THE ACIDOGENIC METABOLISM OF LACTOBACILLUS PLANTARUM CRL 681 IMPROVES SARCOPLASMIC PROTEIN HYDROLYSIS DURING MEAT FERMENTATION

The hydrolysis of sarcoplasmic proteins during the growth of Lactobacillus plantarum CRL 681 isolated from fermented sausage was evaluated. Fermentation was carried out in a meat model system under controlled pH conditions (pH 4.0 and 6.0) at 30C for 96 h. The ability of this strain to grow and degrade soluble meat proteins at both assayed pHs was demonstrated. Results showed that sarcoplasmic protein hydrolysis at pH 4.0, as occurring during sausage fermentation, can be attributed to the combined action of acidic meat endogenous proteases, L. plantarum CRL 681 proteolytic activity and acid-induced changes arising from the bacterial fermentative metabolism. On the other hand, bacterial proteolysis was mainly involved on the hydrolytic changes observed at pH 6.0. PRACTICAL APPLICATIONS Lactobacillus plantarum CRL 681 isolated from Argentinean sausages showed to display technological metabolic traits such as high acidification rate, proteolytic and peptidase activity, biogenic amines degradation and absence of amino acid decarboxylase activity which can beneficially affect the quality and safety of fermented sausages. In addition, from the results of this study, L. plantarum CRL 681 acidogenic metabolism not only would assure hygienic quality of fermented sausages but would increase free amino acids and peptides release from meat proteins. As a whole, this strain has the potential to be successfully used as starter culture to improve final product quality.