55 % fruit drop at the mustard stage and 22% at the Peanut stage. It is reported that out of the fertilized fruits
IMPROVED PRODUCTIVITY OF CASHEW THROUGH SOIL AND NUTRIENT MANAGEMENT
Cashew is grown all over the tropics and part of subtropics. It is welI -adapted to a wide variety of soils from coastal sands to degraded laterites worst soils, which are not suited to other crops, are normally allotted for cashew. Cashew grows well in soils, which are very poor in nutrients. In Sri Lanka and the Philippines, it is grown in alluvial soils. Cashew comes up well even in volcanic soils in Indonesia, Fiji and the Philippines. It can survive slightly saline waters but not brakish waters. Cashew is not suitable in heavy clays, watarlogged conditions and ill-drained soils. It is grown abundantly in loose sandy soils particularly in South India, East Africa and Brazil. In Karnataka and Kerala, it grows well in poor laterite soils. Cashew prefers well-drained acrated sandy loam with adequate moisture. Coastal plains and plateau are very good for cashew cultivation.
ROOT DISTRIBUTION PATTERN
Cashew being a perennial tree, remains continuously in soil over a long period of time. It has deep and spreading root system. Root distribution pattern of cashew depends on the age of tree, type of planting material, soil environment, level of nutrition, irrigation etc. Majority of feeding roots normally reside in surface layer of soil.
Tap roots of three-and-a-half year-old extend upto 3.2 m . They also found that lateral spread of root varies with age of trees. 85% thick roots and 45% fine roots occur within 15 cm surface soil layer.
RESPONSE TO NUTRIENTS
Information regarding response of cashew to fertilizers is briefly indicated below.
Nitrogen: Nitrogen is kingpin of nutrients. It is absorbed by plants in the form of nitrate and ammonium ions and as urea. It is essential for the formation of proteins and it is an integral part of chlorophyll . An adequate supply of N enhances vegetative growth. When N becomes deficient, plant growth is stunted and leaves turn yellow. The yellowing or chlorosis usually appears first on lower leaves and spread to upper leaves later. Severe N shortage results in death of leaves.
The response of cachew to applied N is tremendous.lt is the element that is absorbed by cashew in largest quantity. The growth and development of cashew are very much influenced by N application. Increase in cashew yield due to N application as reported. The response of cashew to N application is universal, except in very rich soils.
TIME OF FERTILIZER APPLICATION
For getting maximum efficiency of applied nutrients, it is necessary to apply fertilizers at physiological phase of the tree at which the internal nutrient demand is highest . Biologists studied root activity of cashew in relation to phenological phases, employing 32p soil injection technique, in laterite soils of Kerala .Highest root activity and peak absorption of 32p , were noticed in flushing and early flowering stage, which extended from September to December. It is suggested that the onset of this phase is most appropriate time for fertilizer application in a cashew orchard. Root activity was
EFFECT OF WEATHER PARAMETERS ON CASHEW PRODUCTION
Cashew exists across the west and east coasts of India from south to north, lying between 09°N and 23°N latitude. Though it grows beyond 23°N of latitude in north-eastern states of India, the area under cashew is less and its contribution in terms of production is relatively low. The cashew tract lies within the tropical belt of India as a tropical crop as the low night temperature during the reproductive phase (December- February) may not be conducive in subtropics. Its cultivation is given prime importance from the last one to one-and-a-half decade due to its economic value. Still, it remains as a neglected crop when majority of cashew-going areas are examined. It is more so across the west coast except in Maharashtra to some extent. Across the west coast at lower latitudes, cashew is spread from coastal belt to hill slopes, extending up to l,000 m (AMSL). The states covered across the west coast are Kerala, Karnataka, Goa and Maharashtra, whereas, cashew is mostly grown in plains across the east coast (Tamil Nadu, Andhra Pradesh, Orissa and West Bengal).
Effect of latitude and altitude on flowering
An attempt was made to express the importance of latitude, longitude and alitude in the distribution and rate of development of plains by means of a "Bio climatic law". It may be stated as 'A bio tic event in North America will, in general, show a lag of four days for each degree of latitude, five degree of longitude and 400 feet of altitude, northward, eastward and upward in spring and early summer". In mango, the India Meteorological Department also established that there as a delay in flowering from South to North of India, which generally followed Hopkins' Bio climatic law.
The law stated by Hopkins is sound in biotic events of cashew in tropical monsoon climates under better crop management in rainfed situations, provided the genotype and rainfall distributions are uniform. However, there is a difference in number of days delayed in cashew flowering at each degree of North latitude while the effect of altitude on time of cashew flowering is similar as stated by Hopkins. In tropical monsoon climates, there appeared to be a delay of 6 days in cashew flowering at every 1° of North latitude and for 100m of altitude, the delay in cashew flowering was 3 days. The variation in duration of reproductive phase of cashew with latitude and altitude could be explained due to variation in surface air temperature viz,. day maximum and night minimum temperatures.
Rainfall and sunshine versus budbreak
The budbreak of cashew varies between September and December depending upon the variety. It is seen immediately after wet spell. It may not be subjected to soil moisture stress. A moderate soil moisture stress (less than 50% of Ima)could be seen only from mid December, indicating that soil moisture stress begins only after budbreak occurs. As there is no dearth of soil moisture and budbreak of cashew varies depending upon genotype and rainfall distribution, it is likely that budbreak may be more dependent on atmospheric variables rather than soil moisture under better crop management situations.
A close examination on daily distribution of rainfall from August to December during 1995, 1996, 1997 and 1998 indicated that early cessation of rains and intermittent dry spells during August and September 1995 might have led to early budbreak in cashew during that year. In contrast, it was not during 1998-99. which led to delay in budbreak of cashew. However, delay in budbreak of late variety was distinct as seen in MDK 2 during 1997-98. It was due to the distribution of rainfall during November and December.
