不同乳酸菌发酵黄浆水对酸浆豆腐凝胶特性及其品质的影响

Effects of different lactic acid bacteria fermented yellow serous water on gel properties and quality of fermented soybean whey tofu

目的研究不同乳酸菌发酵黄浆水对酸浆豆腐凝胶特性及其品质的影响,探究酸浆豆腐的凝固机制,提高酸浆豆腐的品质稳定性,量化生产工艺参数。方法以大豆为原料,分别以鼠李糖乳杆菌、耐高温鼠李糖乳杆菌、混合菌(乳酸链球菌乳亚种、嗜热链球菌和耐高温鼠李糖乳杆菌)发酵黄浆水制成的酸浆作为凝固剂制作豆腐,测定豆腐的凝胶强度、持水性、出品率、色差、质构特性、感官评价、流变特性、水分分布、二级结构、三级结构、表面疏水性和微观结构等指标。结果混合菌酸浆诱导的豆腐质构特性最好,具有较高的凝胶强度、持水性和储能模量,分别为579.63g、69.93%和8166.4Pa,感官评分最高。而耐高温鼠李糖乳杆菌酸浆诱导的豆腐凝胶强度和持水性比鼠李糖乳杆菌酸浆诱导的豆腐高。鼠李糖乳杆菌酸浆诱导的豆腐则硬度较低,为1481.38 gf,水分流动性较大。表面疏水性结果显示,混合菌酸浆诱导的豆腐表面疏水性较低,为268.75%,三级构象最为紧密,鼠李糖乳杆菌酸浆豆腐表面疏水性较大,为469.29%,三级构象较为松散。扫描电镜结果显示,混合菌酸浆豆腐呈致密均匀的三维网状结构,耐高温鼠李糖乳杆菌酸浆豆腐凝胶较为连续,孔隙较大,鼠李糖乳杆菌酸浆豆腐凝胶网络结构较松散。结论混合菌酸浆可使豆腐具有较好的凝胶特性和品质,为酸浆豆腐的品质提高提供了理论和技术支持。

Objective To study the effect of different lactic acid bacteria fermented yellow serous water on the gel characteristics and quality of fermented soybean whey tofu,explore the coagulation mechanism of fermented soybean whey tofu,improve the quality stability of fermented soybean whey tofu,and quantify the production process parameters.Methods Tofu was made from soybeans,and the coagulant was a sour paste made from fermented yellow water by Lactobacillus rhamnosus,Lactobacillus rhamnosus,high temperature resistant Lactobacillus rhamnosus,and a mixture of bacteria(Lactococcus lactis subsp.,Streptococcus thermophilus,and Lactobacillus rhamnosus,high temperature resistant Lactobacillus rhamnosus),and the coagulant was used to make the tofu.The gel strength,water holding capacity,yield,chromatic,textural properties,sensory evaluation,rheological properties,moisture distribution,secondary structure,tertiary structure,surface hydrophobicity and microstructure of tofu were determinated.Results The best textural properties of tofu were induced by the mixed bacterial acid plasma with high gel strength,water holding capacity and energy storage modulus,which were 579.63 gf,69.93%and 8166.4 Pa,respectively,and the highest sensory score.While the gel strength and water holding capacity of tofu induced by high temperature resistant Lactobacillus rhamnosus acidophilus plasma was higher than that of tofu induced by Lactobacillus rhamnosus acidophilus plasma.Lactobacillus rhamnosus plasma-induced tofu,on the other hand,had lower firmness of 1481.38 g and higher water mobility.The surface hydrophobicity results showed that the surface hydrophobicity of tofu induced by mixed bacterial acid slurry was lower,at 268.75%,with the third order conformation being the most compact.Lactobacillus rhamnosus acid slurry tofu had a higher surface hydrophobicity,at 469.29%,with a relatively loose third order conformation.Scanning electron microscopy results showed that the mixed bacterial plasma tofu showed a dense and homogeneous three-dimensional mesh structure,the high temperature resistant Lactobacillus rhamnosus plasma tofu gel was more continuous and had larger pores,and the Lactobacillus rhamnosus plasma tofu gel network structure was loose.Conclusion Mixed bacteria sour milk can make tofu with better gel characteristics and quality,which provides theoretical and technical support for the quality improvement of sour milk tofu.