Utilization of whey for lactic acid bacteria starter culture productions and the effect of protective agent on their survivals
1998
Pattariya Chuthamas
Raw milk produced in rural area was taken to The Royal Chitralada Projects compound for pilot study of cheese production. Whey, a by-products from the cheese processing can be possibly utilized for starter culture production. In this study, yogurt-producing bacteria i.e. Streptococcus thermophilus, Lactobacillus bulgaricus and probiotic bacteria L. acidophilus, were used. Results showed that these bacteria produced acid and curd formation in skim milk within 5.5, 6.2 and 9.3 hours respectively. Optimum condition for growth of bacteria in MRS medium were : temperature 35-40 deg C. Initial pH for Str. thermophilus were 5.0-7.5 while pH 6.5-7.0 were suitable for the rest. The concentration of the inoculum used for all cultures were 0.5-3.0 percent. The production of starter culture using whey was conducted in 3 formulas compared with MRS medium and M17 medium. The formula 4 consisting of whey and yeast extract were suitable for growth all lactic acid bacteria studied. After freeze-drying of cultures studied by gelatin technique, varying protective agents, and storing at 5 deg C and - 20 deg C for 1-3 month, studies showed that nutrient gelatin consisting of meso-inositol and skim milk was the most suitable protective agent for the surviving of all the bacterial strains tested. On freeze-drying process, L. acidophilus was used in further study to produce starter culture production in semi-pilot scale. Suitable freeze-drying process required 8 hours of drying and moisture content of starter culture will be 0.06 percent. After storing at 5 deg C for 1 month, the percentage of surviving cell was 66.7. It is possible to conclude that whey, the by-products of cheese production, is able to be used for starter culture production.
Показать больше [+] Меньше [-]Ключевые слова АГРОВОК
Библиографическая информация
Эту запись предоставил Kasetsart University