| Food and Nutrition Bulletin Volume 1, Number 1, 1978 |
|Interfaces of agriculture, food science and nutrition|
A summary of the proceedings of a UNU-IRRI workshop
The second of a series of workshops was held from 28 February to 3 March 1977 at the International Rice Research Institute (IRRI), Los Baños, Laguna, Philippines. Sponsored by the UN University and the IRRI, and with partial financial support from the Rockefeller Foundation, the workshop brought together 34 multidisciplinary experts from East and Southeast Asia and other regions of the world.
Opening ceremonies were followed by a plenary session with three major presentations on "Malnutrition, Food Patterns, and Nutritional Requirements in Southeast Asia", the "Status and Potential of Food Production in Asia", and the "Status of Food Science and Potential of Food Processing in East and Southeast Asia". The presentations were followed by a detailed discussion. Four half-day workshops were held on the following topics: Nutritional Value of Foods; Losses in the Rice Post-Production System in some Southeast Asian countries; Nutrition Goals for Agriculture, and Goals for Sector Planning and Nutrition Planning. A brief summary of the discussions and recommendations follows; the complete report is in press.
1. Food Production, Use, and Nutritive Value
Rice is the principal staple in many areas of Southeast Asia, but it is frequently supplemented by others such as sweet potatoes, cassava, or corn. Selective breeding of rice to increase its protein content from 7 to 9 per cent, without sacrificing yield and grain quality, would far outweigh gains made by raising the protein quantity of cassava. Increasing the protein content of the cereal staple may make it possible to increase the proportion of cassava in the diet. Where it is plentiful, the use of cassava as a substrate for the growth of unicellular microorganisms to yield single-cell protein products for animal feed should be considered.
The prospects for improving the carotene content and protein quality of the sweet potato by selective propagation are good. In Indonesia, where much cassava is now eaten, the sweet potato is being promoted as a substitute because it is nutritionally superior. Corn, too, should have an important place in the Southeast Asian diet, because, in addition to energy, it supplies substantial amounts of protein and carotene.
The need to encourage greater consumption of legumes in the rice-based diet was stressed at the workshop. The major constraint to the production, particularly of soybeans and mung beans, is their low yield in Southeast Asia, a fact related to the problem of nitrogen fixation. The possibility exists of selecting mung bean lines with a lower phytate and zinc content. This is relevant to iron and calcium utilization, but the problem of phytate is not significant in mung bean sprouts. Four-angled beans-a hardy legume-can be grown easily in most backyard gardens. It was noted that the young pods, now commonly eaten, have a much lower protein content than do the dry seeds. The tubers and leaves of four-angled beans are also rich in protein, and this is an area for further exploration.
Fats and oils can make up for the deficit of calories in Southeast Asian diets, and their greater use also serves to reduce the bulk of food that must be eaten. Refined palm oil, which is comparatively more unsaturated (linoleic acid content about 10 - 11 per cent of total fatty acids) than the highly saturated coconut oil, is now gaining wide acceptance as a cooking oil in Malaysia, and its use has spread to neighbouring Thailand. There is a need to blend the highly saturated coconut oil with 10 - 15 per cent vegetable oils rich in polyunsaturates, such as soybean or corn oil, if the oil is used in a food that is more or less the sole food for a group, e.g., a milk product fed to infants. In Burma, the potential for increased consumption of sunflower seed oil is good. The selection of edible oils should be examined for their content of essential fatty acids as well as for their energy-yielding potential.
Table 1 Foods that should be promoted
|Foods||Type of promotion needed|
|Cereals other than rice||+||+|
|Oil (such as coconut and peanut)||+||+|
|Legumes: soybean, mung bean, peanut and cowpea||+||+|
|Meat (pork and/or beef)||+||+|
|Foods as a Source of Iron/Carotene|
|Green leafy vegetables (spinach, swamp leaves,|
|water convolvulus, etc.)-identify indigenous||+||+|
|vegetables rich in vitamin A and/or iron, that should|
|Fruits (avocado, papaya, orange)||+||+|
The iodization of salt should be extended to all countries where endemic goiter exists. The choice of a vehicle for iron fortification in this part of the world was discussed. In Central America, sugar has been successfully fortified with vitamin-A palmitate with no effect on flavour. The wide use of monosodium glutamate in Southeast Asia may render it a useful vehicle for vitamin-A fortification.
The desirability of selective breeding of vegetables with low exalate content was also discussed. This is relevant to full utilization of calcium, iron, and zinc.
Greater efforts should be directed toward fish breeding in fishponds, a matter which has become urgent because in many areas marine fish supplies are dwindling due to overexploitation.
The processing of weaning foods using indigenous ingredients should be given a high priority by food scientists. Practical measures for the prevention of mycotoxins in crops that are stored at high-moisture content should be given urgent attention by food scientists.
Foods recommended should be inexpensive, readily available, and already acceptable. Regional differences exist in eating habits and food preferences. The above table lists nutritious foods that should be promoted to satisfy the common nutrient deficiencies in the region-calories, protein, and vitamin A.
