The effect of microbial transglutaminase on probiotic fermented milk produced using a mixture of bovine milk and soy drink

Abstract

In this study, the effects of microbial transglutaminase (m-TGs) enzymes on the physicochemical, microbial and sensorial properties of probiotic fermented milk produced using a mixture of bovine milk and soy drink were investigated. Probiotic fermented milk samples were prepared by 3:1 v/v bovine milk, 0.002 w/v soy drink and 0, 0.5, 1, 1.5 U m-TGs per gram of milk protein. The starter culture used was ABT-2 1000 I (a mixture of Lactobacillus acidophilus LA-5, Bifidobacterium animalis subsp. lactis BB-12 and Streptococcus thermophilus). Viscosity and hardness values increased with increased transglutaminase ratio, whereas syneresis values decreased. All samples had an apparently acceptable number of probiotic bacteria over the storage period. While the minimum and maximum percentage ratios of alcohol components and carbonyl components in total volatile aromatic components of fermented milk samples are 24.75-30.70% (v/v) and 65.66-71.96% (v/v) during storage time, the minimum and maximum percentage ratios of organic acids and esters are 0.56-2.54% (v/v) and 0.73-1.57% (v/v).

Effect of storage time on sensory and instrumental properties of skim‐milk yoghurt obtained with microbial transglutaminase

“…However, consistency, firmness, cohesiveness and residual syneresis (S r ) were higher than those observed for the untreated sample (Figure ). Similar findings were achieved by other researchers confirming that MTG addition (2.2 U/g protein) allowed the firmness of the gel to increase with increasingly significant values during the refrigerated storage (Temiz and Carmak, ). However, in other studies where protein content of 3.50% was used, no differences were found between treated and untreated MTG samples in adhesiveness and cohesiveness values (Tsevdou et al ).…”

Impact of Type and Enzymatic/High Pressure Treatment of Milk on the Quality and Bio-Functional Profile of Yoghurt

“…According to the microbiological analyses, all samples exhibited growth below the detection limit (<2 logCFU/g) for yeasts and molds, whereas the total counts of the starter culture (Streptococcus thermophilus and Lactobacillus bulgaricus) remained above the acceptable limit of 7 logCFU/g, during the 42 days of storage, as also reported in previous studies [2,8].…”

“…In this context, the high pressure (HP) processing of milk and the cross-linking of milk proteins via transglutaminase (TGase) are proposed as alternatives to the costly protein fortification or addition of stabilizing agents in milk [2]. These technologies are reported to improve the yoghurt-making properties of milk and consequently the whey separation phenomena, post-acidification, textural and rheological attributes, sensory characteristics, and flavor evolution and release in either set or stirred yoghurt [2][3][4][5][6][7][8]. However, to the best of our knowledge, these technologies have been studied mainly in bovine milk sources, while little or almost no research has been conducted in ovine milk samples [9].…”

İnek Sütü ve Soya İçeceği Karışımından Üretilen Probiyotik Yoğurtların Tekstürel ve Mikroyapısal Özellikleri Üzerine Transglutaminaz İlavesinin Etkisi

“…Soybeans, Asgrow 3935 were obtained from Black Sea Agricultural Research Institute, Samsun, Turkey. Soy drink production was carried out as described in our previous article Temiz and Çakmak [22]. Soybeans were kept in water for 18 hours at 4°C.…”