Quantitative microbial spoilage risk assessment of plant-based milk alternatives by Geobacillus stearothermophilus in Europe

Ourania Misiou; Konstantinos Koutsoumanis; Jeanne-Marie Membré

doi:10.1016/j.foodres.2023.112638

Quantitative microbial spoilage risk assessment of plant-based milk alternatives by Geobacillus stearothermophilus in Europe

Food Res Int. 2023 Apr:166:112638. doi: 10.1016/j.foodres.2023.112638. Epub 2023 Feb 24.

Authors

Ourania Misiou¹, Konstantinos Koutsoumanis¹, Jeanne-Marie Membré²

Affiliations

¹ Department of Food Science and Technology, Faculty of Agriculture, Aristotle University of Thessaloniki 54124 Thessaloniki, Greece.
² Oniris, INRAE, Secalim, Site de la Chantrerie, CS 40706, 44307 Nantes Cédex 3, France. Electronic address: jeanne-marie.membre@oniris-nantes.fr.

PMID: 36914335
DOI: 10.1016/j.foodres.2023.112638

Abstract

Geobacillus stearothermophilus is one of the predominant spoilers of UHT-treated food products, due to its extremely heat-resistant spores. However, the surviving spores should be exposed to temperature higher than their minimum growth temperature for a certain time to germinate and grow to spoilage levels. Considering the projected temperature increase due to climate change, the events of non-sterility during distribution and transportation are expected to escalate. Hence, the aim of this study was to build a quantitative microbial spoilage risk assessment (QMRSA) model to quantify the risk of spoilage of plant-based milk alternatives within Europe. The model consists of four main steps: 1. Initial contamination of raw materials 2. Heat inactivation of spores during UHT treatment 3. Partitioning 4. Germination and outgrowth of spores during distribution and storage. The risk of spoilage was defined as the probability of G. stearothermophilus to reach its maximum concentration (N_max = 10^7.5 CFU/mL) at the time of consumption. The assessment was performed for North (Poland) and South (Greece) Europe, and the risk of spoilage was estimated for the current climatic conditions and a climate change scenario. Based on the results, the risk of spoilage was negligible for the North European region, while the risk of spoilage in South Europe was 6.2 × 10^-3 95% CI (2.3 × 10^-3;1.1 × 10^-2) under the current climatic conditions. The risk of spoilage was increased for both tested countries under climate change scenario; from zero to 1.0 × 10^-4 in North Europe, risk multiplied 2 or 3 in South Europe depending on air conditioning implementation at consumer's place. Therefore, the heat treatment intensity and the use of insulated trucks during distribution were investigated as mitigation strategies and led to significant reduction of the risk. Overall, the QMRSA model developed in this study can support risk management decisions of these products by quantify the potential risk under current climatic conditions and climate change scenarios.

Keywords: Climate change; Probabilistic modelling; Risk analysis; Risk of spoilage; Second order Monte Carlo simulation; Sensitivity analysis; Uncertainty; Variability.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Europe
Food Microbiology*
Geobacillus stearothermophilus*
Milk
Risk Assessment / methods