Intraspecific variability in heat resistance of fungal conidia. (June 2022)

• Record Type: Journal Article
• Authors: van den Brule, Tom; Punt, Maarten; Seekles, Sjoerd J.; Segers, Frank J.J.; Houbraken, Jos; Hazeleger, Wilma C.; Ram, Arthur F.J.; Wösten, Han A.B.; Zwietering, Marcel H.; Dijksterhuis, Jan; den Besten, Heidy M.W.
• Is Part Of: Food research international. Volume 156(2022)
• Publication Date: 2022-06
• Subjects: Strain variability -- Thermal inactivation kinetics -- Paecilomyces variotii -- Aspergillus niger -- Penicillium roqueforti -- Food spoilage; Food -- Analysis -- Periodicals; Food industry and trade -- Periodicals; Food industry and trade -- Canada -- Periodicals; Food Technology -- Periodicals; Food -- Periodicals; Food-Processing Industry -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Industrie et commerce -- Canada -- Périodiques; Aliments -- Recherche -- Périodiques; Food industry and trade; Canada; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.foodres.2022.111302
• Languages: English
• ISSNs: 0963-9969

Abstract

Graphical abstract: Highlights: Heat resistance of A. niger, P. roqueforti and P. variotii was characterized. Experimental, biological and strain variabilities were quantified. Strain variability of the three fungal species was comparable. Degree of intraspecies variability was rather similar for bacterial and fungal species. Abstract: Microbial species are inherently variable, which is reflected in intraspecies genotypic and phenotypic differences. Strain-to-strain variation gives rise to variability in stress resistance and plays a crucial role in food safety and food quality. Here, strain variability in heat resistance of asexual spores (conidia) of the fungal species Aspergillus niger, Penicillium roqueforti and Paecilomyces variotii was quantified and compared to bacterial variability found in the literature. After heat treatment, a 5.4- to 8.6-fold difference in inactivation rate was found between individual strains within each species, while the strain variability of the three fungal species was not statistically different. We evaluated whether the degree of intraspecies variability is uniform, not only within the fungal kingdom, but also amongst different bacterial species. Comparison with three spore-forming bacteria and two non-spore-forming bacteria revealed that the variability of the different species was indeed in the same order of magnitude, which hints to a microbial signature of variation that exceeds kingdom boundaries.