方格星虫酶解液Maillard反应条件优化及理化特性变化

Optimization of Maillard Reaction Conditions and Changes of Physicochemical Properties of Enzymatic Hydrolysate of Sipunculus nudus

以方格星虫酶解液(SEH)为原料,以褐变度与感官评分为评价指标,通过单因素实验和正交试验设计优化Maillard反应工艺,并对Maillard反应前后色泽参数、游离氨基酸和总氨基酸含量、荧光强度进行了对比分析。结果表明:最佳Maillard反应工艺条件为半乳糖添加量4%、pH9.0、反应温度130℃和反应时间60 min,在该条件下感官评定达到13.77分。Maillard反应产物(MRPs-SEH)较SEH亮度变暗,色泽加深且更加饱满。MRPs-SEH中的17种氨基酸含量较SEH均显著降低(p<0.05)。MRPs-SEH中总氨基酸含量为279.729 mg/g,较SEH降低60.27%,其中Tyr和Met含量较SEH分别减少73.84%、72.98%,说明这两种氨基酸参与Maillard反应的程度较大,His(含量减少44.85%)参与Maillard反应的活性相对较低。MRPs-SEH中鲜味氨基酸在总游离氨基酸中的比例较SEH增加8.26%。Maillard反应改变了SEH中肽链的结构。综合来看,Maillard反应改善了酶解液的色泽与风味,为新型方格星虫调味品的开发提供理论参考。

The enzyme hydrolysate(SEH)was used as raw material,on the basis of browning intensity and sensory scores,single-factor experiments and orthogonal experiments were employed to optimize the Maillard reaction conditions,the color parameters,contents of free amino acids and total amino acids and fluorescence intensity before and after Maillard reaction were compared and analyzed. The results showed that the optimized conditions for Maillard reaction were as follows:galactose addition 4%,pH9.0,temperature 130 ℃ and reaction time 60 min,under which the sensory score reached 13.77. Compared with SEH,MRPs-SEH became darker,deeper and fuller in color. The contents of seventeen kinds of amino acids in MRPs-SEH were significantly lower than those in SEH(p<0.05). The contents of total amino acids in MRPs-SEH were 279.729 mg/g,60.27% lower than that in SEH,and the contents of Tyr and Met were 73.84% and 72.98% lower than that in SEH,respectively. This indicated that the two kinds of amino acids participated in Maillard reaction to a greater extent,whereas His(content reduction 44.85%)showed relatively low activity in Maillard reaction. The proportion of delicious amino acids in total free amino acids in MRPs-SEH was 8.26% higher than that in SEH. Maillard reaction changed the structure of peptide chain in SEH. Overall,Maillard reaction improved the color and flavor of SEH,which provided a theoretical reference for the development of new condiments of Sipunculus nudus.