EFFECTS OF ORGANIC ACIDS, NISIN, LYZOZYME AND EDTA ON THE SURVIVAL OF YERSINIA ENTEROCOLITICA POPULATION IN INOCULATED ORANGE BEVERAGES

LUCERO ESTRADA CECILIA STELLA MARYS; VELÁZQUEZ LIDIA DEL CARMEN; STEFANINI DE GUZMÁN ANA MARÍA

JOURNAL OF FOOD SAFETY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2010 vol. 30 p. 24 - 39

0149-6085

Inactivation of a Yersinia enterocolitica strain by 3.4% ascorbic, 0.5% citric and 0.2% lactic acids, 100 IU/ml nisin, 2,400 IU/ml lysozyme and 20 mM EDTA, alone and combined, was studied at different temperatures (4 and 25 ºC) in commercial and laboratory-prepared orange beverages.  In laboratory-prepared juice, highest reductions (between 3.06 and 4.07 log units) were obtained with acids mixtures at 25 ºC after 20 min of incubation. At 24 h of incubation EDTA was bactericidal and the mixtures with nisin or lysozyme resulted in count reductions of 6.03 and 5.98 log units, respectively. In commercial orange beverage, ascorbic and citric acids gave reductions of 5.43 and 4.26 log units, respectively. The three acid mixtures were bactericidal within the first 10 min. EDTA alone or mixed completely inhibited Y. enterocolitica strain at 6 and 24 h of incubation. At 4 ºC all the results were significantly lower than at 25 ºC.