Unseen Power - Process Engineering

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PROCESSING, REFINEMENT AND VALUE ADDITION OF NON-WOOD FOREST PRODUCTS
T. De Silva and C.K. Atal^/INTRODUCTION
Non-wood forest products (NWFPs) have long been used for subsistence by communities living near forests. Indiscriminate felling of forests for timber has caused loss of biodiversity and many serious environmental problems, including damage to ecosystems, weather changes and soil erosion. The other valuable forest resources have been neglected.

Many people living in and near forests are unaware of the potential of that resource for income generation because they lack access to information on processing possibilities. Sustainable exploitation of these resources could improve their livelihood through supplemental income and employment. Tropical rain forests are particularly abundant with plants yielding essential oils, gums, medicines, tannins, and colorants.

More recently, NWFPs have received international attention as a result of:

the growth of green consumerism in developed countries;

more open international markets;

increasing awareness of biodiversity conservation and sustainable and protective use of forest resources;

realization, based on a growing number of reports, of the potential of multi-use forest management to generate rural income, and that in many cases NWFP yield more income over time than timber species from the same resource;

growing recognition of the need to involve people living near forests for sustainable management of forest resources.

The United Nations Conference on Environment and Development (UNCED) in 1992 brought these factors into bold focus and from that emerged an agenda for implementation. The Agenda 21, Chapter 11 ? Combatting deforestation, includes the promotion and development of NWFPs through value addition, domestic processing, and promotion of small-scale forest-based enterprises for rural income and employment. Many countries are now preparing plans for implementing Agenda 21, and NWFP programmes can be incorporated. Government commitment, the absence of which had previously posed a major constraint to NWFP development, appears serious.

Only a few developing countries have had the resources to carry out large-scale, commercial processing of NWFPs. Historically, most NWFPs have been exported to industrialized countries where they are processed as final products. However, with inexpensive equipment and small-scale operations, local processing of selected NWFPs can be environmentally and economically viable.

This paper will focus on the processing potential of commercially important NWFPs, particularly for the following products:

Essential oils and oleoresins;
Medicinal products;
Vegetable oils (small-scale production);
Tannins;
Dyes/colorants;
Sweetening agents;
Gums;
Balsams;
Waxes;
Fibre boards.

Most of these can be produced on a large-scale, but only a few lend themselves to local, small-scale processing due to requirements for capital investment, trained personnel and infrastructure.

IMPEDIMENTS TO DEVELOPMENT OF NWFP INDUSTRIES
Research on NWFPs has generally not considered commercial products, but focused instead on new drugs, which require large sums of money, long periods of research, and sophisticated facilities. A major constraint has been the lack of information on the social and economic benefits to be derived from appropriate industrial utilization of NWFPs.

Another major constraint in the industrial development of NWFPs has been the lack of financial support and incentives to the entrepreneurs as a result of the low priority that governments and banks have placed on these forest industries.

Besides these institutional obstacles, industries involved in processing NWFPs face uncertain supply due to natural disasters, and wide fluctuations in market demand.

Yet in many cases these obstacles have been successfully overcome and industries based on essential oils, tannins and medicinal plants have thrived. In some countries like China and India, these industries are competitive with those of industrialized countries.

Other problems associated with industries based on NWFPs in developing countries are:

Poor harvesting (indiscriminate) and post-harvest treatment practices;
Lack of research on development of high yielding varieties, domestication etc.;
Inefficient processing techniques leading to low yields and poor quality products;
Poor quality control procedures;
Lack of R&D on product and process development;
Difficulties in marketing;
Lack of local market for primary processed products;
Lack of downstream processing facilities;
Lack of trained personnel and equipment;
Lack of facilities to fabricate equipment locally;
Lack of access to latest technological and market information.

Small-scale processing by rural communities generally requires both access to centralized downstream factories and a regular market for the primary products. The link between secondary processing and consumer industries should also be strengthened in order to develop a healthy local chain of operations from farmer to consumer as a viable alternative to export.

REQUIREMENTS FOR NWFP INDUSTRIES

The main requirements for establishing a NWFP-processing industry are:

financial resources;
available raw materials;
a ready market for the finished products.

Steps in the process include:

Selection of NWFPs for processing based on facilities available and marketability;

Fabrication or procurement of equipment, provision of required services (water, energy, chemicals etc.);

Adaptation or development of agronomical practices, harvesting and post-harvest treatment;

Training in processing methods and quality control;

Actual processing, often with assistance either from experts, NGOs or international agencies;

Packaging and storage of finished products;

Marketing outlets (local or export). In some cases the primary processed product could be used as a raw material for downstream processing of fragrances, isolates, and flavours.

The viability of rural processing can also depend on local availability of water, energy, transport facilities, and skilled personnel.

Where running water is scarce, condensers used for producing essential oil could be air cooled.

Where electricity is not available, the only cheap source of energy may be fuelwood, in which case fuelwood should be promoted side by side with the steps toward rural production. In some instances the residue has been successfully used for compost-making where organic cultivation could be encouraged.

Because seasonal availability of raw materials often limits production, any programme for rural NWFP-based industries should carefully plan its product mix. The equipment should be versatile in use.

Initial processing activities can benefit from support by international organisations, and should proceed with market promotion and contacts. UNIDO's programme can support such development, provided other support also exists. Once established, local operations may then require only marginal assistance in terms of market information and new technologies.

PRODUCTS FOR EXPORT

For products intended for export, scale of production often poses the main problem. Export orders are usually large and required on a time schedule. The needed large-scale processing and storage facilities require large capital investments. In such cases central processing will be the choice. Energy requirements and pollution risk can be reduced by centralized processing.

The problem of scale can be overcome by organising rural producers into cooperatives, so that small-scale processing can be practicable, provided the availability of facilities such as fuel oils or generators. For essential oils, mobile distillation units provide another way for a processing venture to cover wide areas where raw materials are available.

Manual equipment can be preferable for rural production of medicines in simple dosage forms. Small generators can supply all the electricity needs, or use of biogas can be promoted.

Products for export have to satisfy stringent criteria of quality. To reduce the risk of marketability, it can be advisable to select a product that is presently imported, to ensure a local market as well.

Figure 1 shows a scheme for establishing processing industries based on NWFPs. Proper coordination of the multidisciplinary activities is vital for the success of industries venturing into this field.

