Control of Clostridium perfringens in a model roast beef by salts of organic acids during chilling

• Published in: Journal of food safety 2004-07, Vol.24 (2), p.95-108
• Main Authors: Juneja, V.K, Thippareddi, H
• Format: Article
• Language: English
• Subjects: antibacterial properties; bacterial contamination; bacterial spores; beef; Biological and medical sciences; Clostridium perfringens; cook-chill systems; cooling; food additives; food contamination; Food industries; Food microbiology; food pathogens; Fundamental and applied biological sciences. Psychology; ground beef; heat stress; hot water treatment; inoculum density; lactates; Meat and meat product industries; meat products; organic salts; pathogen survival; plate count; potato flour; pyrophosphates; roasts; salt concentration; sodium acetate; sodium chloride; sodium citrate; sodium diacetate; sodium lactate; spore-forming bacteria; vacuum packaging
• ISSN: 0149-6085; 1745-4565
• DOI: 10.1111/j.1745-4565.2004.tb00378.x

Control of Clostridium perfringens germination and outgrowth by the following salts of organic acids, sodium lactate [Purasal S/SP (Purasal); 1.50, 3.00 and 4.80%], sodium lactate supplemented with sodium diacetate [Purasal Opti.form (Optiform), 1.50, 3.00 and 4.80%], buffered sodium citrate [Ional (Ional), 0.75, 1.00 and 1.30]) and buffered sodium citrate supplemented with sodium diacetate [Ional Plus (Ional Plus), 0.75, 1.00 and 1.30%] was evaluated during continuous chilling of a model roast beef product. Beef rounds were ground through an 1/8" plate and NaCl, potato starch and potassium tetra pyrophosphate were added to final concentrations of 0.85, 0.25 and 0.20%, respectively, and mixed. Portions (250 g) of the meat were mixed with either Purasal (1.5, 3.0 or 4.8%), Optiform (1.5, 3.0 or 4.8%), Ional (0.75, 1.0 or 1.3%) or Ional Plus (0.75, 1.0 or 1.3%) along with a control that did not have any added antimicrobials. Each product (10 g) inoculated with C. perfringens spores (ca. 2.2 log10 spores/g) was packaged into vacuum bags (2 in. x 3 in.), vacuum sealed, heated to 60C within 1 h, and subsequently chilled from 54.4C to 7.2C in 18 or 21 h following exponential chilling rates. Products were sampled immediately after cooking to enumerate the C. perfringens populations (spores surviving heat treatment) and subsequent to chilling (total C. perfringens populations, including spores and vegetative cells resulting from germination and outgrowth of the spores). Chilling of cooked, model ground roast beef resulted in germination and outgrowth of C. perfringens spores; the population densities increased by 4.13 and 4.40 log10 CFU/g, following 18 and 21 h chill rates, respectively. Incorporation of Purasal (1.5-4.8%), Optiform (1.5B4.8%), Ional and Ional Plus (0.75-1.3%) substantially (P less than or equal to 0.05) inhibited germination and outgrowth of C. perfringens spores. Incorporation of antimicrobial ingredients resulted in less than or equal to 1.0 log10 CFU/g increase of the pathogen, except for model roast beef with Ional Plus at 0.75% concentration, following 18 h chilling rate. Similar results were obtained when 21 h chilling rate was followed, with roast beef containing ingredients (at all the concentrations) resulting in either reductions or less than or equal to 1.0 log10 CFU/g growth in total C. perfringens populations, except for Purasal and Ional Plus at 1.5 and 0.75% concentrations, respectively. Use of sodium salts of organic acids in form