[关键词]
[摘要]
木瓜乳中含有丰富的酶类,其中木瓜脂肪酶(Carica papaya lipase,CPL)作为天然固定化酶备受关注。目前尚无规模化制备CPL的工艺报道,限制了其在工业上的应用。本文通过板框过滤分离木瓜乳中的木瓜蛋白酶和木瓜脂肪酶,然后通过喷雾干燥规模化制备CPL,并优化了喷雾干燥的物料入口温度。在最优的入口温度135 ℃条件下,CPL的得率为4.12%,脂肪酶回收率为88.53%,比酶活为167.60 U/g。研究考察了CPL的酶学性质。结果表明,CPL水解甘油三酯的最适反应pH为9.0,最适反应温度为45 ℃。基于CPL对甘油三酯的水解特性将其作为催化剂酶解奶油制备奶味香基。感官分析结果表明制备的酶解奶油酸味和奶酪味突出,风味独特。固相微萃取-气相色谱质谱联用分析得到其酸含量为总挥发物质的73.28%。该酶制剂制备方法可以大规模高效的制备CPL,获得的CPL可以作为制备奶味香基的生物催化剂。
[Key word]
[Abstract]
Carica papaya latex is rich in enzymes, and Carica papaya lipase (CPL) as a natural immobilized lipase. Currently, there are no reports concerning large-scale preparation of CPL, which limits its industrial application. Here, a plate-and-frame filter was used to separate and extract papain and CPL from C. papaya latex, and spray drying was performed for large-scale preparation of CPL following optimization of the inlet temperature for spray drying. Results showed that CPL yield was 4.12%, total lipase recovery was 88.53%, and specific lipase activity was 167.60 U/g at an optimum inlet temperature of 135 ℃. Investigation of CPL enzymatic properties revealed that the optimal temperature and pH for triglyceride hydrolysis were 45 ℃ and 9.0, respectively. Based on the hydrolytic properties of CPL during triglyceride hydrolysis, CPL was also used as the catalyst for the lipolysis of milk fat for the preparation of dairy flavor base. Sensory analysis showed that the prepared hydrolyzed milk fat exhibited specific and prominent sour and cheese flavors. The result of solid-phase microextraction combined with gas chromatography-mass spectrometry showed that acids accounted for 73.28% of the volatiles. This enzyme-preparation method can be used for efficient large-scale preparation of CPL, with the obtained CPL as a potential biocatalyst for the preparation of dairy flavor base.
[中图分类号]
[基金项目]
东莞市产学研合作项目(东科[2014]183号)