1. Technology for Production of Insecticides of Plant Origin at Rural Level
Materials and Methods
Results and Discussion
Use of leaf Bits
Use of Leaf Extracts
Impregnation of Bags with Kernel Extract
Surface Treatment of Bins
Vapour Effect of Extract/Oil
Technology for Rural Level

2. Neem seed cake as a Source of Pests Control Chemicals
Methods and Materials
Results and Discussion

3. Neem oil as Possible Biorational Insecticide
Materials and Methods
Results and Discussion

4. Improving the Productivity of Neem Trees
Distribution
Agroclamatic Adaptability
Establishment and Growth
Production and uses
Non-wood Products
Environmental Safety
Problems of Neem Production and Utilization
Propagation of Neem
Variation in Germplasm
Silvicultural Practices to Improve Productivity
Establishment of neem
Fruiting
Seed Collection and Processing
Promotion of Neem Production
Packaging of Silvicultural Practices
Popularising the Use of Neem Products
Marketing of the Produce

5. Vegetative Propagation of Azadirachta indica A. Juss.
Materials and Methods
Mist Propagation
Micropropagation
Results
Mist Propagation
Micropropagation
Discussion

6. An Assay of Genetic Variability through Phenological
Studies on Neem (Azadirachta indica A. Juss.)
Plantation
Materials and Methods
Observations and Discussions

7. Chemistry of Neem (Azadirachta indica), a Sustainable
Source of Natural Pesticides

8. Photo-oxidation of Tetranortriterpenoids
Materials and Methods
Results and Discussion

9. New Tetra and Pentanortriterpenoids from
Azadirachta indica A. Juss.
Results and Discussion
1 a-Destigloyl-1a-benzoylazadirachtin (II)
11b-Hydroxyazadirachtinin (III)
4a-benzoyl nimbandiol [V]
Ochinin Acetate [VII] and Ochinolide B [VIII]

10. Machineries for Neem Processing
Materials and Methods
Results and Discussion
Summary and conclusion
Suggestions for Furtehr Work

11. Engineering Properties of Neem Nut
Introduction
Review of Literature
Materials and Methods
Apparatus and Procedur
Dimensions and Hardness
Nut weight and Kernel-shell Mass Ratio
Angle of Repose
Porosity
Bulk Density and Particle Density
Friction
Preparation of Samples
Results and Discussion
Dimensions and Hardness
Nut Weight and Kernel-Shell Mass Ratio
Angle of Repose and Porosity
Bulk Density and Particle Density
Coefficient of Friction
Conclusions

12. Neem and Transfer of Technology
Use of Neem Pest Control
Transfer of Neem Technology to the Farmers in India
As Pest Control Agent
On Tobacco
On-Farm Trial
Demonstration Trials
Lab-to Land Programme
NSKS in Integrated Pest Management
On Cotton
On Paddy
On Pulses
On Castor
Use of Neem Cake as Nematicide
Use of Neem Oil as a Suckericide on Tobacco
Neem Cake as Organic Manure

13. Processing of Neem Fruit and Seed
Availability of neem
Collection and processing of fruit and seed
Depulpers, driers and decorticators
Driers
Decorticators
Discussion of Results
Maturity, storage and pressing of seed
Maturation of Oil in Stored Fruits
Depulping of The Neem Fruit
Cost of Operation
Crushing of Neem Seed Kernels in Wardha Ghani
Fall of Oil yield with Storage
Processing of Neem Seed Kernel and production of
Neem Oil
Crushing
Storage Experiments on Neem Seed
Conclusions
Characteristics of neem oil and its quality
Specific Gravity and Refractive Index
Acid Value
Alcohol Soluble Material in the oil
Other Characteristics
Unsaponifilable Matter

14. Processing of Neem Oil and its Utilization
Quantitative estimation of the differents constituents
of neem oil by alcohol extraction
Total Dilute Alcohol Extractive of Neem Oil
Large Scale Alcohol Extraction of Neem Oil
Refining of alcohol-extracted oil
Alkali Treatment
Refining Loss on Alkali Treatment
Bleaching of Neutral oil (Alcohol-Extracted and
Alkali-Refined)
Hydrogenation Experiments (Laboratory Scale) with
Neutral and Bleached Neem Oil
Refining Loss in Factory Pilot Unit
Tentative Cost of the Process of Alcohol Extraction
of Neem oil based on the Pilot Plant work
High Pressure Splitting
Deodorization and hydrogenation of purified and
refined oil
Alkali Refining
Hydrogenation of Refined Neem Oil
Soap
Stearin and olein
Pyronimin, a denaturant
Pyronimis-A Denaturant for Alcohol
Production of the Denaturants
Requirement of the Denaturants
Results of tests with the denatured spirit
Tentative Specifications for Pyronimin-250
Tentative Specifications for 'Total Bitters' Fraction
Tentative Specifications for the Spirit Denatured with
Pyronimin and 'Total Bitters' on Neem
Pharmaceutical Preparations with the Bitter Constituents
Preparations from Nimbidin-T and their uses
Costing
Other Experiments at Refining
Factors influencing industrial utilization of neem oil
and its by-products

