Assessment of trans-cinnamaldehyde and eugenol assisted heat treatment against Salmonella Typhimurium in low moisture food components. (June 2023)

• Record Type: Journal Article
• Authors: Ding, Qiao; Ge, Chongtao; Baker, Robert C.; Buchanan, Robert L.; Tikekar, Rohan V.
• Is Part Of: Food microbiology. Volume 112(2023)
• Publication Date: 2023-06
• Subjects: Food components -- Water activity -- GRAS compounds -- Thermal inactivation -- Metabolic activity -- Membrane properties; Food Microbiology -- Periodicals; Aliments -- Microbiologie -- Périodiques; Food -- Microbiology; Periodicals; Food -- Microbiology -- Periodicals; Food contamination -- Periodicals; 664.001579
• DOI: 10.1016/j.fm.2023.104228
• Languages: English
• ISSNs: 0740-0020

Abstract

Abstract: Increased thermal resistance of Salmonella at low water activity (aw ) is a significant food safety concern in low-moisture foods (LMFs). We evaluated whether trans -cinnamaldehyde (CA, 1000 ppm) and eugenol (EG, 1000 ppm), which can accelerate thermal inactivation of Salmonella Typhimurium in water, can show similar effect in bacteria adapted to low aw in different LMF components. Although CA and EG significantly accelerated thermal inactivation (55 °C) of S. Typhimurium in whey protein (WP), corn starch (CS) and peanut oil (PO) at 0.9 aw, such effect was not observed in bacteria adapted to lower aw (0.4). The matrix effect on bacterial thermal resistance was observed at 0.9 aw, which was ranked as WP > PO > CS. The effect of heat treatment with CA or EG on bacterial metabolic activity was also partially dependent on the food matrix. Bacteria adapted to lower aw had lower membrane fluidity and unsaturated to saturated fatty acids ratio, suggesting that bacteria at low aw can change its membrane composition to increase its rigidity, thus increasing resistance against the combined treatments. This study demonstrates the effect of aw and food components on the antimicrobials-assisted heat treatment in LMF and provides an insight into the resistance mechanism. Highlights: Effect of the antimicrobial-assisted heat treatment reduces at lower water activity. Bacterial resistance varies across different food matrices at the same water activity. Treatment effect on bacterial metabolic activity varies across different matrices. Changed membrane composition increases its rigidity at lower water activity.