Fungi and mycotoxins in vineyards and grape products

• Published in: International journal of food microbiology Vol. 119; no. 1; pp. 84 - 88
• Main Authors: Hocking, Ailsa D., Leong, Su-lin L., Kazi, Benozir A., Emmett, Robert W., Scott, Eileen S.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 20-10-2007; Elsevier
• Subjects: Aspergillus - growth & development; Aspergillus - metabolism; Aspergillus carbonarius; Aspergillus niger; Aspergillus niger - growth & development; Aspergillus niger - metabolism; Beverages - analysis; Biological and medical sciences; Botrytis; crop management; disease and pest management; dried fruit; Food Contamination - analysis; Food Contamination - prevention & control; Food Handling - methods; Food industries; Food Microbiology; food pathogens; food processing; Food toxicology; Fundamental and applied biological sciences. Psychology; grape juice; Grapes; irrigation; mildews; Ochratoxin; Ochratoxins - analysis; Ochratoxins - biosynthesis; Ochratoxins - toxicity; on-farm food safety; Plant Diseases - microbiology; plant pathogenic fungi; plant rots; pruning; Reduction; risk management; table grapes; toxic substances; Vineyard management; vineyards; Vitaceae; viticulture; Vitis - chemistry; Vitis - microbiology; Wine; Wine - analysis; wine grapes; winemaking; Wine; Ochratoxin; Reduction; Vineyard management; Grapes; Fungi; Alcoholic beverage; Toxin; Fruit; Grape; Mycotoxin
• ISSN: 0168-1605; 1879-3460
• DOI: 10.1016/j.ijfoodmicro.2007.07.031

Many fungi may occur on grapes during growth in the vineyard, but the main concern from the viewpoint of mycotoxin contamination is the black Aspergilli,
Aspergillus carbonarius and
A. niger. These fungi are capable of producing ochratoxin A (OA) which may contaminate grapes and grape products such as wine, grape juice and dried vine fruit. Understanding the ecology and physiology of the black Aspergilli can provide tools for management of OA at all stages of grape production and processing. In the vineyard, careful management of cultivation, irrigation and pruning can assist in minimising the levels of black Aspergilli in the soil, which in turn, can minimise contamination of grapes by these fungi. Minimising damage to grapes on the vine by the use of open vine canopies, grape varieties with resistance to rain damage and by the management of insect pests and fungal diseases (
e.g., mildew, Botrytis bunch rot) can reduce the incidence of
Aspergillus rot in mature berries. The risk of OA in table grapes can be minimised by careful visual inspection to avoid damaged and discoloured berries. In wine, harvesting grapes with minimal damage, rapid processing and good sanitation practices in the winery assist in minimising OA. During vinification, pressing of grapes, and clarification steps which remove grape solids, grape proteins and spent yeast can also remove a significant proportion of OA. For dried vine fruit production, avoiding berry damage, rapid drying, and final cleaning and sorting to remove dark berries can reduce overall OA levels in finished products.