15. Medicinal Uses
Uses of neem is indigenous system of medicine
Medicinal Uses of Neem in Recent Times

16. Cold Processing of Neem Seed
Experiment
Seed Cleaning
Mechanical Destoner
Mechanical Sieve-shaker Separator Fitted with
  Air Cyclone System
Sedimentation (Gravitational) Technique
Decoration of Seed
Crushing
Discussion

17. Products from Neem
Semi-greaseless cold cream
Skin toning lotions
Cream Cholesterin Type
Herbal Soap ( Neem based)
Neem based tooth paste
Radhas Ayurvedic Soap
Arya Neem Plus Turmeric Herbal Soap
Krishna Tulsi Herbal Soap
Medimix Skin Care Capsule
Shodha
Alargin forte
Beauty plus
Dantshodhak
Hemoclin syrup
Epidermoil Oil
Neem capsule
Charmi capsules
Hemocleen

18. Repellent Action of Neem Oil on Insects of
Public Health Importance
Methodology
Results
Discussion
Conclusion

19. Effect of Neem Oil: Structural and Functional
Change in the Epididymis of Rats
Materials and Methods
Neem Oil
Animals
Sperm Motility and Sperm Count
Biochemical Estimations
Histological Investigation
Statistical Analysis
Results
Discussion

20. Rat Toxicity Studies with Neem Oil
Materials and Methods
Neem Oil
Animals
Biochemical Studies
Statistical Analysis
Results
Tissue Biochemical Parameters
Blood and Serum Parameters
Histological Studies
Discussion

21. Evaluation of Neem Extract Sprays on Maize
Introduction
Materials and Methods
Results
Discussion

22. Antifeedant and Insecticidal Activity of Some
Neem Fractions
Materials and Methods
Results and Discussion

23. Azadirachta indica A. Juss. Stem Bark as an
  Anti-Leprosy Source
Materials and Methods
Observation and Results
Pharmacognosy
Macromorphology of Bark
Micromorphology of Bark
Powder Study
Phytochemistry
Biochemical Estimation (Percentage on Dry Weight Basis)
Geochemical Estimation
Active Principle Determination (from Ethanolic Extract)
Chemical Identity Comparison
Discussion

24. Evaluation of Neem Derivatives and Lantana camara L.
against Cardamom Pests
Materials and Methods
Field Evaluation of Neem Derivatives against the
Cardamom Thrips, Sciothrips cardamomi (Ramk.)
Field Evaluation of Neem Oil against Cardamom
Whitefly, Dialeurodes cardamomi David & Subr.
Laboratory Evaluation of the Crude Extract of Stem of
Lantana camara against the Cardamom Hairy
Caterpillar, Eupterots undata
Laboratory Evaluation of the Crude Extract of the Stem of
Lantana camara L. against Cardamom Shoot Borer,
Conogethes punctiferalis (Guen.)
Results and Discussion
Effect of Neem Derivatives on Cardamom Thrips
Effect of Neem Oil on Cardamom Whitefly
Effect of 1 per cent Suspension of the Extract of Lantana
camara on E. undata
Effect of 1 per cent Suspension of the Extract of L. camara
on C. punctiferalis

25. Development of a Neem Formulation and Its Evaluation
  for Control of Crop Pests
Materials and Methods
Product Development
Laboratory Studies
Field Studies
Results and Discussion
Laboratory Studies
Field Studies

26. Effect of Neem Cake, Neem Oil, Repelin and
Carbofuran on Control of Soybean Nematodes
Materials and Methods
Results and Discussion

27. Thyroid Hormones and Intermediary Metabolism
in Fish: Influence of Neem Kernel Extract
Materials and Methods
Results
Effect of T3 or T4 in Fish Injected with NKE
Effect of T3 and T4 in Fish Immersed in NKE-treated Water
Discussion

28. Clinical Studies with Praneem Polyherbal Cream in
Chlamydial Cervicitis
Materials and Methods
Polyherbal Cream
Patients
Diagnostic Methods for C. trachomatis
Dose Schedule
Follow-up
Results
Discussion

29. Identification and Characterization of the Immunomodulator
Fraction from Neem Seed Extract Responsible for
Long-term Anti-fertility Activity
Materials and Methods
Results
Conclusion

