Reducing mycotoxin contamination in fruits

PATRIARCA, A.

Mendoza

Conferencia; MycoRed ISM conference; 2011

International Society for Mycotoxicology

Mycotoxin accumulation in fruits can occur in the field, at the time of harvest, postharvest and during storage. Fungal growth and subsequent mycotoxin production depends on the physical and chemical properties of the fruit, ripening state, presence of defects on the skin, as well as meteorological conditions during crop growth. Mycotoxins most commonly associated with fruits are those from the genera Aspergillus, Penicillium and Alternaria. The most frequently reported ones are OTA in grapes, grape-derived products, cocoa and coffee; aflatoxins in figs, citrus, dried fruits and nuts; and patulin in fresh fruits like apples, pears, apricots, peaches, grapes, fruit juices and fruit-derived products. The natural occurrence of Alternaria mycotoxins has been reported in tomatoes, apples, blueberries, grapes, citrus fruits and pecans. The best approach to prevent mycotoxin accumulation in fruits is to prevent mold growth at all stages of production. An integrated approach would include careful handling of fruit to prevent skin damage, and use of sanitary conditions in the fields, storage and processing facilities. Although direct consumption of visibly moldy fruits is unlikely, processed fruit products may contain significant amounts of these toxins if decayed fruit is not removed before processing or packaging. Fungicides are the primary means of controlling postharvest diseases in fruits. However, chemical synthetic fungicides can leave toxic residues, have a high persistence in the environment, and might lead to the appearance of resistant mutants of the target fungi. Besides, the excessive use of pesticides or the use of non-permitted ones is the major factor of rejection of fruits at the time of importation. The increasing concern of consumers and authorities for alternatives safer and environmental friendly has led to research the antifungal properties of several natural compounds. Plants extracts, essential oils, and oleoresins obtained from plant material have been studied for their effect on fungal growth and mycotoxin production. A great number of non-chemical methods and non-selective fungicide treatments have been proposed, such as antioxidant compounds, irradiation, ozone, organic acids, pulsed light, UV-C, etc. However, none of these alternatives has yet been massively applied. To achieve quality fresh-cut produce and the best possible safety levels it is necessary to implement improved strategies through introduction of or combination of sustainable techniques for sanitation. Hurdle technology, which involves the use of a combination of preservation approaches, has generally been successful in controlling pathogens and maintaining food quality during storage. Plant extracts in combination with other safe treatments are a good alternative for the prevention of fungal infection and mycotoxin contamination of fruits and could be applied before harvest, during processing, and during storage or shipping.