Abstract

Purple water yam was a good source of important nutrients and functional components. However, it is highly perishable after harvesting. In order to improve its economic value, purple water yam could be processed into formulated snack. This research was conducted at STNanotech laboratory, Soc Trang province, Vietnam in 2021 to evaluate different technical variables such as purple water yam/rice flour ratio, water incorporation, temperature/time in frying to the quality attributes of the purple water yam-based snack. Purple yam paste was mixed with rice flour at different ratios (90/10, 85/15, 80/20, 75/25, 70/30). Varying ratios of water (1018%) along with 0.5% salt and 2.0% sugar were tested for frying temperature and time in edible cooking oil (170/1.0, 165/1.5, 160/2.0, 155/2.5, 150/3.0 oC/min). Snack was evaluated for expansion, water holding capacity, hardness and overall acceptance. Results showed that ratio of purple water yam/rice flour (90/10), 14% water in blending, 170/1.0 (oC/min) of temperature/time in frying were appropriate to achieve the high expansion, water holding activity, overall acceptance and adequate hardness of snack. From snack production, the added value of purple water yam would be enhanced.