植物乳杆菌接种量对低盐风干肠品质特性及风味特征的影响

Effect of Different Inoculum Levels of Lactobacillus plantarum on Quality Characteristics and Flavor Profile of Low-Sodium Dry Sausage

探究不同接种量10^(5)、10^(6)、10^(7) CFU/g(LP5、LP6、LP7)的植物乳杆菌对低盐风干肠品质特性及风味特征的影响。以低盐风干肠(食盐质量分数为1.75%)为对照组,在发酵第0、3、6、9天对4组风干肠的pH值、水分含量、水分活度、剪切力、乳酸菌数和肠杆菌数进行测定;采用电子鼻与气相色谱-质谱技术,对第9天样品的风味特征进行分析。结果表明,随着发酵的进行,各处理组的水分含量和水分活度逐渐降低,剪切力逐渐上升;发酵结束时(第9天),所有处理组中LP6和LP7的水分含量和水分活度较高,LP7的肠杆菌数最低,各处理组的剪切力无显著差异(P>0.05)。随着植物乳杆菌接种量的增加,低盐风干肠的pH值逐渐下降(除发酵第0天),乳酸菌数逐渐上升(除发酵第6天)。接种植物乳杆菌增加了酸和酯类物质整体含量,不同接种量低盐风干肠挥发性风味差异明显。结合感官评价结果确定接种量10^(6) CFU/g的低盐风干肠的总体可接受性最佳,咸味酸味适中。

The effect of different inoculum levels of Lactobacillus plantarum(10^(5),10^(6) and 10^(7) CFU/g)on the quality characteristics and flavor profile of low-sodium dry sausage were explored in this study.The uninoculated sausage with 1.75%NaCl was regarded as a control.The pH,moisture content,water activity,shear force,lactic acid bacteria(LAB)count and Enterobacteria count of the four samples were measured on days 0,3,6 and 9 of fermentation and the flavor profiles were analyzed on the 9th day by electronic nose(EN)and gas chromatography-mass spectrometry(GC-MS).The results showed that the moisture content and water activity of all treatments decreased gradually as the fermentation progressed;at the end of fermentation(day 9),the moisture contents and water activity of the LP6 and LP7 treatments were higher than those of the other treatments and the Enterobacteriaceae count of the LP7 treatment was the lowest among all treatments,while there was no significant difference in shear force among all treatments(P>0.05).The pH of all treatments decreased gradually(except for day 0 of fermentation)with an increase in the inoculum level,and the LAB count increased gradually(except for day 6 of fermentation).Inoculation with L.plantarum increased the contents of acids and esters.The volatile compound contents of low-sodium dry sausages with different inoculum levels of L.plantarum were significantly different.Finally,sensory evaluation indicated that the overall acceptability of low-sodium dry sausage with an inoculum level of 10^(6) CFU/g was the highest,and its saltiness and sourness were moderate.