响应面法优化超声波辅助清洗无核绿葡萄干工艺

针对葡萄干加工企业清洗无核绿葡萄干后无核绿葡萄干极易褐变的问题,采用超声波辅助清洗工艺,在单因素实验基础上,选择清洗剂酒精度、清洗温度和清洗时间为影响因子,褐变指数BI值为指标,通过响应曲面法设计和分析,最佳清洗条件下清洗的葡萄干用热泵干燥。实验表明无核绿葡萄干超声波辅助清洗工艺的最佳条件:清洗剂酒精度44%vol、清洗温度9 ℃、清洗时间90 s,在此条件下,无核绿葡萄干BI值仅为33.43,较传统自来水喷淋清洗降低26.98%。热泵干燥葡萄干的最佳温度是50 ℃,无核绿葡萄干BI值仅为23.69,略低于未清洗无核绿葡萄干,较相同温度下热风干燥降低28.52%。

Optimization of Ultrasonic-assisted Cleaning of Seedless Green Raisins by Response Surface

Aiming at the problem that seedless green raisins easily browned by raisin processing enterprises, the ultrasonic-assisted cleaning process was adopted. Based on single factor experiments, the alcohol content, temperature and time of the cleaning agents were selected as the influencing factors, and browning index BI value was as the index. The response surface method was designed to obtain the optimal conditions for the ultrasonic-assisted cleaning process of seedless green raisins. The raisins cleaned under the best cleaning conditions were dried with a heat pump.The results showed that the optimal condition were alcohol degree 44%vol, temperature 9℃, and time 90 s. The BI value of seedless green raisins was only 33.43, which was 26.98% lower than that of traditional tap water spray cleaning. The optimal temperature for heat pump to dry raisins was 50℃. Under these conditions, the BI value of seedless green raisins was 23.69, which was slightly lower than the unwashed seedless green raisins for 28.52% at the same temperature.