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News and notes

Scientific meetings
Forthcoming meetings and workshops
Publications available
Regional training programme on food and nutrition planning


Scientific meetings

A symposium on the Common Bean Seed-coat Hardening Problem, sponsored by the United Nations University and chaired by Dr. Ricardo Bressani, was held on 26 March 1981 in Santo Domingo, Dominican Republic, as part of the 27th annual meeting of the Central American Cooperative Program for the Improvement of Food Crops (PCCMCA).

A presentation by Dr. Bressani, asserting that agricultural productivity for humans must be based on production, technological value, and nutritive value, set the frame of reference for the symposium. Just as agronomists and plant breeders have specific criteria for selection to increase production, food technologists and nutritionists also have a set of criteria for increasing consumption and acceptability or reducing losses and increasing or retaining nutritive value in food crops.

The role of common beans in increasing protein quantity and quality in diets based on cereal grains and/or tubers was explained, as were the effects of cooking on the nutritive value of common beans. Other issues discussed included the effect of the hardening of beans on their consumer acceptability and economic value. A working hypothesis was presented on the development of hard-to-cook beans and the role agronomists, breeders, and food technologists have in the problem from production, to storage, to processing. Evidence on the role played by the seed coat, about which there is a consensus among those working on the problem, was also described. Water absorption, a variable of much significance in hard seeds, depends on variety, cultural practices, moisture in the grain, and the interaction of storage conditions and time.

Most common beans in Central America and the Caribbean are produced by small farmers who in some cases are already using new varieties. Nevertheless, production has not increased over the past ten years. Some evidence exists, however, to indicate certain small increases during the agronomic year 1980. An increase in bean production will be possible only if beans are produced on larger land areas with the use of seed, cultural practices, and mechanization technology developed for the purpose. It was claimed that by doing so, the small farmer will not be excluded, since he will be able to use part of the technology

The process of marketing, distribution, and storage of beans in relation to hard-to-cook conditions was discussed by Y. de Arevalo. Small farmers usually do not have to cope with hard-to-cook beans because of their relatively small production, part of which is sold and part stored. The farmer receives about a third of the price the consumer pays, with intermediaries receiving about two-thirds, a situation disadvantageous for small producers. Governments, however, have sustained large economic losses due to hard-to-cook beans, a fact that is significant for contingency programmes. Therefore, storage conditions should be developed to reduce losses either in locally produced or imported beans. The extent of such losses for national production is not well known, and it was recommended that reliable figures should be obtained. Furthermore, it is of practical interest to separate the post-harvest loss due to hard-to-cook beans from losses caused by other factors. These concepts fall within the objectives of the UNU post-harvest technology sub-programme.

In the presentation that followed, R. Martinez explained in some detail the structure of the bean seed from early development to maturity. The initial structure is the seed coat, in which early deposition of phenolic compounds takes place, while protein, carbohydrate, and other substances are deposited inside the seed coat, giving rise to the embryo or cotyledons. Some physiological functions in certain anatomical areas of the seed are understood, while no information is available for other functions. Water absorption takes place through the seed coat and through the hilum, a process representing an important aspect of the hard-to-cook condition. Knowledge of the structure of the seed coat and cotyledons is of great importance in the understanding of the process of hardening, not only for storage purposes but for seed germination as well.

In the next paper, W. Moscoso presented evidence on the role played by Na+, K+, Ca++, and Mg++ and physic acid and the pectic substances in the process of seed-hardening. According to the evidence presented, the breakdown of the pectic substances is related to higher water uptake. During cooking, first-order kinetic reactions take place and seed-hardening reduces the softening rates. Apparently changes in physic acid, pectic substances, and interchange of monovalent and divalent cations play an important role in seed-hardening, and storage should be under appropriate conditions.

The effects of different temperatures, grain moisture, and time in different storage atmospheres (air, CO2) were discussed next by E. de Mejia. Water absorption and cooking time are affected by high storage temperatures, high moisture in grain, and air conditions over time. Evidence was presented on the decrease in polyphenolic compounds with an increase in polyphenol oxidase. There fore, it was suggested that an additional route of seedhardening may take place through polymerization of phenolic compounds in the seed coat, in addition to the other possibilities discussed previously. An atmosphere of CO2 reduces the problem, since it inhibits polyphenol oxidase activity. Storage under CO2 is used by farmers to inhibit the development of the hard-to-cook quality in their stored beans.

The information developed by various laboratories was reviewed by L.G. Elías. One theory suggests that various substances may be involved in the process of water absorption at different times. For example, the hilum is very important for up to about 6 hours of soaking, followed by the seed coat and, finally, by protein from about 12 to 18 hours. Other factors such as seed size, structure of seed coat, and carbohydrate content are also of importance. Water absorption and seed hardness are negatively correlated, but seed hardness and cooking time are not always correlated.

