[Changes in microbiological quality of kefir and yoghurt on the Warsaw market in the years 1995-2001].
The microbiological quality of kefir (61 samples) and yoghurt (92 samples) purchased in retail network in Warsaw in the years 1995 and 2001 has been examined. The total number of bacteria in at least 90% of yoghurt and 73% of kefir was in the range 10(7)-10(9) c.f.u. in 1g. The dominating group of bacteria in kefir were mesophilic lactic acid streptococci and in yoghurt (analysed in the year 2001)--S. thermophilus. The number of L. delbrueckii subsp. bulgaricus in 40% of samples was < 10(7)-in 1 g. The increment of microbiological quality of the examined fermented milks has been observed. More than 86% of kefir and 97% of yoghurt analysed in 2001 were free from coliform bacteria, most of them free from B. cereus, moulds and yoghurt--also from yeasts. About 48% of kefir samples didn't fulfilled the requirements of FAO/WHO requirements concerning the number of yeasts.
Molska
Irena
I
Katedra Technologii i Oceny Zywności Szkoły Głównej Gospodarstwa, Wiejskiego w Warszawie, Zakład Technologii Mleka, 02-787 Warszawa, ul. Nowoursynowska 159 c.
Nowosielska
Renata
R
Frelik
Ilona
I
D000818:Animals; D015169:Colony Count, Microbial; D005285:Fermentation; D005516:Food Microbiology; D006801:Humans; D019344:Lactic Acid / Q000032:analysis; D007778:Lactobacillus / Q000302:isolation & purification; D008892:Milk / Q000382:microbiology; D011044:Poland; D013289:Streptococcaceae / Q000302:isolation & purification; D015014:Yogurt / Q000382:microbiology*
D019344:Lactic Acid