COLORED POTATOES (SOLANUM TUBEROSUM L.) DRIED FOR ANTIOXIDANT-RICH VALUE-ADDED FOODS

Abstract

ABSTRACT Colored potatoes (Solanum tuberosum L.) are a significant source of antioxidants from polyphenols, carotenoids and ascorbic acid. In this study, the retention of total antioxidants in fresh colored potatoes and processed potato flakes prepared as potential ingredients for snack foods was studied. Total antioxidant capacity, total phenolics and total anthocyanins were higher in purple potato flesh compared with those from red, yellow and white potato cultivars. Peeled purple potatoes were blanched and dehydrated by freeze drying (FD), drum drying and refractance window drying to prepare potato flakes. Results showed no significant losses in total antioxidant capacity and total phenolic content in flakes in all drying methods obtained under study. However, 45, 41 and 23% losses in total anthocyanins content were observed in potato flakes after FD, drum drying and refractive window drying, respectively. Colored potatoes could provide an excellent source of antioxidant-rich ingredient for the production of nutritionally enhanced food products. PRACTICAL APPLICATIONS Over 50% of potato sales in U.S. are to processors for French fries, chips, dehydrated potatoes and other potato products, while the remainder goes to the fresh market. Potato consumption can be increased through the development of value-added products with enhanced nutrition. In the present study, we found that purple colored potatoes are rich in phenolic compounds that have antioxidant capacity. Different drying methods also retained the antioxidant capacity of the colored potato. Most importantly drum drying that is mostly used in potato industries to produce potato flakes retained most of the phenolic antioxidant compounds. Hence, the use of flours from colored potatoes may be used to produce products such as snack foods high in antioxidants and attractive natural colors so that the developed potato products can be marketed as healthy foods.