Penicillium species during the manufacturing and ripening of Armada raw goat's milk cheese: identification, characteristics and in vitro potential toxins production

The species and characteristics of the moulds of the Penicillhm genus were studied throughout the manufacturing and ripening of Armada cheese. Along t he ripening of four batches of cheese, samples of milk, curd, and 1-, 2-, 4 -, 8-, and 16-week-old cheese were studied. Of the 274 isolates obtained fr om the Oxytetracycline Glucose Yeast-Extract Agar medium throughout the man ufacturing and ripening, 28 were considered moulds belonging to the Penicil lium genus and were identified using both morphological and physiological t ests as following: Penicillium roqueforti (10 strains), P. crustosum (6 str ains), P. commune (4 strains), P. aurantiogreiseum (3 strains), P. verrucos um chemotype I (2 strains), and P. chrysogenum (3 strains). The presence of the species of the Penicillium genus was more important in the last stages of ripening. This fact could be related to the marked increase in the cont ent of total free fatty acids, and of shea-chain fatty acids in particular, which is observed after the second month of ripening in this cheese. The m ycotoxin production was investigated by thin-layer chromatography technique s. All the strains were toxigenic in vitro. (C) Inra/Elsevier, Paris.