Spoilage yeasts of decorated soft cheese packed in modified atmosphere

The yeast content in spoiled decorated soft cheese packed in modified atmosphere from two different dairies was examined. Spoilage was recognized as swelling of packets or as visible growth on the surface of the cheese. In total, 18 yeast species were isolated from the cheese. Torulaspora delbrueckii, Candida parapsilosis, Pichia fermentans, Pichia norvegensis, Pichia membranaefaciens were most commonly isolated in spoiled cheese from Dairy A. Yarrowia lipolytica, Debaryomyces hansenii, Pichia guilliermondii, Cryptococcus sp. and Rhodotorula sp. were most common on cheese from Dairy B. Yeast occurrence on cheese from Dairy A was most likely caused by recontamination from production and packing area. Yeast occurrence on cheese from Dairy B was associated with the yeasts found on the material used for decoration. (C) 1998 Academic Press Limited.