Effects of salt percentage (0.5 or 1%), combination (NaCl or NaCl/KCl) and stage of adding salt on biochemical, microbiological and sensory characteristics of probiotic Doogh

The combined effects of salt percentage (0.5 or 1%), its adding order (before or after the fermentation) and different ratios of NaCl/KCl (100/0 and 50/50) were used in the probiotic Doogh. Two probiotic bacteria (Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12), along with the yogurt bacteria were used. pH, acidification and redox potential were measured during the fermentation period. Moreover, viability of probiotic bacteria was determined within 7-day intervals during the storage period. The sensory parameters were also evaluated at days 0 and 21. The partial substitution of NaCl with KCl in the studied concentration had a positive influence on the viability of probiotics. Treatments containing 1% NaCl/KCl and 0.5% NaCl/KCl which were added before fermentation showed the maximum viability of probiotics. The treatments with 0.5% NaCl and then 0.5% NaCl/KCl before fermentation showed higher acceptance. Thus the substitution of 0.5% NaCl with KCl was acceptable. In whole, the treatment containing 0.5% NaCl/KCl before fermentation was the best one for probiotic Doogh with substituted salt.