The group of psychrotrophic microorganisms belongs to the microorganisms representing a risk for human health as well as a risk of milk and milk products spoilage. Some genus are considered to be significant producers of proteolytic and lipolytic enzymes. In this work, we analysed raw milk samples (n = 109) originated from 26 different suppliers from the area of North and Middle Moravia. The screening was performed from March 2007 to February 2008. The total bacterial counts (TBC) ranged between 3.2 × 103 to 8.3 × 106 CFU/ml. The psychrotrophic bacterial counts (PBC) ranged between 1.0 × 103 to 8.2 × 106 CFU/ml. Total of 48.62 % and 48.62 % of samples exceeded the hygienic limit in raw milk for TBC and PBC, respectively. The correlation between TBC and PBC was highly significant (r = 0.87).Significantly higher (P < 0.05) numbers of psychrotrophic microorganisms were detected in summer months. The identification of isolates was carried out and all strains were sreened for ability to produce proteolytic and lipolytic enzymes. The most commonly identified genus in raw milk was of the genus Pseudomonas. The ability to produce proteases or lipases was found at 76 % identified bacterial strains.

BURDYCHOVÁ, R, HOFERKOVÁ, P.: Monitoring of probiotic bacterial cells Lactobacillus casei in dry fermented sausages. Acta univ. agric. et silvic. Mendel. Brun., 2008, LVI, No. 2, pp. 39-44 Combination of microbiology cultivation methods and methods of molecular biology is the best way how to achieve correct qualitative and quantitative probiotic analysis. The aim of this study was mo nito ring of amounts of diff erent starter bacteria supplemented with probiotic bacterial cells Lactobacillus casei (Chr. Hansen) during fermentation and ripening of fermented sausages. Two starter cultures, one consisted of Pediococcus pentosaceus and Staphylococcus xylosus, the second of Pediococcus pentosaceus and Staphylococcus carnosus, were used for the production of sausages. As a detection method of starter and probiotic cell counts, the cultivation on MRS -IM -sorbitol agar was used. Furthermore, the confi rmation of L. casei was carried out using species specifi c PCR. The counts of probiotic L. casei in both probiotic sausages were 10 6 /g and stayed at this level during the whole ripening period (100 days). The counts of starter bacteria were 10 7 /g a er the 7 days of fermentation and stayed at this level during the whole fermentation period. PCR from one bacterial colony confi rmed the identity of L. casei in 80% of analysed colonies. fermented sausages, starter cultures, probiotic, Lactobacillus casei, MRS -IM -sorbitol agar Surovinou pro výrobu fermentovaných salámů je hovězí maso, vepřové maso a tuk. Chlazené nebo zmrazené suroviny se míchají s kořením, cukry, askorbáty, směsi soli a dusičnanu a startovacími kulturami a kutrují se na požadovanou zrnitost (BUC-KENHÜSKES, 1993). Dílo se naráží do střev, zaudí studeným či horkým kouřem a zraje ve zracích komorách při požadované teplotě a vlhkosti vzduchu.Startovací kultury jsou většinou směsí bakterií mléčného kvašení (Lactobacillus, Pediococcus), kataláza pozitivních koků (Staphylococcus, Micrococcus