EN
The purpose of the work was to determine the quantitative and qualitative contamination of a yolk powder according to Polish regulations. The studies were carried out on 610 samples of different batches. There was estimated: the total number of aerobic bacteria in 1 g of a sample, the presence of Salmonella and Shigella strains, mould and yeast, and titers of E. coli, coagulase-positive staphylococci, enterococci, Proteus spp and anaerobic spo- rogenic bacilli. It was found that: a mean contamination with aerobic bacteria was 8.5 X 10° per 1 g, (from 0 to 2.8 X 105), 61.64% of the samples showed the rate infection from 0 to 10s bacterial cells per 1 g, and 24.59 per cent possessed the content from 10³ to 104/lg, 11.15% with 10⁴—10s and 2.62% with 103—3 X 103. There was not found the presence of Salmonella or Shigella strains. E. coli was noted in 13.93% samples (titer: 0.1—0.001), coagulase positive staphylococci in 4.1% (titer: 0.1—0.01), enterococci in 10.49% (titer: 0.1—0.0001), and Proteus spp in 9.02% (titer: 0.1—0.0001). Anaerobic sporogenic bacilli were abserved in 2.62% samples (titer: 0.1—0.01). The contamination with moulds and yeasts was found in 81 samples i.e. in 13.28%. A mean contamination of a sample was 1.1 X 10².