Influence of the cultures preparation and the addition of an adjunct culture on the ripening profiles of hard cheese.

CUFFIA, FACUNDO; BERGAMINI CARINA; VERÓNICA WOLF; ERICA HYNES; CRISTINA PEROTTI

Journal of Dairy Research

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2019 p. 120 - 128

0022-0299

The characterization of autochthonous cultures based on their contribution to cheese flavor is an additional selection criterion for their use in cheese making. The objective of the present work was to assess the ability of three strains of mesophilic lactobacilli: L. casei 72 (Lc72), L. paracasei 90 (Lp90) and L. plantarum 91 (Lp91), one strain of thermophilic lactobacilli: L. helveticus 209 (Lh209), and the thermophilic-mesophilic combinations, to grow and produce aroma compounds in a hard cheese model. Microbiological counts, pH and the profiles of carbohydrates, organic acids and volatile compounds were analyzed during incubation for 14 days at 37°C. The population of mesophilic lactobacilli reached levels around 8.0 log CFU mL-1 at 3 days, but then decreased until ~7.0 log CFU mL-1 towards 14 days. Thermophilic lactobacilli population reached and maintained levels around 7.7 log CFU mL-1 during incubation. Carbohydrates were absent in the extracts, and so no change in the pH values and in the levels of lactic acid were detected. Mesophilic lactobacilli, inoculated individually or in association with Lh209, metabolized the citric acid and produced ethanoic acid. The profiles of volatile compounds of mesophilic lactobacilli (characterized mainly by butan-2-one, 3-hydroxybutan-2-one, 3-methylbutan-1-ol, hexan-1-ol, 2-phenylethanol and ethanoic acid) were different from the profile of thermophilic lactobacilli Lh209 (characterized mainly by heptan-2-one, ethyl acetate, isoamyl hexanoate, pentan-1-ol, decanoic acid and 2- and 3-methylbutanal). Cooperative effects in the production of compounds related to cheese flavor, such as 3-hydroxybutan-2-one, ethyl butanoate, ethanol, pentan-2-ol, hexan-1-ol, benzeneacetaldehyde, 2-phenylethanol and heptanoic acid, were largely evidenced between Lh209 and Lp91; in a lesser extent, cooperative effects were also found for Lh209 + Lp90 for the following compounds: 3-hydroxybutan-2-one, isoamyl acetate, and ethanoic acid. Of the mesophilic lactobacilli strains evaluated, Lp91 and Lp90 would be interesting candidates for its use as adjunct cultures in hard cheeses to improve and diversify the flavor.