Obtaining and characterization of freeze-dried whole taro root (Colocasia esculenta), mucilage and residue as functional food

Abstract

TTaro root (Colocasia esculenta L.), a starch based plant widely grown for direct consumption, has been produced for more than 2000 years in regions with a tropical climate. In Brazil, it is a crop grown by small producers, using it for direct consumption. Some industries use the tubers for preparation of baby food; however, there is no industrial processing of taro root. It contains high caloric and protein value and has elements such as phosphorus and potassium and B-complex vitamins; moreover, in popular medicine, it has recognized medicinal properties of detoxification, purification, anti-beriberi properties, etc. The purpose of this study was to determine, characterize and obtain whole taro root flour and its subproducts (mucilage and residue from mucilage extraction) by means of physical-chemical analyses, with a view toward discovering its potential qualities as a functional food. The freeze-dried flours of taro root had considerable proximate composition with lipid values below wheat flour. Starch appeared in the three types of taro root flour at significant levels. The nutritional fiber content was on average 50% greater than the daily requirements of an individual. The minerals Zn, Fe and Mn appeared at levels able to meet significant percentages of the daily needs of children, as well as the vitamin C and β-carotene content. Phytochemical compounds, saponins, anthocyanins and polyphenols were present in all the flours. As a result, we concluded that these taro root flours constitute a viable alternative to production of bakery products based on their starch content. Whole taro root flours and their subproducts may be considered as having potential for functional foods due to their vitamin, mineral, protein and phytochemical content, in addition to their expressive quantity of fiber.Key-words: chemical composition of foods, taro root flour, nutritional fiber, vitamin C, β-carotene, phytochemicals.