The aim of this work is to research various pasteurization regimes and albuminous milk products influence on the quality of kefir. The research was made in the Food Institute of Kaunas Technology University, 8 aliquots of kefir were made and evaluated in laboratory conditions. These raw milk pasteurization regimes were applied- instantaneous pasteurization (in 87-90°C temperature), pasteurization maintaining to 30 min. (in 87-90°C temperature), pasteurization maintaining to 60 min. (in 87-90°C temperature). The raw milk of these aliquots was enriched with 1%, 2%, 3% fat-free milk powder and with 1%, 2%, 3% whey powder ripening the mixture to 60 min. in 87- 90°C pasteurization temperature. Physical and chemical, microbiological indicators and sensual qualities were determinated by standard methods. It is determinated that the long-lasting milk pasteurization (maintaining to 30-60 min. in 87- 90° C pasteurization temperature), compared with the instantaneous pasteurization, increases viscosity of the product and enriches sensual qualities. Enriching of milk with whey powder in production of kefir stimulates the activity of milk acid bacteria. In comparison, aliquots enriched with 1%, 2%, 3% whey powder, it is determinated that the best is aliquot of kefir among which production it is interspersed 3% whey powder; physical-chemical and sensual qualities of the product signally better then. In comparison all the data of the experiment, the kefir characterized with the best... [to full text]

The aim of this work is to research milk and kefir microbiological indicators according to microbiological risk factors in the milk processing company A. Work tasks: to analyze drinking milk, ultra high temperature pasteurized milk and kefir descriptions and factors of the risk in technological process schemes; microbiological factors of the risk control schemes; samples of these products microbiological indicators according to company’s self-control plan. Conclusion: The main microbiological risk factors in drinking milk is total bacterial count, coliform bacteria, Salmonella; in the kefir – coliform bacteria, yeasts and moulds. Principals control points in drinking milk, ultra high temperature pasteurized milk and kefir technological schemes are: reception of the raw cow’s milk; freezing of the raw cow’s milk, storage and keeping; pasteurization of milk and freezing, pasteurized milk compound storage and keeping; milk warming, deaeration, homogenization, sterilization and refreshing (only for ultra high temperature pasteurized milk); repeated thermal treatment, cooling up to inoculation temperature (only for kefir); inoculation and incubation (only for kefir); storage. In the company’s A self-control plan preview principal control points microbiological risk factors are controlled by keeping a check of heating and freezing stages temperature and duration, monitoring of microbiological parameters are made not less than 4 times per year. Coliform bacteria and total bacteria... [to full text]