Multi-mycotoxin production of cheese-derived fungal strains in vitro and in cheese models

With regards to the cheese industry, fungal growth is a widespread problem and usually producers make effort to avoid fungal development due to mycotoxin formation which adversely affects human health, reduces product quality, and causes economic losses. However, some fungal strains are also used as secondary cultures to obtain developed sensory properties in cheese as a result of the enzymatic activities of these strains. Non-commercial strains isolated from mould-ripened cheeses and/or autochthonous strains that spontaneously grown on cheese have much greater effect on the acquisition of appreciated sensory and textural characteristics in cheese. Autochthon strains particularly ensure a characteristic aroma of traditional cheeses that are not commercially produced and can be a potential adjunct providing not produce mycotoxins. In this study, 14 different Penicillium species previously isolated from traditional mould-ripened cheeses in cave were investigated for their mycotoxin production in both in vitro culture medium and in situ in cheese model. The results revealed that although individual strains produced various and higher amounts of mycotoxins in the culture medium, the number of produced mycotoxins and the obtained values were determined quite low in the cheese medium. The outcomes of this study highlight the mycotoxin production of strains depends on the composition and structure of the food matrix that they integrated and many different factors, such as presence of free fatty acids, antimicrobial and antifungal compounds of lactic acid bacteria, lack of carbohydrate sources, and sulfhydryl-containing compounds, such as cysteine and glutathione. Therefore, the method used in this study has a potential to be a new solution in the industry to produce mould-ripened cheeses under controlled conditions without any potential health risk.