Analysis of Mycotoxin and Secondary Metabolites in Commercial and Traditional Slovak Cheese Samples.

Luana Izzo,Michael Sulyok,Petra Mikušová,Alberto Ritieni,Sonia Lombardi

doi:10.3390/toxins14020134

Abstract

Cheese represents a dairy product extremely inclined to fungal growth and mycotoxin production. The growth of fungi belonging to Aspergillus, Penicillium, Fusarium, Claviceps, Alternaria, and Trichoderma genera in or on cheese leads to undesirable changes able to affect the quality of the final products. In the present investigation, a total of 68 types of commercial and traditional Slovak cheeses were analyzed to investigate the occurrence of fungal metabolites. Altogether, 13 fungal metabolites were identified and quantified. Aflatoxin M1, the only mycotoxin regulated in milk and dairy products, was not detected in any case. However, the presence of metabolites that have never been reported in cheeses, such as tryptophol at a maximum concentration level from 13.4 to 7930 µg/kg (average: 490 µg/kg), was recorded. Out of all detected metabolites, enniatin B represents the most frequently detected mycotoxin (0.06–0.71 µg/kg) in the analyzed samples. Attention is drawn to the lack of data on mycotoxins’ origin from Slovak cheeses; in fact, this is the first reported investigation. Our results indicate the presence of fungal mycotoxin contamination for which maximum permissible levels are not established, highlighting the importance of monitoring the source and producers of contamination in order to protect consumers’ health.

Highlights

Fungi are the major producers of secondary toxic metabolites, which represent the main cause of food spoilage
enniatin B (ENN B) was reported in all samples (100%, n = 68); its concentration was low compared with other metabolites (0.06 to 0.17 μg/kg) and tryptophol; the second most frequent detected metabolite, present in 30.8% of commercial cheeses (n = 12) and 34.5% of traditional cheeses (n = 10)
Mycotoxins are toxic compounds produced by several molds belonging to the main genera of fungi—Aspergillus, Penicillium, Fusarium, Claviceps, Alternaria, Stachybotrys and many others—which have a wide variety of properties that influence our common life [1]

Summary

Introduction

Fungi are the major producers of secondary toxic metabolites, which represent the main cause of food spoilage. Rumen flora can change a number of mycotoxins into metabolites that are less biologically inactive at common exposure levels. This does not apply to all mycotoxins that contaminate feed materials [6]. It is concluded that the penetration depends on the type of cheese and the type of mycotoxin It has been reported by several authors that toxin concentrations and visible mold colonies may not always correlate [9,10,11,12]

Methods

Results

Conclusion