Characteristics of “Tetilla” pasteurized milk cheese manufactured with the addition of autochthonous cultures

Abstract

Fourteen batches of Tetilla, a short-ripening cows-milk cheese produced in Galicia (NW Spain), were prepared from pasteurized milk inoculated with autochthonous cultures isolated from Tetilla raw milk cheeses. Two batches were made with an acid-aromatic starter containing Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. lactis var. diacetylactis strains. Twelve batches were made with the same lactococcal starter plus one of lactobacilli, leuconostoc, enterococci or micrococci strains. The microbiological, chemical, biochemical and sensory characteristics of the different batches were studied. Cheese batches made with micrococci strains showed greatest diversity, while cheese batches made with lactococci strains were the most homogeneous. Mean counts of aerobic mesophilic bacteria, lactic acid bacteria and citrate-fermented bacteria were similar in all cheese batches. Coliforms were only detected in five batches and Escherichia coli, Staphylococcus aureus, Listeria monocytogenes and Salmonella spp. were not detected. pH, total solids and fat contents agreed with the specifications of the Appellation of Origin of Tetilla cheese. Ash and protein contents were lower than those observed in Tetilla raw milk cheese. The mean degradation of β-casein in the cheese batches made with starter including lactobacilli was lower than in the remainder, while the degradation of α s1-casein was higher. These cheese batches and those manufactured with the addition of Leuconostoc showed the highest diacetyl-acetoin content. The most desirable sensorial characteristics were achieved in the batches elaborated with acid-aromatic starter with the addition of selected enterococci or micrococci strains.