香猪分割副产物浸提液理化特性及固定化发酵研究

Study on Physico-chemical Properties of By-products Extracts of Segmented Xiang Pigs and Their Fermented Technology Three Species of Immobilized Bacillus Cells

本实验以香猪分割副产物为原料,添加4倍的水(W/W)经高压蒸煮法反复两次进行浸提,获得香猪分割副产物浸提汁。先后考察了香猪分割副产物浸提汁和发酵产物的可溶性固形物、干物质含量、酸度、氨基态氮、胶珠细菌总数和部分样品的游离氨基酸和水解氨基酸指标,且发酵采用细胞固定化制备的地衣芽杆菌1.892、枯草芽孢杆菌1.807和发酵乳杆菌三株细菌单一或混合组合的胶珠。结果发现:高压蒸煮浸提汁及发酵产物中均含有γ-氨基丁酸(GABA),且样液中水解氨基酸和游离氨基酸中GABA含量水平分别为10.63～17mg/100g和14.97～23.05mg/100g,相关样品中γ-氨基丁酸前体物——谷氨酸含量达到195.53～245mg/100g;用2.5%的海藻酸钠、4%的CaCl2溶液硬化30min在室温条件下制备的细胞固定化胶珠能有效的发挥作用,而且6次发酵重复实验较好的指标。研究揭示浸提液和其发酵产物的水解和游离氨基酸中具有值得开发利用的γ-氨基丁酸(GABA)。

The by-products of segmented Xiang Pigs were extracted with 2 times water （W/W） by high pressure stewing method, and then this process was repeated for the filtrate residue. The two exttracts were collected together for subsequent experiments. In this study, some physicochemical indexes of the extracts and their fermented products by immobilized cells were analyzed, which included contents of soluble solid, dry matter and amino nitrogen, acidity and total bacterial count in gel bead as well as contents of free amino acid and hydrolyzing amino acid in partrial fermented products, and the single or mixture strains of three bacteria （Bacills Licheniformis 1.892, Bacillus sublilis 1.807 and Lactobacillusfermentum） were respectively selected for preparing gel beads of immobilized cells as fermententation strains. The analysis results showed that γ-aminobutyric acid （GABA） content level in the extracts and their fermented products are noticeable, the GABA levels in free and hydrolyzing amino acids ranges are respectively 14.97 to 23.05 mg/100 g and 10.63 to 17 mg/100 g respectively, and the hydrolyzing glutamic acid contents as GABA precursor range from 195.53 to 245 mg/100g in the extracts and their partrial fermented products. Under the conditions of room temperature, immobilized cells prepared by adding 2.5% sodium alginate and firming for 30 min in 4% CaC12 are favorable for obtaining better fermentation capacity, and the results of 6 repeatability experiments showed that the gel beads of immobilized cells are stable with the whole shape and definite fermentation properties.