Enhancing microbial safety and quality of milk with ultrasonication: Kinetics modeling of pathogenic bacteria and milk characteristics

Authors: KAUSHIK, ABHISHEK - National Institute Of Food Technology Entrepreneurship And Management(NIFTEM); TANEJA, NEETU KUMRA - National Institute Of Food Technology Entrepreneurship And Management(NIFTEM); JOSHI, AKANKSHA - National Institute Of Food Technology Entrepreneurship And Management(NIFTEM); Juneja, Vijay; SALAZAR, JOELLE - Chandigarh University; OBEROI, HARINDER SINGH - University Of Georgia

Submitted to: LWT - Food Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/30/2024
Publication Date: 5/31/2024
Citation: Kaushik, A., Taneja, N., Joshi, A., Juneja, V.K., Salazar, J.K., Oberoi, H. 2024. Enhancing microbial safety and quality of milk with ultrasonication: Kinetics modeling of pathogenic bacteria and milk characteristics. LWT - Food Science and Technology. https://doi.org/10.1016/j.lwt.2024.116287.
DOI: https://doi.org/10.1016/j.lwt.2024.116287

Interpretive Summary: Thermal treatment, commonly employed to extend the shelf-life of milk by eliminating microorganisms has adverse effects on milk quality. Therefore, we employed ultrasonication, a non-thermal inactivation method, for microbial inactivation as well as for retaining the nutritional value, texture and color of milk. The kinetic model developed will aid the food industry in predicting 5-log reduction of pathogens in milk without altering the organoleptic attributes. The findings will have significant implications for enhancing food safety, offering a tangible pathway toward safer and more nutritious dairy products. The insights gained from this research pave the way for more sustainable and efficient practices in the food industry, ultimately benefiting both producers and consumers alike.

Technical Abstract: This study examined the non-thermal inactivation kinetics of S. aureus NCDC109, E. coli EMC17, and Salmonella Typhimurium SMC25 in milk using ultrasonication and also, assessed its impact on milk's physicochemical properties. Various ultrasonic amplitudes (40, 50, 60, and 70%) and time intervals (0-30 min) post-inoculation were applied to milk samples. The highest logarithmic reduction of 6.12, 6.19, and 5.68 for S. aureus NCDC109, E. coli EMC17, and Salmonella Typhimurium SMC25, respectively, was achieved with 70% amplitude for 30 min. Survivor curve modelling, employing the Weibull model, exhibited better fit compared to the linear model, as indicated by lower RMSE, MSE, SSE, and AIC values. The Weibull model accurately predicted D-values for all strains and treatment amplitudes, with Af values ranging from 1.02 to 1.01 and Bf values of either 1.00 or 1.01. The time required for a 5-log reduction decreased from 46.05 min for 40% amplitude of E. coli EMC17 to 20.01 min for 70% amplitude. Furthermore, ultrasonication preserved milk's physicochemical properties, including particle size, zeta potential, color, pH, and viscosity. This study underscores the potential of ultrasonication as a powerful tool in the realm of food processing, offering an innovative approach to mitigate bacterial contamination in milk without compromising its essential nutritional attributes. It offers a valuable tool for predicting and validating responses using growth kinetic models under specific ultrasonic conditions for pathogenic microorganisms like E. coli, S. Typhimurium, and S. aureus in milk. These findings hold promise for controlling bacterial contaminations and optimizing milk processing techniques.