Effect of Inoculation with Probiotics and Ageing Time on Selected Functional Properties and Oxidation of Proteins in Dry-Cured Pork Loins

Abstract

The effect of inoculation with a probiotic strain Lactobacillus casei ŁOCK 0900 on changes in selected functional properties and protein oxidation of dry-cured pork loins during ageing was studied. The protein carbonyls content tended to increase significantly (p < 0.05) throughout ageing to reach a maximum level which was approximately two-fold the initial level in both samples. No statistically significant differences (p < 0.05) in carbonyl content were found between the control sample and sample inoculated with L. casei. The passage of ageing time was coupled with a statistically significant (p < 0.05) increase in the trichloroacetic acid soluble peptides concentration in examined loins. Inoculation with a probiotic strain did not have an influence on trichloroacetic acid soluble peptides concentration during the shortest ageing period. Results of measurements carried out for the control sample after 21 and 28 days of ageing were significantly lower (p < 0.05) than those obtained for the sample inoculated with L. casei ŁOCK 0900. Free α-amino acids content in both samples increased continuously with increasing ageing time (p < 0.05). Inoculation of loins with a probiotic strain Lactobacillus casei ŁOCK 0900 resulted in significantly higher peptides and free amino acids content. These differences might affect their organoleptic characteristics that need further investigations.

Keywords:

• Probiotics
• Dry-cured meat products
• Functional properties
• Oxidation
• Ageing

ACKNOWLEDGMENTS

The research described was supported by Ministry of Science and Higher Education (Project No. NN 312 275435). The authors sincerely thank Professor Z. Libudzisz, Head of the Institute of Fermentation Technology and Microbiology, Technical University of Łódź, for kindly providing of the strains of Lactobacillus casei ŁOCK 0900.