Comparative analysis of strawberry total phenolics via Fast Blue BB vs. Folin-Ciocalteu: Assay interference by ascorbic acid

► Strawberry phenolics were determined by Folin-Ciocalteu and Fast Blue BB assays. ► Folin-Ciocalteu is an indirect assay and Fast Blue BB is a direct assay of phenolics. ► Fast Blue BB measured 3-fold greater total phenolics than Folin-Ciocalteu. ► Fast Blue BB had r = 0.80 with phenolics and no ascorbic acid interference. ► Folin-Ciocalteu had r = 0.20 with phenolics and r = 0.64 with ascorbic acid.