Minor Constituents and Phytochemicals of the Kernel

Abstract Corn is an important source of minor essential nutrients and phytochemicals known to enhance health and prevent chronic diseases. Besides carbohydrates, protein, and fat, the corn caryopsis contains significant amounts of most B-vitamins, provitamin A, tocopherols (vitamin E), and essential macro- and microminerals. White, yellow, specialty (i.e., pigmented, high-carotenoid), and nutritionally enhanced GMO corns vary in the amounts of these important compounds. Yellow corns provide significant amounts of β-carotenes or provitamin A and xanthophylls, which prevent blindness and macular degeneration. Blue or purple corns contain important amounts of anthocyanins, antioxidants that diminish the incidence of chronic diseases. The bioavailability of phosphorus, iron, zinc, and copper is questionable due to the presence of phytic acid. In addition, corn is practically devoid of calcium, so people who depend on this cereal are more prone to develop anemia, stunt growth (infantilism), and osteoporosis. Whole corn contains relevant amounts of nutraceuticals such as phenolics (ferulic acid), flavonoids (anthocyanins), arabinoxylans, phytosterols, phospholipids, and policosanols. The majority of these compounds are antioxidants which prevent oxidative stress, considered the causal of > 60% of the deaths experienced worldwide. Most of these phytochemicals are associated to the pericarp, germ, and aleurone layer, which are usually removed during dry-milling or nixtamalization procedures.