Identification and risk characterization of moulds in fruit and sweetened foods

Main research question/goal

How can we reduce the patulin contamination of apple products? How do molds enter food during the industrial production processes of sweet fillings? Which measures are effective to extend the shelf life of sweets? Molds not only cause spoilage of food (economical loss), but certain molds might produce mycotoxins such as patulin (risk for human health). Patulin is formed during storage of specific fruits such as apples and can occur in products containing fruit. Contamination of sweet products with xerophilic molds results in a limited microbiological shelf life. We concentrate on the critical factors and storage conditions that may lead to patulin production and improved monitoring of contamination sources and risks of contaminating sweets with xerophilic molds.

Research approach

We analyze the patulin-producing capacity of Penicillium expansum under different storage conditions. We optimize a method for patulin analysis on apple puree medium and apple products and develop a molecular technique to study the expression of the idh gene involved in the biosynthesis of patulin. We determine the most critical factors for production of patulin in apples and the most important pathways that xerophilic molds use to enter and contaminate sweets in Belgium. For this purpose classical as well as molecular methods are used to isolate and identify the most important xerophilic molds from ingredients and the production environment.

Relevance/Valorisation

The results of this project were spread via posters and oral presentations on national and international conferences and are published in public and international peer-review journals. In addition, relevant sectors, companies, organizations and competent authorities were informed via popularized publications and oral presentations. Nuts are an important source of xerophilic fungi in chocolate confectionary. Humid heating seems very effective to reduce mold contamination. Low temperature in combination with controlled atmosphere results in a low production of patulin and a downregulation of the expression of the idh gene. The validated method for patulin analysis in apple products will be offered as one of the ILVO services. This project was part of the PhD thesis of Nikki De Clercq.

External partner(s)
Ugent - Fac. Bio-ingenieurswetenschappen