Probiotic yogurt production by hydroalcoholic extract of Gundelia tourneforti and probiotical kefir and evaluate its effect on probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium bifidum) activity

The probiotic products consumption especially yogurt is very prevalent. Gundelia tourneforti is one of plants that have several beneficial effects. In this study the effect of this plant
hydroalcoholic extract and kefir probiotic on bacteria Lactobacillus acidophilus and Bifidobacterium bifidum growth in yogurt were investigated. The probiotics products were
produced by Tamime standard method. Then the products were investigated sensory, pH, acidity and microbial count in incubation and maintenance term. The data were analysis by
descriptive statistical test with SPSS system. The results of this study showed the time has a negative effect on pH and a positive effect on acidity, so that time increased causes pH decreased and acidity increased. The bacterial count was 1010 cfu.ml in incubation term and remained in this count in maintenance period almost.  The investigation of the results revealed, kefir and Gundelia tourneforti hydroalcoholic extract concentration increased have positive significant effects on Lactobacillus acidophilus and Bifidobacterium bifidum. In sensory evaluation turned out yogurt containing 0.6 gr Bifidobacterium bifidum and 0.6 gr Lactobacillus acidophilus gained superlative and lowest score respectively.