30. Identification of Effective and Inexpensive Neem
(Azadirachta indica A. Juss.) Seed Kernel Extract
Materials and Methods
Seed Collection and Processing
Extraction
Aqueous Extract (AE)
Ethanolic Extract (EtoHE)
Hexane Extract (HE)
Chloroform Extract of DNKP (CHEDK)
Ethanol Soluble (Eto HSHE) and Insoluble (EtoHIHE)
Part of Hexane Extract
Extract Yield
Formulation of the Extracts
Rearing Culture of H. armigera
Biological Testing
Oviposition
Ovicidal
Feeding deterrent
Growth and Development
Results
Effect on Oviposition
Effect on Egg Hatching
Effect on Feeding
Effect on Growth and Development
Pupal Mortality and Adult Emergence
Discussion
Effect of oviposition
Effect on Egg Hatching
Effect on Feeding
Effect on Growth and Development of Larvae
Conclusion

31. Field Evaluation of Some Botanical Insecticides Alone
and in Combination with Other Insecticides for
Management of Bollworm Complex on Cotton
Materials and Methods
Results and Discussion
RD-9 Repelin
Neemark
Ind-Ne
Conclusions

32. Evaluation of Enriched Neem (Azadirachta indica A. Juss.)
Seed Extracts against Mango Hoppers, Idioscopus
nitidulus Walker and Amritodus atkinsoni Leth.
Materials and Methods
Laboratory Trial
Field trials
Results
Laboratory trials
Field Trials
Evaluation of neem derivatives for control of mango
hopper, I. nitidulus
Discussion

33. Potential of Neem in Insect Pest Management in Rice
Introduction
Materials and Methods
Results and Discussion
Effect of Neem Oil on Rice Leaf Folder and Stem Borer
Efficacy of Neem-based Insecticides Against Stem Borer
Effect of Neem-based Insecticides on the Growth
and Development of White-backed Planthopper
Combination of Neem-based Products with Synthetic
Insecticides

34. Effect of Neem Kernel Extract and Neem Oil on Nutritive
and Reproductive Physiology of Heliothis armigera
Hub.
Materials and Methods
Mass Culture and Biological Studies
Preparation of Extracts
Treatment
Quantitative Food Utilization
Efficiency of Digestion
Reproduction Studies
Biochemical Assays
Enzyme Assays
RESULTS
Effects on Reproductive Parameters
Effects on Quantitative Food Utilization
Effects on Efficiency of Digestion and Digestive Enzymes
Effect on Protein, Glycogen, Lipid and Enzyme Profiles
in Subsequent Female Moths
Effect on Protein, Glycogen, Lipid and Enzyme Profiles
in Subsequent Male Moths
Discussion
Conclusion

35. Bioefficacy of Some Neem Formulations against
Spodoptera litura F.
Materials and Methods
Laboratory Tests
Nursery Experiment
Studies on Effect of Repelin B versus Repelin A and
NSKS against S. litura on Castor in Laboratory
Studies on Effect of Repelin B Alone and in Combination
with Endosulfan against S. litura (1992)
Bio-efficacy of Repelin B and Other New Neem
Formulations against S. litura on Tobacco (1992)
Results and Discussion
Laboratory Tests
Nursery Experiments
Effect of Repelin B versus Repelin A and NSKS against
S. litura on Castor in Laboratory
Choice Situations
No-choice Situation
Effect of Repelin B alone and in Combination with
Endosulfan against Tobacco Caterpillar, s. litura
on Tobacco
Bio-efficacy of Repelin B and Other New Neem
Formulations against S. litura (1992)
Laboratory tests
No-choice Situation
Nursery Tests

36. Effects of Extracts from Neem on Aphids
(Homoptera: Aphididae) and Their Natural Enemies
Materials and Methods
Azadirachtin Content
Aphid Control
Aphid Natural Enemies
Antifeedant Activity
Aphid Reproduction
Results and Discussion
Aphid Control
Aphid Natural Enemies
Antifeedant Activity
Aphid Growth and Development
Aphid Reproduction
Conclusion

37. Azadirachtin Content and Bioactivity of Some Neem
Ecotypes of India
Materials
Methods
Estimation of Azadirachtin Content
Kernels
Oil
Extraction and Enrichment
Physicochemical Properties of Oil
Azadirachtin Estimation by PHLC
Insect Growth Regulation (IGR)
Fungicidal Activity
Results and Discussion
Azadirachtin Content of Neem Ecotypes
Kernels
Oil
Enrichment
Insect Growth Regulation
Fungicidal Property

38. The Effects of Various Neem Formulations on Mortality
Rate and Morphogenetic Defects Upon Schistocerca
gregaria (Forskal) Larvae
Materials and Methods
Laboratory Insects
Field Insects
Neem Products
Controls
Application of the Larvae
Application of the Vegetation
Results
Mortality Rates Following Application of Neem
Products to Larvae
Mortality Rates after Treatment of the Plants with
Enriched Neem Oil; The Repellent Effect of Neem
Morphogenetic Defects
Discussion

