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The total antioxidant capacity of three beverages based on fruit juice, milk and cereals, intended for infants and young children up to 3 years of age was evaluated by two methods Trolox Equivalent Antioxidant Capacity and Oxygen Radical Absorption Capacity. Results: According to the total antioxidant values obtained by both methods, the beverages can be ranked as follows: grape-orange-banana > peach-apple > pineapple-banana. Ascorbic acid was the main contributor (60%) to the total antioxidant capacity, while the contribution of skimmed milk was less than 1.2%. After one month of storage at -20 ºC, significant losses (p < 0.05) in total antioxidant capacity were found, though these were lower than 3% and therefore lacked nutritional significance. The bioaccessible fractions (maximum soluble fraction in simulated gastrointestinal media) of the beverages, obtained by in vitro gastrointestinal digestion, had antioxidant activities significantly lower (p < 0.05) than the original beverages, though the loss of antioxidant activity was always lower than 19% -thus indicating the stability of the total antioxidant capacity under the applied conditions. Conclusions: The total antioxidant capacity values of the bioaccessible fraction show that most antioxidants are available for absorption after digestion, and might contribute to the beneficial effects attributed to antioxidants.
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