Agroindustrial project analysi

136 AGROINDUSTRIAL PROJECT ANALYSISwith the wheat germ and bran, milling decreases lysine and tryptophancontent because bran protein is richer in lysine and tryptophanthan endosperm protein. (Even before the bran and germ areremoved, wheat protein is low in lysine and tryptophan relative toother grains.) Milling also decreases the fat content of wheat products;such decrease reduces the caloric value per unit of the wheatproduct but increases the storage stability of the products againsttheir becoming rancid. British firms have used higher extractionrates for wheat (80-85 percent) with minimal change in the colorof the flour and the baking quality. 20EFFECTS OF FRUIT AND VEGETABLE PROCESSING. Fruits and vegetablescan also suffer significant losses of micronutrients during processing.The losses vary with crop, nutrient, and process. For example,the steam blanching of peas causes a 12.3 percent loss of their vitaminC content, whereas water blanching causes a 25.8 percentloss. 21 Some nutrients can be almost totally lost during canning;canned corn, for instance, loses 80 percent of its thiamin. 22PRODUCT FORTIFICATION AND MODIFICATION. When the processingfirm's choice of technology significantly affects the nutritionalquality of its product, the government or industrial associationsusually intervene to regulate the decision. The agroindustrial analystshould note such negative technological effects as nutrientlosses and attempt to minimize them by adjusting the technologyor by restoring nutrients through fortification. Food technology inthis regard is not necessarily a nutritional liability; it can enhancenutritional value by fortifying the product against nutrient lossesunavoidable in processing and by retarding spoilage or transformingpoor nutrient resources into foods of higher value. 23 Nutritionaltransformation of this kind has been the work of the Institute of20. R. J. Dimler, "Effects of Commercial Processing of Cereals on NutrientContent: Milling, Part A: Wheat," in Nutritional Evaluation of Food Processing,1st ed., pp. 197-204.21. D. B. Lund, "Effects of Blanching, Pasteurization, and Sterilization onNutrients," in Nutritional Evaluation of Food Processing, 2d ed. (1975), p. 205.22. Ibid.23. For a further discussion of fortification, see James E. Austin (ed.), GlobalMalnutrition and Cereal Fortification (Cambridge, Mass.: Ballinger PublishingCo., 1979); and Confronting Urban Malnutrition, pp. 71-75.