39. Efficacy of Cakes in the Management of Root Knot
Nematode (M. arenaria) in Groundnut
Materials and Methods
Results and Discussion

40. Efficacy Profile of a Commercial Neem Insecticide
Factors Influencing the Commercial Success of
Azadirachtin
Consistency and Quality of Extracts
Product Positioning
Supply and Availability
Increase in Environmental Awareness
The Acceptance of Insect-Growth-Regulators
Cost of Raw Material
Important Commercial Characteristics of Azadirachtin
Representative Efficacy Data with Azatin/Turplex/Align
in the United States

41. Evaluation of Nematicidal Potential in Neem
Allelochemicals
Meterials and Methods
Results
Discussion

Directory Section

^ Top

Processing of Neem Fruit and Seed

Although India is proverbially rich in oilseed resources, the per capita consumption of fat in diet in this country is far below the required nutritional level. The reason may be ascribed to the non-availability of pure fats at reasonable price for consumption as food. Paradoxically enough, a large proportion of edible fats, particularly of groundnut and coconut, is used for soap making and other non-edible purposes. This is all the more astounding in view of the fact that non-edible oil resources rich in component acids primarily useful for good soap and allied industrial products are in plenty throughout the country. A number of so-called non-edible oils and fats if properly processed and refined are deemed superior to groundnut oil in a soapstock and some of them rich in lauric and myristic acids can advantageously replace coconut fat in soap industry and would substantially add to the lathering and detergent properties of the finished products. The resources of non-edible oilseeds have not hitherto been tapped properly on an economic and scientic background because of certain inherent difficulties peculiar to these raw materials, mainly, (i) disorganised and sometimes wild and scattered growth of these plants and consequent difficulties in the collection of the seeds, and (ii) the fats obtained are malodorous, of bitter acrid taste and dark colour and unless properly purified and refined, they would impart bad odour, colour and rancidity in the soap. Nevertheless, during the last decade due consideration is being given to the problem of utilisation of non-edible fats for soap industry. During the First Five-Year Plan period, the Cottage Industry Panel of the Planning Commission formulated a scheme for production of neem oil and its use in cottage soap industry. Eventually the Khadi and Village Industries Commission organised a Non-edible Oil and Soap Industry section and execution of the programme has since been undertaken in right earnest.

The Indian Central Oilseeds Committee, while considering ‘the increased production of oilseeds in India during the Second Five-Year Plan’, recognised the importance of developing the non-edible minor forest oilseeds and their utilization in industry. It, therefore, recommended that due attention should be paid to the possibility of increasing the utilization of minor oilseeds of forest origin. Estimates should also be made as to the extent they are being utilized at present, together with their potential sustained yield. The possibility of economic collection of these seeds should also be kept in view in the estimates to be made. In the opinion of the Committee the first thing to be done is to organise an economic collection of the seeds through village co-operatives at the appropriate centres. As the seeds now passed through various middlemen, inflating the cost, it was necessary to eliminate them with a view to making the collection economic. The price of oils extracted from such non-edible oilseeds should be appreciable lower than those of edible oils.

The problem is a complicated one involving several aspects which have to be properly co-ordinated before tangible results could be achieved. The various aspects involved are:

1. Analytical and characterisation work in the laboratory to determine the physical and chemical properties of the oil, the composition of the seeds and the oils, etc.

2. Processing and utilization of the seeds and the oils on a laboratory scale.

3. Similar experiments on a pilot plant scale.

4. Similar trials on a commercial scale.

5. Collection of the seeds and their immediate processing as to prevent their deterioration and thereby of the oil.

6. Conservation and propagation of the oilseeds-bearing plants and trees.

7. Dissemination of available information.

It has been indicated that a very intimate and active collaboration and co-operation among the various angencies are essential to achieve a rapid development and utilization of the non-edible oil resources in the country. These agencies are the agricultural and forest department of the various States, technological and research laboratories, small and large-scale industries utilising the oils, soap factories, etc. Although sporadic attempts are being made with regard to the collection of certain oilseeds such as neem, mahua, etc. and utilization of their oils, no sustained efforts have been maintained owing to the lack of an organisation comprehensive and powerful enough to bring all the various agencies together an co-ordinate their activities. The Indian Central Oilseeds Committee is in a position to assume this task.

It is the considered opinion of the Committee that a good deal of research work has been done on a number of non-edible oils, but further work on a large scale should be undertaken. Systematic pilot plant trials should be conducted at one or more research institutes on every aspect of processing the seeds and the oils extracted thereform. Such work should include depulping, decorticating, milling, pressing, solvent extraction, fat splitting, distillation of fatty acids, refining and finally prepration of products such as soaps, fatty acids, lubricants, varnishes and surface active agents.

