Factors Affecting the Microbiological Quality of Burgos and Villalón Cheeses at the Retail Level

Abstract

One hundred forty-four samples of Burgos and Villalón cheeses collected during April and July 1983 from retail outlets in Madrid, Spain, were analyzed for microbiological quality. Geometric mean counts were 6.8 × 10⁵ staphylococci/g, 1.0 × 10⁵ coliforms/g and 7.9 × 10³ yeasts/g for Burgos cheese, whereas the respective mean counts for Villalón cheese were 1.4 × 10⁶/g, 8.7 × 10⁴/g and 1.9 × 10⁴/g Coagulase-positive staphylococci represented in April and July, 7.9 and 42.2%, respectively, of the isolates from egg-yolk tellurite glycine agar plates. Fecal coliforms accounted for 5.6 and 26.9% of the isolates from violet red bile agar plates in April and July, respectively. Presence of alkaline phosphatase activity in cheese was not significantly related to numbers of staphylococci or coliforms and should only be regarded as a presumptive test. The use of pH values or total counts as indicators of the microbiological quality of Burgos and Villalón cheeses is also discussed.