预处理工艺条件对冻干白萝卜脆片品质的影响

Effects of pretreatment conditions on the quality of vacuum freeze-dried white radish crisps

中文关键词:  白萝卜  真空冷冻干燥  磁场辅助冷冻  漂烫  护色

英文关键词:white radish  vacuum freeze drying  magnetic field-assisted freezing  blanching  color-retention

中文摘要:

      目的 考察护色、漂烫和磁场辅助冷冻对真空冷冻干燥白萝卜脆片品质的影响。方法 以白萝卜为原料进行单因素实验, 并在此基础上, 以复水比为评价指标, 选取护色剂(抗坏血酸)质量浓度、漂烫时间、漂烫温度进行三因素三水平正交实验, 确定冻干白萝卜脆片品质最佳的护色及漂烫条件。之后, 在此条件下, 考察不同静磁场强度(0、0.4、0.8、1.2、1.6 mT)对白萝卜的冻结曲线、复水比及感官品质的影响。结果 抗坏血酸质量浓度10 g/L、漂烫时间3.0 min、漂烫温度55℃、静磁场强度0.8 mT辅助冷冻处理, 可使真空冷冻干燥白萝卜脆片获得较好的品质。结论 真空冷冻干燥白萝卜脆片的加工过程中, 采用适宜的护色、漂烫工艺以及磁场辅助冷冻处理, 可有效提高产品的品质。本研究可为果蔬脆片的加工以及白萝卜的精深加工和高值化利用提供参考。

英文摘要:

      Objective To investigate the effects of color-retention, blanching and magnetic field-assisted freezing on the quality of vacuum freeze-dried white radish crisps. Methods The single-factor experiments were conducted with white radish. Based on the single-factor experiments, a three-factor, three-level orthogonal experiment was conducted to optimize the mass concentration of color-fixing agent (ascorbic acid), blanching time and blanching temperature using the rehydration ratio of white radish crisps as the evaluation index. In addition, the effects of different static magnetic field intensitiess (0, 0.4, 0.8, 1.2 and 1.6 mT) on the freezing curves, rehydration ratio and sensory evaluations of white radish crisps during freezing were also investigated. Results The vacuum freeze-drying of white radish crisps could obtain good quality by pretreated by 10 g/L of ascorbic acid concentration, 3.0 min of blanching time, 55℃ of blanching temperature and static magnetic field-assisted freezing with 0.8 mT intensity. Conclusion During the processing of vacuum freeze-dried white radish crisps, the suitable pretreatment process including the concentration of color fixative, blanching time, blanching temperature and magnetic field-assisted freezing can improve the quality of products effectively. This study can provide a reference for the processing of fruit and vegetable crips, and intensive processing and high-value utilization of white radish.