Availability of neem

Amongst the non-edible oilseeds the potential availability of neem is by far the largest because of its very extensive growth throughout the country and fairly good yield of oils from the seeds. The results of a recent economic survey of non-edible oilseeds published by the Indian Central Oilseeds Committee show a consolidated all-India estimate of 417, 764 tons (1,12,79,650 mds.) of neem seeds. This estimate, however, does not appear to include the produce from some of the areas having extensive growth of neem trees, such as Delhi, parts of Central India, Orissa, etc. It is interesting to note that mahua (Madhuca indica) is second in availability but its potential availability is only about 50 per cent of that of neem.

It is reported that at the time when these surveys had been conducted, their economic importance had not been so much known and understood as at present. Hence, the need for a thorough survey to correctly assess the total potentialities as well as those that can be tapped should no longer be delayed.

Again, it has been found that population of neem trees is fairly concentrated in the northern and central India and to some extent in the South. In a very recent survey, the population of neem trees in Uttar Pradesh alone was estimated at 7.5 millions. It has thus been worked out that U.P. can produce 65,000 tons of neem oil. On an all-India basis, the potential production of neem oil would be of the order of 85,000 to 90,000 tons equivalent to about 10 crores of rupees, and which, when properly utilized, could satisfactorily replace groundnut and other edible oils now being used for soap manufacture.

The following Table 15 shows the population of neem trees in the different States as assessed under a scheme of economic survey of the oilseed bearing trees and plants, sponsored by the Indian Central Oilseeds Committee.

This estimate of 14 million trees does not, however, include the figures for Assam, Andhra, Bihar, Delhi, Orissa, Rajasthan, Punjab and Kerala.

Table 1.

State	Period of survey	Number of neem trees
Bombay	1953-54	11,70,000
Bhopal	1952-54	32,000
Hyderabad	1954-56	2,30,500
Madhya Bharat	1953-56	4,431,000
Mysore	1954	1,74,000
Saurashtra	1956-57	2,03,300
Vindhya Pradesh	1953-54	2,51,200
West Bengal	1956-57	2,65,000
Madras	1949-50	34,00,000
Uttar Pradesh	1957-58	75,00,000
Total	1,36,	57,000

A total all-India figure of 25 million neem trees in the country may not be a very liberal guess.

Collection and processing of fruit and seed

The neem seeds are collected during April-July in the rains and are sundried and stored till October-December or even later, when they are decorticated and kernel pressed in the ghani* (Plate 10). The main difficulties at present in harnessing such plentiful resources of oil are: (i) the harvest of the neem fruits is obtained within a very short time in the beginning of the rainy season or even after the monsoon sets in; (ii) the seed obtained contains a lot of moisture and deteriorates quickly during storage; and (iii) the oil possesses an offensive odour and bitter taste. The seed, while in storage, often gets so much charred on account of the heat produced by auto-oxidation than no oil can be produced out of it. To obviate these difficulties encountered in the successful utilization of this important raw material, both extensive and intensive investigations have been carried out with the different aspects of the problem, (i) to find out proper method of teatment of the fruit to produce good dry seed which can be stored throughout the year; (ii) to work out best method of pressing the seeds for oil; and (iii) to process the oil to remove the undesirable properties inherent in this oil.

Generally, the field officers of the Commission’s Non-edible Oil and Soap Industry section look after the collection of the seeds, etc. and put in efforts to solve the associated problems as enumerated above. A good deal of research work has been carried out at the J.B. Central Research Institute for Village Industries, Wardha, on the problem of processing of seeds, depulping, decortication, pressing of oil in ghanis, etc. Similar work on the processing of the seeds after the age-old conventional methods is being carried out at the various places where collection of neem seeds is sporadically organised by individuals or groups, sometimes with guidance from the State Departments of Agriculture or of Cottage and Village Industries. No mean achievement is reported from these disorganised centres in regard to the improvements in the methods of processing the seeds and their pressing vis-a-vis development of hand-operated contrivances and appliances.

The following description and discussion of the problem of neem seed collection and its processing are primarily based on the experiences recorded by the Khadi Commission field officers working on the project, during the last couple of years. Prior to that no systematic approach appears to have been made in tackling the problem of organized collection and processing with the ultimate objective of producing good quality oil in economically workable yields.

Deterioration of neem seeds when stocked without proper drying is a well-known fact to the workers dealing with the collection and processing of this seeds. It is, therefore, absolutely necessary to keep vigilance over the whole process, right from the initial stage of collection of the fruits in the villages.

According to Hervatte, there are places where it is possible to impress upon the local seed collectors the importance and the economic advantage in depulping the seed and then bringing depulped and dried seed to the collection centre. But at a majority of places, it is quite impossible to convince them and the centre has necessarily to purchase fresh neem fruit from the villagers, thus undertaking the entire work of processing the seed before storage. The neem fruits received at various collection centres, can be, according to him, roughly divided into following four categories.

