A study published in Food Research International used an in vitro digestion model to determine the bio accessibility of wine polyphenols. In vitro models simulate the gastro intestinal tract condition by adjusting the ionic strength and pH, as well as addition of enzymes, bile salts and even fermentation reactions to simulate colon conditions. The Effects of drinking amount and patterns of wine consumption on the digestive characteristics and bio availability of wine polyphenols under in vitro gastrointestinal digestion were investigated. Wine polyphenols released well during mouth and stomach digestion, and the release rates in the “serumavailable” fraction, “colon-available” fraction, and after the colon were much lower.
Red wine showed a higher biological activity than white wine, but white wine had a better bio availability than red wine, especially under binge drinking. The bio availability of most polyphenols decreased as the drinking amount increased, indicating that drinking larger volumes of wine did not increase the bio availability of polyphenols. Additionally, the relevant biological activities did not increase as the drinking amount increased. Drinking after a meal showed significantly better results than drinking before a meal in most of the tests. Hence, in order maximise the beneficial effect of wine polyphenols on human health, a moderate consumption of wine and drinking after a meal is better.
Source: Letting wine polyphenols functional: Estimation of wine polyphenols bioaccessibility under different drinking amount and drinking patterns. XiangyuSun, X Chenga1J ZhangaY Ju,Z Que,X Liao,F Lao,Y Fang,T Ma. Food Research International Vol.127, Jan. 2020.