45D-16 |
Use of pediocin of Pediococcus parvulus as an alternative to immobilize antimicrobials in biodegradable films |
B. QUINTERO-SALAZAR1, J. Vernon-Carter2, I. Guerrero-Legarreta2, and E. Ponce-Alquicira2. (1) Biotecnología, Universidad Autónoma Metropolitana, Av. San Rafael Atlixco No.186, Col. Vicentina, Apartado postal 55-535, Mexico D.F., 09340, Mexico, (2) IB-IPH Edible films provide protection against deteriorative processes, they are able to include additives and antimicrobial agents in their structure. A bacteriocin produced by Pediococcus parvulus is heat-stable with a wide inhibitory spectrum, therefore it has potential as preservative for meat and meat products. On the other hand, whey protein isolates (WPI) films produce transparent and flexible edible films with excellent oxygen and aroma barrier properties. However, the process to prepare WPI films requires the use of high temperature, high homogenization rate, and lipids addition for water vapor permeability. The objectives of this work were to study the stability of pediocin under the conditions used for WPI film formation, and to determine the antimicrobial activity of WPI films added with pediocin. Freeze dried pediocin extract was dissolved in phosphates buffer and subjected to heat treatment at 90°C for 1 to 30 minutes, homogenization at 13, 000 rpm for 30, 60, 90, 120, 150, 180 and 240 seconds, and stearic acid addition (0,2,4,8,10 and 15%). Pediocin activity was analyzed by the diffusion method using Listeria innocua as indicator. Finally, WPI films were added with various pediocin concentrations. Bacteriocin activity was analyzed by placing the film on petri dishes inoculated with an indicator strain. Bacteriocin activity was not affected by heating at 90°C, although, the activity was reduce 10% by homogenization for 5 minutes. Stearic acid addition decreased pediocin activity. Conversely, the antimicrobial activity of WPI films progressively increased with pediocin concentration. The stability of pediocin at 90°C and during homogenization suggested that it can be added to WPI as an antimicrobial compound.
Session 45D, Food Packaging: General
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