A. Dried fruit.

B. Semi-dried fruit.

C. Fresh fruit (undried).

D. Wet and/or damaged fruit.

Each lot of fruits arriving at a rural collection centre is kept separately and mixed with another similar lot classified on the basis of above categories. Four broad types of fruit lots are thus obtained for the purpose of tackling the problem of initial dumping, temporary storage of preprocessed fruits, depulping, drying and final storage of seeds.

Initial dumping is usually made in heaps. These heaps should be mechanically agitated and raked at intervals so as to avoid stagnation and to help in dissipation of heat produced by fermentation of the carbohydrates present in the pulp and flesh above the seed coat, as well as respiration of the seed. The heaps should be comparatively smaller in height and frequency of the agitation should be more when the fruits contain larger amount of moisture. The thickness of the layer of the heap decides the degree of accumulation of heat and retention of moisture; both the factors go hand in hand to set in deterioration of the fruit. The C and D types of lots should never be stocked in big pyramidal heaps for more than one day. The A type fruits can be dumped in big heaps as also in tall bins temporarily made out of bamboo matting about 4’ in diameter. Such bins provide good ventilation and can, in fact, be used for storage of any dried fruit or seed in the absence of storage bags.

The agitation of the initial dumps is normally done by big fork-shaped agitators (used in agricultural operations) but a better and time-saving method would be to have three heaps in 3 quadrants of a storage area leaving the fourth quadrant vacant, as shown in the following figure:

Every day or as and when necessary, one of the heaps is shifted to the vacant space, the circulation always being done either clockwise or anticlockwise from one quadrant to the other. The shifting shuffles the heap completely upside down and incidentally provides the necessary aeration to it. Much less time is required in this operation which can be more effectively carried out if the heaps are on mattings instead of on the floor. Transfer from one mat to the other can be done simply by tilting the mat. As already mentioned, agitations or shiftings are more frequently required in the case of wet fruits than that of the semi-dried ones.

The fresh wet fruits would take the longest time for drying and it would be unwise to dry the fruit in wet and/or in damaged condition where the deterioration had already started and would proceed with accelerated rate even during drying. The prudent course would be, therefore, to depulp the fruit and then dry it.

In the case of semi-dried undamaged fruits, steps should be taken to dry them completely as quickly as possible either in bright sunshine or in a suitably devised drier. The completely dried whole fruits can be decorticated later and Kernels obtained for pressing.

As has already been stated, depulping, drying and decortication of the fruit or seed is of basic importance for large-scale production on neem oil of good quality. Recently, due attention was being given to these aspects of processing of neem seeds, and work has been carried out on the technological development of mechanical devices.

The work was undertaken primarily with a view to (a) designing and fabricating the necessary contraptions for processing the neem seed and practical trials thereon as well as (b) to arrive at a tentative layout of an economically workable neem seed processing unit.

Processing of neem fruit has hitherto been carried out in a rather crude and unscientific manner. In certain places where there is plenty of rain and infrequent sunshine during the neem fruit season, the fruit is collected and subjected to the following processing:

(i) depulping and washing of the fruits:

(ii) drying of the wet depulped seeds; and

(iii) decortication of the dried seed.

Depulpers, driers and decorticators

The depulping process involves the operations of soaking, depulping and washing.

For carrying out the soaking operation, cement concrete tanks of different sizes and capacities (14’ X 8’ X6’, 3‘ X 3’ X 3’, 5’ X 4’ X 6’) were constructed. The fruits were soaked with water in the tanks till the outer pulp got decomposed and became easily detachable. It took about 4 to 5 days depending upon the condition of the fruits and their moisture content.

The fruits were then transferred to the depulper. Two sizes of depulpers have been fabricated: a small hand-operated machine for treating about 40 kg. of fruits at a time. Both the machines are similar in design and essentially consist of a cylindrical steel drum with a central revolving shaft carrying blades, baffles being fitted on the wall of the drum.

The cost of the small-size machine worker out to about Rs. 4000//-.

In the washing machine which consists of a shaking sieve fitted in an inclined plane with a number of jets spraying water over it, the material from the depulper is charged at the higher end of the sieve and slides down as the sieve shakes and sprays of water play upon it. They pulpy matter is washed away with the water falling through the sieve while the depulped seed collect below the lower end of the sieve. The cost of the machine is estimated at about Rs. 700/-.

For the purpose of bringing down the moisture content of washed seeds below the critical level in the shortest possible time, merely sun drying is often inadequate and suitable types of driers are essential.

Driers

Three types of driers were designed and fabricated.

