Selected Lactic Cultures Improve White Cheese Hygienic Quality

Abstract

Burgos cheese is the main white cheese variety manufactured in Spain. Although made from pasteurized milk no lactic cultures are added to the milk, and cheeses are not salted or are brine-salted for only 10–30 min. High moisture level and pH value and low NaCl content enhance growth of pathogenic and undesirable microorganisms. In the present work the influence of lactic culture inoculation on growth and survival of Escherichia coli in Burgos cheese was investigated, in order to improve its hygienic quality. Pasteurized milk was inoculated in all cases with E. coli INIA 846 (100 cfu/ml). Two lactic cultures were used: culture N (Streptococcus lactic INIA 12) and culture B (Str. lactic INIA 12 + Leuconostoc mesenteroides subsp. cre-moris NCDO 543 + Leuc. mesenteroides subsp. dextranicum INIA 141). Large (1.5 kg) and small (0.5 kg) cheeses were manufactured from all vats. Cheeses were stored at 0 C or 4 C during the first 24 h and at 4 C, 8 C or 12 C for seven additional days.