SOME TECHNOLOGICAL PROPERTIES OF PENICILLIUM-ROQUEFORTI STRAINS ISOLATED FROM A HOME-MADE BLUE CHEESE

Nine strains of Penicillium roqueforti isolated from a traditional Spa nish blue cheese (Valdeon cheese) along with two commercial strains we re investigated for their ability to grow at different concentrations of salt and at different temperatures as well as for their proteolytic and lipolytic activities. Low concentrations of salt (1-3%) were stim ulating for all the strains, with 1% salt being the concentration with the highest stimulating effect in nearly all. The rate of growth at 1 0 degrees C was 2-3 times lower than at 25 degrees C, the optimum temp erature for the species. None of the strains, including the commercial cultures, showed proteolytic activity on casein agar, while all of th em were lipolytic on tributyrin agar.