Tray driers. Two types of tray driers were designed. One type consists of a rectangular brickwork chamber (about 4’3" × 3’6" × 6’6") with a furnace by its side. The flue gases from the furnace pass through the chamber from top towards the bottom and finally pass through the chimney. Eight trays, each 3’6" X 3’6" X 2½”, with perforated bottoms are placed inside the chamber, one above the other with 8” spacing, being supported on angle irons fitted inside the chamber. Each tray leaves about 9” of space on one side of the wall, each alternate tray leaving such space in alternate side so that the hot flue gases have to pass through the chamber in a zig-zag manner until it leaves the chamber at the bottom. Each tray has a capacity of about 20-30 kg. of the fruit or seed. The fruit or seed to be dried is placed in trays which are then placed inside the chamber. After charging all the trays, the door of the chamber is closed and the hot flue gases from the furnace are allowed to pass through the chamber. Several trials on the drier showed that full charge weighing about 150-250 kg. of fruit of seed takes about 12 hours to dry consuming about 150-200 kg. Steam coal depending upon the moisture content. The estimated cost of the drier including the furnace worked out to be about Rs. 900/-.

The second type of tray drier designed is similar to the above, but it provides for hot air instead of hot flue gas being used for drying. Hot air is obtained by blowing air through a closed coil placed inside the flue of the furnace and is passed through the chamber containing the fruit or seed in trays. The hot air enters the chamber at the bottom and leaves it at the top. A few trials conducted on this drier showed that the drying period is much longer, viz. about 18-20 hours more than in the previous drier. In view of the higher initial cost and also higher processing cost due to power required for running the blower for longer period of drying, this type of drying was not considered feasible.

The estimated cost of the drier including the furnace and blower, etc. is about Rs. 1,500/-.

A thrid type of drier, a small hand-driven rotary drier, was also fabricated. It consists of a revolving drum surrounded by a jacket of hot flue gases coming from a furnace situated on one side of the drier. The drier is hand-operated and takes a charge of about 40 kg. at a time. A few trials conducted on this drier showed that one change takes time of about 16 hours to dry, consuming about 150 kg. Of steam coal. the cost of the drier worked out to about Rs. 425/-. It was not found economical.

Decorticators

Only the kernel of the neem seed is the seat of the fixed fat. It is, therefore, unnecessary to crush the whole fruit or seed to press out the oil. Apart from the extra load being put on the crushing machine (or ghani), the pressing of the whole fruit or seed is liable to yield a poorer quality of oil due to extrinsic impurities being carried from the seed and/or the fruit coat and also the yield of oil is less due to some of it being absorbed by the shell and/or pulp. Decortication, therefore, is a necessary operation in the processing of neem fruit.

The following two types of decorticators had been designed and fabricated at the Technological Institute:

Hand chakki. It is just an ordinary chakki, consisting of two circular discs one over the other. For this work, the lower disc was made of stone and the upper one was made of wood. The surfaces of the two discs facing each other were corrugated. To find out the optimum weight per square inch of the upper disc most suitable for decortication, the weight of the upper wooden disc was varied by fixing on its top iron plates of known weight. The chakki was tried for decortication of neem fruit as well as neem seed. In the case of neem fruit, it was not found satisfactory as the fruit, when passed through it, gets flattened but does not get broken. It was found to be quite satisfactory for neem seed. Its output is rather low, but it can be utilised with advantage for spare time working in villages.

A typical chakki of 15” diameter was worked on with a sample of seed (moisture, 6.5 per cent; kernel, 43.7 per cent) and it was found that with the increasing weight of the upper disc (0.11 to 0.16 lb. p. s. i.), decortication (percentage) increases from 83.0 to 100; but with this increment, however, the percentage of broken kernel increases from 3 to 24 and loss of kernel form 8.5 to 10.7 per cent. The optimum weight of disc is about 0.12 to 0.13 lb. p.s.i. The capacity of the chakki is about 15 to 20 lb. of seed per hour. A chakki from 23” to 30” diameter can be easily run by one man and its capacity may be about double that of the above chakki, i.e., about 30-40 lb. of seed per hour.

Decorticators consisting of one pair of rollers. These essentially consist of two cast iron rollers mounted side by side on a cast iron stand and moving in opposite directions by means of suitable gear arrangement and with arrangement either for mechanical drive or hand working. There is a feed hopper on top of the rollers with a slide plate for regulating the feed. The fruit or seed coming between the rollers gets broken due to the pressure of the rollers. The gap between the two rollers can be adjusted according to the size of the fruit or seed to be decorticated.

(a) Decorticator having plain rollers. As a result of trials carried out on a decorticator having plain rollers, it was not found satisfactory, evidently due to the lack of sufficient grip and want of cutting action in the rollers.

(b) Decorticators having grooved rollers. Following three types of decorticators have been designed and fabricated:

(1) Decorticator having rollers with longitudinal groovers.

(2) Decorticator having rollers with slanting groovers.

(3) Decorticator having rollers with circular grooves.