Heat units and cashew yield
There was a significant variation in heat unit requirement of cashew depending upon genotype. Early variety, Ank 1, required only 1953 day° C for reproductive phase (25% budbreak to 75% harvest) while it was 2.483 day0 C in late season type like Mdk 2. The heat unit requirement of mid-season type as intermediary (2.245 day0 C). It was interesting to note that early season types require less heat units while late season types require more beat units and the beat unit requirement of the mid season types are intermediary.
The heat units versus cashew yields of test varieties showed that there was no definite relationship existed between them as negative relationship was seen in 50% of the cases and positive in other 50% of cases. This was mainly attributed to the incidence of a pest complex, which is not uncommon during flowering season of cashew across West coast. This is a severe menace and effects the duration of crop and cashew production as the case during 1995-99.
DISEASES OF CASHEW
Compared to the number of pests infesting cashew, the serious diseases are very few only and the magnitude of loss due to diseases is also very low. No virus disease has so far been reported on cashew and the economic importance of fungal diseases is only quite meagre.
In the tropics, the fight against maladies of phyto-pathological nature would be of preventive measures, aimed at allowing the plant to develop in suitable conditions like proper drainage of the ground for seedlings, right spacing between plants, ensuring normal circulation of air and giving adequate sunlight above ground for the grown up trees. Further, selection of varieties showing greater natural resistance to certain disease, combined with their vegetative propagation, are some measures to protect health of the cashew trees. However, when more areas are covered with improper phytosanitation, the loss due to disease is likely to increase.
DISEASES OF SEEDLINGS
The most destructive diseases affecting cashew seedlings are damping of, seedling blight and root rot. The seedlings are more susceptible to these diseases which occur in nurseries, where drainage conditions are poor. Hence, heavy seeds may be used and soaked in acetone for 2 hours to get quick and uniform germination of vigorous seedlings and thus to combat the potential threats of the dreadful seedling diseases.
Symptoms
Early symptoms of the disease consist of reddish-brown shiny, water-soaked lesions, followed by resinous exudation on the affected parts. Affected inflorescences have a blackening of the floral peduncles and affected flowers turn black, wither and fall off. The lesions grow longitudinally, resulting in ultimate killing of shoots.
Tender leaves when affected, become crumpled, cover with tiny necrotic patches at the edges and the tip. Nuts and apples become shrivelled, decayed or dried out. The nuts show small necrotic spots on their epicarp; while apples turn black and mummified. The fungus enters the fruit through the floral sitgma. The symptoms vary according to the organs attacked.
Spread of the Disease
This pathogen continues its growth on the dead parts of the host tissues after killing during unfavourable period. When the atmospheric humidity is high and cashew plants put-forth new flushes, the pathogen becomes active and infects the tender parts, producing abundant conidia. Those are dispersed by air currents and by rain splash and spread all over the plantation. Light also enhances sporulation of the fungus and temperature at 30° C is most favourable. The diseases develops under warm and humid conditions, it becomes virulent when heavy rainfall coincides with the flowering season of cashew. Besides inflorescence, it also attacks tender leaves, twigs, immature nuts and apples.
PROPAGATION - LAYRING, BUDDING AND GRAFTING
It is thus found that monocrotophus is the most effective insecticide to control tea mosquito and minor pests in all cashew growing States in India, except Kerala where endosulfan spray was found effective.
Propagation means multiplication of plants either sexual (through seeds) or asexual (vegetative) methods. Cashew can be multiplied using any one of these methods.
In the sexual methods, plants are raised by sowing seeds either in the nursery and then transplanting of seedlings or directly sowing in the field at appropriate distance. Propagation by asexual method means vegetative multiplication of the selected parents trees by self radiation (layers) or by grafting.
Cashew, being a highly cross-pollinated crop, it produces heterogenous plants when propagated by seeds and those seedling manifest variation which are found not uniform in growth, yielding ability, nut characters and quality parameters due to segregations; while vegetatively propagated plants conserve all the desirable characters of the elite mother plant, keeping in the same genetic make up and thus produce a new plant true to type. These plants also start bearing early, give relatively more uniform yield with good quality produce.
SEXUAL (SEED) PROPAGATION
The most common method of propagating cashew is by seeds which is still in practice commercially, in spite of various methods of vegetative propagation have been standardized. Selection of nuts from superior mother trees from planting is likely to give better results than use of unselected seeds collected from a commercial orchard. However, the poor performance of seedling progenies may be attributed to high heterogeneity of the population and poor genetic make-up.
Specific Gravity of Nut
Selected seed-nuts of high specific gravity (1.0-1.05) give excellent germination and vigorous growth of seedlings. Usually, medium-sized nuts which sink in water easily, are preferable to either very small or large nuts. Small nuts produce weak seedlings, while large nuts having low specific gravity due to air pockets between kernel and shell, float on water and hence are not suitable for seed purpose. It is reported that about 95 per cent of the heavy nuts germinate within two weeks, while the water-floating ones could give around 60 per cent germination.
The weight and volume of high density seed nuts are positively correlated with height and number of leaves produced by seedlings, thus showing close association between nut characters and seedling characters.
Seed Storage
The collected seed-nuts are sun-dried for 2-3 days, graded and stored for a short-period. In cashew, the viability of seeds deteriorated rapidly, even 4 to 5 months after storage which is reflected in progressive decrease in percentage germination of seed-nuts, as the period of storage increased. Seed viability under metallic bin storage was studied for a period of 11 months and the percentage of germination was noted.
The results obtained clearly indicated that cashew nut cannot be stored more than 5 months for seed purpose. However, if the seed-nuts are kept in closed tins, the seed viability may remain for about a year.
ASEXUAL (VEGETATIVE) PROPAGATION
Plants raised from seeds show variation in morphological and economic characters, showing unpredicted performance, and hence the only means can be adopted is the vegetative propagation of the selected outstanding mother trees. The vegetatively propagated trees are more precocious (start to production within 2 years); their subsequent cropping is much better than seedling trees. They are enable to reproduce clones faithfully from the desirable types and raise progenies true-to type with homogeneous material.