Special educational and promotional campaigns are required to increase the production and consumption of nutritious foods. Promotion of breast-feeding should be encouraged in all educational activities.
Discussing the potential contribution of food science toward making processed foods more nutritious, it was considered that noodles, snack goods, and beverages could be enriched with proteins and vitamins without sacrifice in consumer acceptability.
A nutrition component in agriculture is a relatively new concept in the region. Food production needs to be increased by agriculturalists through better plant-breeding and agricultural techniques. Food scientists can help by processing excess crop yields and thereby reduce post-harvest losses. The use of cheap and simple village-level food-processing technology and locally made equipment could provide inexpensive, acceptable food products throughout the year. Multiple cropping needs to be encouraged to add diversity of food to the diet in order to supplement nutritional deficiencies in the staple crop.
2. Post-Harvest Losses
It was estimated that food losses during harvesting and post-harvest amount to 10 - 37 per cent for rice and may reach as high as 50 per cent for vegetables and fruits. Nutrient losses and/or toxicity are associated with the presence of moulds in grains, oilseed meals, and roots and tubers. Nutrient losses are also caused by improper home storage and cooking practices. Losses are also incurred during metabolism after consumption of an unbalanced diet.
Adequate marketing information should be systematically provided to farmers in the agricultural production system to ensure appropriate supply and demand, especially for vegetables and fruits. Facilities for training in the home, farm, or community in processing of certain fruits and vegetables, using suitably modified traditional methods of preservation such as drying and pickling, should be encouraged. Nutrition education for balanced diets for all classes and ages should be promoted, and proper food-handling and preparation methods taught, to ensure efficiency in utilizing the available food supply. Education of farmers should include topics such as the effects of moisture content and bruises or injury on nuts and oilseeds in relation to insect and/or fungal infestation, particularly by aflatoxin.
A systematic survey should be conducted in the various countries of Southeast Asia on the nature and actual extent of physical as well as nutrient losses of the various grains, green leafy vegetables, fruits, legumes, and tubers. Studies should also be conducted on specific post-harvest handling and transport practices and utilization in relation to losses from these agricultural products. At the same time, personnel should be trained in the use of available post-harvest technology, especially for the preservation of fruits and vegetables. The feasibility of establishing small-scale food-processing centres located on the farms themselves should be explored. This is one practical way of minimizing losses of fruits and vegetables and legumes during transit to urban areas, and of making these foods available throughout the year.
The feasibility of using small domestic animals for the effective utilization of damaged and/or deteriorated cereals, legumes, fruits, vegetables, and oilseeds should be explored. Handling characteristics should also be taken into account in plant-breeding research, particularly for some fruits and vegetables.
Some of the problems associated with food production in this region are as follows.
(a) Attention is being concentrated solely on rice production; only in recent years have efforts been directed toward other foods.
(b) There has been a lack of technology available that could be incorporated into the cropping system.
(c) Agricultural technology has favoured large growers and is not suitable for small farmers.
(d) Agriculture has been export-oriented; food for domes tic consumption must receive far greater emphasis.
(e) Too many farmers are landless.
(f) Marketing and distribution of food are inefficient.
(g) Huge post-harvest losses of food occur because of insects, mould, and simple spoilage.
(h) There has been little encouragement of the production of nutritious foods.
(i) Both producers and consumers have lacked knowledge of what constitutes good nutrition.
3. Recommendations for Possible Solutions to the Problems Outlined Above
(a) Government incentives and efforts should be directed toward improving the economics of producing nutritious foods, including improved yields of legumes and other protective foods. However, these must be combined with measures to increase the food-purchasing power of the poor. A better-fed population will eventually increase effective demand and improve purchasing power. At present, agriculturalists are basically supplying effective demand, and this is usually less than the consumer's nutritional needs.
(b) Animal husbandry should be promoted to help meet human requirements for animal protein within the framework of developing-country economies. Ruminants should be grass-fed, or should consume vegetable wastes to the maximum extent feasible. Similarly, non-ruminant feeding should minimize the use of food consumed by humans. The practice of using grain largely for animal feed, characteristic of many industrialized countries, is not appropriate in developing countries.
(c) In line with increasing the importance of nutrition in national development, national and international agricultural research centres should give greater priority to commodities that may have lower economic value but that are important for improving the diet of lower-income populations.
(d) Nutritionists should recommend ways in which food scientists can help agriculturalists to achieve these nutrition & goals. This means that food preservation and packaging methods should be improved, with emphasis on food processing at the village level, to make use of simple, locally available technology. Simple, acceptable, convenient, and nutritious processed foods should be developed at the lowest feasible cost. Examples are vegetable-protein mixtures and dried fish-cereal mixtures for use as weaning foods.
(e) Expensive and imported foods should be displaced by local or cheaper indigenous food crops. Examples include soy products and legumes in place of meat, and flour from roots and tubers or coconut meal to replace imported wheat for bread.
(f) Nutrition education should be given emphasis at all levels of society in order to inculcate good eating habits in all age groups.
(g) Closer co-operation among agencies involved in agriculture, nutrition, and food science is needed, and should be further promoted nationally, regionally, and internationally.