Main content area

Effect of different dry aging temperatures on Listeria innocua as surrogate for Listeria monocytogenes

da Silva, Astrid Caroline Muniz, de Oliveira Pena, Pâmela, Pflanzer, Sérgio Bertelli, da Silva do Nascimento, Maristela
Meat science 2019 v.157 pp. 107884
Listeria innocua, Listeria monocytogenes, Weibull statistics, beef, processing time, temperature, water activity
The objective of this study was to evaluate the effect of different dry aging temperatures on the behavior of Listeria innocua used as a surrogate of L. monocytogenes. The process was performed in boneless loin pieces for up to 42 days at 2 and 8 °C. The behavior of L. innocua was influenced by the temperature, aging time, and the water activity of the beef surface (P < .05). After 42 days, reductions of 2.38 and 3.37 log cfu/g were obtained on the beef surface aged at 2 and 8 °C, respectively. According to data predicted by the Weibull model, the samples aged at 2 °C would achieve a 4-log reduction with twice the time required for the process at 8 °C. After trimming, 66.7% of the samples aged at 2 °C were positive for L. innocua, whereas at 8 °C the rate was 33.3%. Therefore, the results showed that the increase of process time and temperature as well by decrease of the aw reduces L. innocua counts.