However, the practice of vegetative propagation is still confined to a limited application, because of high cost of production and longer distant transplantation. It was also thought earlier that the preparation of vegetative planting material consumes more time and labour and thus considered unsuitable for large scale production. That conception is being removed through recent advancement of easy techniques for vegetative propagation, reduction in cost of graft production and use of small vegetative part (scion). Thus, the cashew growers are gradually encouraged to plant with clonal materials rather seedlings in a larger area.
LAYERING TECHNIQUE
Bark removal
Layering is done by stripping away a ring of bark about 2-3 cm wide just below a bud, at a point about 25 cm from the tip of the selected shoot of previous season's growth. The cambium layer is completely removed by scraping the exposed wood of the shoot, so as to prevent re-union of both the cut- ends and to induce root formation on the upper side of the ringed portion.
Application of Growth Regulator
During vegetative propagation, the endogenous auxins are naturally utilized by plant parts for causing root formation; but we found that external application of plant growth substances like IBA (Indole Butyric Acid) and IAA (Indole Acetic Acid) in proper concentration (100 to 200 ppm) can improve further effectiveness of such micro-rooting. We also found that the application of a commercial product. SERADIX A (IBA) at 200 ppm makes for better chances of quick and successful number of rooting of air-layers; while others obtained 84.6% success in cashew layers by treating with IBA 800 ppm as paste at the upper end of the 0.5 cm wide ring made, as compared to 46.3% in the control. It is thus preferable to apply IBA for getting successful air-layers with sufficient root formation at least 10 days earlier than the conventional practice.
Nursery Management
After 10-12 days, healing will take place and the sprouting of the terminal bud will be emerged. Then the Cap should he removed gently and the sprouted graft is shifted to open place in the nursery and to be watered as and when required. Bordeaux mixture (1%) spray may be given at 2-3 weeks intervals as a prophylactic measure to minimize the fungal infection. The ribbon from the union place should be removed after two months of operation. New sporuted buds emerged from any portion of the root stock should be removed at frequent intervals and the grafts to be shifted frequently to prevent them from stricking roots into the ground. Partial shade is needed during summer months which can be done by erecting pandal and covering with plaited coconut leaves.
CULTIVATION
The cashew tree grows with a minimum of attention and is easily cultivated. It is usually found from sea level to an altitude of 1 000 metres (3 000 feet), in regions with annual rainfall as low as 500 mm (20 inches) and as high as 3750 mm (150 inches). For maximum productivity, good soil and adequate moisture are essential. Optimum conditions include an annual rainfall of at least 889 mm (35 inches) and not more than 3048 mm (120 inches). The tree has an extensive root system, which helps it to tolerate a wide range of moisture levels and soil types, but commercial production is only advisable in well-drained, sandy loam or red soils. The cashew tree can flourish in the sand of open beaches, but it grows poorly in heavy clay or limestone.
Pit Making/Filling
The pits may be dug by hand or specialized machine. The usual method is to make planting holes of about 50 x 50 x 50 cm. While digging, the surface and lower layers of earth are kept separately and in re-filling, the fertile top-soil mixed with compost or cow dung are placed at the bottom of the whole and the inert layer on the surface. The digging of pits may be done during April, so as to allow the pits to weather till the end of May; and the pits are re-filled just before the break of the monsoon.
Spacing and Plant Population
Proper distance between plants has to be maintained, keeping in view ecological characteristics and physiological requirements of cashew crop. The spacing must be chosen with soil-water availability, since the density of planting always be in proportion to the quantity of soil-water present around the root zone. In long dry season, the water supply will be inadequate, when trees are planted too close. However, young immature trees need less water and hence can be grown much closer than older trees.
Effect of Spacing
The effect of spacing (plant density) on nut yield; the relationship between spacing and water stress and canopy covered at early years of growth, has been recorded in Tanzania and also in India.
These results show that during fourth year, trees growing in the lowest density yielding more than twice; but in terms of yield/ ha, the highest density plantation produced almost three times; however, the yield/tree and yield/ha started declining in the high density planting during the fifth year of production, indicating thereby to thin out from the fourth year. The high initial yield, rapid shading of land and reducing the cost of weeding are the advantages of high density planting.
Supplementary Irrigation
As such, cashew is a rain-fed crop. However, supplementary irrigation during flowering/fruit season with water-saving technique, using minimum available water resources, can increase the production substantially.
An observation trial conducted at National Research Centre for Cashew, indicated that supplementary irrigation @ 200 litres per tree once in 15 days from November to March (10 irrigations) resulted in direct effect on fruit retention (44%) and in a significant increase in yield (7.3 kg/tree) as compared to no irrigation (3.54 kg/tree), indicating definite response to irrigation.
NUTRIENTS
The gap between the requirement of raw cashew nuts and actual production calls for urgent steps, not only for the extension of the area but also enhancement of productivity of existing cashew plantation by appropriate measures such as fertilizer application, plant protection and good management. Since there is only limited areas available for extension of cashew plantation, an increase in productivity is the only answer to meet the crisis in India's cashew industry.
Manuring in cashew is not a regular practice in the existing gardens in India, even though adequate fertilizer application might be the quickest method and is one of the viable means for increasing the productivity of cashew. However, majority of the existing cashew growers do not apply fertilizer on cashew, except by the cashew or forest Department of most of the cashew growing states who own cashew plantations.
It is probably true that cashew can draw the nutrients from large volume of soil due to its extensive root system and the small growers seldom manure this crop.
Response to Major Nutrients
Results from package programmes implemented in early years show that cashew yield increases following regular application of 250 g N, 150 g P205 and 150g K2O/tree. The results from mini-kit trials initiated by the Indian Council of Agricultural Research provided further proof for the profitability of regular fertilizer application on 15-year old trees , and within 3 years after fertilization, the same tree which yielded about 1.1 kg/tree, averaged nearly 4 kg/tree, ensuring the fertilizer application of cashew is profitable.
