In the present work, an
automatic flow procedure based on multi-syringe flow injection analysis wasdeveloped for the assessment of Folin-Ciocalteu reagent (FCR) reducing capacity in several typesof food products using gallic acid as the standard. Different strategies for mixing of sample and reagentwere tested (continuous flow of FCR, merging zones, and intercalated zones approaches); lowerreagent consumption and higher determination throughput were attained for the merging zonesapproach (100
L of sample + 100
L of FCR). The application of the proposed method to compoundswith known antioxidant activity (both phenolic and nonphenolic) and to samples (wines, beers, teas,soft drinks, and fruit juices) provided results similar to those obtained by the conventional batch method.The detection limit was 0.6 mg L
-1, and the determination frequency was about 12 h
-1. Goodrepeatability was attained (RSD < 1.3%,
n = 10).Keywords: Multi-syringe flow injection; Folin-Ciocalteu reducing capacity; phenolic compounds