STAGES OF PROCESSING

The following example of medicinal plants shows how progressively more sophisticated processing methods can be introduced in stages.

Stage I 1) Harvesting of authentic material
2) Good post-harvest treatment

Stage II 3) Stage I followed by comminution of raw materials
4) Packaging of powders as uniform doses
5) Formulation of pills from powder
6) Production of medicinal wines under controlled conditions which will
need a sugar source

Stage III 7) 1, 2 and 3 followed by aqueous extraction
8) Preparation of standardised extracts (liquid and solid)
9) Formulation into dosage forms, capsules, sachets.

Stage IV 10) Stage III followed by conversion into other dosage forms such as tablets,
syrups, ointments

Stage V 11) 1, 2 and 3 followed by preparation of extracts with other solvents
12) Fractionation of extracts
13) Activity screening of extracts
14) Formulation into dosage forms

Stage VI 15) Isolation of pure phytopharmaceuticals from 8, 11 or 12
16) Conversion into semi-synthetic drugs
17) Formulation of 15 and 16 into dosage forms including injections

Stage VII New drug development

The first stage can take place in remote villages, with products transported to nearby towns for further processing. This requires no energy sources, sophisticated packaging material, or background technical education. Rural producers will need training only in harvesting methods, post-harvest treatments, and simple packaging.

The other stages will depend on the pace of local development. In most rural areas, Stage II is desirable. When all the needed facilities are available, this can to be upgraded to Stage III.

Figure 1

Stage VI is possible in developing countries that can afford to invest large sums of money or establish joint ventures with companies from industrialized countries. Apart from a few like India and China, most developing countries, have neither facilities nor money for the initiation of Stage VII.

Increasing sophistication in processing can follow the same pattern for production of essential oils, again depending on the facilities available. Primary processing in that case will require an energy source and a supply of water. Mobile distillation units can be introduced if roads exist for easy access.

HARVESTING AND POST-HARVEST TREATMENT

Indiscriminate harvesting of NWFPs can be minimized by creating a regular but limited demand with processing units that support a supply from sustainable harvesting. Assessments of the impact of harvesting NWFPs on biodiversity should proceed before launching into ventures that require a regular supply of NWFP materials.

Domestication of species offers another tool for ensuring steady and environmentally sustainable supply.

Raw materials which are to be kept after harvesting have to be dried and stored properly to prevent any deterioration and infestation. Therefore, harvesting and post-harvest treatments have to be linked with the processing schedule and can vary from crop to crop.

For example, the yields of essential oils obtained from aromatic plants will depend on the harvesting stage and post-harvest treatment. Following factors which can differ from raw materials to raw materials can influence the yield.

Stage of harvesting (maturation, flowering stage);
Time of harvesting (early morning, evening etc.);
Rate of drying (avoid decomposition);
Temperature of drying (avoid decomposition);
Moisture content after drying (avoid molds growth);
Storage conditions (prevent hydrolysis, oxidation, infestation);
Storage time before processing (loss of oil).

The optimum conditions have thus to be determined for each plant material. For further consideration of this topic, see the satellite paper by Clay in this volume.

RAW MATERIAL SUPPLY

Any R&D programme on such products should plan the supply situation before launching consumer products with a high demand. Nursery approach on raw materials should be initiated in order to safeguard the natural flora.

The case of taxol extraction from the bark of the Pacific Yew illustrates this. In 1961, the National Cancer Institute (NCI) started a massive anticancer screening programme which identified taxol from the Pacific yew tree (Taxus brevifoia) as the most promising candidate for cancer treatment. By 1991, NCI had invested US$ 27 million in taxol research. Although the prospective dose of taxol was only 2 g/patient/year, obtaining just 25 kg taxol (enough for 12,500 patients) would require felling of 38,000 trees. It became apparent that the long-term demand for taxol would outstrip all available supply of bark. This led NCI to collaborate with another firm to develop genetic selection and clonal propagation techniques for extracting taxol. The resulting research led Weyerhauser, the commercial forestry firm, to cultivate 15 million yew plants, and to assure adequate clinical supply of taxol for years to come.

SELECTION OF MULTI-USE SPECIES

Afforestation programmes associated with local processing (e.g. through agroforestry) should consider species with multiple uses. This ensures a product mix, and can also provide farmers with various primary products for subsistence or sale.

Neem (Azadirachta indica) provides an example of such a species. Abundant in Asia, neem provides a range of products, including an insecticide that is highly competitive in price and quality with petroleum-based synthetic insecticides.

Soap production from neem oil is the most feasible industrial option. Neem seed cake left after extraction of the oil represents 80 percent by weight of the whole seed. Parts of neem tree are also used in the preparation of traditional medicines.

ORGANIC PRODUCTS

There is a growing demand in industrialized countries for natural products in place of synthetic compounds, not only as food and medicine but for other consumer products as well. Use of essential oils in aromatherapy is increasing, creating a demand for exotic oils. The oils produced from organically grown plants without the use of synthetics such as fertilizers, pesticides or other chemicals, trade at premium prices sometimes three to five times the price of conventional oils.

Production of so called "organic products" requires labour for weeding and the use of organic fertilizers. Hence developing countries which have cheap labour and unpolluted land can opt for organic cultivation. As the present demand is relatively low, small-scale production would be best. Rural based industries with simple steam distillation, using non-contaminating stills, would yield the organic oils. A buyer could monitor the whole cycle from planting to the finished product. There is a system whereby buyers grant certification for production of organic products after inspection.

With the trend for green products increasing, it is expected that some industrialized countries will insist on eco-labelling of products as a condition of import. This could mean that any NWFP has to have a certificate ensuring that no ecological damage has been caused by its production.

PROCESSING FACTORS IN VALUE ADDITION

Secondary processing activities for local "value addition" require considerable research and development. Local research capabilities may have to be strengthened for work on NWFPs, and incentives, often merely through greater awareness of potential impact for the country, to scientists to pursue such research.

In some cases, the obstacle is lack of conversion of applied research results to industry. In this case, facilities to develop process parameters and products at a pilot scale can help.

UNIDO has helped to bridge this gap by introducing a polyvalent pilot plant for processing medicinal and aromatic plants and spices. This plant has enabled researchers to produce final products for market-testing. This has strengthened university-industry links, and encouraged universities by demonstrating the potential of industrialization of their R&D work. Particularly for medicinal products that require years of clinical testing before marketing, institutions that want to initiate downstream processing of NWFPs should possess facilities for pilot scale production.

