PRODUCTION OF PROBIOTIC YOGHURT (BIFILACT) BY USING SOME SPECIES OF LACTIC ACID BACTERIA

Abstract

Probiotic lactic acid bacteria was used in manufacturing yoghurt from fortified whole milk. The product was stored under refrigeration for one week. The results showed that yoghurt manufacturing by using single or mixed strain bacteria was acceptable concerning acidity percent as it was 0.52 , 0.92 and 1.20 % using L.acidophilus , B.lactis and mixed culture , respectively for the fresh yoghurt. Total solid percentages of the fresh yoghurt were 16.47 , 16.48 and 15.93% for the three mentioned culture , respectively. Counts of Bifidobacteria in single strain starter and in mixed starter were higher followed by L.acidophilus in mixed starter, while counts were lowest in L.acidophilusin in single strain starter one week after storage counting were 81× 107 , 81× 107 , 36× 107 and 11× 107 c.f.u/ml. respectively, and these counts were within the acceptable ones of WHO and FAO values. Sensory evaluation showed that the product was acceptable for at least one week storage without any microbial or sensory changes which indicated that it can be used as a therapeutic product. Physical properties of the freeze dryed product were also studied and the results showed the ability for reconstruction and using it in capsule formulation.