# title
Simulating Listeria monocytogenes Cross-Contamination of Fresh Avocado in a Dry Pack Line: A Hybrid Approach to Food Safety

# abstract
ABSTRACT  This study addresses the urgent need for simulationbased tools that evaluate corrective actions against microbial crosscontamination in food packing facilities. It presents a novel Food Safety AgentBased Simulation (FSABS) that integrates predictive microbiology with discrete event simulation (DES) to track and predict  Listeria monocytogenes  behavior along a postharvest Hass avocado dry processing line. The model combines the operational efficiency of DES with the biological realism of agentbased modeling, enabling a comprehensive understanding of how  L. monocytogenes  spreads in complex processing environments. The objectives of this study were threefold: (1) to track and predict microbial crosscontamination in the avocado dry processing line; (2) to integrate microbiological interactions with supply chain logistics; and (3) to enhance food safety by providing actionable insights for crosscontamination risk mitigation. Developed in NetLogo, the simulation treats avocados as mobile agents moving across a gridbased facility, each carrying attributes like contamination levels and transfer probabilities. This approach models both logistical flow and microbial dynamics, offering insights into how contamination propagates and how interventions might contain it. Validation with realworld data showed that crosscontamination remains limited at low initial loads (0.11.5 log CFU) but increases sharply beyond a 3.0 log CFU thresholdhighlighting a tipping point where control measures become ineffective. Scenario testing revealed that increasing sampling frequency and sample size improves contamination detection and reduces variability. The model emphasizes the importance of early intervention, frequent sanitation, and strategic sampling in mitigating contamination risks. This hybrid tool provides a robust decisionsupport framework for improving operational integrity and food safety in avocado packing facilities.

# authors[].organizations[].label
Texas A&M Engineering Experiment Station (TEES)

# authors[].organizations[].label
College of Agriculture and Life Sciences

# authors[].organizations[].label
Institute for Engineering Education and Innovation

# authorList[]
Madamba, T., Moreira, R. G., Castillo, A., & Mohebbi, Z.