Variability of Minerals in Foods

Dietary guidance to the public stresses foods or food groups as specific sources of minerals such as calcium in dairy products, iron in meats and legumes, and potassium in oranges and bananas. Dietary guidance also identifies foods that are low in some minerals (such as sodium, potassium, calcium, cooper, and iron) for patients with specific disease conditions. However, the levels of minerals and other substances in foods vary because of inherent (e.g., age and species of plants and animals), environmental (e.g., animal diets, climate, soil type), and processing (e.g., fortification, food additives, cooking method) factors. the distributions of minerals in foods are not generally Gausian, but vary based on unique features of both the is affected by levels of salt added during processing and may vary from brand to brand of t he same foods, while sodium in unprocessed milk, fruits, vegetables, nuts, and meats tends to be low and stable. Iodine in milk is affected by feed supplements of iodine, the use of iodophor sanitizing solutions by the dairy industry, and the use of the iodinecontained red food dye, erythrosine. Iron and zinc in breakfast cereals are greatly affected by levels of fortification. Levels of iron, copper, and zinc in some shellfish and in liver are affected by levels of these minerals in animal diets and by the age of the animals. Some acidic foods (like tomatoes and sauerkraut) may leach minerals from metal containers with prolonged contact. formulated products (entrees, desserts, condiments) vary in their ingredients from brand to brand, and thus have different mineral composition. although it is difficult to identify all the causes of mineral variation in finished food products, it is useful to have some measure of variation (such as standard deviation or coefficient of variation) with published mean values to determine the reliability of the data.