PLANNING FOR IMPROVED PRODUCTIVITY THROUGH EFFICIENT WATER MANAGEMENT
Cashew has well adapted to the Indian climatic conditions, particularly in coastal belt of the country . It is suitable for cultivation in the regions having annual rainfall between 600 and 700mm, upto an altitude of 700 m above mean sea level and temperatures not below 20°C. Cashew can withstand extreme rainfall conditions ranging from 200 to 4000 mm per annum. It is a sun-loving tree and does not tolerate excessive shade. It does not tolerate very high temperatures above 45° C during fruit setting and developmental stage. There has been a steady increase in the productivity of cashewnut. The year 1997-98 was marked with adverse climatic conditions during fruit setting stage which resulted in 21 % reduction in yield. The current level of productivity of cashewnut is about 760 kg/ha. an increase of about 22 % as compared to 1992-93.
Over the years cashew has emerged as a high income-generating export-oriented comodity. In 1999-2000, the area under cashew was about 6.8 lakh ha producing about 5.2 Lakh tonnes of cashewnut. Despite the increase in area and production over the past several years, the current production is able to supply only about 50% of the demand of raw cashew nut by processing industry. In India, cashew is cultivated mostly as a rainfed crop by small and marginal farmers. In West Coast,cashew is largely grown on hill slopes where topsoil has been eroded almost completely leading to exposure of subsoil.
PRINCIPLES OF IRRIGATION AND WATER MANAGEMENT
Water is a Life-sustaining resource, which is essential for sustaining of living organisms on the earth. Although water is a renewable resource it is getting deteriorated quality as well as quantity. Availability of adequate, timely and assured irrigation is a critical input for agricultural production; which is equally true for horticultural crops including cashew.
Soil - Plant - Water Relationships
Soil-plant-water relationship deals with the properties of soil and plants which affect the movement retention and use of water. Soil act as a reservoir where water is stored to be used by the plants. Water is essential for the growth of the crop. For an efficient utilization of water it is important to know the physical properties of soil in relation to water.
Physical Properties of Soil
Soils comprise minerals, organic matter, chemical compounds (solid phase), soil moisture (liquid phase) and soil air (gaseous phase). The size and shape of the soil particles give rise to pore space which are filled with water and air in varying proportion. In addition, the soil usually contain numerous living organisms such as bacteria, fungi, algae, protozoa, insects and small worms which directly or indirectly affect the soil structure and plant growth. The most important soil properties which influence irrigation are its infiltration characteristics and water-holding capacity. Other properties like soil texture, soil structure, capillary conductivity, soil profile conditions and depth of watertable are also important for managing irrigation water.
Advanced Methods of Irrigation
The advanced methods of irrigation include sprinkler and drip that could he introduced for all types of crops depending upon the soil, slope, water source, farmers' capacity etc. It has been established that the yields of the crops are enhanced in addition to saving of water and improvement in quality of produce with these methods.
ORGANIC FARMING IN CASHEW
Cashew, leads the edible nuts in international trade with 20% of the market. From tropical America, its natural habitat, it spread throughout the tropics by early Portuguese and Spanish travellers. However, cashew nut gained importance in international trade only in early 1920s. Today, it is cultivated mainly in India, Mozambique, Tanzania, Brazil and Kenya. India is a leading producer, processor and exporter of cashew kernels in the world. The importance of cashew for the Indian economy has been due to its role as a foreign-exchange earner and generating employment to over 3 lakh persons, 95% of them being women.
Method
Clean the mushrooms and cashew nuts in hot water. Grate the coconut and extract the coconut milk from three-quarters of the coconut. Boil the cashew nuts and mushrooms. Grind the remaining coconut, red chillies, coriander, turmeric and cumin into a fine paste. Slice the onion, ginger, garlic and slit the green chillies. Heat the oil and add the mustard and curry leaves. When the seeds start to pop, add the ground spices and sliced ingredients. Cook until the onions are soft. Add the cooked cashew nuts and mushrooms, lime juice and salt. Simmer for 10 minutes. Add the coconut milk and simmer for 5 minutes.
Cashew apple vinegar
Cashew apple juice can also be used for preparing vinegar, raising the Brix to 12° by adding sugar. The juice is pasteurized cooled and inoculated with a pure strain of yeast, Saccharomyces cervisiae or brewer's yeast for alcoholic fermentation. Vinegar fermentation could be done by 'slow process' as well as by quick process'. In the slow process, it is kept as such for 4 to 5 days, mixed with one-third mother vinegar, while in the quick process it is prepared by passing the alcoholic ferment mixed with mother vinegar through a column of about 1.5 m height filled with corn cobs.
TRADITIONAL METHODS OF CASHEW PROCESSING
Cashew processing in Africa
Traditionally, much of the raw Eastern African production has been shipped to India for processing and re-exported as kernels. Manual processing, such as that practised in India, tends to give higher yields of whole kernels than the mechanized methods in use in Africa and Brazil. This practice decreased toward the end of the 1970s and early 1980s when production in the exporting countries declined.
Cashew processing in Guinea Bissau
Most of cashews produced in Guinea are exported to India for processing. There is, however, a cashew processing centre in Quinhamel at which some local processing takes place. Raw cashew nuts are boiled in a large cauldron for 25 minutes, then sun-dried for 48 hours. This makes it easier to separate the nut from the shell. Shells are removed from individual cashews using a foot-powered shelling machine.
Those African countries which experienced a decline in their cashew production capacities may now be in a position to revive the industry, particularly at the small-scale. Following the Indian example of small-scale manual processing, rather than continuing with the old concept of large plants that are unable to operate efficiently, will be the most appropriate way forward and will provide opportunities for small-scale processors.
Traditional processing in India
The traditional practice in the south Arcot region of India was to spread the nuts out on flat rocks in the sun, to allow them to dry until the shell became brittle. The kernel could then be removed from the shell by striking the nut with a wooden batten to split the shell along the natural line of cleavage. The cashew kernel was removed
Open pan roasting
Open pan roasting is used by traditional cashew processors in India. This roasting technique is very simple with minimal equipment requirements. It however requires skill and judgement in order to prevent the nuts from burning.
