Metabolomic approach study about goat cheese “Bouchon de chèvre” type after prolonged ripening

Abstract

Bouchon de chévre cheese is a surface-mold cheese made from goat's milk with a cylindrical shape and which is generally marketed after 45 days of maturation. It is produced by using starter and yeast cultures such as Penicillium camemberti, Geotrichum candidum, and Kluyveromyces lactis. At an international level, metabolomic analyzes of cheeses have been widely used to determine the metabolites produced after cheese elaboration to determine the final conditions of the cheese taking into account its chemical conditions, a situation that has not been seen in cheeses made in our country. That is why the objective of this work was to carry out an analysis of all the metabolites produced in a cheese made in a tropical area of the state of Veracruz, Mexico. Bouchon de chèvre type cheeses were ripened for 90 days under controlled conditions. to evaluate the impact of ripening time over physicochemical and texture parameters. Changes in hardness, cohesiveness, springiness, chewiness, and gumminess were evaluated by texture profile analysis (TPA). Moisture was evaluated with official methods, whereas pH (center and rind) was measured directly. The lactic acid determination was carried out by high-performance liquid chromatography. Proteolysis was measured using reverse-phase high-performance liquid chromatography. While the antioxidant activity was determined using a 2,2-diphenyl-1- picrylhydrazyl solution. Lipolysis was analyzed using gas chromatography. Analysis of variance (ANOVA) showed significant differences between all parameters except center pH. Correlation analysis exposed significant correlations between all texture parameters evaluated and lactic acid concentration. There was no significant correlation between moisture and other parameters. Analyzed cheeses showed peptides fraction in the retention time of 2.05, 18.36, and 50.11 min for acid-soluble fraction and non-protein protein nitrogen, and showed antioxidant activity from the first day of ripening to 73% discoloration in the DPPH solution at 55 ripening days. Obtained results suggested that ripened Mexican goat cheese had a DPPH radical scavenging activity related to peptides present originally in the milk or released by starter culture action during cheese ripening. The cheeses analyzed showed a few variations in lipid components during the entire ripening process. The ANOVA showed a total of 7 statistically significant compounds. PCA and GDA showed that petroselinic and vaccenic acid and the unidentified compound 31 are the ones that explain the behavior of the lipid fraction to a greater extent.