NUTRACEUTICAL POTENTIAL OF NATIVE MAIZE AND CHANGES DURING TRADITIONAL AND EXTRUSION PROCESSING

One of the legacies of Mesoamerican cultures is reflected in maize (Zea mays L.) landrace varieties used in Mexico. With the exception of Antarctica, maize is currently grown on all continents of the world, with global production exceeding 844 million tons. Maize landraces contain genes which impart genetic variability of utmost importance. Within these accessions there are maize landraces with modifications in grain color and pigments, which have unique phytochemical properties. There are two main families of pigments associated with corn, phenolic-derived pigments, which include anthocyanins, and carotenoids. The carotenoid-rich maize is widely grown in the world, while the genotypes rich in anthocyanins are planted only in very limited areas. Anthocyanin-rich corn can be considered as nutraceutical because these pigments have preventive effects against oxidative stress, chronic degenerative diseases and cancer. Other important phytochemical are phytosterols and policosanols which have hypocholesterolemic effects. Importantly, all native corn materials contain phenolic compounds of high value, so maize landraces constitute a reservoir and genetic heritage to be explored. This review describes the main phytochemicals associated with corn, with emphasis on native varieties, and also presents the nutraceutical properties of native corn tortillas processed by traditional processing and emerging technologies such as extrusion, and their involvement in food and health.