The roasting pan is an open circular mild steel dish, measuring 600 to 675 mm (2 to 2.5 feet) in diameter, supported over an open fire. Between 1 and 1.5 kg of raw nuts are placed on to the heated pan at a time. The nuts are heated on the pan, with constant stirring, in order to prevent burning. As the nuts heat up, the CNSL is exuded onto the pan and eventually ignites, producing clouds of thick black smoke. After heating and burning for about two minutes (judged by experience) the pan is dowsed in water and the nuts are thrown off and allowed to cool, during which the shells become brittle and can be readily removed from the nut.
Traditional processing in Sri Lanka
Cleaned raw nuts are spread in a single layer on the ground under bright sunlight for six to seven hours a day, over a two to three day period, in order to attain the correct stage of dryness. Partially dried nuts are covered with polythene overnight. A trained processor can determine the correct stage of dryness by shaking together a few dried nuts in the palm of his hands, to give the correct rattling noise.
Processors sit on the ground and shell the nuts by beating with a mallet two or three times on the same spot, until the shell cracks.
CASHEW PROCESSING OPERATIONS
General processing
Cashew processing methods have improved considerably over the years. Difficulties in shelling cashew nuts are due to the irregular shape of the nut, the tough leathery outer shell and the CNSL within the shell that must not be allowed to contaminate the kernel during its removal from the shell. An early method used to remove the CNSL in cashew producing countries was to burn the raw nuts for a short period in order to burn the shells and the CNSL without affecting the taste or appearance of the kernel. This was a delicate operation requiring an experienced processor to gauge the length of time required for burning. Kernels produced using this method are only suitable for either home consumption or for the local market.
The most economic features of processing are the ratio of kernels to whole nuts obtained and the percentage of whole kernels obtained. Kernel yields usually vary between 22 and 24 percent of the total weight of raw material processed. The percentage of whole kernels at the end of processing varies between 55 and 85 percent depending upon the processing method and factory management. In general, 65 percent may be considered a satisfactory result.
The main objective of processing is to remove the valuable cashew kernel from the shell with as little damage as possible. Whole kernels command a higher price than do broken pieces. Pale, ivory coloured or white kernels are preferable to coloured or burnt ones. The CNSL has to be removed during the process, without either contaminating the cashew kernels or burning the hand of the processor. The processor must therefore, finely tune the process in order to achieve the best quality kernels.
Rehumidification
Prior to packing the kernels, it is necessary to ensure that their moisture content is increased from three percent up to around five percent. This makes the kernels less fragile, thus lessening the risk of breakage during transport. In humid climates, the kernels may absorb enough moisture during peeling and grading to make a further rehumidification process unnecessary.
The final moisture content is critical since, moisture contents in excess of six percent, favour mould growth. Moisture content of five percent is optimal. Many processors have facilities for adjusting the moisture content.
The moisture content of the cashews can be increased by transferring them to conditioning rooms which are completely closed rooms, in which trays of cashew kernels are placed overnight to absorb moisture from the surrounding air. Under low humidity conditions, the floor is sprayed with water prior to closing the door. Under high relative humidity conditions, it may not be necessary to add water to the floor. Steam is sometimes used for humidifying the kernels. Saturated steam is allowed into the conditioning room. The amount of steam to be injected is determined on basis of personal experience.
CASHEW BYPRODUCTS
CNSL, a by-product of the cashew industry is a unique monomeric source for making various polymeric products. Cashew Shell Liquid was first investigated by Stadeler in 1947, who isolated two distinct compounds, anacardic acid and 'cardonol' from the either extracted material. CNSL which is most valuable byproduct of cashew processing industry is an important raw material in the pain, chemical, brake linings, clutch facings, plastic and wood industries. The liquid is extremely dense, brownish, sticky bitter caustic with smokes that irritate and gives off choking fumes.
PRODUCTS OF CNSL DERIVATIVES RUBBER LIKE ELASTICITY PRODUCTS
The present method relates to compositions of matter which are reaction products of the oil found in the shell surrounding the kernel of the cashew nut. The product relates further to reaction products of cashew nut shell oil with glycerine or with other polyhydric alcohols or homologs of glycerine, reaction products which have properties common to various kinds and conditions of rubber. These products are suitable for uses to which rubber is put and for use in the arts generally. These products for a great many purposes may properly be termed artificial rubber.
In the preparation of these reaction products various proportions of glycerine and cashew nut shell oil or distillates there of are used to produce various products. Reaction is best produced by heat or by some thickening reagent such as sulphuric acid, or some other acid or by ammonia or the like. When heat is used for bringing about the reaction the two ingredients may be mixed and then heated, or one or both of them may be heated before they are brought together. The oil may be heated to temperatures up to its flash point for the purpose of driving out water before mixing with the glycerine. The reaction products vary from a jelly comparable to rubber latex to thick substances having characteristics of congealed rubber.
ELECTRICAL INSULATING MATERIAL
The materials of the present method are suitable for their electrical insulating qualities, for example, to hold an electrical conductor in place against vibrations in an electrical machine, and the products are suitable for use as protective coatings and impregnations, for molded and mechanical parts having a degree of strength.
An example of a method for making and applying an impregnating compound for electric coils is now given. Cashew nut shell liquid is brought up to a temperature of about 600° F and then permitted to cool, and as it cools, about one per cent of manganese resinate is added at 450° F. 'When the liquid reaches room tempera¬ture about three per cent of hexamine is added and the mixture is heated to 195° F to dissolve the hexamine. Coils to be impregnated are heated for about two hours at about 225° F and then placed in an autoclave and the air withdrawn therefrom, the suction being held for about one-half hour after maximum vacuum is obtained. The above prepared impregnating liquid is then charged into the autoclave without breaking the vacuum and the vacuum held for another half hour after charging with the impregnating liquid. From the time the liquid is charged into the autoclave the temperature therein is raised above room temperature to make the impregnating liquid thin but is kept below 160° F, so that said liquid does not set prematurely. The temperature used on a coil with paper between layers was kept around 125° F. At the end of the second half-hour period, that is one-half hour after the impregnating liquid is charged into the autoclave, the vacuum is released and pressure is applied of about 60 to 80 pounds for about one-half hour, to drive the liquid into the coils, the temperature being unchanged.
