Yeasts and filamentous fungi associated with some dairy products in Egypt.

This work aimed to identify and evaluate the diversity of yeasts and filamentous fungi that contaminate some dairy products (fresh buffalo milk, plain yoghurt, butter and Kareisk cheese) in Assiut city, Egypt. The identification was based on phenotypic characteristics, and genotypically in case of yeasts. The pHs of all dairy products lie within the acidic range, but yoghurt registered the highest value. A total of 41 genera and 89 species+3 varieties were recovered from all dairy products investigated on DRBC (26 genera representing 59 species+1 variety), DG18 (32 genera, 56 species+2 varieties) and MY50G (31 genera, 64 species+2 varieties). From these, filamentous fungi were represented by 21 genera and 59 species+2 varieties, and yeasts by 20 genera and 30 species+1 variety. In all products except yoghurt, the xerophilic media (DG18 and MY50G) supported more diversity of fungal species than the general medium (DRBC). Reversely, DRBC supported more propagules originated from all products than DG18 and DRBC. On the other hand, the highest numbers of propagules were recovered from Kareish cheese and butter on MY50G, while the lowest numbers were recorded from yoghurt and raw milk on MY50G. Moreover, yeasts constituted the greatest part of propagules from the four products on the three isolation media except the raw milk on MY50G. From yeasts, Candida, Cyberlindnera, Debaryomyces, Galactomyces, Kazachstania, Kluyveromyces, Myerozyma, Pichia, Rhodotorula, Trichosporon; and from filamentous fungi, only Aspergillus, Cladosporium, Mucor and Penicillium were found contaminating all dairy products. Possible medical problems related to the presence of these fungi or to their metabolic products are discussed.

Moubasher AH ，Abdel-Sater MA ，Soliman ZSM 《-》

Diversity of yeasts and moulds in dairy products from Umbria, central Italy.

Cenci-Goga B ，Cruciani D ，Crotti S ，Karama M ，Yıldırım G ，Bulut M ，Marino C ，Grispoldi L ... -  《-》

[Contamination of dairy products by yeasts-like fungi].

Białasiewicz D ，Kłosiński M 《-》

The diversity of eukaryotic microbiota in the traditional Slovak sheep cheese--bryndza.

We investigated the occurrence and diversity of yeasts and filamentous fungi in bryndza an artisanal Slovak soft spreadable cheese prepared from raw sheep milk or from a mixture of sheep and cow milk. Samples collected during four months of the summer production period from two locations (northern and southern parts of central Slovakia) contained 10(5)-10(7) (cfu) yeasts and about 10(2) (cfu) of mold per gram of wet weight. Further characterization by conventional taxonomy and sequence comparison of D1/D2 region from 26S rRNA gene revealed Mucor circinelloides v. Tieghem as the predominant filamentous fungus. A novel Geotrichum sp. together with Kluyveromyces (K. lactis/K. marxianus) was identified as the most abundant yeast species. Occasionally other yeasts, such as Candida inconspicua, Candida silvae, Pichia fermentans and Trichosporon domesticum were found. Conventional taxonomy readily identified isolates to the genus level, but DNA sequence comparison was capable of discriminating them at the species level.

Laurencík M ，Sulo P ，Sláviková E ，Piecková E ，Seman M ，Ebringer L ... -  《INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY》

Identification of fungi from dairy products by means of 18S rRNA analysis.

Cappa F ，Cocconcelli PS 《INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY》