Microbial shelf-life of vacuum packed wild boar meat cuts at two different storage temperatures.

Abstract

In order to collect data about the use-by date of meat cuts from wild boar carcasses, 7 carcasses were cut, in 3 different settings (untrained staff; trained staff at small-scale unit; trained staff at approved game-handling-establishment). Meat cuts were vacuum-packed, stored at two different temperatures (2°C and 3.8°C) and examined in defined time intervals (up to 14 days, 3-4 replicates per cut). At days 0, 3, 7, 10 and 14, samples were tested for pH, Total Viable Count (TVC), presumptive pseudomonas, E.coli, enterobacteriaceae and lactic acid bacteria. E.coli values decreased independent from storage temperature over time. Temperature exerted a significant effect on TVC. At 2°C storage temperature an average increase of 1.5 log cfu/g and at 3.8°C an increase of 2 log cfu/g was observed, depending on type of meat cut and experimental series, the differences could exceed 1 log unit by far. This suggested that a difference of merely 1.8°C storage temperature caused significant differences in TVC. Result of pseudomonas and enterobacteriaceae counts were in the same trend, increase was 1 log cfu/g and 1.5 log cfu/g for 2°C and 3.8°C storage temperature, respectively. Lactic acid bacteria counts increased with 2 log cfu/g at 2°C storage temperature and increased with 3 log cfu/g at 3.8°C storage temperature. A difference in microbial numbers between the samples from the three settings was expected, due to presumed differences in processing hygiene during cutting, but no evidence for such factor was found. Meat from approved game handling-establishment had a short use-by date (based on the level of bacterial contamination). In the two other settings the use-by date was slightly higher. Use-by date at 3.8°C was consistently shorter than at 2°C. Findings demonstrate that both initial bacterial numbers as well as storage temperature have a significant impact on shelf-life.