Polyphenolic compounds are of importance in two ways: first, in polymerization in the seed coat and, secondly, in reacting with protein, mainly in the cotyledons. In addition, other mechanisms involve mono- and divalent cations, physic acid and pectic substances, and amylose content. The lack of certain correlations, the importance of some chemical components, and the number of possible pathways were explained on the basis that the seed is a biochemically active entity rather than a static one. Multiple regression equations were used to show the significance of various influences throughout storage time.

The application of water absorption and cooking time methodology to help the agronomist and breeder was discussed by R. Luse. The techniques used have still to be correlated with other factors involved in the process; however, they have been useful in screening programs at CIAT (the International Centre of Tropical Agriculture, Colombia). Of particular interest was a short, accelerated method to measure storage changes and effects. While the other papers attempted to solve storage problems and understand the mechanisms involved, this paper presented information of value to production programmes.

Poor storage conditions have caused large lots of beans to be lost; therefore, governments have become interested in learning what can be done about the problem. To eliminate the problem of not having appropriate storage conditions for recently harvested beans, evidence was presented by M. Molina on the effects of: (i) short heat treatment either with steam or in an autoclave; and (ii) salt treatment. Both proved to be effective. hard-to-cook beans may be rendered edible by: (i) cooking with salt mixtures; (ii) extrusion cooking; and (iii) drum cooking and drying.

The processes were monitored by a variety of measurements, including cooking time, texture, gelatinization patterns, polyphenol content, lignified protein, and protein quality.

The paper by M. Mora included experimental results of thermal treatment to inhibit the hard-to-cook phenomenon and comparisons of short-, intermediate-, and long-term storage conditions based on experiments carried out in Costa Rica. In these studies cooking time was measured when 90 per cent of the beans had been cooked, compared to other studies where 50 per cent was the criterion used. Long-term storage studies have some advantages, in that effects are more evident than in short-term studies. It was proposed that proper bean storage should be effected by taking advantage of the topography of countries and their specific microclimates.

A working meeting on Advanced Degrees in Nutrition Science was held in Wageningen, Netherlands, 30 March-1 April 1981 by the International Union of Nutritional Sciences (IUNS) Committee V/8, with financial support from the United Nations University and the International Course in Food Science and Nutrition, Netherlands Universities Foundation for International Co-operation (NUFFIC). The following is a report of the proceedings of the meeting.

1. Definition of human nutrition

In order to strengthen and improve the image and prestige of nutrition science, the Committee discussed two definitions of human nutrition formulated by Dr. Stanislaw Berger:

a. Human nutrition as a process:
Human nutrition is a systematic process of taking, transforming, and utilizing nutrients or other constituents, e.g., flavour compounds from consumed foods, in order to satisfy our various needs or desires related to body growth, maintenance of life, normal functions (including physical work), or repair of all organs, tissues, and cells, as well as participating in many metabolic processes at the molecular or submolecular levels.

b. Human nutrition as a science:
Human nutrition as a scientific discipline is concerned with the relationship between food and human body during its life at molecular (sub-molecular), tissue, organism and population levels.

The Committee accepted these two definitions.

2. Needs of the undernourished:

a. Food. The basic need of undernourished people is, of course, more food. This should be not only wholesome but also available at a reasonable price. The satisfaction of this need may require government intervention in the agricultural, distribution, and financial sectors.

b. Specific nutritional needs: Where there are additional nutritional needs, e.g., the specific extra demands of pregnancy, or the need for vitamin A or for iodine in certain regions, then suitable supplementary foods or a food fortification programme will be required. Identification of the right food(s) to be fortified is essential, and care must be taken to ensure that the food supplements can be readily incorporated into the traditional dietary habits of the target population.

c. Education: The undernourished need comprehensible information and education programmes designed specifically for their situation. In particular, they should be taught which foods (including cheap, fortified, and traditional staple food mixtures) are most useful, and which foods are a waste of money.

3. Needs of the over-nourished: Even those people who are exposed to a surplus of foods need nutrition education and information. They need accurate and helpful advice on how best to reduce their calorie intake over long periods and how best to choose a nutritionally sound diet. They may also need properly formulated dietary food (e.g., foods low in sodium, low in fat, or high in fibre, as well as low in calories) to include in their diets.

General principles for the nutritional aspects of standards and guidelines

During the course of the Committee discussions, a number of general principles emerged that are outlined below. It is proposed that these general principles be considered as a foundation for the introduction of nutrition considerations into the development of food standards and guidelines.

