提高冻干山药片品质的工艺优化

为改善冻干山药片的复原率、质构、色泽以及口感，对加工过程中的烫漂、浸泡液处理方案和冻干工艺进行研究。结果表明：山药片在95℃条件下烫漂60s可防褐变，并有利于后续的浸泡和冻干；用含有5% NaCl、10%葡萄糖和10%麦芽糊精的浸泡液，在30℃条件下浸泡30min，可提高复原率；较优的冻干工艺为使用带有强对流鼓风的速冻生产线在－30℃条件下对山药片冻结，采用5℃保持7h，35℃保持2h程序冻干。该工艺生产出的山药片具有较好的复原率和感官品质。

Optimal Process for Quality Improvement of Freeze-dried Yam Slices

In order to improve recovery rate, texture, color and taste of freeze-dried yam slices, crucial steps in the preparation process of yam slices such as blanching, soaking treatment and freeze-drying were investigated. The results indicated that the optimal blanching of yam slices at 95 ℃ for 60 s could prevent browning and consequently was beneficial to soaking and freeze-drying. The optimal soaking process at 30 ℃ for 30 min using soaking solution composed of 5% NaCl, 10% glucose and 10% maltodextrin could improve recovery rate. The optimal freeze-dried process was quick-freezing at －30 ℃, and then sequential freeze-drying at 5 ℃ for 7 h and 35 ℃ for 2 h. Freeze-dried yam slices obtained using the optimized process displayed better recovery and sensory quality.