Development of low-fat and anthocyanin-rich purple sweet potato vacuum fried chips

Vacuum frying technology has proven to be one of the best methods to produce snack products with higher retention of health-promoting/protecting nutraceuticals with reduced-fat content. In this work, application and optimization of vacuum frying process for purple sweet potato have used response surface methodology-based Box-Behnken design to produce low-fat and anthocyanin-rich purple sweet potato vacuum fried chips. The study showed the significant impact of frying temperature, vacuum pressure, and frying time on the chip's moisture and oil content, level of anthocyanin, visual impressions like color and texture. The selection of optimized frying parameters was carried out using a numerical optimizer and found to be 105°C for 7.08 min at a reduced pressure of 14.79 kPa. Compared to the atmospheric deep-fried chips, the vacuum fried chips showed 86% retention of anthocyanin content and a 35.6% decline in oil content with a lower breaking force of 0.69 N. Overall, the study confirmed that vacuum fried purple sweet potato chips could be a viable option to produce snacks with high functional value to meet the current consumer demands. PRACTICAL APPLICATION: Purple sweet potatoes have the potential to produce healthy snack chips with lower fat content and higher functional characteristics when vacuum frying technology is used with optimized processing variables.