USE OF EXOPOLYSACHARIDE PRODUCING STARTER CULTURES IN THE PRODUCTION OF FUNCTIONAL DAIRY PRODUCTS

Abstract

In this study, seven bacterial cultures were screened for their ability to produce exopolysaccharides. It was found that the bacterial cultures of Lactobacillus delbrueckii subsp. bulgaricus DSM 20080, Streptococcus thermophilus CH-1, Thermophilic culture Yoflex Express 1.0 and Thermophilic culture Yoflex CH-1 were the best. Therefore, these bacterial cultures were selected for further studies as following: 1- Thermophilic culture Yoflex CH-1 as traditional starter (Str.thermophilus+Lb.bulgaricus 1:1) 2- Thermophilic culture Yoflex Express 1.0 as commercial producing- EPS starter. 3- Lactobacillus delbrueckii subsp. bulgaricus DSM 20080 + Streptococcus thermophilus CH-1 (1:1) as laboratory producing- EPS cultures. Part I: Using of Eexopolysaccharides producing LAB starter in making functional low-fat yoghurt. In this part of study, Yoghurt was manufactured from fresh buffaloeś́́ milk standardized to 3% fat for full- fat and 1.5% fat for low- fat treatments, Milk was heated to 85°C for 15 min, immediately cooled to 42ºC and inoculated with 2% starter cultures as following: Standardized buffaloes milk with 3% fat was used as control (CF) and made using (traditional starter culture) while low- fat milk (1.5% fat) was divided into 3 equal portions. The first portion was served as control (Cl) and made with (traditional starter culture), while EPS- producing cultures either commercial (T1) or laboratory (T2) were added for the rest 2 portions, respectively. These mixtures were manufactured as mentioned earlier in Materials and Methods section. The resultant yoghurts were analyzed for the chemical, physiochemical properties, texture profile