POLYVALENT PILOT PLANT

As mentioned above, the gap the laboratory to industry can be bridged by pilot-scale processing, which allows chemical engineers to translate bench-scale findings to industrial-scale outputs.

UNIDO's polyvalent pilot plant design (Figure 2) includes all engineering drawings, specifications, and bills of quantities, so that it can be fabricated in all countries with facilities for stainless-steel welding. The plant allows for simplicity of design, installation, operation, maintenance, and repair. Its features include:

Modular construction, to permit increases in capacity and function by adding modules. One can add more unit operations or more sophisticated capabilities later.

Independent operation of plant components.

Capacity for aqueous or solvent extraction, continuous extraction, preparation of solid extracts, oleoresins, distillation of essential oils and if needed, fractionation of essential oils and production of absolutes and concretes, and even processing of other economic plant-derived products.

Adaptability for developing indigenous technologies locally.

Opportunity for training local personnel in the processing of medicinal plants, aromatic plants and spices. Other areas of training include plant operation, process control, quality assurance, trouble-shooting, maintenance, repair and management.

Easy replacement of standardized and optimized process control and measuring units, pumps and other ancillaries.

Simple and accessible plumbing and electrical wiring.

This plant has been introduced successfully in many situations.

QUALITY CRITERIA

Processed products must comply with national and international specifications. There are International Standard Specifications for most processed NWFPs. In addition to these, importing countries and buyers may have their own requirements. Processing methods must account for these requirements. In most case, quality has to start with the use of good quality raw materials and post-harvest treatment that avoids contamination.

Quality requirements for medicinal plants are still more stringent in terms of toxic materials and active principles. Compound medicines demands much research in order to develop specifications by which a standardized uniform product is obtained.

Export products also involve legal requirements governing registration and packaging.

Stringent requirements are being introduced presently to safeguard the environment, to reduce pollution caused by use of synthetic chemicals and reduce health risks due to side effects of using synthetic materials. Increasingly, the machinery and processes used in industries require validation to comply with International Standards Organizations (ISO) norms, particularly ISO 9000 series. The products have to conform to ISO specifications and other pharmacopoeial or buyer specifications. Furthermore eco-audit procedures will be required for safeguarding environmental damage. Organic production will reduce the risks of contamination of products and the environment with synthetic chemicals.

Figure 2

Benefits are reported by leading companies who have got ISO 9000 certification. One chemical plant reports a US$ 2.4 million/year savings merely by reducing the production of non-conforming material, eliminating unnecessary tasks etc. A new specification ISO 14000 series is expected to add an environmental dimension to the quality standard. This will be equivalent to the European eco-audit and management scheme (EMAS) currently in effect in Europe. These requirements have to be taken into account when planning industrial production of NWFPs in developing countries as ISO regulations will have an impact on marketing of the products.

The awareness of quality criteria is increasing in the developing countries and new regulations governing safety of products, quality specifications and good manufacturing procedures are being enacted.

RANGE OF PROCESSED NWFPs AND THE RELATED TECHNIQUES

The following is a discussion of industrially processed NWFPs.

Essential Oils

Figure 3 shows products that could be derived from aromatic plants and the related production processes. The cost of production varies depending on the raw materials, facilities for processing, and labour and energy costs. Their production on a large industrial scale requires significant variations in the technologies used. In case of rural small-scale processing these technologies have to be adapted to suit the existing situation at field level.

The international market for essential oils is dominated by a few countries. Some of these countries import oils from developing countries and export them after refinement or blending.The market is quite competitive and protected. Hence the developing countries have to develop strong market strategies for promotion of their products.

Steam distillation is the widely used technique in the extraction of essential oils. In this process, steam is passed through the plant material whereby the constituents that are volatile in steams are carried along with the steam. Steam can be generated in a separate boiler or at the bottom of the still by direct heating. The advantage is that the volatile components can be distilled at temperatures lower than the boiling points of their individual constituents, and that on condensing, the oils, being immiscible in water, forms a layer thereby easing separation. Though the process sounds simple in theory, the actual commercial process for greatest efficiency and quality varies widely, depending on the characteristics of the raw material and the final product.

Production of some expensive essential oils from flowers such as jasmine and rose takes place through a process called enfleurage. This is a technique by which the raw material is kept in contact with fat in order to get the fat saturated with the essential oil. The adsorbed oil is then extracted from the fat using ethanol. The ethanol is finally distilled off to yield the oil. This will contain all compounds that are adsorbed into the fat.

Some parts of plants that contain very minute amounts of essential oils such as flowers are extracted using low boiling solvents such as hexane, pentane or petroleum ether. These extracts will contain all material soluble in the solvent including the essential oil compounds. The process of separation of the essential oil needs an additional step of removal of the solvent in a separate evaporator (Figure 4). This is an expensive step due to the cost of solvents and the cost of production will depend on the efficiency of the recovery of the solvent for re-use. Hence this process has to be done at a central facility using good manufacturing practices. The scale of production will determine the economy of the process.

Figure. 3

Figure 4:

Absolutes

Certain finished perfumery products like colognes use the alcohol soluble fraction of concretes called absolutes. The concretes are mixed with alcohol and stirred vigorously to get all alcohol soluble compounds into solution. On cooling the mixture, alcohol insoluble compounds separate out at the bottom. The alcohol extract is filtered and the alcohol is evaporated in an evaporator to yield the absolute. In this case too a primary evaporator and a secondary evaporator are used.

Oleoresins

The extraction of spices such as ginger, pepper, chili, cardamon using solvents and the removal of these solvents as in the case of concretes yields oleoresins, which contain not only the essential oil compounds but other flavour principles of the spice such as pungency, waxes and other solvent soluble extractives. Oleoresins therefore are more representative of the spice than the essential oil obtained from it. The extraction process could be a continuous soxhlet extraction process or solvent percolation through a series of extractors.

Downstream Processing of Essential Oils

Essential oils could be further processed or rectified to add value. The main industrial uses of essential oils are indicated in Figure 5. Rectification of essential oils is sometimes needed depending on their end uses. The process of rectification may consist of one or more of the following:

removal of moisture, colour and sediments;
removal of compounds in order to improve the odour characteristics, stability and sustainability;
isolation of compounds that are highly valued;
enrich the oils by removing or adding other fractions.

