低温等离子体处理蒜片减菌工艺优化及品质变化

Cold Plasma Process Optimization for Bacteria-reducing Treatment of Garlic Slices and Their Quality Changes

摘要:

为了探究低温等离子处理对脱水蒜片减菌效果及品质变化，以减菌率为主要指标，色差为参考指标，分别对处理时间（min）、处理高度（cm）、装载量（kg/m2）三个因素进行单因素实验。进一步以减菌率作为响应值，开展响应面试验设计，得到最佳减菌处理工艺，并测定低温等离子体处理前后大蒜素含量及挥发性风味成分。结果表明，影响因素排序为：处理时间>处理高度>装载量；响应面优化及考虑实际生产后得出低温等离子体处理蒜片的最佳减菌工艺为：处理时间3 min、处理高度3 cm、装载量1 kg/m2，在此条件下减菌率为98.11%。在最佳减菌工艺下进行低温等离子体处理，色差为3.14，在可接受范围内，色差无明显变化；处理后脱水蒜片的大蒜素含量升高了31.68%；挥发性风味成分部分被分解，整体含量降低。综合认为，低温等离子体技术减菌效果明显，对品质破坏性小，为蒜片减菌工艺提供了一种新的思路与方法。

Abstract:

In order to explore the bacteria-reducing effect and quality changes of dehydrated garlic slices treated by cold plasma, with bacterial reduction rate as the main index and color difference as the reference index, single-factor experiments were carried out on three factors: treatment time (min), treatment height (cm) and loading amount (kg/m2), respectively. The response surface test design was further carried out with sterilization rate as the response variable, to obtain the optimal process for bacteria-reducing treatment. The contents of allicin and volatile flavor components before and after the cold plasma treatment were determined. The results showed the order of influencing factors as treatment time>treatment height>loading amount; after the response surface optimization and considering the practical production, the optimal cold plasma process for bacteria reducing treatment of garlic slices was: treatment time, 3 min; treatment height, 3 cm; loading amount, 1 kg/m2. Under these conditions, the bacteria reduction rate was 98.11%, the color difference was 3.14, and the color difference underwent insignificant change (within the acceptable range). After the treatment, the allicin content of the dehydrated garlic slices increased by 31.68%; the volatile flavor components were partially decomposed and the overall content decreased. It is concluded that the cold plasma technology exerts a significant bacteria-reducing effect while causing minimal damage to quality, which provides a new idea and method for bacteria-reducing treatment of garlic slices.