Abstract: Lotus root slices was quick boiled in four different media such as water, acetic acid, sodium chloride and sodium bicarbonate solution and as a result, acetic acid was identified as the best medium through comprehensive considering VC content and sensory score of quick-boiled lotus root slices as well as dry matter dissolution rate. Further, on the basis of one-factor-at-a-time experiments, Box-Behnken design combined with response surface methodology was used to optimize process conditions for the quick boiling of lotus root slices in acetic acid. The results indicated that the optimal quick boiling conditions were acetic acid concentration of 0.35%, temperature of 68.4 ℃ and quick-boiling time of 2.4 min. After quick boiling under the optimal process conditions, the content of vitamin C in lotus root slices was 30.185 mg/100 g fresh weight, and better eating quality was also achieved. The results of variance analysis showed that acetic acid concentration, quick-boiling temperature and quick-boiling time had significant effects on the content of vitamin C in quick-boiled lotus root slices (P＜0.01). Moreover, the cross-interactions between acetic acid concentration and temperature and between temperature and quick-boiling time also revealed a significant effect on the content of vitamin C in lotus root slices (P＜0.05).

Key words: lotus root slices, quick boiling, process, response surface analysis