P2-124 Domestic Consumer-style Storage and Thawing Practices: Effect on Salmonella in Poultry-based Meat Preparations

Monday, July 27, 2015
Exhibit Hall (Oregon Convention Center)
Anna Roccato , Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe) , Padova , Italy
Mieke Uyttendaele , Ghent University , Ghent , Belgium
Veronica Cibin , Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe) , Padova , Italy
Federica Barrucci , Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe) , Padova , Italy
Veronica Cappa
Paola Zavagnin
Alessandra Longo
Antonia Ricci , Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe) , Padova , Italy
Introduction: Time-temperature abuse has been reported as one of the most common contributory factors in salmonellosis strong-evidence outbreaks. Studies on the temperature of domestic refrigerators showed that from 55 to 80% of refrigerators operate at a temperature > 5°C; moreover 46 to 60% of consumers preferred to thaw food on the kitchen countertop instead of the refrigerator.

Purpose: The purpose of the study was to record the effect of different domestic refrigeration temperatures and thawing methods on the presence and numbers of Salmonella spp. in poultry-based meat preparations.

Methods: Burgers, sausages and ready-to-cook kebabs were submitted to: i) storage at three refrigerator temperatures (4°C, 8 or 12°C), with or without prior temperature abuse (25°C for 2 hours simulating shop to home transport) and ii) thawing according to two methods (overnight in refrigerator at 8°C versus on the kitchen countertop at 23°C). Storage tests were carried out on naturally or artificially (Salmonella Typhimurium at ca. 10 CFU/g) contaminated products while freezing/thawing tests were conducted only on artificially contaminated products (Salmonella Typhimurium at ca. 10, 100 and 1000 CFU/g).

Results: Artificially contaminated products showed substantial growth of Salmonella Typhimurium at 12°C (from ca. 8 MPN/g to > 710 MPN/g) in kebabs after 7 and 10 days but more moderate growth in sausages (from ca. 14 MPN/g to a maximum of 96 MPN/g after 9 days). Storage of naturally contaminated burgers or sausages (contamination ≤ 1 MPN/g) and short temperature abuse (2 h at 25°C) did not facilitate an increase in Salmonella presence and numbers. Thawing overnight in the refrigerator led to either a moderate reduction or no change Salmonella Typhimurium numbers in meats.

Significance: Time-temperature abuse can cause a substantial increase of Salmonella numbers in some types of meats, thus efforts for dissemination of consumer guidelines on correct storage and handling of food need to be continued.