1. Nutritional quality is an integral part of overall food quality. When the nutritional quality of individual foods is considered collectively in the context of the total diet, such considerations become a matter of food safety. For example, if the nutritional quality of a nation's food supply should deteriorate, the matter of nutritional quality becomes a fundamental public health and safety issue threatening the well-being of society.

2. Food standards and guidelines involving nutritional considerations cannot stand alone. It should be explicitly stated that such standards and guidelines are integral parts of overall food and nutrition policies and strategies, be they national, regional, or universal.

3. As pointed out above, clear recognition of the fundamentally different problems of populations consuming insufficient food and those consuming excess food is essential. Frequently these problems coexist in the same nation or region, but the approaches to resolving the problem are often very different, including the roles of standards and guidelines.

4. Given the wide variability in food and nutrient needs in different nations and regions, it is essential that these differences be considered in deciding the applicability of specific standards and guidelines to these nations and regions. Although some such approaches may be universally applicable, others may not. The uniqueness of individual nations must be considered.

5. The evolution of food standards and guidelines involving nutrition aspects should be kept in the realm of the achievable, within the framework of socio-economic and political environments that exist. It is therefore reasonable to expect that there will continue to be substantial variability in the nature, scope, and magnitude of such standards and guidelines in different parts of the world. Nevertheless, it is also reasonable to anticipate that, over time, a major degree of compatibility will evolve, particularly on those approaches focused on alleviation of major nutrition-related public health problems.

6. Food standards and guidelines are best developed and promulgated under broad enabling legislation. In addition, such standards and/or guidelines should be developed in such a manner that they provide sufficient flexibility so as not to unnecessarily impede technological innovation. Also, specification of methodology for monitoring or compliance should be provided in a manner that permits change in methods to keep pace quickly with analytical methodological improvements, particularly those that provide simplicity and lower cost.

7. Given that nutritional quality considerations involve a great multiplicity of standards and guidelines concerned with many commodities and approaches, it is important that a unifying scientific and administrative structure be established to ensure that nutritional quality considerations are, in fact, appropriately introduced and co-ordinated to provide reasonable consistency and an overview of the potential impact on the total diet and food supply.

8. Food fortification:

a. Food fortification to counteract serious and widespread deficiency problems is a highly appropriate practice. The vehicle(s) chosen must be widely consumed by the target population, even if in other settings the vehicle might be considered inappropriate; e.g., for certain countries or population groups, salt and sugar may be fully reasonable vehicles.

b. Restoration of nutrients lost in processing is an appropriate measure.

c. When substitute and/or "imitation" foods become a significant portion of national and/or regional food supplies, and when significant segments of the population consume such foods as a major portion of the diet, it becomes advisable to fortify them in a manner commensurate with the nutritional quality of the foods being replaced or imitated. There is a need for development of agreement internationally on the meaning of "nutritional equivalency" and subsequent development of equivalency guidelines.

9. Nutrition labelling serves the dual purposes of providing nutrition information to the consuming public and of being a potent mechanism for maintaining and improving the nutritional quality of individual foods themselves. It is reasonable to conclude that nutrition labelling should be basically voluntary and should be introduced gradually where it is deemed appropriate. It is best considered on a regional and/or national basis. The use of nutrition labelling should be viewed as a basic policy matter, not as a matter for incorporation into individual commodity standards. On an international basis, the development and use of nutrition labelling should be consistent with currently evolving Codex policies and programmes on the subject.

10. There are no "bad," "poor," or "junk" foods per se. There most assuredly are "bad," "poor," or "junk" diets, depending on the totality of the individual foods and how they make up the daily diet. It is important to recognize that a specific food may be considered a relatively undesirable component of the daily diet in one part of the world, whereas the same food may well be a particularly important dietary component elsewhere, e.g., when the food is a major energy source in an energy-deficient region or population segment.

11. There is a need for greater and renewed attention to minimizing nutrient losses by food processing, e.g., in the extraction of flour. The wishes and desires of society concerning foods and their quality cannot and should not be disregarded. Nevertheless, improved efforts to understand these wishes and desires better could augment the consumption of foods subjected to the minimum possible processing, with a resultant salutary effect on health.

12. Any food standard or guideline ultimately should be both enforceable and enforced. It is essential to emphasize, however, that the initiation of standards and/or guidelines may in itself provide a foundation and framework for development of food control systems and supporting legislation to improve the nutritional quality of food supplies.

13. When it is appropriate for nutritional criteria to be incorporated into food standards and/or guidelines, it is essential that the purpose of such incorporation in both food quality and public health terms be explicitly stated. It is also essential that the effectiveness of the measures instituted be monitored Such monitoring should encompass measurement of attainment of the desired quality of the individual food(s) and its public health impact.