POLYMERIZATION OF CASHEW NUT SHELL LIQUID
It is well known that cashew nut shell liquid in the natural condition contain elements or radicals in combinations which cause a vesicant action on the human skin when they come in contact with the same. The vesicant effect, although it is temporary and leaves no harmful after effect, is highly disagreeable and uncomfortable in some cases and is usually accompanied by swelling and itching.
We have discovered that the poisonous or vesicating juices, such as cashew nut shell liquid, contain sulphur, apparently in a sulphide combination, and we have further discovered that the combinations which cause the poisoning or vesicant action are altered or destroyed when the juice, such as cashew nut shell is treated to modify, to destroy or to remove therefrom the natural sulphide content. As a result the irritating or vesicating action on the human skin is eliminated. Various methods and steps for the treatment of the juice to secure this modification are described below.
Cashew nut shell liquid is freed of its naturally occurring sulphide content by heating with a small quantity of a reagent which will react with the sulphide sulphur or with the radical in which said sulphur occurs.
POLYMERIZED ETHER OF CASHEW NUT SHELL LIQUID
Three thousand pounds of cashew nut shell liquid and about 1060 pounds of primary amyl chloride are placed in a tank having a steam jacket; a circulating pipe line loop from the bottom thereof, through a pump and then back to the upper part of said tank; and a pressure tight over. About four hundred and fifty pounds of sodium hydroxide are dissolved in about two hundred and sixty gallons of water and the solution added to the ingredients in the tank.
The cover is then closed and tightened and the materials in the tank, by means of said pump, are looped through said pipe line for thorough mixing. By means of said steam jacket, the temperature is brought up to about 325° F, and maintained there for about seven hours, the pressure in the tank accordingly being at 100 to 110 lbs. At the end of this time the steam is cut off the water jacket, the pump is stopped and the tank is left to cool over night at which time the temperature has dropped to about 250° F, to 275° and the pressure to about 40 lbs, and the water solution of sodium chloride and any unreacted sodium hydroxide has settled to the bottom of the tank.
COMMERCIAL EXPLOITATION OF CASHEW APPLES
Nature has given plenty of food yet several nations are suffering from poverty. It is strange phenomena that most nutritious cashew apple is getting wasted in the developing countries like India whose nutritional problems are considerable and varied. As technologists see, there could be equal amount economics if not more and better appeal and nutrition in cashew apples compared with its nuts, because cashew apple weighs 8 times more than its nut.
Cashew Pulp Products
Further usable cashew pulp itself stored for later use with natural preservatives, mixed pickles with right type of well tested and accepted spices and condiments should be used and wide publicity is required. Products like halwa, toffees and candies should be encouraged with the use of pulp at larger scale. Garnessing with dry fruit mixtures including cashew nuts adds taste and makes these products more attractive and marketable.
Dehydrated Cashew Apple Powder
Dehydrated cashew apple powder with and without juice can be used in various value-added products. Several recipes have been prepared with the use of 10 - 30 cashew apple powder as listed below. They all have been tested for acceptability shelf-life of over 3 months.
EVALUATION OF COPPERISED CASHEW NUT SHELL LIQUID AND NEEM OIL AS WOOD PRESERVATIVES
Wood being ligno-cellulolytic material is liable to degradation due to microbial agencies and termites causing significant losses. Since the supply of wood is limited, it is necessary to protect the wood in service from biological deterioration. From time immemorial, attempts were made by many workers to impart durability by treating the wood with natural and synthetic chemicals. The conventional wood preservatives although found to be very effective against wood destroying organisms, are said to cause environmental pollution and a few of them are hazardous to animals and human beings. Over the past few decades, there has been substantial global awareness to develop eco-friendly wood preservatives and those, which do not cause any ill effect on the health of mammals. There is a continuous search for different methods of bio-control methods for wood preservation.
MULTIFUNCTIONAL ADDITIVES FROM CASHEW NUT SHELL LIQUID
Cashewnut shell liquid (CNSL) occurs as a reddish brown viscous liquid in the soft honeycomb structure of the shell of cashewnut, a plantation product obtained from the cashew tree, Anacardium Occidentale L. Native to Brazil, the tree grows in the coastal areas of Asia & Africa. Cashewnut attached to cashew apple is grey colored, kidney shaped and 2.5-4 cm long. The shell is about 0.3 cm thick, having a soft leathery outer skin and a thin hard inner skin. Between these skins is the honeycomb structure containing the phenolic material popularly called CNSL. Inside the shell is the kernel wrapped in a thin brown skin, known as the testa.
The nut thus consists of the kernel (20-25%), the shell liquid (20-25%) and the testa (2%), the rest being the shell. CNSL, extracted with low boiling petroleum ether, contains about 90% anacardic acid and about 10% cardol. CNSL, on distillation, gives the pale yellow phenolic derivatives, which are a mixture of biodegradable unsaturated m-alkylphenols, including cardanol. Catalytic hydrogenation of these phenols gives a white waxy material, predominantly rich in tetrahydroanacardol.
CNSL and its derivatives have been known for producing high temperature phenolic resins and friction elements. Friction lining production from CNSL is also reported. Likewise, it is also known to form different types of friction materials, mainly for use in brake lining system of automobiles and coating resins from CNSL.
