热空气和茉莉酸甲酯复合处理保鲜枇杷的工艺优化

Optimization of combined treatment condition of hot air and methyl jasmonate for postharvest loquat fruit preservation

为确定热空气和茉莉酸甲酯复合处理对枇杷保鲜的较优条件,采用响应曲面法研究了不同处理条件对冷藏枇杷果实品质的影响。将枇杷果实先用不同温度热空气(35～45°C)和不同浓度茉莉酸甲酯(10～30μmol/L)复合处理不同时间(3～7h),然后转入1°C冷藏35d,冷藏结束后测定果实果心褐变指数、硬度和出汁率,并建立这3个响应值的二次多项数学模型,分析其拟合程度,同时利用模型的响应面对影响枇杷果实品质的关键因素及其相互作用进行探讨。结果表明,热空气和茉莉酸甲酯复合处理保鲜枇杷的较优条件为处理温度为38.5°C,时间为5.8h,茉莉酸甲酯浓度为16μmol/L。该复合处理可有效减轻果实的木质化败坏,保持品质,且效果要显著优于二者单独处理。这些结果为该复合处理在枇杷果实保鲜中的应用提供了依据。

In order to determine the optimum condition of hot air combined with methyl jasmonate （MeJA） for preservation of postharvest loquat fruit,the effects of different combined treatment conditions on fruit quality were investigated by using the response surface methodology （RSM）.Fresh harvested loquat fruit were pretreated with different concentrations of MeJA （10-30 μmol/ L） in hot air at different temperatures （35-45°C） for different treatment times （3-7 h）,and then stored at 1°C for 35 days.Fruit internal browning,firmness and extractable juice were measured after the storage.Three second-order quadratic equations of fruit internal browning,firmness and extractable juice were established,and the fitting degree were analyzed through RSM.The key factors and their interactions affecting the loquat quality were also discussed through RSM.The results indicated that the optimum condition for combined treatment of hot air and MeJA was that temperature was 38.5 °C,treatment time was 5.8 h,MeJA concentration was 16 μmol/L.The optimized combined treatment was more effective in inhibiting flesh leatheriness and maintaining quality than applying hot air or MeJA alone.The data obtained can provide a foundation for application of the combined treatment in loquat fruit preservation.