Growth of fungal contamination in fermented milk containing bifidobacteria and Lactobacillus acidophilus

The isolation, enumeration and identification of yeasts and molds were carried out in fifty samples of commercial fermented milk containing bifidobacteria and Lactobacillus acidophilus. The determinations were made at 2, 10, 17, 24, 28, 31, 36, 42, 51 and 84 days of refrigerated storage (7 C). Fungal contamination was observed in 94% of the samples. The presence of yeasts was verified in all cases whilst the appearance of filamentous molds was occasional. In all the cases where fungal contamination was established, there was a steady presence of Candida krusei, which proved to be the only yeast identified. The filamentous molds detected were identified as Geotrichum candidum. The level of contamination by yeasts underwent a clear progression during the whole storage period and this evolution was related to the acidity level. The contamination is attributable to hygiene deficiencies during packaging