NFC苹果梨桑葚复合汁配方优化及其贮藏品质变化

目的 制备一款非浓缩还原(Not From Concentrate,NFC)复合汁,比较不同杀菌方式对其贮藏品质的影响.方法 以苹果梨和桑葚为原料,制备NFC复合汁,优化NFC苹果梨桑葚复合汁配方,并研究超高压(High Pressure Possessing,HPP)和热处理(Thermal Processing,TP)对复合汁贮藏品质变化的影响.结果 苹果梨汁透光率为(91.20±0.84)％,澄清度较高.按苹果梨汁的质量分数82.96％、桑葚汁的质量分数11％、柠檬酸的质量分数0.04％、白砂糖的质量分数6％复配,感官评分最高(94.70).2个处理组在贮藏期微生物指标均符合国家卫生标准要求,可溶性固形物含量和pH均无显著变化(P>0.05);离心沉淀率均显著上升(P<0.05),其中HPP处理组更低;总酚、黄酮和花色苷含量均呈下降趋势,其中HPP处理组具有更高的总酚、黄酮和花色苷含量,且能更好地保留三者含量,其中花色苷保留率均大于55％.结论 与TP处理相比,HPP处理能更好地保持复合汁品质.

Formula Optimization of NFC Apple-Pear and Mulberry Compound Juice and Change of Storage Quality

The work aims to prepare a NFC compound juice and compare the effects of different sterilization methods on storage quality. Apple-pear and mulberry were used as raw materials to prepare not from concentrate (NFC) juice. The formula of NFC apple-pear and mulberry compound juice was optimized and the effects of high pressure possessing (HPP) and thermal processing (TP) on the storage quality of compound juice were studied. The light transmittance of apple-pear juice was (91.20±0.84)%, indicating a high degree of clarification. The highest sensory score was 94.70 when apple-pear juice, mulberry juice, citric acid and sugar were mixed at the mass fraction of 82.96%, 11%, 0.04% and 6% respectively. The microbial indicators of the 2 treatment groups during the storage period met the requirements of national health standards. During storage, the total soluble solid (TSS) content and pH of both treatment groups did not change significantly (P>0.05). Moreover, centrifugal precipitation rates of both treatment groups increased significantly during storage (P<0.05), but the rate of HPP group was lower than that of TP group. The contents of total phenols, flavonoids and anthocyanins all showed a decreasing trend, but the contents of total phenols, flavonoids and anthocyanins in HPP treatment group were higher and preserved better, with the anthocyanins retention rate more than 55%. Compared with TP, HPP can better maintain the quality of compound juice.