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DEFINITION OF INGREDIENTS

Ingredients should be described in terms of the raw materials used, the processing technique employed to produce it, and the chemical and nutritional value it should have. It should also include bacteriological quality as well as functional properties. Quality control measures should be established for purposes of meeting requirements of the product.

PRODUCT TESTING

The process of testing the product is important, particularly for those situations where the ingredients in the food are so-called "non-conventional", for example, single-cell protein. Testing involves various activities: chemical analyses and amino acid content; biological evaluation in experimental animals; supplementary effect on basic diet; storage stability; tolerance tests, and acceptability trials.

Chemical composition. Chemical composition should be tested for levels of moisture, protein, ash, crude fibre, fat and carbohydrate, and the energy value of the food should be known. It should also include acceptable maximum levels of residual antiphysiological substances.

Amino acid content. This should be part of the commodity specifications and be limited to the essential amino acids. It should indicate any amino acid limiting the quality of the product for quality control purposes.

Biological quality. Because of the difficulties of evaluating biological quality in humans, animal studies should be conducted. The laboratory rat, used in a variety of methods (NPR, NIG, NPU), is suitable for such a purpose. Testing for digestibility of the protein is also highly desirable. If non-conventional sources are used, long-term studies are recommended, Particularly if the product contains small amounts of antiphysiological substances such as gossypol in cottonseed flour. Biological evaluation should also include supplementary studies of the basic diet as a means to improve or correct any nutritional deficiencies it may have.

Storage stability. Because these products are manufactured to serve as weaning foods in urban as well as in rural areas, careful storage is essential. in the latter, environmental conditions of high relative humidity, high temperature, and exposure to the external environment make storage stability tests mandatory, as these factors may all lead to the development of caking, off-flavours, and insect contamination.

Addition of preservatives. This is sometimes desirable to reduce or avoid the development of off-flavours, losses of vitamins, or formation of substances that could induce nutritional problems.

Packaging materials. Packaging materials serve to preserve the packaged food from external physical and biological factors as well as to carry appropriate messages to the potential consumer. It is best to package a processed product rather than a raw one, since with the latter there is the danger of insect egg development within the package in addition to the rapid development of off-flavours. Insects can pierce the package material and expose the product to the external environment. Packaging materials commonly used include plastic, paper with an internal covering of plastic cellophane, or closed paper boxes.

Acceptability tests. These could be carried out for periods of two to four months in schools or other institutions or directly in households.

INDUSTRIAL PRODUCTION

Once the above problems have been solved, methods of production should be established. If the materials are already processed, the production operation will involve only mixing and packaging. On the other hand, if the products are not fully processed, or are still raw, processing must be carried out. Various options are available. One is drum drying, often used for baby food products in developed countries; extrusion cooking seems to be the preferred technology today, and finally, spray drying is sometimes appropriate. There are various other possibilities, depending on specific situations. For example, if one of the ingredients is raw it can be roasted and then ground, or extruded and ground and then mixed with the already processed ingredients. Table 6 illustrates processing and marketing of some successful products.

The investment in processing is one of the most important considerations for developing weaning foods in developing countries because of the high cost. However, alternatives are available.

1. Unused national industrial capacity. Unused industrial capacity may exist in the cereal milling and processing industry as well as in other food industries. For example, there is a situation in which a spray dehydration plant has a larger capacity to produce powdered milk than it actually produces because raw milk production is not sufficient. Hydrolyzed cereal flours can be mixed with liquid milk and processed together. Soy milk and cow's milk could be combined in a similar fashion.
2. New industrial development. Such industries have been developed, but, as indicated previously, they need a large capital investment.
3. Quality control. A very important aspect in the industrial production of weaning foods is quality control, which should be integrated with the actual production of the food.

TABLE 6. Selected Weaning Food Case Studies

MARKETING

The final action is marketing of the product. There are various ways that have been tried or are now under way. One is the distribution of the product by governments in various nutritional programmes they may have. The products are either produced by government agencies or by private industries who sell them to the government. A second approach is private production and marketing in the free market, or part may be purchased by the government and part may be released to the retail market. The cost of the product is an important consideration, for both markets must be satisfied. In any event, the marketing of the product should be done with demonstrations applicable to the conditions in developing countries. The product should be advertised by the press, radio, and television. Home economics extension work to educate consumers is essential.

Some guidelines for advertising are:

Advertisement of the product should be carefully planned, taking into consideration the following points:

1. Try to give the product prestige through adequate packaging and place it in the market with other acceptable foods.
2. Run acceptability tests in the laboratory, then at an institution, with individual families, and finally at the community level.
3. Advertisement must be directed toward the specific population groups for whom the food is intended.
4. In the case of weaning foods, it is important to recognize the influence of the mother in acceptability of the product in terms of flavour and nutritional properties.
5. Run stability tests under different climatic conditions, in order to avoid undesirable changes in texture, flavour, and nutritional quality of the product in different locations.
6. Ease in preparation should be an important aspect of creating a new food.
7. Price of the product should be as low as possible to fit the purchasing capacity of the consumer, but not to make the product a food for the poor (prestige).
8. Programmes must be instituted on how to prepare the product under the conditions prevailing in the home, how to use it, and any limitations should be indicated.

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