C. Perez-Perez, S. Altamirano-Romo, E. Lima-Lima, B.E. Garcia-Almendarez and C. Regalado
Book of Abstracts, 2004 IFT (Institute of Food Technologists) Annual Meeting and Food Expo, 13-16 July 2004, Las Vegas, Nevada, USA. 321 pages.
2004
บทคัดย่อ
Antimicrobial films based on sodium caseinateThe antagonism of lactic acid bacteria (LAB) and their antimicrobial metabolites such as bacteriocins can be used in food biopreservation to control the growth of bacterialsfoodbornepathogens.A sodium caseinate (SC) based edible film containing an antimicrobial agent in its biopolymeric surface structure was prepared to examine the antimicrobial effect and mechanical properties.The use of biologically-derived bacteriocins as antimicrobial additives in the SC films is desirable because of their potential safety advantages for packaged foods.A study of the antagonistic effect against a pathogenic bacteria was conducted on a bacteriocinogenic LAB isolated from cheese, identified as LactococcuslactisUQ2.The bacteriocinactivity was quantified by the agar diffusion method.The bacteriocinactivity was produced in a fermenter using whey as alternative culture media, at 30 °C.L. monocytogenes was found to be sensitive to the bacteriocin produced by LactococcuslactisUQ2.Sodium caseinatefilms containing 500 AU/mL were prepared, in 90 mm thick layers.Physico-chemical and antimicrobial tests were conducted on the prepared films, to evaluate their effect on food quality preservation.Tensile strength values were weaker and elongation before breakage was less frequent for films with antimicrobial compounds compared to that of films without the antimicrobial compounds.The use of natural antimicrobials in active packaging may minimize contamination on the food surface due to post-processing contamination, leading to extension of the shelf-life, while maintaining the food safety.