MOLECULAR AND GENETIC APPROACHES TO SUPPRESSING FUNGAL PATHOGENS AND MYCOTOXIN CONTAMINATION
Location: Plant Mycotoxin Research
Title: Health Aspects and Anti-Aflatoxigenic Activity of Phytochemicals in Tree Nuts
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: April 2, 2008
Publication Date: March 23, 2009
Citation: Molyneux, R.J., Mahoney, N.E., Kim, J.H., Campbell, B.C. 2009. Health Aspects and Anti-Aflatoxigenic Activity of Phytochemicals in Tree Nuts. In: Alasalvar, C., Shahidi, F., Editor Tree Nuts: Composition, Phytochemicals and Health Effects, Edition. Boca Raton, FL: CRC Press. p. 95-107.
Interpretive Summary: This book chapter describes the health benefit of eating tree nuts (almonds, pistachios and walnuts) as part of a healthy diet. These include lower levels of cholesterol and reduced risk of heart disease. However, concerns have arisen because of the potential formation of cancer-causing compounds by molds that may infect the nuts. These compounds, known as aflatoxins, are strictly regulated in international trade and their presence can result in considerable economic losses to producers and exporters. Factors present in nuts that may suppress formation of aflatoxins have been identified and methods to increase resistance of the nuts to contamination are described.
Tree nuts, while not generally regarded as a staple food, are particularly appreciated by consumers for their flavor and convenience. Most consumers regard nuts as "natural" foods and have little concern for adverse or deleterious effects other than occasional allergenicity in some individuals. Development of off-flavors from rancidity and infection with spoilage microorganisms (generally Aspergillus niger, Penicillium spp., and Rhizopus spp.) are so obvious that such nuts are usually discarded and not eaten. Nuts contain high levels of protein, fiber, and dietary fats, which in association with their pleasant flavor and convenience, has led to the recommendation that they should be an essential part of a healthy diet. Tree nuts are an extremely valuable agricultural commodity in national and international trade. A serious constraint on the marketing of tree nuts, is the potential presence of aflatoxins, which are highly regulated because of food safety concerns. In 2005, 94% of the rapid alerts or notifications from the EC Rapid Alert System for Food and Feed (RASFF) for mycotoxins in tree nuts were for aflatoxins, with 28 for almonds and 13 for pistachios from the U.S. While this is a small number relative to the total of 827 alerts for all mycotoxins in tree nuts, it represents considerable economic loss to California producers and exporters, due to lost revenue, return or reprocessing of the shipment and increased sampling of subsequent imports.