This is done by a process of fractionation which could be carried out in some developed rural areas having small-scale processing with back up from national research institutions who would carry out the analysis and develop the fractionation parameters. This needs more training and equipment and many not be possible in certain rural communities or with forest dwellers. It would be better to carry out the fractionation of oils at a central facility which can afford to invest the funds and personnel required for this activity. As a result of fractionation pure isolates of added value such as citronellal and citral could be produced.

Figure 5

These isolates could further be processed using chemical methods to produce high value aroma chemicals which have an export market. These aroma chemicals can be used in blending of perfumes and flavours for local industries.

Medicinal Plants Products

About 80 percent of the world population still depend on medicinal plants for their health care. Medicines prepared using traditional methods are still used by the practising healers in the developing countries. Hence there is a demand for these traditional medicines which are prepared using wildly growing plant species. Around 20 percent of the drugs in modern pharmacopoeias are also plant derived, either as pure phytopharmaceuticals extracted from plants or as synthetic derivatives of them. Although the raw materials for the production of phytopharmaceuticals have been produced by crop-wise cultivation of selected varieties of plants, most of those used for traditional medicines have been collected from the forests. In fact this had in certain instances lead to threats of extinction of some valuable species. Hence it is imperative that domestication and cultivation of medicinal plants have to be initiated. In order to encourage cultivation, guarantee of purchase of these plants has to be given. This could only be achieved by introducing small-scale processing units for the production of traditional medicines. These NWFPs in some cases could be sustainably harvested from forests for small-scale processing whilst systematic cultivation has to be introduced to meet the demands for medicines at the national level.

Figure 6 shows the industrial products that can be obtained from medicinal plants.

The medicines for internal use prepared in the traditional manner involve simple methods such as hot or cold water extraction, expression of juice after crushing, powdering of dried material, formulation of powder into pastes via such a vehicle as water, oil or honey, and even fermentation after adding a sugar source.

Downstream Processing of Medicinal Plants

Preparation of standard extracts and conversion of them into dosage forms are activities that can be done as a rural based small industry to meet the demands of the local population. This is necessary in areas where traditional medicines are the main form of treatment.

The value of medicinal plants as a source of foreign exchange for developing countries depends on the use of those plants as raw materials in the pharmaceutical industry. These raw materials are used to:

Isolate pure active compounds (phytopharmaceuticals) for formulation into drugs;

Isolate intermediates for the production of semi-synthetic drugs;

Prepare standardised galenicals (extracts, powders, tinctures).

If one is to produce known pure phytopharmaceuticals used in modern medicine such as quinine, reserpine more processing stages and more sophisticated machinery are required. Furthermore safety and pollution aspects have to be considered. As these compounds occur in small quantities in the plant source, large amounts of raw materials have to be processed in order to benefit by economy of scale of production. Hence large-scale central processing is the only solution but costs have to be minimized to be competitive in the market.

Most of these processes and formulations are patent protected. Even transferring technology through contractual agreements and payment will not be of much help unless there is a large local demand for these drugs. Often the drugs so produced are more expensive than world market prices owing to the limitations of the economy of scale of production. Hence any country venturing into such activity should be able to use most of the production within the country.

Figure 6

If the isolation of the pure compound is patent protected or involves complex and sophisticated procedures and equipment, some value of raw materials can be retained by producing concentrates of the plant in the countries of origin. But this will need prior agreements with the buyers as some pharmaceutical firms do not favour the purchase of extracts.

Certain plants are rich sources of intermediates used in the production of drugs. The primary processing of parts of plants containing the intermediates could be carried out in the country of origin thus retaining some value of the resource material. For example diosgenin (from Dioscoria sp.) and hecogenin (from sisal) used in the production of steroids can be commercially produced in the countries of origin where there are steady supplies of sufficient raw materials.

The processed product (galenicals) from the plant could be a standardised fluid/solid extract or a powder or a tincture. These have to be formulated for incorporation into modern dosage forms. New formulations require some development work, particularly on account of the nature of the processed products. Plant extracts are difficult to granulate; they are sensitive to moisture and prone to microbial contamination. Hence the types of excipients to be used and the processing parameters have to be determined. The downstream processing activities leading to different medicinal plant based products are indicated in Figure 7.

The potential of the know how available with traditional healers and the rural people with regard to the use of plants as curatives, has not yet been fully tapped. Many plants from traditional uses have been useful in the development of new modern drugs. Many have been models for subsequent new drug development. The R&D with respect to new drug development is very expensive and requires long periods of work. For developing countries, this activity seems to be a virtual impossibility due to financial constraints. Hence it is proposed that joint research programmes be organised with industrialized country scientists or firms with safeguards to guarantee sharing of profits in the event of a successful outcome of a new drug. Already such activities are taking place as in the case of Costa Rica. But it has to be emphasized that more safeguards and intellectual property issues have to be worked out for successful partnerships in this regard.

Several joint venture models are now in operations. The innovative agreement entered into between the National Biodiversity Institute (INBio) in Costa Rica and the pharmaceutical company, Merck, can be cited as a case study. INBio is a non-profit Costa Rican institution dedicated to the conservation of the rich biodiversity by facilitating non-destructive and economic uses by national and international enterprises.

INBio signed a two-year agreement with Merck to analyze and prospect a limited number of Costa Rican plants, insects and micro organisms for biologically active compounds. The agreement was aimed at enabling Costa Rica to obtain the funds and expenses needed to effectively protect her biodiversity. A payment of US$ 1 million was payable by Merck to INBio at the beginning of the project, 10 percent of which was earmarked for the Costa Rica's conservation programme.

Remaining funds were to be used to partially cover the cost of the biodiversity inventory that INBio is conducting as well as the costs of collecting, analyzing and preparing samples of extracts to be sent to Merck. INBio is to receive royalties in a fair share of profits from the commercialization of any product or information derived from the samples sent to Merck. In the pharmaceutical industry this can take up to 15 years and involves high intrinsic risks. Hence any pay offs from this agreement has to await the introduction of a new drug into the market. By integrating and building its human and material resources in collaboration with a highly capable and successful company, INBio hopes to find new products as well as sustainable uses for its forests and biodiversity.

