Sweetpotato ranks seven among the most important food crops in the world. With high carotene content, the orange-fleshed cultivars have a great potential in combating vitamin A deficiency (VAD). Processing sweetpotato into flour would increase its shelf-life while providing good quality food during off-season. Various dehydration technologies such as hot air drying, drum drying, and spray drying have been used to produce sweetpotato flour. However, these technologies are labor intensive and time consuming. Due to the demand of sweetpotato flour as an ingredient in food processing industry, there is a need to develop more efficient dehydration technologies to produce sweetpotato flour. Sweetpotato flour processing requires washing, peeling, slicing or shredding, soaking, blanching, and drying. All these steps are associated with nutrient losses and increases in cost of production. Vortex dehydration technology® (VDT), also known as the Windhexe, was introduced by GreenShift CleanTech Corporation. This technology simultaneously pulverizes and dries any material using heated, compressed air and with this technology, food materials do not require pre-drying treatments that are usually performed for all commercially available drying technologies. This study aimed to investigate the efficacy of VDT in processing orange-fleshed sweetpotato (OFSP) into beta-carotene rich flours and evaluate the nutrient retention and physical properties of Windhexe OFSP flour as compared to the flours produced by hot air drying (HD) and freeze-drying (FD). Windhexe technology required less drying time and labor yet it produced OFSP flour at 110oC with higher nutrient retention as compared to the most commercially feasible drying technology, hot air drying.
The Windhexe achieved a significant retention of carotenoids as well as total phenolic and ascorbic acid as compared to hot air drying (p