小龙虾虾壳对液态酿造米醋的影响

该实验以大米为原料，在不同发酵阶段添加小龙虾虾壳，采用液态发酵工艺制备米醋，研究虾壳的添加对米醋品质的影响。通过测定总黄酮、总多酚和虾青素含量，1,1-二苯基-2-三硝基苯肼（DPPH）和羟基自由基清除率研究添加虾壳米醋的抗氧化性。采用气相色谱-质谱联用（GC-MS）仪测定虾壳米醋挥发性风味成分。结果表明，在大米糊化阶段添加虾壳，米醋品质最佳。在此条件下，制成的虾壳米醋总多酚含量为81.78 mg/L，总黄酮含量为25.05 mg/L，虾青素含量为0.315 mg/L，DPPH、羟基自由基的清除率分别为95.87%、63.10%；产生的酸类和酯类种类最多，分别为酸类4种，酯类13种。

Effect of crayfish shell on liquid-brewing rice vinegar

In this experiment, using rice as raw material, crayfish shells were added at different fermentation stages, vinegar was prepared by liquid fermentation process, and the effect of crayfish shell addition on the quality of rice vinegar was investigated. The antioxidant activity of rice vinegar with crayfish shell addition was studied by determining the contents of total flavonoids, total polyphenols and astaxanthin, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical scavenging rate. The volatile flavor components of crayfish shell rice vinegar were analyzed by GC-MS. The results showed that the quality of rice vinegar was the optimal when crayfish shells were added in rice gelatinization stage. Under these conditions, the contents of polyphenols, total flavonoids and astaxanthin of the prepared crayfish shell rice vinegar were 81.78 mg/L, 25.05 mg/L and 0.315 mg/L, respectively. The scavenging rate of DPPH and hydroxyl radical was 95.87% and 63.10%, respectively. The varieties of acids and esters were the richest, with 4 acids and 13 esters, respectively.