Figure 7

Another area for R&D work which would result in success could be to work on biopesticides as there is a strong move to reduce the use of synthetic products. Already new plants have emerged as promising candidates apart from the already widely used pyrethrins. Neem tree extracts are now being studied and some new bioactive products have been isolated. This is a good NWFP for expansion as the world market for pesticides is very large. More plants have to be subjected to R&D, some leads could be obtained from traditional uses.

Vegetable Oils

Many forest trees possess fatty oil containing seeds which could be processed to give vegetable oils. Edible oils are used as cooking oils and in the food industry. Bulk of the oil is used in soap-making on both small and large scale. Some are used as components of other industrial products after secondary processing. Many of the oils are industrially produced on a commercial scale. But the process of production of fixed oils is simple and can be carried out at rural level. The equipment required is simple and can be fabricated in the country. bsp;

The primary processing of seeds to yield the oil is dry expression avoiding contamination and taking care not to subject to temperatures leading to decomposition. Sometimes boiling the crushed raw material in water will yield the solid fat on cooling. Training in harvesting the fruits at the optimum maturity and processing can be easily imparted. In fact the processing has been practised as a cottage industry in many countries for subsistence uses.

Secondary Processing of Vegetable Oils

Apart from cooking oil and domestic lighting, vegetable oils have also been used as a fuel in small diesel engines, enabling a certain degree of mechanization in rural areas.

Although the oils are primarily exported, they can be further processed to yield much more valuable products for a number of industries. For example, lauric oils yield C₁₂-C₁₅ fatty alcohol derivatives, which are components of detergents. These alcohol derivatives, originally made exclusively from lauric oils, now come from petroleum synthetics. The growing demand for natural products could boost the demand for fatty alcohol derivatives from lauric oils. This will be a growing market to be exploited by the palm oil producing countries by downstream processing of their oils to produce these fatty alcohol derivatives. This multi-billion dollar lauric oil market is supplied by palm kernels mainly from coconuts (Cocos nucifera L. - 2,573,000 t of oil/yr) and the African oil palm (Elaeis guineensis Jacq. - 997,000 t/yr). Small amounts are also obtained from wild groves of the babassu palm (Orbignya sp.) in Brazil (150,000 t/yr) and a few other Central and South American palms such as Acrocomia aculeata, Scheelea martina, Syagnu species and Astrocaryum species.

Tannins

Tannins are a group of non-crystallisable compounds widely distributed in plants, but usually localized in specific parts such as beans, nuts, fruits, barks, and stems. In addition to combining with animal skins to form a strong and flexible leather, tannins also react with salts of iron to form dark-blue or greenish-black compounds, the basis of common inks. Tanning materials are often utilized in oil drilling to reduce the viscosity of the drill without reducing the specific gravity and in the production of pharmaceuticals. The main industrial uses of tannins are leather, dyes, inks, antioxidants, lubricants, and drugs.

Tannins are extracted from many plant sources. The processing of the plant parts to obtain tannin extracts and tannin powder, though simple, needs carefully controlled conditions.

Dyes and Colorants

Colouring for food, textiles, paper and paints were originally obtained from plant and mineral resources. With the advent of synthetic dyes and pigments, the demand for natural dyes decreased so much so use of natural dyes was almost restricted to some food uses. Due to the toxic nature of synthetic dyes and pigments, particularly if used in quantities in excess of permissible limits, and the emerging demand for naturals, there is a resurgence of interest for natural dyes and pigments. Many of the forest resources are rich in dyes and pigments and hence could be sustainably harvested for commercial use. Industrial processing of the raw materials collected could be carried out at rural level if supplies of raw material are not very large.

Sweetening Agents

Many countries have sources of plant based sweeteners other than industrially produced sugar. These can be good substitutes in rural areas as people do not always have access to refined sugar. Some of the resources for getting the sweeteners are the sap of palm flowers, parts of plants such as leaves of stevia, arils of Thaumatococcus daniellii and bark sap of the maple tree. The final products are syrups, powders and solids. In addition bees honey obtained as a NWFP is used as a sweetening agent. The primary processing of these raw materials is simple and can be carried out at rural level. The training required can be imparted and the equipment needed fabricated locally. In many instances, fermentation has to be prevented and any toxic substances have to be removed as in the case of stevia where heavy metals is a problem. Processing as a small-scale industry can be cost effective and the product has a local market as well as a secondary use in confectioneries. The remaining liquor (molasses) could be fermented to yield alcoholic beverages and vinegar.

Gums

Gums are natural hydrocolloids mostly produced by plants as a protective after injury. They have diverse applications in pharmaceutical, cosmetic, food and textile industries. Though many synthetic products have replaced the uses of natural gums, their use continues for specific purposes. The move for green products is sure to give a boost to the production of natural gums.

As a food additive, a wide range of toxicological evaluation is needed to satisfy the international regulatory committees concerned with the safety of food and with specifications of their identity and purity. Gums of the identity and quality permitted for use in foodstuffs command high prices, but there is a large supply of gums from many other botanical sources which subsequently only command low prices for use in technological (i.e. non-food) applications. It is important for exporters and merchants in gum-producing countries, to monitor the decisions of the international regulatory committees as these greatly influence international gum trading.

Gums and resins are used in industries for paper, textiles, adhesive, pharmaceutical, food, and perfumery, as well as in paints, coatings, printing, detergents, and cosmetics. In addition gums from other plants are locally used and new uses for these gums are being investigated.

Balsams

Balsams are resinous mixtures containing large amounts of benzoic acid and cinnamic acids or esters of these acids. They are used in medicine other consumer industries. These are mainly pathogenic products obtained as exudates from trees.

Waxes

Natural waxes are NWFPs of commercial value used as components of industrial products like candles, varnishes, pharmaceuticals and cosmetics. Some of them are collected, melted and formed into cakes or pieces. Some waxes such as candellila can be obtained by solvent extraction. These too can be processed at rural level for income generation. Even with severe competition from synthetic waxes, some specific properties of natural waxes have kept them in demand. The processing and refining of the wax oils are simple but important in order to produce good quality grades.

Fibre Boards

Some parts of plants or residues after extraction of the main product could be used to produce other products such as fibre board boxes and hand made paper. Pine needles are one such source of lignocellulose which could be converted to fibre board for use as packing material.

