Review Book

hybridization probe approach to detect Salmonella in a broad range of foods and environmental samples. The method combines the detection of real-time amplification curves and melt peaks to determine positive or negative results. Presumptive positive results can be obtained in as little as 12–26 h, depending on the matrix, and confirmation can be initiated directly from the primary enrichment by streaking onto ASAP™ and/or CHROMID® Salmonella. Prior to the collaborative study, the GENE-UP ® method was validated according to the AOAC Guidelines (4) in a Performance Tested Method SM (PTM) study. The method was originally validated for liquid whole egg (25 mL), cooked ham (25 g), raw ground beef (25 g), raw chicken breast (25 g), lettuce (25 g), chocolate (25 g), dry pet food (25 g) and stainless-steel environmental surface sponges. It was awarded PTM Certification No. 030803 in March of 2008. Several modification studies were conducted to extend the matrix claims of the assay. In June of 2015, the method was validated for fresh raw ground beef (80% lean, 25 g & 375 g), raw fish (25 g), fresh raw chicken breast (25 g), vanilla ice cream (25 g), dry pet food (25 g) and stainless-steel environmental sponges and awarded PTM Certification No. 061404. In July of 2017, the method was validated for chicken carcass rinse (30 mL), raw ground chicken (25 g), raw beef trim (375 g), raw ground pork (375 g), raw ground bison (375 g), pasteurized liquid egg (100 g), powdered egg (100 g), whey protein powder (375 g), dry pet food (375 g), creamy peanut butter (375 g), dark chocolate (375 g) and garlic powder (375 g). The method was further validated in December 2017 for bulk bagged Romaine lettuce (375 g), and again for dark chocolate (375 g, 42 o C enrichment temperature) in December 2018 and a new certification number, PTM Certification No. 121802, was awarded (5). Two additional matrices, milk chocolate (25 g & 375 g) and dark chocolate (375 g; 36 o C enrichment temperature) were submitted for PTM certification in January of 2020. During the PTM studies, the candidate method was compared to the USDA – Food Safety Inspection Service (FSIS) Microbiology Laboratory Guidebook (MLG) Salmonella Chapter (6)

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