The presence of aflatoxins, Alternaria toxins, ochratoxin A and patulin in fruits and their processed products such as juices, wines or cider is of high concern for human health due to their properties to induce severe acute and chronic toxicity at low dose levels. There are increasing reports on different and less obvious sources of alimentary exposure, in addition to the conventional studied and worldwide consumed fruit matrices for these mycotoxins, i.e. apple for patulin, grape for ochratoxin and fig for aflatoxins. Because these mycotoxins are very stable even to heat processes and because they can diffuse from the rotten parts to healthy parts of the fruits, their presence, especially in processed products, is unavoidable. The occurrence of mycotoxins in juices is of high concern because children are one of the main consumers and because juice consumption is greater than that of wine. Consequently, improved monitoring programs should be encouraged. The co-occurrence of these different mycotoxins in the same matrix is another point that requires more studies from a toxicological and occurrence point of view.
Many analytical methods have been developed for the determination of each group of these mycotoxins in different matrices. However there are no analytical methods for their simultaneous determination in fruits and their processed products. The development of rapid screening methods is also advisable in order to increase the number of monitored samples.
Recently considerable efforts have been made to set maximum levels in many countries for the most important mycotoxins and in the most frequent commodities where they occur. However not all the possibilities are regulated and no regulation exists for the Alternaria toxins. The observed occurrence of the latter toxins on numerous fruits and the high toxicity of these toxins suggest that they may pose a hazard comparable to that from more widely studied mycotoxins.
Apart from the regulatory controls, three main strategies have been adopted to decrease or even eliminate the presence of the mycotoxins in foods [24] and [86]: prevention of mycotoxin contamination during the pre-harvest and post-harvest periods, detoxification of mycotoxins present in foods and inhibition of mycotoxin absorption in the gastrointestinal tract. Preventive measures aimed at the inhibition of mycotoxin formation in agricultural products are the most effective approach for avoiding consumer exposure. Good farm management, methods of culture to improve plant vigour, use of insecticides, fungicides and biological control, irrigation and cultivar selection ensure plants less vulnerable to stress. Post-harvest contamination can be avoided by controlling moisture, temperature and microbiological, insect and animal pests. Detoxification of mycotoxins by different physical, chemical and biological methods are less effective and sometimes restricted because of concerns of safety, possible losses in nutritional quality of the treated commodities and cost implications. Some of the most promising interventions studied to date involve the use of microorganisms to reduce absorption of mycotoxins from consumed foods in the gastrointestinal tract. Experimentally, clear evidence exists regarding the ability of probiotic bacteria to decrease the potential bioavailability of certain mycotoxins in humans but further studies are needed.
Exposure to mycotoxins is a serious risk to human health especially in the developing world where the application of modern agricultural practices and the presence of a legislatively regulated food processing and marketing system are less developed.