Non-flavonids important as phytoalexins. Includes resveratrol. Justin Beaver, 2016
Stilbenoids are a diverse class of compounds with the general structural form C6-C2-C6. They are naturally occurring and can be found in variety of plant species including Vitis vinifera (grapes). Research has shown that stilbenoids are “phytoalexins,” which means a plant synthesizes these compounds as a response to microbial or abiotic stress, namely fungal infection and exposure to UV-radiation. To winemakers, this function of combating external stress is extremely useful considering grey mold and sun exposure are common issues in food production. The maintenance of the grapevine is ultimately made simpler by these protective chemicals. In addition, stilbenoids are by nature antioxidants. In theory, this could help with the stabilization of a wine by preventing oxidation. In practice, however, stilbenoid activity in wine has been shown to be relatively static and does not significantly contribute to the reduction of oxidative compounds.
Resveratrol is likely the most popularized of all stilbenoids. In 1992, a study reported that resveratrol seemed to inhibit tumor growth in certain animal models. Since then, there has been a terrific spike in the amount of research conducted on this compound. Unfortunately, the levels of resveratrol reported in wine versus the amounts used in these health studies are significantly different. The average concentration of resveratrol in red wine is 1.1-2.7mg/L. In a study out of the University of Illinois, it was suggested that resveratrol may play a crucial role in the prevention of heart disease, but the level of exposure in test mice were 8mg/kg of body weight. If translatable to humans, a 150-pound individual would need about 544mg of resveratrol for an effect to occur. To obtain this quantity of resveratrol from red wine, one would have to consume about 266 bottles. In many other health-related studies on resveratrol, the quantities of exposure are also significantly above what a person would ingest from a glass or two of wine. As it stands, research suggests that stilbenoids’ importance in the winemaking process is limited to their role as a phytoalexin in grapevines.
Reference
Chong, Julie, Anne Poutaraud, and Philippe Hugueney. 2009. “Metabolism and roles of stilbenes in plants.” Plant Science, Vol. 177, pp. 143–155.
Jeandet, Philippe, Roger Beiss, Mohamed Sbaghi, Philippe Meunier, and Philippe Trollat. 1995. “Resveratrol Content of Wines of Different Ages: Relationship With Fungal Disease Pressure in the Vineyard.” Am. J. Enol. Vitic., Vol. 46, pp. 1-4.
Meishiang, Jang, Lining Cai,* George O. Udeani,Karla V. Slowing, Cathy F. Thomas, Christopher W. W. Beecher, Harry H. S. Fong, Norman R. Farnsworth, A. Douglas Kinghorn, Rajendra G. Mehta, Richard C. Moon, John M. Pezzuto. 1997. “Cancer Chemopreventive Activity of Resveratrol, a Natural Product
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Pawlus, Allison D., Pierre Waffo-Teguo, Jonah Shaver, and Jean-Michel Merillion. 2012. “Stilbenoid Chemistry from wine and the genus vitis: a review.” International Journal of Wine and Science. Vol. 46, Issue 2, pp. 57-111.