等离子体活化水联合介质阻挡放电处理对鲜切莴苣杀菌效果及品质的影响

李夏; 钱婧; 章建浩; 严文静

doi:10.13386/j.issn1002-0306.2023100188

等离子体活化水联合介质阻挡放电处理对鲜切莴苣杀菌效果及品质的影响

Effect of Combined Plasma-activated Water and Dielectric Barrier Discharge Treatment on the Sterilization and Quality of Fresh-cut Lettuce

摘要

摘要: 为开发适用鲜切莴苣的新型杀菌保鲜技术，本文采用等离子体活化水（Plasma-activated water，PAW）联合介质阻挡放电（Dielectric barrier discharge，DBD）等离子体技术，通过响应面试验确定最佳杀菌工艺参数，并以微生物数量、色泽、褐变度、硬度及失重率为指标，探究低温等离子体联合处理对鲜切莴苣贮藏期间品质的影响。结果表明：在PAW制备时间130 s、PAW浸泡时间5 min、DBD等离子体处理时间135 s的最佳处理条件下，鲜切莴苣表面菌落总数为（0.48±0.07） lg CFU/g。在贮藏7 d内，低温等离子体联合处理能够有效抑制微生物的生长，维持鲜切莴苣良好的色泽及硬度，延缓失重率的上升，抑制褐变的发生，有效延长货架期。

Abstract: To develop a new method for the sterilization of fresh-cut lettuce, plasma-activated water (PAW) combined with dielectric barrier discharge (DBD) plasma technology was applied in this study. Response surface methodological approach was performed to determine the optimal sterilization process parameters. Meanwhile, the microbial count, color, browning degree, firmness and weight loss rate were evaluated to investigate the effects of combined cold plasma treatments on the qualities of fresh-cut lettuce during the storage. Results showed that the total viable bacteria count on the surface of fresh-cut lettuce was (0.48±0.07) lg CFU/g under the optimal treatment conditions when PAW preparation time was 130 s, PAW soaking time was 5 min, and DBD plasma treatment time was 135 s. Moreover, during 7 days of storage, the combined cold plasma treatments could effectively inhibit the growth of microorganisms, maintain the color and firmness of fresh-cut lettuce, delay the increase of weight loss rate, and inhibit the occurrence of browning, which would effectively prolong the shelf life of fresh-cut lettuce.