Factors that contribute to the botulinal safety of reduced-fat and fat-free process cheese products

• Published in: Journal of food protection Vol. 67; no. 8; pp. 1687 - 1693
• Main Authors: Glass, K.A, Johnson, E.A
• Format: Journal Article
• Language: English
• Published: Des Moines, IA International Association of Milk, Food and Environmental Sanitarians 01.08.2004
• Subjects: antibacterial properties; bacterial contamination; beta-glucans; Biological and medical sciences; botulinum toxin; cheesemaking; Clostridium botulinum A; Clostridium botulinum B; fat replacers; flavor enhancers; food additives; food contamination; Food industries; food pathogens; food storage; Fundamental and applied biological sciences. Psychology; General aspects; Hygiene and safety; ingredients; inoculum density; lactates; lipid content; low fat cheeses; Milk and cheese industries. Ice creams; processed cheeses; skim milk; sodium lactate; storage temperature; storage time; Dairy product; Fat; Safety; Processed cheese
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X-67.8.1687

The effects of fat, type of natural cheese, and adjunct process cheese ingredients were evaluated to determine factors that contribute to the botulinal safety of reduced-fat (RF) process cheese products stored at 30°C. In the first set of experiments, pasteurized process cheese products (PPCPs) were formulated using full-fat (FF) Cheddar, 30% RF Cheddar, or skim milk (SM) cheese as cheese-base types and were standardized to 59% moisture, pH 5.75, 2.8 or 3.2% total salts, and 15 to 19% fat. Subsequent trials evaluated the effect of fat levels and adjunct ingredients in PPCPs made with SM, RF, and FF cheese (final fat levels, less than 1, 13, and 24%, respectively). When fat levels of PPCPs were comparable (15.1, 19.1, and 16.2 for product manufactured with SC, RF, and FF cheese, respectively), botulinal toxin production was delayed for up to 2 days in PPCPs formulated with SM compared with RF or FF cheese; however, the effect was not statistically significant. When fat levels were reduced to less than 1% in SM PPCPs, toxin production was delayed 2 weeks in products made with SM compared with RF or FF cheese manufactured with 13 or 24% fat, respectively. The antibotulinal effect of adjunct ingredients varied among the products manufactured with different fat levels. Sodium lactate significantly delayed toxin production (P < 0.05) for all fat levels tested, whereas beta-glucan fat replacer did not delay toxin production. An enzyme-modified cheese used as a flavor enhancer significantly delayed toxin production (P < 0.05) in SM (less than 1% fat) products but had little to no inhibitory effect in RF (13% fat) and FF (24% fat) cheese products. Similarly, monolaurin increased the time to detectable toxin in SM products but was ineffective in RF or FF cheese products. These results verify that RF PPCPs exhibit greater safety than FF products and that safety may be enhanced by using certain adjunct ingredients as antimicrobials.