196: Effect of Fetal Bovine Serum in Cellular Agriculture Media on the Thermal Tolerance of Foodborne Pathogens

Introduction

Amid growing concerns about animal welfare and the environmental impact of traditional livestock agriculture, cellular agriculture in food production is emerging as a sustainable alternative. Despite challenges such as inconsistent ingredients and ethical dilemmas, fetal bovine serum (FBS) has been commonly employed in Leibovitz's L-15 (L-15) as a universal growth supplement of cell culture media.

Methods

This study evaluated the thermal tolerance of foodborne pathogens cultured in L-15 with varying FBS concentrations (0%, 2%, and 10%) at 36°C, subjecting to thermal treatments at 55, 60, 65, 70, and 75°C.

Results

This study revealed that the addition of FBS to L-15 media promotes the proliferation of all tested foodborne pathogens. The highest thermal inactivation gradients were observed in cultures containing 10% FBS, suggesting that the presence of 10% FBS plays a significant role in increasing bacterial susceptibility to thermal treatment. E. coli O157:H7 cultured in 10% FBS and subjected to 55°C exhibited the highest D-value compared to those cultured in 0% and 2% FBS. However, Salmonella enterica cultured in 10% FBS showed opposite trends with the lowest D-value. Among the bacteria evaluated, E. coli O157:H7 exhibited the highest z-value across all tested media, signifying its exceptional thermal tolerance compared to the other bacteria. Gram-negative bacteria (E. coli O157:H7 and Salmonella enterica) had decreasing z-values with higher FBS, while Gram-positive bacteria (Listeria monocytogene and Staphylococcus aureus) showed opposite trends.

Significance

While acknowledging the need for further research, this study underscores the substantial impact of serum concentrations on bacterial responses, particularly within cell culture-based food processing and storage.

Authors: Chyer Kim, Eunice Ndegwa, Ramesh Dhakal, Samantha Michaud, Allissa Riley, and Yixiang Xu