A survey about plain and apricot probiotic drinks in shelf life process by different microbiological parameters

Abstract

In recent years, people tend to consume probiotic products because of their health benefits. In accordance with this purpose, lots of different probiotic products, especially dairy products with or without various fruit contents are produced. Therefore, two commercial probiotic dairy drinks which were plain (PPD) and containing apricot (APD) and control group without any probiotic supplement were investigated in this study. For this aim, coliform (Klebsiella pneumonia (KPA12) as a test microorganism), total lactic acid bacteria, bifidobacteria, Lactobacillus acidophilus, mould and yeast were enumerated and pH alterations were observed during to 21- day shelf life of the drinks. Bifidobacterium animalis subsp. lactis, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strain mix were used as probiotics. Then, KPA12 (6.08 log CFU/mL) was totally prevented at 15th, 16th and 19th days on PPD, APD and Control, respectively. In the meanwhile, any mould and yeast growth were not observed. Additionally, number of total lactic acid bacteria, L. acidophilus and bifidobacteria almost protected to their 7 log CFU/mL level. Similarly, any dramatic changes were not seen on pH levels that ranged 4.15-4.25 of the drinks during the storage.