Careful processing can preserve important biological activities of blueberries despite changing the blueberry (poly)phenol composition and plasma metabolite profile.

Evaluation of the total antioxidant capacity of solid matrices without extraction steps is a very interesting 10 alternative for food researchers and also for food industries. These methodologies have been denominated by QUENCHER from 11 quick, easy, new, cheap, and reproducible assays. To demonstrate and highlight the validity of QUENCHER (Q) methods, values 12 of Q-method validation were showed for the first time, and they were tested with products of well-known different chemical The most commonly applied in vitro TAC methodologies 42 are based on diverse strategies to evaluate (1) the reducing 43 ability of antioxidants, such as the Folin−Ciocalteu (FC) and 44 ferric reducing/antioxidant power (FRAP) assays; (2) the 45 scavenging of stable free radicals by antioxidants, including the 46 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) 47 and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays; and (3) 48 the scavenging of short-lived radicals by competition 49 mechanisms, such as peroxyl radicals in the oxygen radical

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The roasting process induces chemical changes in coffee beans that strongly affect the antioxidant activity of coffee. In this study, the polyphenol and melanoidin contents and the antioxidant activity of three instant coffees with different roasting degrees (light, medium, and dark) were assessed. Coffee brews were separated into fractions, and the potential biological activity of the melanoidins was evaluated by simulating their gastrointestinal digestion. Total antioxidant capacity, hydroxyl radical scavenger activity, lipid peroxidation inhibition capacity, and protection against DNA oxidative damage (in vitro and ex vivo genoprotective effects) were determined. We report that instant coffee has a high total antioxidant capacity and protective effect against certain oxidative stress biomarkers (lipids and DNA), although this capacity decreases with the roasting degree. Our study confirms the hypothesis that several of the polyphenols present in coffee may become part of the melanoidins generated during roasting. Furthermore, the elevated genoprotective effect of melanoidin-digested fractions is noteworthy.