VOLATILE NUT AROMA AND FLAVOUR COMPOSITIONS
Gases containing volatile aroma constituents are evolved during one or more stages of processing beverages such as coffee, tea, and cocoa. These volatile aroma gases may be recovered and used in a variety of food products. There are also various methods known for collecting cocoa aroma gases. The vapor is condensed by water or a cooled surface, and the aroma compounds are extracted with a lipid or lipid/solvent blend.
The nut aroma frost particles dislodged from the cakes in the filters fall into a collector at the bottom of the recovery zone and are removed either periodically or on a continuous basis. For example, conventional means, such as a rotary valve, a screw conveyor, an endless belt, and the like, may be provided at the bottom of the recovery zone for the removal of the dislodged nut aroma frost particles from the recovery zone on a continuous basis. Alternatively, an insulated collector may be removably secured to the bottom of the recovery zone below the filters, with the dislodged nut aroma frost particles falling into the collector for periodic recovery of the nut aroma frost particles. In one example the nut aroma frost particles are collected and mixed into a carrier, for example, with a ribbon blender or other suitable mixing device.
The recovered nut aroma frost particles is typically combined with a carrier after it is recovered. Suitable carriers include, but are not limited to, vegetable oils, tropical oils, medium chain triglycerides, propylene glycol, glycerol, cocoa butter, water, and other acceptable food grade solvents. The compositions advantageously contain most or all of the same volatile components present in the original nut itselF, The recovered nut aroma frost particles provide a unique and improved natural nut aroma and flavor composition suitable for addition to various food products.
Some suitable applications for the nut aroma frost particles are beverages (e.g., coffee or creamers), culinary food products (e.g., cookie dough or cake mixes), confectionery food products (e.g., chocolate compounds and coatings), ice cream, and ice cream coatings. The nut aroma and flavor compositions, once recovered according to the invention, can be added to foodstuffs by any method available to one of ordinary skill in the art.
PREPARATION OF HYDROPHOBICALLY MODIFIED POLY (ACRYLIC ACID) [PAA]
One of the exciting developments in the area of high technology in the recent past concerns hydrophobically modified polymers (HMPs) which are able to self associate in aqueous media and form reversible networks with spectacular viscoelastic properties such as enhanced viscosification efficiency, shear thickening property, shear and salt stability. Therefore, they find extensive applications in enhanced oil recovery, cosmetic lotions, paints, coatings, food additives and pharmaceuticals. These polymers consist of a hydrophilic backbone with a small number of hydrophobic groups dispersed along the chain or terminally situated on the chain. There are two ways to incorporate the hydrophobic moities in the water-soluble polymer i.e. the direct copolymerization of hydrophobic monomers with water-soluble monomers or the post modification method using water-soluble polymers.
Various molecular architectures such as random, graft, block and hydrophobically end-capped polymers have been envisaged in designing hydrophobically modified polymers. Although, there are fast expanding academic studies on associating polymers, their industrial development has not really taken place and only a small number of polymers are commercially available. Therefore, there is a need to develop newer HMPs for specific end applications.
The non-solvent used to precipitate the HMP may be methanol, ethanol, isopropanol. The hydrophobic modification is preferably carried out in the temperature range of 50-80° C.
HEAT-CURABLE EPROXY RESIN COMPOSITION
High-quality adhesives are increasingly used in manufacture of both vehicles and mounted parts or machinery and equipment, either instead of or in combination with conventional joining methods such as riveting and punching or welding. This results in advantages and new options for manufacturing, for example manufacture of composite and hybrid materials, or greater freedom in designing components. For use in vehicle manufacture, adhesives must have good adhesion to all substrates used, in particular electrogalvanized, hot-dip galvanized, and subsequently phosphatized sheet steel, lubricated sheet steel, as well as various types of aluminum. These good adhesion properties must also be maintained in particular after aging (alternating climate, salt spray bath, etc.) with no major loss in quality. If the adhesives are used as bodyshell adhesives, then the wash resistance of this adhesive is of considerable importance in order to assure process reliability at the manufacturer's facilities.
Wash resistance can be achieved with or without pregelling. To achieve sufficient wash resistance, the adhesive can be pasty and pregelled in a bodyshell oven within a short time or via induction heating of the parts to be joined.
Bodyshell adhesives must be cured under conventional baking conditions, ideally for 30 minutes at 180° C, Furthermore, they must also be stable up to about 220° C, Other requirements for such a cured adhesive or the bond are that operational reliability is ensured both at high temperatures up to about 85° C, and at low temperatures down to about "40° C, Since these adhesives are structural adhesives and thus these adhesives bond structural parts, high strength of the adhesive is of utmost importance.
Conventional epoxy adhesives are distinguished by high mechanical strength, in particular high tensile strength and high tensile shear strength. When the bond is subjected to impact loading, however, conventional epoxy adhesives are usually too brittle; and so under crash conditions, when both high tensile and high peel stresses occur, they are far from able to meet the requirements of the automobile industry in particular. They also have insufficient strengths at high temperatures and in particular at low temperatures.
Various approaches have been suggested to reduce the brittleness of epoxy adhesives under impact loading. Essentially two methods have been suggested in the literature for improving the impact strength of epoxy adhesives. First, the goal can be achieved by addition of at least partially crosslinked high molecular weight compounds such as latexes of core/shell polymers or other flexibilizing polymers and copolymers. Secondly, some increase in strength can also be achieved by introducing soft segments, e.g., by appropriate modification of the epoxy components.
It is also known that epoxy resins can be flexibilized with elastomers such as synthetic rubbers and their derivatives. The major effect in this case is based on the only partial miscibility of epoxy resins and the corresponding derivatized synthetic rubbers, where as a result heterodisperse phases are formed during the manufacturing process that have an effect comparable to the effect of core/shell polymers. Establishment of this superstructure depends on both the quantitative composition and on process control during the cure process. In the literature known to the person skilled in the art, carboxyl-terminated poly butadiene/acry lonitrile copolymers, which are reacted with epoxy resins, are described as particularly preferred starting compounds for this flexibilizing method.