It is estimated that on an average, the availability of needles of Pinus roxburghii per ha is between 2.5-3 t/ha. Even a portion of the needles (15-20 percent) if collected from easily approachable forests, will be sufficient to meet the requirement of number of small mills. It will help in preventing the forest fires without disturbing the ecology. The areas under Pinus roxburghii in the sub-Himalayan region is 1 million hectares. The needles could be collected (April-June) with rakes and baled at the site with mobile baling presses for transportation. The process for the production of fibre boards from pine needle used in the sub Himalayan region in India is simple and can be adapted by other countries.

The process does not require any binder. The process consists in giving a softening treatment in a rotary digester followed by defibration to get a suitable pulp, in a Hollander type beater. The pulp is blended with pulp made from waste paper, then converted into a sheet in a sheet-former of a single cylinder machine. The wet sheets (2 or 3) from cylinder machine are laminated and hot pressed to get a thicknesses of 3.2 mm. The boards are given a coating to make them water resistant. The yield of the fibre board is 55-60 percent based on the moisture free weight of the needles. The board is converted into packing boxes using wooden battens which are stapled with a machine specially designed for the purpose. A few perforations or slots are given to the board for fruit breathing. Fibre angles could also be used in place of wooden battens for converting the board into a box.

The main effluents of the plant are dissolved matter and small quantities of suspended lignocellulosic fines. These pass through the washing screen. The effluent from the mildly cooked pine needles contain the dissolved matter consisting of mainly colouring matter, resinous substances and some quantity of lignin. About 7-8 cubic meters of liquor will be obtained from each ton of digested needles. The pH of the liquor is around 6 and could be disposed in a close dry channel if available. If not available, some detention tanks may have to be provided, along with an arrangement to remove the suspended particles. The tanks could be emptied during rainy season when the liquor gets diluted with rain water.

This simple and appropriate technology may prove useful particularly in rural and hilly areas as well as in certain developing countries where pine needles and surplus agriculture residues are available.

MARKET STRATEGIES

Marketing problems often beset the industrial development of NWFPs in developing countries as it is a function of two groups, the rich buyers and the helpless producers. The prices are dictated by the buyers who control the market. Poor producers have been let down so many times that some have given up processing NWFPs in favour of other livelihoods. As a result, there could be the eventual disappearance of certain products from the markets. A case in point is the producers of Ylang Ylang oil in the Indian Ocean Region countries who are abandoning this product in favour of other crops because of the unreliability and the low prices of the market. Therefore the investment on and promotion of industrial processing of NWFPs has to carefully consider marketability and the use of these as products for import substitution. Alternatively, local utilization of NWFPs for downstream processing and development of new products could be encouraged.

Some regular suppliers of NWFPs to the world market are reducing their supply as a result of increased local utilization. These niches in markets should be identified and included in planning of products for industrial production. All attempts should be made to minimize production costs and improve the quality of the products in order to be in a better position to compete in the world markets. Trade promotional activities should be seriously undertaken by the Governments in order to advertise their specific products and to negotiate marketing agreements.

Although the green movement in industrialized countries is creating increased demand for natural NWFPs, "green" products still must comply standard specifications and legal requirements of the countries. Furthermore, price of production still has to be minimized in order to be competitive in the world market. The protective nature of the markets and price fluctuations both dictate the need for considered market strategies. It could be more advantageous to decide on the scale of production based on local and national demands and the possibilities for secondary processing or use in the manufacture of other consumer products such as soaps, cosmetics and pharmaceuticals.

RESEARCH AND DEVELOPMENT

Much research and development work is required to tap the full potential of NWFPs. Industries of essential oils, dyes, medicinal plant products established to date have been a result of R&D on naturally occurring plant species. Research has studied only a fraction of the flora. Research needs range from development of superior propagation materials, agrotechnology, to new products and marketing of finished products. Moreover once research leads are found, it also takes time and more development work before being accepted for use as drugs or as additives in other consumer products.

Because industrial research in developed countries focuses on synthetic substitutes as soon as a new useful natural product is discovered, it is vital for developing countries to safeguard the property rights of the original resource with international conventions, while at the same time developing higher-yielding and disease-resistant varieties through genetic improvement.

THREAT FROM SYNTHETIC SUBSTITUTES

Cheaper synthetic substitutes have always threatened markets for NWFPs. However, the long-term effects of synthetic drugs and the development of resistance by pathogenic parasites to synthetic drugs have weighted the scales on the side of natural NWFPs. More and more R&D is done through joint collaboration to study the medicinal and other uses of plants products. The resurgence of interest on naturals has resulted in more funds being allocated to this type of R&D required to reduce costs of production.

Any threat from synthetic products should be taken as a challenge for vigorous R&D work to improve the economic competitiveness of the product. In the essential oil industry, the survival of many essential oils and flavour industries is largely due to intensive research on breeding new and better oil yielding varieties, improvements on agrotechnology and post-harvest technology, by-product utilization, value added product development, new formulations resulting in improving their competitiveness vis a vis synthetic substitutes.

Pine oleoresin and its two main products, the rosin and turpentine oil, afford another excellent example of an industry that survived and co-exists with its petrochemical-based synthetic competitors, synthetic resins for surface coating industry and mineral turpentine as a solvent and thinner in paint industry. Through sustained research on chemical modification of natural resin and development of natural resin based derivatives like hydrogenated resins, disproportionated resins, alkyd resins and melamised resins, the natural resin retained a place of its own in the surface coating industry. Similarly, research and development on natural turpentine, elevated it from the position of a cheap solvent and thinner to a valuable chemical feedstock for the manufacture of perfumery chemicals and a wide range of pesticides.

FUTURE PROSPECTS FOR PROCESSING OF NWFPs

New drugs represent a potentially valuable source of NWFP income. New product development is focused on the substitutes for synthetics that are going out of favour and new curatives for chronic diseases such as arthritis, rheumatism, asthma, allergies.

As mentioned above, agreements between the country of origin of plant resources and the R&D institutions in developed countries should guarantee that a portion of profits from newly developed drugs revert to the source country. A more important role has to be played by the scientists in developing countries in participating in joint research programmes leading to the discovery of new drugs. Though this appears to be a long shot financial benefits accruing from such work could be substantial.

New markets should be identified for expanded production, for example in the area of green products. Production of stable, low volume, high value products which can be stored for long periods pending market fluctuations will be advantageous.

