ماندگاري بيفيدوباكتريوم لاكتيس و لاكتوباسيلوس اسيدوفيلوس در دوغ حاوي عصاره كاكوتي

Survival of Bifidobacterium lactis and Lactobacillus acidophilus in Iranian doogh flavored by ziziphora extract

In the present work, survival of two most important commercial strains of probiotic bacteria, i.e., Lactobacillus acidophilus (La5) and Bifidobacterium lactis (Bbl2), during production and cold storage of Iranian Doogh, containing Ziziphora extract was studied. The bacteria inoculated into three types of Doohg, a plain sample as the control one, and two samples containing 1% and 2% Ziziphora extract. Survival of probiotic bacteria, pH, acidity and organoleptic characteristics of bio- Doogh were examined during a nine-week cold storage time (4°C). Our results revealed that the population of viable B. lactis reduced by 2.5 log cfu/ml, while L. acidophilus count reduced to zero after eight weeks at 4°C. The pH and acidity of bio-Doogh were not changed significantly (p>0.05) during cold storage period. Also, the organoleptic characteristics of the studied samples changed significantly (/?<0.05). Bio-Doogh with Ziziphora extract had higher flavor scores than bio-Doogh without Ziziphora extract.