NUTRITIONAL SUPPLEMENT COMPOSITIONS
Antioxidants are compounds that protect cells against the damaging effects of reactive oxygen species. An imbalance between antioxidants and reactive oxygen species results in oxidative stress, leading to cellular damage and many chronic health problems, such as cancer; atherosclerosis; myocardial infarction; arthritis; immune diseases, inflammation, lupus, and scleroderma; neurodegenerative diseases such as Alzheimer's Disease and Parkinson's Disease; acquired immune deficiency syndrome (AIDS); cataracts; ischemic injury; skin wrinkling; and generalized aging. For example, the oxidation of low-density lipoprotein (LDL) has been recognized to play an important role in atherosclerosis. LDL oxidation can be induced by macrophages and can also be catalyzed by metal ions like copper. Macrophages recognize and engulf oxidized LDL, a process that leads to the formation of atherosclerotic plaques in the arterial wall.
Due to the fact that oxidative damage is implicated in many disease processes, and laboratory research on flavonoids and other antioxidants suggests that they are useful in the prevention and treatment of a number of these disorders, there exists a general need to improve the quality of food ingested in the human body and to fortify various antioxidative mechanisms in the body. In view of the foregoing, it will be appreciated that providing a nutritional supplement drink comprising herbal extracts rich in antioxidants and other nutrients will provide greater health benefits to consumers.
DESCRIPTIONS
In one aspect the present process relates to methods for preparing an nutritional supplement composition, comprising the steps of; (1) providing a volume of a carrier liquid; (2) providing a flower distillate component; (3) providing an herbal extract component, for example, an antioxidant or other nutrient containing herb; and (4) admixing the herbal extract, and the flower distillate with the liquid carrier, and wherein the nutritional supplement composition optionally comprises an additional ingredient selected from the group consisting of a nutrient, for example, a mineral, a vitamin, a lipid, an oil; a protein, an amino acid, a nucleic acid or combination thereof; a flavoring agent; a preservative; a coloring agent; a second carrier agent; and combinations thereof. In any of the preferred examples, the carrier agent comprises water, oil, alcohol or a combination.
HYDROPHOBIC POLYOLS OF LOW VISCOSITY
Prior-art solvent-free two-component (2K) coating systems divide essentially into epoxy resin (2K EP) systems and polyurethane (2K PU) systems.
Coatings based on 2K EP systems combine good mechanical strength with high resistance to solvents and chemicals. Additionally they are distinguished by very good substrate adhesion. A distinct disadvantage is their poor elasticity, particularly at low temperatures. This brittleness results in poor crack bridging by the coating, so that an attack may take place here on the substrate. An additional disadvantage is the very low resistance to organic acids. This is a problem above all for applications in the food sector, since in that sector organic acids are often released as waste products.
A balanced combination of hardness and elasticity, on the other hand, is the outstanding property of the 2K PU coatings and the greatest advantage over 2K EP coatings. With similar solvent and chemical resistances, moreover, the resistance to organic acids of 2K PU coatings is substantially better than that of 2K EP coatings.
For environmental reasons coating compositions ought to be solvent free, particularly in the case of high-build applications, such as floor coatings, for example. This means that the inherent viscosity of the binder component ought to be low.
In the case of high-build applications on the basis of 2K PU systems there is a risk of bubbles forming through the formation of CO2 as a consequence of the water-isocyanate reaction. Therefore it is important that the raw materials exhibit very low water absorption, so that such coatings can be applied without bubbles even under damp conditions.
PREPARATION OF FLAVOUR OR FRAGRANCE MICROCAPSULES
The present process relates to the perfume and flavour industry. It relates more particularly to a coacervation process for the preparation of microcapsules encapsulating a hydrophobic flavor or fragrance ingredient or composition, the process being characterized by the use of a novel and advantageous hardening agent containing a plant extract rich in phenolic compounds.
Encapsulation is a term easily used by the food, flavour and fragrance industry. The processes employed for encapsula-tion may include dehydration techniques such as spray-drying or drum drying, spray chilling, extrusion, mechanical coating or coacervation.
Coacervation, also called aqueous phase separation, is a very well known technique for encapsulating hydrophobic liquids. A coacervation process allows to provide oil-containing microscopic capsules, the encapsulating material being a gelled hydrophilic colloid that is impervious to the oil and deposited evenly and densely about the oil as nucleus. The encapsulating colloid material is a protein which may be complexed with another colloid having an opposite electric charge.
The coacervation process essentially involves an aqueous protein solution which is manipulated by changing the physico-chemical environment (dilution and/or adjustment of pH) to result in phase separation of the protein from the solution to varying degrees depending on the molecular weight of the protein, its iso electric point and compatibility with solvents.
A coacervation process can be "simple" or "complex". The former designation is employed when a single protein is used to form a capsule wall as phase separation is taking place. The latter term designates the use of a second oppositely charged non-protein polymer to bring about the phase separation. Complex coacervation method is widely practiced in commercial processes.
The protein is an essential element of the process, as it will go under gelation in order to form a wall around the oil droplets, before being hardened. Use of proteins for encapsulation is limited but versatile, primarily due to their gelling and solubility characteristics. These characteristics are manipulated by changes in temperature, pH, addition of a second polyelectrolyte solution, a second solvent or even ionizing salt solution.
SILANE-MODIFIED PHENOLIC RESINS
Rubber articles, such as tires, belts and hoses, normally use reinforcing materials such as steel, polyester, nylon, aramid and rayon in the form of fibers, cords or fabrics. In the case of radial tire production, steel cords are often used as the reinforcing material. Steel cords for tires, in general, are coated with a layer of brass to promote adhesion between the steel cords and rubber compounds. In order to improve the adhesion between rubber and steel cords, the use of a cobalt salt, such as cobalt naphthenate, and/or a phenolic adhesive composition comprising a methylene acceptor and methylene donor in the compound formulations are in current practice. The copper and zinc present in the brass coating react with sulfur to form a bonding layer, comprising sulphides of copper and zinc, between the steel cord and rubber.
