P2-11 Effects of Antimicrobial Treatments, Surface Browning Method and Product Dimensions on Salmonella Contamination in Not-Ready-to-Eat, Surface-browned, Frozen, Breaded Chicken Products

Tuesday, July 24, 2012
Exhibit Hall (Rhode Island Convention Center)
Galatios Moschonas, Colorado State University, Fort Collins, CO
Ifigenia Geornaras, Colorado State University, Fort Collins, CO
Jarret Stopforth, PURAC America, Inc., Lincolnshire, IL
Dale Woerner, Colorado State University, Fort Collins, CO
Keith Belk, Colorado State University, Fort Collins, CO
Gary Smith, Colorado State University, Fort Collins, CO
John Sofos, Colorado State University, Fort Collins, CO
Introduction: Not-ready-to-eat (NRTE), surface-browned chicken nuggets, strips and stuffed entrees have been associated with salmonellosis outbreaks due to inadequate or no cooking of the products before consumption.

Purpose: This study evaluated the effects of antimicrobial treatments, surface browning method and product dimensions on inoculated Salmonella in a NRTE, surface-browned, frozen, breaded chicken product.

Methods: Fresh chicken breast meat portions (5×5×5 cm) were inoculated (5 log CFU/g) with Salmonella (7-strain mixture) and mixed with solutions of caprylic acid (CAA; 0.0625%)+carvacrol (CAR; 0.075%), CAA (0.25%)+ε-polylysine (POL; 0.5%), CAR (0.15%)+POL (0.5%), CAA (0.0625%)+CAR (0.075%)+POL (0.5%), or distilled water (control). Sodium chloride (1.2%) and sodium tripolyphosphate (0.3%) were added to all treatments (5% total moisture enhancement), and then ground and formed into 9×5×3 cm, 150 g portions or 9×2.5×2 cm, 50 g portions. Samples were coated with breadcrumbs, surface-browned in an oven (208 °C, 15 min) or by deep-frying in vegetable oil (190 °C, 15 s), packaged, and stored (-20 °C, 8 days). Pathogen counts of products (two repetitions, three samples each) were statistically analyzed and independent variables included antimicrobial treatment, browning method, product dimensions, and their interactions.

Results: Total reductions of inoculated (4.9 log CFU/g) Salmonella in control oven-browned products were 0.7 and 3.8 log CFU/g for 9×5×3 cm and 9×2.5×2 cm samples, respectively, while reductions in control fryer-browned samples were 0.6 log CFU/g, irrespective of product size. Compared to the untreated control, all tested antimicrobial treatments reduced (< 0.05) Salmonella counts, and the most effective treatment was CAR (0.15%)+POL (0.5%). Irrespective of antimicrobial treatment, pathogen reductions in fryer-browned samples were not (≥ 0.05) affected by product dimensions, whereas oven browning of 9×2.5×2 cm samples resulted in higher (< 0.05) reductions of Salmonella (reductions of 3.8 to >4.6 log CFU/g) than oven browning of 9×5×3 cm samples (reductions of 0.7 to 2.5 log CFU/g).

Significance: These findings should be useful in the selection of suitable antimicrobials, browning method and product sizes to reduce levels of Salmonella contamination in NRTE, surface-browned, frozen, breaded chicken products.