Regulations governing the registration and import of processed NWFPs to Europe and USA are being reviewed and a somewhat relaxed set of regulations is expected. This could open up markets for useful and safe NWFPs from developing countries. The proposed European monographs on herbal medicines and raw materials now being developed by the European Scientific Cooperative for Phytotherapy (ESCOP) would make it easier for developing countries to process the NWFPs to comply with these specifications.

Another area that is opening up is that of "Alternative Medicine". Many societies have been formed to promote this sector and simplified registration procedures are expected. Oral and external use medicines can be sold without claims or indications. This level of registration will need proof of only their safety and quality control of production and not evidence of efficacy. This opening can be exploited by the already established herbal medicines used in systems like Ayurveda and Chinese medicines.

An increase in the number of herbal products in pharmacies of developed countries is a testimony to a growing demand for these products. Studies have shown that the cost factor has little or no effect on the sales and that the trend for herbal medicines in Europe is increasing. As a result opportunities for collaboration with developed countries are increasing and joint venture projects for R&D are expected to increase.

It has to be emphasized that the future of these products will also depend on advertising and packaging, in addition to conformation to specifications. In consumer-oriented societies, attractive and safe packaging is as important as the quality of the product.

RECOMMENDATIONS

The recognition and the will of governments to implement multiple use forestry programmes are essential for the development of sustainable utilization of NWFPs. The forest management policies and plans should consider timber and NWFPs as complementary in the use of forests for economic gain, while conserving the forests and their biodiversity.

Decisions on the scale of exploitation of NWFPs from wild sources have to be based on accurate inventories of plant resources, and the feasibility of sustainable harvesting. Planting programmes should consider medicinal and aromatic plants as a priority for industry development, as niche markets for these products already exist.

Information on the Resource Base

A thorough understanding of the resource base is absolutely necessary before a country can plan development of industries based on NWFPs. Hence it is necessary to:

identify all the important NWFP resources which are used or required by local communities or needed by trade and industry within the country or for export. This exercise should be conducted with participation of local user collectors and representatives of trade and industry.

compile all information on NWFPs according to their use and prioritise items which provide substantial social benefits and/or large volume internal or export trade as raw material for industry, including information on use and value of exported species.

Policy Issues

In addition to other policies that demonstrate a commitment to NWFP resources as a means of employment generation, governments should enact the following processing-related policies:

Facilitate free market economic policies by removing bureaucratic controls and other restrictions.

Reform regulatory and legislative controls on processed NWFPs such as medicinal products manufactured according to indigenous pharmacopoeias in a manner conducive to the development of industry.

Include essential oil and other NWFP production into afforestation and reforestation projects and other agroforestry programmes.

Research and Development

The necessary inputs in terms of infrastructure and facilities should be provided to encourage R&D necessary for the development of the industrial processing of NWFPs. The following activities should receive the urgent attention of governments and other donor agencies:

R&D on process and product development. Appropriate technology adaptable at forest or rural locations.

Development of downstream processing to produce value added products.

Strengthening of R&D institutes including provision of pilot plant processing facilities for testing viability and for training personnel.

Setting up facilities for design and fabrication of process equipment for appropriate technology as well as pilot plants for scale up operations.

Develop indigenous scientific and technological capabilities in industrial utilization of NWFPs by training overseas.

Marketing

As mentioned earlier, marketability will be a crucial factor in determining the failure or success of industries. For local markets, user industries should be promoted so that locally produced NWFPs can be used to save foreign exchange needed for importation of such additives. Further processing to yield value added products will be limited by the local demand situation unless they could be produced at prices to be competitive in the world market. Even if the cost of production is low and quality of the products are good, it will be difficult to enter the protected world market.

In terms of improving market outlets, the following activities are recommended:

conduct feasibility studies for new ventures in terms of investments, marketability, sustainability, and economic viability, and potential for joint ventures.

increase entrepreneurs' awareness about the potential of NWFP industrial processing through workshops, symposia and exhibitions.

promote trade through visits to brokers/buyers and participation in trade fairs, etc.

Financial and Infrastructural Support

Establishment of small-scale industries based on NWFPs in rural areas needs financial resources and other infrastructural support. Plans for such projects should include funding from governments and other aid organisations and international development agencies. Funds earmarked for such development projects should be disbursed under proper supervision to make sure that maximum benefits are obtained. The involvement of farmers, government officials, NGOs and other agencies on a day to day basis will ensure the proper implementation of such projects.

Private entrepreneurs can be attracted to invest in rural industries by improving the accessibility to the sites of NWFPs, and by providing easy access to credit and tax incentives. Extra funds should be allocated for appropriate institutional development and R&D needs of agroforestry and appropriate process technology to assist speedier realization of potential benefits achievable by the NWFP utilization. The papers by Sène, Arnold, and Pswarayi-Riddihough and Jones discuss in more detail the financial resources and other infrastructural support needed for NWFP ventures.

It is hoped that governments will give serious consideration to the above and provide legislative, financial, administrative and other support to enhance transfer of technology, human resource development, and establishment of industries based on NWFPs.

Governments should join forces with international organisations and donor agencies to provide technical assistance and support for the management, conservation and development of forests.

REFERENCES

Anand, Nitya. 1993. Factors having a bearing on the industrial utilization of medicinal plants for the production of plant based medicines. Report. Geneva, UNIDO.

Anon. 1954. Natural plant hydrocolloids. Advances in Chemistry Series 11, American Chem. Soc.

Anon. 1986. Status report on prominent tree-borne oilseeds. Jammu, India, Regional Research Lab.

Anon. 1993. Proceedings of the workshop on non-timber forest resources. Economic Botany 47:215-290.

Atal, C.K. and Kapoor, B.M. 1982. Cultivation and utilization of medicinal plants, Part I. Jammu, India, Regional Research Laboratory.

Atal, C.K. and Kapoor, B.M. 1982. Cultivation and utilization of aromatic plants, Part II. Jammu, India, Regional Research Laboratory.

Balick, M.J. 1979. Amazonian oil palms of promise: a survey. Economic Botany 33:142-128.

Bennet, S.R. et al. 1991. Food from forests. Dehra Dun, India, Indian Council of Forestry Research and Education.

Bielenber, C. 1993. Feasibility of jatropha oil as a substitute for diesel fuel in Male. Washington, DC, Appropriate Technology International.

Bringi, V.N.V. 1988. Progress in chemistry and technology of non-traditional oil seeds. J. Oil Technologists Assoc. of India (April-June):41.

