In winemaking, the juice from the grapes may not be the only useful product -- a new study suggests the leftover seeds and skins from the winemaking process are high in antioxidants and could be added to other products to make them more nutritious.
Specifically, researchers found that the pomace from pinot noir and merlot wines are high in antioxidant dietary fibers. To convert the pomace into a form that could be used in other foods, they found that a cost-effective method of doing so is to dry the pomace in an oven, and then air dry it.
"Overall, 40 [degrees] C oven and ambient air dry are highly acceptable by considering the amount of retention of most measured bioactive compounds and their much less cost compared with freeze dry, thus may be employed in commercial application of drying large quantity of wine processing byproducts," they wrote in the study, published in the Journal of Food Science.
The researchers also found that pomace extract had some antibacterial properties, working effectively against the L. innocua bacteria.
"Based on our results, Pinot Noir and Merlot pomace can be considered as ADF [antioxidant dietary fiber] to be used as functional ingredient incorporated into various food products for promoting human health," they wrote.
Another food that you'd never expect to be high in antioxidants? (Plain) popcorn, according to research presented earlier this year at a meeting of the American Chemical Society. In that study researchers from the University of Scranton found that popcorn's hull is jam-packed with antioxidants called polyphenols.