Inactivación de Yersinia enterocolitica en jugos de frutas por ácido ascórbico

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

Mendoza

Jornada; XXI Reunión Científica Anual Sociedad de Biología de Cuyo; 2003

Sociedad de Biología de Cuyo

In humans, Yersinia enterocolitica can cause acute enterocolitis, mesenteric linfoadenitis and pseudoappendicitis. The main form of transmission is water and contaminated food. The objective of this work was to study the effect of ascorbic acid against Y. enterocolitica in fruit juices. Samples used: i) orange juice with pulp (pH 3.52), prepared in our laboratory, and ii) commercial single strength apple juice (pH 3.19). The samples (199 mL) were contaminated with Y. enterocolitica W 1024 0:9 p YV (+) to obtain a final concentration 1 x 10e7 CFU/mL. Samples were treated with 3.4% ascorbic acid and incubated at 25°C. Samples without addition of AA were used as control (C). The counts were made at O, 5, 10, 20, 60 and 90 min in Mac Conkey agar (MC). The results were expressed in log CFU/mL and represent the average of 3 different experiments. The addition of ascorbic acid to orange juice resulted in a reduction of Y. enterocolitica of 5.44 log cycles in 90 min; in apple juice this reduction was of 5.48 log cycles in 20 min (in both cases with respect to time O). The results of this study indicate that ascorbic acid reduces Y. enterocolitica in these fruit juices and that this reduction is faster in apple juice.