V. Fadaei, F. Mohamadi-Alasti and K. Khosravi-Darani
Functional foods are among the topical issues in nutrition, nutritional foods, medicine and health fields. Considering the unique properties of Spirulina platensis, it can be used to enrich yogurt. The main purpose of this research was to monitor the influence of the powdered Cyanobacterium Spirulina platensis added to the yoghurt containing Lactobacillus acidophilus and spinach on the survival of yogurt starter culture during the refrigerated storage. The cell viability of yoghurt starter cultures (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus) and Lactobacillus acidophilus under refrigeration conditions in yoghurts prepared with (0.3, 0.5 and 0.8 (w/w) %) the addition of Spirulina powder and with (10 and 13 (w/w) %) spinach was investigated. The yoghurts were prepared under hygienic laboratory conditions. The samples of yoghurts were stored at 4 °C and investigated on days 1, 7, 14 and 21. Viable counts of the lactic acid bacteria were above 6 log cfumL-1 of all “Spirulina powder” added at the end of the storage period. The results showed the positive effect of S. platensis powder on the survival of the lactic acid bacteria during the storage of probiotic yoghurt containing spinach (P≤0.01). It was determined that Spirulina powder added to yoghurt is a good medium for lactic acid bacteria during the 21 days of the refrigerated storage. According to final results, the probiotic yoghurt sample containing 0.5 % (w/w) Spirulina platensis and 10 %(w/w) spinach was selected as the preference treatment.