Effect of beef treatment with lactic acid and lactic acid bacteria on myofibrillar protein degradation and dynamic rheology

SIGNORINI, M.L.; PONCE-ALQUICIRA, E.; GUERRERO-LEGARRETA, I.; SALAZAR, J.A.

JOURNAL OF TEXTURE STUDIES

Blackwell Publishing

Año: 2007 vol. 38 p. 373 - 392

0022-4901

Lactic acid has been used as an efficient decontaminant in meats aimed for direct consumption or product fabrication. However, reports on the functionality of proteins extracted from lactic acid-treated meat are scattered. The objective of this work was to study the degradation and gelling ability of myofibrillar protein extracts obtained from beef treated with lactic acid of chemical and microbial origins, stored at 4 and 20C. The gelling ability was considerably reduced by lactic acid treatment as a result of protein denaturation in acid conditions at both storage temperatures. Scanning electron microscopy showed loose structures resulting in low penetration resistance and storage modulus. Treatments with lactic acid or lactic acid bacteria (LAB) had similar effect on tan d, affecting gel rigidity but not elasticity. Penetration in gels obtained from LAB-treated meat was highly correlated with myosin degradation. Lactobacillus carnis-treated meat produced compact gels with high penetration resistance and storage modulus, although the structure became looser with storage time. LAB treatment, although not as efficient as lactic acid as a meat preservative, is a milder process causing less severe changes in meat structure rheology.