Chaudhry, D.C. 1993. Agarwood from Aquilaria malaccenis. Minor forest products news 3(4). Dehra Dun, India.

Chawla, J.S. 1987. Utilization of forest and agro-industrial residues. Holzforschung and Holzverwerchung 39:121-125.

De Silva, K.T.D. 1982. Development of drugs from plants. Proc. Sri Lanka Ass. Advmt. Sci. 38:55-71.

De Silva, K.T.D. 1993. UNIDO development programmes on industrial utilization of medicinal and aromatic plants. Acta Horticulturae 333:47-54.

Duke, J.A. 1981. Handbook of the legumes of world economic importance. New York, Plenum Press.

Dwivedi, A.P. 1993. Forests: the non-wood resources. Dehra Dun, India, International Book Distributors.

EEC. Market for herbal medicines 1990. UK, McAlpine, Thorpe and Warrier, Ltd.

FAO. 1989. Small-scale harvesting operations of wood and non-wood forest products involving rural people. FAO Forestry Paper 87. Rome, FAO.

FAO. 1994. Non-wood News 1.

George, Watt. 1966. The commercial products of India. New Delhi, Today and Tomorrow Printers (Reprint).

Godin, V.J. and Spensley, P.C. 1971. Oils and oils seeds. Tropical Products Institute, U.K.

Grainge, M. and Ahmed, S. 1986. Potential of neem tree for pest control and rural development. Economic Botany 40: 2201-2209.

Gupta, T. and Guleria, A. 1982. (Reprint 1992) Non-wood forest products in India. New Delhi, Oxford and IBH Publishing Co. Pvt. Ltd.

Hill, Albert F. 1951. Economic botany. New York, McGraw Hill Book Co., Ltd.

Humphrey, F.R. 1964. Occurrence and industrial production of rutin in S.E. Australia. Economic Botany 18(3):1964.

International Atomic Energy Agency. 1982. Improvement of oil seed and industrial crops by induced mutations. Vienna, IAEA.

ICFRE. Chir pine: a monograph. Dehra Dun, India, Indian Council for Forestry Research and Education.

Ikram, Hussain. 1978. Compendium of medicinal plants. Karachi, Pakistan Council of Scientific and Industrial Research.

Imle, E.P. 1978. Hevea rubber, past and future. Economic botany Vol. 42. New York, New York Botanical Garden.

Jain, P.P. et al. 1988. Chemical studies on oilseeds of forest origin, The Indian Forester 114.

Kerr, K. 1991. Economic potential of handicraft enterprises in rural development: focus on Indonesia. Unasylva 165, Vol. 42.

Knowles, P.F. 1967. Processing seeds for oils in towns and villages of Turkey, India and Egypt. Paper presented at 7th annual meeting of Soc. for Economic Botany, April 1966.

Lawrence, Ray V. 1972. Rosin and its derivatives. Sympine Symposium. New Delhi, India.

Laxmikantan, V. 1982. Chemistry and industry of tree borne oilseeds in service to citizens. Proc. National Seminar on Chemistry, Industry and Citizen. Dehra Dun, India, ICFRE.

McLaughlin, S.P. 1983. Biocrude production in arid lands. Economic Botany 37:150-158.

Mantell, C.L. 1949. The water soluble gums: their botany, sources and utilization. Economic Botany 3.

Martin, G. 1921. Perfumes, essential oils and fruit essences. Ludgate Hill UK, Technical Press, Ltd.

Martin Leake, H. 1975. A historical memoir of indigo industry in Bihar. Economic Botany 29:36.

May, P.H. 1991. Building institutions and markets for NWFPs from Brazilian Amazon. Unasylva 165, Vol. 42, pp.9.

Mugedo, J.Z. and Waterman, P.G. 1992. Sources of tannins. Economic Botany 46:55-63.

National Academy of Science. 1975. Herbal pharmacology in Peoples Republic of China. Washington, DC, NAS.

Negi, J.S., Prabhakar, D.B., and Chawla, J.S. 1984. Whole tree utilization: pine twigs for fibre boards. Holzforschung and Holz verwerschung 36:77-80.

Okafor, J.C. 1991. Improving edible species of forest products Unasylva 165, Vol. 42, pp. 17.

Ollson, G. 1991. Socio-economic importance of NTFP. Unasylva 165, Vol. 42, pp. 24

Princes, L.H. 1983. A new oilseed crop. Economic Botany 37:478-492.

Rembert, D.J. 1979. The indigo of commerce in colonial North America. Economic Botany 33:128.

Sharma, O.P. 1984. Chemistry and technology of catechu and kutch. Dehra Dun, India, International Book Distributor.

Shiva, M.P. et al. 1988. Role of eucalyptus in agroforestry and essential oil production potential. Indian Forester 114 (11).

Singh, B. 1988. Effect of removal of pine needles from the forest floor. Indian Forester 114: 761-769.

Soni, P.L. 1991. Carbohydrates. Dehra Dun, Surya Publications.

Sukh, Dev. 1978. Rural development: outline of an approach. J. Sci. and Industrial Research 37:391.

Tangley, Laura. 1993. Marketing biodiversity products: the Tagua Initiative. Washington, DC, Conservation International.

Tcheknavorian, Asenbauer and Wijesekera, R.O.B. 1982. Medicinal and aromatic plants for industrial development. UNIDO report, IO.505 3, June 1982. Geneva, UNIDO.

Tewari, D.N. 1994. Tropical forest produce. Dehra Dun, International Book Distributors.

Tewari, D.N. 1993. Non-timber forest produce in poverty alleviation. The Indian Forester 199:959-964.

Trease, G.E., and Evans, W.C. 1983. Pharmacognosy. U.K., Bailliere Tandall.

UNIDO. 1981. Report of the Workshop on Essential Oil Industry, Lucknow, India.

UNIDO. 1991a. Report of Second UNIDO Workshop on Essential Oil Industry, Manila, Philippines.

UNIDO. 1991b. Design options for a polyvalent pilot plant for the distillation and extraction of medicinal and aromatic plants

UNIDO. 1994. Development programmes on the industrial utilisation of medicinal and aromatic plants. Report. Geneva, UNIDO.

Wickens, G.E. 1991. Management issues for development of non-timber forest products. Unasylva 165, Vol. 42, pp.3.

Wijesekera, R.O.B. 1992. Practical manual on the essential oils industry. Geneva, UNIDO.

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