枣酱主要加工阶段工艺优化及其品质分析

Optimization of Process of Jujube Sauce in Main Processing Stages and Analysis of Its Quality

为确定枣酱加工阶段条件(软化、浓缩、杀菌),该研究以残次骏枣为主要原料,以枣酱产品的色差和总抗氧化能力为评价指标,利用单因素试验和响应面Box-Behnken设计试验优化枣酱加工阶段条件,探究最佳加工阶段样品的品质变化。结果表明,软化阶段的最佳条件为软化温度55℃、料水比1∶4(g/mL)、软化时间3.15 h;浓缩阶段的最佳条件为柠檬酸添加量0.6 g和浓缩温度70℃;杀菌阶段的最佳条件为杀菌温度90℃和杀菌时间17 min。在此条件下,枣酱产品的色差为64.19,总抗氧化能力为7.22 U/L。主要加工阶段样品的总酸、维生素C、总酚、总黄酮等的含量与抗氧化能力差异显著,同时相关性分析表明可溶性固形物、维生素C、总酚、总黄酮等的含量与抗氧化能力之间具有极显著正相关关系(P<0.001)。基于主成分分析可将15个品质指标简化为2个主成分,累计方差贡献率达93.69%,枣酱的综合评分最高,为1.55。综上可知,该研究可为阐明枣酱加工过程中的品质变化和枣酱工业化生产提供理论参考。

In order to determine the processing stage conditions(softening,concentration and sterilization)of jujube sauce,in this study,with defective Ziziphus jujuba Mill.cv.Junzao as the main raw material,color difference and total antioxidant capacity of jujube sauce as the evaluation indexes,single factor test and response surface Box-Behnken design test are used to optimize the processing stage conditions of jujube sauce,and the quality changes of samples in the optimal processing stage are explored.The results show that the optimal conditions in the softening stage are softening temperature of 55℃,solid-liquid ratio of 1∶4(g/mL)and softening time of 3.15 h.The optimal conditions in the concentration stage are citric acid addition amount of 0.6 g and concentration temperature of 70℃.The optimal conditions in the sterilization stage are sterilization temperature of 90℃and sterilization time of 17 min.Under these conditions,the color difference of jujube sauce products is 64.19 and the total antioxidant capacity is 7.22 U/L.The content of total acids,vitamin C,total phenols,total flavonoids and the antioxidant capacity of the sample in the main processing stages are significantly different.Meanwhile,correlation analysis shows that the content of soluble solids,vitamin C,total phenols and total flavonoids are very significantly positively correlated with antioxidant capacity(P<0.001).Based on principal component analysis,15 quality indexes could be simplified into 2 principal components,the cumulative variance contribution rate is 93.69%,and the comprehensive score of jujube sauce is the highest of 1.55. In conclusion, this study can provide theoretical references for elucidating the quality change of jujube sauce during processing and industrial production of jujube sauce.