Lactobacillus bulgaricus content in home made Bulgarian yogurt

                            Dimov N., ¹  Damianov C.¹, Koleva M.¹, Doycheva A.¹, Satchanska G.¹         

^1- New Bulgarian University, Department Natural Sciences ,

 1618 Sofia, 21 Montevideo str., Bulgaria

gsatchanksa@nbu.bg

 

Lactobacillus delbruekii, subsp. bulgaricus display broad biological activity  due to its probiotic properties. The aim of our investigation was to count Lactobacillus bulgaricus CFU in bulgarian home made yogurt. Tree samples of home made sheep and cow yogurt were analyzed. Two samples (S7 and S8) originated from area of Velingrad, Rodopa mountains and one sample (S9) was supplied  from Montana, a valley region in Northwestern Bulgaria. S7 and S9 yogurt were produced from cow milk while S8 was prepared from a sheep milk. The fermentations were performed with home cultivated unidentified bacterial cultures. Analyzes were conducted on solid MRS media by Koch’s method. The experimental data revealed that sheep yogurt possess the highest count of Lactobacillus bulgaricus – 4.4 x 10⁷ CFU per g. Both cow yogurt samples showed less amount of lactobacteria compared to sheep yogurt - 3.3 x 10⁷ per g in sample S7 and 0.7 x 10⁷  CFU per g in sample S9. Obtained results demonstrated that number of lactobacilli in mountain  orginating yogurts exceed significantly the standart count demanded by the  Bulgarian State Standard BDS 12:2010 “Bulgarian yogurt”. We found that sample S9 match BDS 12:2010. Our results proved the excellent biological properties of home made Bulgarian yogurt.

Key words: home made yogurt, Lactobacillus bulgaricus, sheep milk, cow milk