Evaluación de la eficiencia de recubrimientos antimicrobianos adicionados con bacteriocinas en la conservación de un producto cárnico
The food packaging technology is constantly evolving in response to changes that exist in modern society, these changes focus to consumer tastes, increasing the life of food, food safety and healthy food, the objective of this study was to evaluate the effect of an antimicrobial coating based on whe...
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| Tipo de recurso: | tesis de maestría |
| Estado: | Versión publicada |
| Fecha de publicación: | 2015 |
| País: | México |
| Institución: | Universidad Autónoma Metropolitana |
| Repositorio: | Repositorio Institucional de la UAM Iztapalapa |
| Idioma: | español |
| OAI Identifier: | oai:bindani.izt.uam.mx:6d56zx080 |
| Acceso en línea: | https://doi.org/10.24275/uami.6d56zx080 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/LEM/Industria y comercio de la carne info:eu-repo/classification/LEM/Meat industry and trade info:eu-repo/classification/LEM/Carne -- Conservación info:eu-repo/classification/LEM/Meat -- Preservation info:eu-repo/classification/cti/6 |
| Sumario: | The food packaging technology is constantly evolving in response to changes that exist in modern society, these changes focus to consumer tastes, increasing the life of food, food safety and healthy food, the objective of this study was to evaluate the effect of an antimicrobial coating based on whey protein isolated added with bacteriocins quality frankfurters during storage. In the first stage extraction bacteriocins was performed and it was analyzed for inhibitory activity thereof, in the second stage the combination of bacteriocins "in vitro" with Listeria innocua, Brochothrix thermosphacta and Weissella viridescens assessed also was standardized technique for the preparation of the coating, to thus evaluate its effect with three organisms under study. In the third stage the antimicrobial coating was applied to frankfurters inoculated with 105 CFU/mL of three sensitive microorganisms, it were evaluated physicochemical and microbiologically for 40 days. Inhibitory activity was determined pediocin 133 being 1956 AU/mL which was evaluated with the susceptible organisms, obtaining Listeria innocua showed greater sensitivity that Brochothrix thermosphacta finally the microorganism Weissella viridescens showed more resistance to pediocin. The inhibitory activity of enterocin 29 was 266 AU/mL 86% lower than pediocin, in this case Weissella viridescens showed greater sensitivity to enterocin, when it was at higher activities, while that Listeria innocua and Brochothrix thermosphacta were showed the same inhibition To evaluate the combination of different concentrations of pediocin 133 and enterocin 29 in vitro there was a significant reduction of the development of the three sensitive microorganisms, by analyzing the fractional area (fa), enterocin-pediocin treatment with combinations (E/P) 500-2000 y1000-2000 AU/mL had a synergistic effect with a fa of 0.04 and 0.03 respectivity, while for Brochothrix thermosphacta, no synergistic effect was found by combining the two bacteriocins, only if applied individually, Weissella viridescens was found no synergistic effect, because this microorganism was inhibited all treatments. To evaluate the antimicrobial activity of coating made with an 80:20 of protein isolate whey (WPI) and mixture bacteriocins at pH 6, best results were found higher concentrations, eventually became a selection of the best combinations to implement in the final stage. Was conducted storing frankfurters treated with the antimicrobial coating. The pH determination showed a decline throughout the storage, probably attributable to the presence of BAL. Lipidic oxidation was a maximum at day 5 for control MDA 1.45 mg/ kg product and for 3 treatments with the highest value with individual pediocin MDA 0.87 mg/kg product, the treatment with combination of bacteriocins was a value MDA 0.7 mg/kg product. In the microbiological analysis Listeria innocua reached a one log cycle decrease relative to the control, a synergistic effect coating with the combination of the two bacteriocins except at day 40, where the effect was additive. With Brochothrix thermosphacta in the first 5 days no treatment effect on all combinations, then increased sensitivity of this microorganism was observed during the storage, relative to Listeria innocua, especially in coating with the combination of the two bacteriocins remaining 1.5 log cycle less than the control. With Weissella viridescens, the treatment with two bacteriocins, showed a synergistic effect on 12 and 26 day obtaining values of 1.5 log cycle less than the control, while for the day 40 there was an additive effect of 3 treatments. In the microbiological analysis of the lactic acid bacteria was observed that treatment with both bacteriocins 0.5 log cycles was maintained unless the control during storage except at day 40 where 1.5 log cycles unless the control. To study microbial diversity, first DNA extraction from samples frankfurters treated with the antimicrobial coating and control, on days 1, 19 and 40, after quantify DNA extracted, proceeded to amplify the same, PCR products were performed by denaturing gradient gel electrophoresis (DGGE), after cutting band, purification and subsequent amplification of DNA fragments proceeded to sequencing, the obtained sequences were searched in BLAST from GenBank were used to find the closest known relatives to the partial 16S rDNA sequences, microorganisms with higher identity: Lactobacillus sakei; Carnobacterium maltaromaticum and Lactobacillus curvatus 28 LMA according to the DGGE gel, Lactobacillus sakei is in all treatments throughout the storage, Lactobacillus curvatus is in all treatments at Day 1 and Carnobacterium maltaromaticum was found on day 1 in individual enterocin treatment and on day 40 in the pediocin- enterocin treatment and control. It is concluded that the frankfurters inoculated with Listeria innocua and Brochrothrix thermosphacta, with antimicrobial coating with combination E/P 2000/2000 AU/mL, kept physicochemical and microbiological quality for 26 days, especially ensuring inhibition of Listeria innocua. |
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