ABSTRACT
Animals, including man, consume food to obtain the nutrients they need. Throughout the world there are differences in food consumption related to socioeconomic conditions, food availability, and cultural dictates. If a variety of fresh and cooked foods is consumed in sufficient quantities to meet the energy needs of the consumer, then the needs for protein and the micronutrients should be met. Having this in mind, it is surprising to learn that some people are poorly nourished, and indeed may develop one or more nutrition-related diseases. The early years of nutrition research focused on diseases related to inadequate vitamin and mineral intake. An important component of this research was the determination of the vitamin and mineral content of a vast variety of foods. The composition of these foods has been compiled by the USDA, and Table 1.1 provides web addresses to access these data sets. Several data sets that may not be available on the web can be found in this section. Table 1.2 provides the sugar content of selected foods in 100 g portions. This may be a very large serving size or a very small one, depending on the food in question. However, using a standard portion allows one to compare the sugar content of a variety of foods. Those that are very rich sources, i.e., honey or table sugar (sucrose), of course will have a very high value, yet one would not consume this much in a single food under most circumstances. Usually, one would select a portion size compatible with the need for sweetness in the particular food product. For example, one might add a teaspoon of table sugar to a cup of coffee. That teaspoon of sugar might weigh 8 grams.Table 1.3 provides information on the tagatose content of food. Tagatose is a new food additive used to reduce the amount of sugar in a food. It has a sweet taste, yet does not have the same energy value as sucrose. Other sugar substitutes are also used in the preparation of reduced-energy foods; however, data on their quantitative occurrence is not as readily available because of the proprietary interests of food producers. A list of sweeteners added to foods is provided in Table 1.5. Following this table is a list of the types of food additives that change the properties of food (Table 1.6). This table describes compounds that increase the shelf life of a class of foods, or additives that change the texture of a food. The specific attributes of individual food additives are described in Table 1.7. This table provides information on how these additives function in particular food products. Table 1.8 is a list of mycotoxins and bacterial toxins that can occur in food. The reader should also review Section 52 for an extensive description of foodborne illness. Table 1.9 provides a list of antinutrients sometimes found in food, and Table 1.10 is a list of toxic substances that can be present in food. Some of these toxic substances are added inadvertently by the food processing methods, but some occur naturally. If consumed in minute quantities, some of these toxic materials are without significant effect, yet other compounds (e.g., arsenic), even in minute amounts, could accumulate and become lethal.