1. The Committee recommends that all institutions, organizations, or other bodies concerned with the development and promulgation of standards and guidelines for foods should take nutritional aspects into consideration where appropriate. The general principles outlined above should be used as a guide.

2. The Committee recommends that food standards and guidelines be developed in a sufficiently flexible manner so as not to impede the introduction of new products that may be found to be desirable from the nutrition point of view. Such standards and guidelines should also be subject to prompt amendment or modification consistent with the evolution of modern nutrition knowledge.


Forthcoming meetings and workshops

Hunger and Society

Food as a Human Right. 28 September-3 October. Oslo, Norway. Convenor: Dr. W. Barth Eide, Institute for Nutrition Research, School of Medicine, University of Oslo, Blindern P.O. Box 1046, Oslo 3, Norway.

Hunger and Technology

Microbiological Contamination of Foods and Feedstuffs in International Trade. 13-16 October. Tokyo, Japan. Convenor: Dr. H. Kurata, Department of Microbiology, National Institute of Hygienic Sciences, 1-18-1 Kamiyoga, Setagaya, Tokyo 158, Japan.

Hunger and Health

WHO/FAO/UNU Expert Committee on Protein-Energy Requirements. 7-21 October. Rome, Italy. Convenors:

Dr. E.M. DeMaeyer, Nutrition Research, World Health Organization,1211 Geneva 27, Switzerland;
Dr. Z. I. Sabry, Food Policy and Nutrition Division, Food and Agriculture Organization, Via delle Terme di Caracalla, 00100 Rome, Italy;
Dr. N.S. Scrimshaw, UNU World Hunger Programme, Massachusetts institute of Technology, Cambridge, Mass.
02139 USA.


Publications available

Several publications of the recently concluded MlT-Cairo University Health Care Delivery Systems Project are now available in monograph form. Conducted between 1977 and 1980 in association with Egypt's Ministry of Health, this project addressed issues of health-care delivery in relation to malnutrition, early childhood mortality, and birth rates in Egypt. Studies available include the following:

Infant Mortality, the Birth Rate, and Development in Egypt, by John Osgood Field and George Ropes (May 1980).

The Influence of the Health System on the Recorded Incidence of Infant Mortality and Birth Rates in Rural Egypt, by John Osgood Field and George Ropes (June 1980).

Results of the Health System Questionnaire Administered by the Ministry of Health, Arab Republic of Egypt, at 132 Rural Health Centers and Units, March-April 1978: A Reference Manual (May 1980).

Childhood Malnutrition in Rural Egypt: Results of the Ministry of Health's "Weighing Exercise," by Mohamed el Lozy, John Osgood Field, George Ropes, and Robert Burkhardt (June 1980).

Supplementary Feeding in Rural Egypt: A Summary Pro file of the Health System in Action, by Robert Burkhardt, John Osgood Field, and George Ropes (June 1980).

Family Planning in Rural Egypt: A View from the Health System, by Robert Burkhardt, John Osgood Field, and George Ropes (June 1980).

Development in the Egyptian Governorates: A Modified Physical Quality of Life Index, by John Osgood Field and George Ropes (January 1979).

Copies may be obtained free of charge by individuals and organizations in low-income countries and at nominal cost by international organizations and others. Requests should be mailed to: Dr. John O. Field, Nutrition Institute, Tufts University, Medford, MA 02155, USA.


Regional training programme on food and nutrition planning

The fifth training course on food and nutrition planning is being organized by the University of the Philippines at Los Baños (UPLB), the Netherlands Universities Foundation for International Co-operation (NUFFIC), and the International Course in Food Science and Nutrition (ICFSN) in cooperation with the UN World Health Organization {WHO) and the Food and Agriculture Organization (FAO).

The course, which leads to a master's degree in professional studies, is intended for personnel from government or private institutions, universities, or international agencies involved in planning, monitoring, implementation, or teaching in the field of food and nutrition planning.

Curriculum: The main courses are on ecology of food and nutrition, food and nutrition economics, statistics, economics of agricultural development, advanced human nutrition, food and nutrition planning, communication and rural change, and food science.

Elective courses, workshops, seminars, and six weeks' field work complete the programme.

Requirements for admission: Candidates must possess a bachelor's degree or equivalent in related field and should preferably come from countries of Asia and the Pacific.

Course period: June 1982-October 1983

Place: University of the Philippines at Los Baños, Laguna, Philippines. fellowships A limited number of fellowships will be made available by the Government of the Netherlands.

Application: For further information about the course and for application forms, contact the Director, UPLB-FNP, College Laguna, 3720 Philippines. The closing date for applications is 1 December 1981.

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