Effect of Ultra-High Pressure Combined with Enzymatic Hydrolysis on the Quality of Red Jujube Juice

Five different pressures were used to prepare red jujube juice based on ultra-high pressure (UHP) re-enzymolysis, enzymolysis re-UHP and enzymolysis only. Combined with bionic equipment such as electronic tongue, electronic nose and colorimeter and multivariate statistics, the sensory quality of 33 red jujube juice samples was evaluated. The differences were analyzed by principal component analysis, canonical correspondence analysis, cluster analysis, redundancy analysis and multivariate variance analysis. The above analysis methods showed that UHP re-enzymolysis and enzymatic hydrolysis re-UHP had more influence on the quality of red jujube juice than pressure, and the overall quality of red jujube juice after UHP treatment was close, and there was a significant difference in sensory quality between the two groups and enzymatic hydrolysis only (P<0.001). Redundancy analysis proved the difference was mainly caused by flavor indexes such as aromatic substances, alkanes and sulfides, and the quality of jujube juice prepared by UHP after enzymolysis was better. Meanwhile, it was found that UHP treatment was helpful to improve the non-biological stability of jujube juice. Therefore, UHP treatment can obviously improve the quality of jujube juice.