The grooves in cased had rounded bottoms. The dimensions of the grooves were as follows:

	Longitudinal	Slanting groovers at 10o	Circular
Depth (inches)....	1/16	1/16	1/16
Width (inches)...	1/8	1/8	1/8
Distance between two adjacent grooves (inches)...	1/8	1/4	1/16

A large number of trials were undertaken on each of the above types of decorticators. Experiments were carried out with varying gaps between the rollers. In the case of power-operation, experiments were performed only with neem fruit and with varying gaps and at different speeds of rollers. The neem fruit and seed used in the experiments were first separated into different sizes and experiments were then performed with a more or less uniform size of fruit or seed. The fruit was separated into two sizes, one which was retained on a sieve having three mesh per linear inch (+3) the other which passed through the above sieve but was retained and by a sieve having 4 mesh per linear inch (–3, +4). The seed was separated into three different sizes, one which was retained on a sieve having three mesh per linear inch (+3), another which passed through the above sieve but was retained on a sieve having four mesh per linear inch (–3, +4) and a third one which passed through the sieve having four mesh per linear inch (–4). Although in actual practice it may not be feasible to carry out such a size separation before decortication, yet it was considered necessary for the investigations in hand so as to get comparable results. In the case of experiments carried out with hand-operated decorticators, one kg. of fruit or seed was used for each experiment. In the case of power-driven decorticators, 10 kg. of fruit was used for each experiment. Each experiment was carried out with gap between the rollers varying from 1/16 to 3/16”; with each variation of seed size 5 experiments were carried out with progressive increase in the gap between the rollers. The results with the decorticators conditioned by the factors discussed above are summarised in Table 16.

The loss of kernel shown in the last column of the foregoing Table is theoretical percentage of kernel in the fruit seed taken–(percentage of kernel obtained + theoretical percentage of kernel left in the undecorticated fruit or seed). The separation of kernel from the husk and undecorticated seed after decortication has been effected by hand winnowing and the loss of kernel shown, therefore, represents small pieces of broken kernel which have escaped with the husk.

Cottonseed decorticator used for neem seeds. It essentially consists of a rotating barrel or cylinder carrying knives on its periphery and a concave or 'breast' which holds the stationary knives. The position of the cylinder in relation to the concave is adjustable. There is a feed hopper fitted with a feed roll and adjustable feed gate to ensure a regular feeds. The seed falling on the rotating barrel is caught between the rotating and the stationary knives and both the husk and the kernel are carried round to the lower and of the ‘breast’ end dropped out of the machine.

Experiments were also conducted to study the efficiency of the cottonseed decorticator (power-driven; speed, 340 r.p.m.) for decortication of neem fruit. Ten mds. of fruits were used in each experiment. While decortication achieved was from 80 to 100 per cent, broken kernel and loss in kernel were 25 to 65.6 and 5.3 to 7.7 per cent respectively, with the variation of the gap between revolving and stationary knives being 3/16” to 5/16”.

Discussion of Results

Decorticators with one pair of rollers having grooved surfaces. There can be three criteria for judging the performance of a decorticator, viz., (i) percentage decortication effected, (ii) decortication without undue breakage of kernel, and (iii) loss of kernel during decortication. As regards percentage decortication effected, it is considered that for proper decortication at least 75 per cent decortication should be achieved. As regards breaking on kernel and loss of kernels, these go hand in hand because greater the breakage of kernel, greater is the loss. Therefore, the higher the percentage of whole kernel, the better the decortication. Of course, greater the loss of kernel the more unsatisfactory is the decortication.

It may be observed from Table 16 that as regards hand-operated decorticators, results with neem fruit have been more satisfactory than with neem seed, there being greater losses in the case of the latter. From an over-all consideration, it appears that both circular and longitudinal grooves give more or less similar performance, whereas slanting grooves tend to produce more of broken kernel and hence leat to higher losses in the kernel.

Table 16

Decorticator	Seed Size	Decortications per cent		Broken kernel percent		Loss of kernel percent
		max.	min.	max.	min.	max.	min
(hand-operated) Roller grooves: Longitudinal.	3;-3	98.0	37.0	46.6	7.6	3.7	0.2
		94.8	18.0	61.9	3.2	7.8	T
	3;-3, 4;	98.5	39.0	66.8	3.5	14.7	T
	-4	96.6	6.5	65.9	3.5	11.5	T
		90.0	5.0	49.2	16.0	7.6	T
Salanting.	3;3	100.0	42.2	78.0	3.0	16.3	T
		100.0	20.6	74.0	2.0	15.8	T
	3;-3, 4;	100.0	36.0	74.2	1.9	22.7	T
	-4	100.0	6.4	73.5	0.3	23.5	T
		97.0	2.8	68.0	–	15.5	T
Circular. .. .	3;-3	96.3	32.8	6.7.7	–	2.5	T
		97.6	6.8	69.4	–	5.3	T
	3;-3, 4;	97.3	35.4	50.7	4.6	16.1	0.5
	-4	97.7	8.6	47.5	–	10.6