Survey on mycoflora of cow and buffalo dairy products from Southern Italy

Economic losses of dairy products due to spoilage by yeasts have been incre asing in European companies because of the reduced use of preservatives, pa ckaging in modified atmospheres, or new formulations that do not strictly c ontrol the growth of these organisms. This study reports the results of a s urvey of yeast species and populations in 145 samples of cow and buffalo da iry products collected in some regions of Southern Italy. Yeasts were isola ted from 74% and 57% of cow and buffalo products, respectively. Candida inc onspicua was the predominant species in unripened products from cow's milk, while C famata was detected in medium and long-term ripened dairy products , mostly in association with other yeasts and with moulds belonging to the genus Penicillium. For dairy products produced from buffalo milk, C inconsp icua was the most important yeast frequently isolated from dairy products. Total yeast populations ranged from 5 X 10(2) to 5 X 10(5) cfu/g, indicatin g a good hygienic quality of the products. The isolation of C albicans from one stracciatella sample is noteworthy, as this yeast represents a potenti al contamination by human. Even though yeasts are considered as environment al contaminants, the occurrence of some of them in dairy products at high l evels could represent a risk for human health, in particular for immunocomp romised patients. (C) 2001 Elsevier Science B.V.. All rights reserved.