Survivability of Lactobacillus rhamnosus during the Preparation of Soy Cheese

The aim of this study was to develop a new probiotic soy cheese on the basis of chinese sufu. The soy cheese was made from soymilk fermented with soy cheese bacterial starter cultures (DH1 and GH4) and L. rhamnosus 6013. After ripening, probiotic soy cheese sensory scores (standard SB/T 10170-93) were compared to the control. The changes in pH, bacterial growth and the survivability of the potential probiotic L. rhamnosus 6013 during fermentation and storage at 10 °C were examined. After 6 h of fermentation, L. rhamnosus 6013 was capable of growing in soymilk as high as 10–10 CFU/mL. After being stored for 30 days at 10 °C, slight decrease in pH and the viable counts of the strain was noticed. The viable counts of L. rhamnosus 6013, DH1 and GH4 were 10 , 10 and 10 CFU/g, respectively, after storage for 30 days. The levels of stachyose, raffinose and sucrose in soy cheese were determined by high performance liquid chromatography. The results indicated that L. rhamnosus 6013 could utilize the soybean oligosaccharides as carbon sources. In addition, 2–4 % of NaCl had little effect on the survivability of L. rhamnosus 6013. It indicated that L. rhamnosus 6013 could withstand the technological processing of soy cheese and had no negative effect on the fermentation and the sensory properties of the soy cheese.