茶树精油熏蒸处理保鲜草莓的工艺优化

Optimization of tea tree oil fumigation for keeping quality of harvested strawberry fruit

为了获得茶树精油熏蒸处理进行草莓防腐保鲜的较佳工艺条件,采用单因素试验方法研究不同熏蒸体积分数、温度和时间对人工接种灰葡萄孢霉的草莓果实腐烂发生的影响。通过Box-Behnken设计及响应面分析获得熏蒸防腐保鲜的最佳工艺条件为:茶树精油熏蒸体积分数0.66mL/L、熏蒸温度33.3℃、熏蒸时间3.1h。按此优化条件进行验证发现接种草莓果实的腐烂指数为7.5%,实测值与模型预测值的相对误差在4.1%;将此优化条件应用于未接种的新鲜草莓果实,结果发现该处理能显著抑制果实的自然病害发生,还能减缓草莓果实失重率的上升和果实硬度、可溶性固形物、可滴定酸和花青素含量的下降。研究结果为茶树精油在草莓保鲜上的商业化应用提供参考。

In order to determine the optimum condition of tee tree oil fumigation for control disease of postharvest strawberry fruit inoculated with Botrytis cinerea, effects of three independent variables, fumigation time, fumigation concentration and fumigation temperature were investigated by means of response surface methodology （RSM） combined with Box-Behnken experimental design based on the single factor experiments. Results showed that the optimal fumigation conditions were as follows： the fumigation time was 3.1 h, fumigation concentration was 0.66 mL/L and fumigation temperature 33.3℃. Verification test showed that the decay index of inoculated strawberry fruit is 7.5%, and the relative error of the measured values with the predicted value is 4.1%. Under these conditions, natural strawberries were fumigated and stored to observe the disease and quality change. The results show that tea tree oil treatment can significantly reduce the natural decay development, meanwhile reduce weight loss and maintain higher hardness, soluble solid, titratable acid and anthocyanin content. This research can provide a reference for commercial application of tea tree oil on strawberry preservation.