Food Quality and Safety (FoQuS) Research Group, Department of Food Engineering, Hacettepe University, Ankara, Turkey.
J Sci Food Agric. 2022 Nov;102(14):6502-6510. doi: 10.1002/jsfa.12017. Epub 2022 Jun 2.
Bound antioxidants are distinguished by their strong potential to defend the body against oxidative stress. Cereal bran fractions contain antioxidant compounds bound to dietary fiber, but this only occurs to a limited extent. Increasing the quantity of bound antioxidant compounds using soluble phenolic compounds is thought to be a possible method for designing cereal-based dietary fibers with high antioxidant potential. Certain cereal bran samples (wheat, oat, rye, and rice) were reacted with different concentrations of beverages (green tea infusion, black tea infusion, espresso, and red wine), rich in various soluble phenolic compounds. The interactive effects of parameters (time, temperature, and pH) and the optimum conditions for the reaction were determined using response surface methodology.
Green tea infusion (30 g·L ) was found to be the most effective beverage. The pH rather than the time and temperature had significant (O p < 0.0001) effects on the reaction. Neutral or slightly alkaline conditions (pH 7.0-7.9) and mild temperatures (at about 50 °C) were found to be optimum to increase the antioxidant capacity of cereal bran samples. The total antioxidant capacity of oat bran treated with green tea infusion under optimum conditions (53.3 °C, pH 7.4, 60.0 min) reached 226.42 ± 0.88 mmol Trolox equivalent·kg . The free amino groups in cereal bran were also found to decrease (32-95%) after treatment.
It is possible to design functional cereal-based dietary fibers, rich in bound antioxidant compounds through treatment with green tea infusion under optimum conditions. © 2022 Society of Chemical Industry.
束缚型抗氧化剂因其具有强大的抵御氧化应激的潜力而备受关注。谷物麸皮部分含有与膳食纤维结合的抗氧化化合物，但这种结合程度有限。使用具有高抗氧化潜力的可溶性酚类化合物增加束缚型抗氧化化合物的数量被认为是一种可能的设计方法。用富含各种可溶性酚类化合物的不同浓度的饮料（绿茶浸提液、红茶浸提液、浓咖啡和红葡萄酒）与特定的谷物麸皮样品（小麦、燕麦、黑麦和大米）进行反应，确定了参数（时间、温度和 pH）的交互作用和反应的最佳条件使用响应面法。
绿茶浸提液（30g·L）是最有效的饮料。pH 值而不是时间和温度对反应有显著影响（O p<0.0001）。发现中性或略带碱性条件（pH 7.0-7.9）和温和的温度（约 50°C）是增加谷物麸皮样品抗氧化能力的最佳条件。在最佳条件（53.3°C，pH 7.4，60.0 min）下用绿茶浸提液处理的燕麦麸皮的总抗氧化能力达到 226.42±0.88mmol Trolox 当量·kg。谷物麸皮中的游离氨基酸基团在处理后也发现减少（32-95%）。
通过在最佳条件下用绿茶浸提液处理，有可能设计富含束缚型抗氧化化合物的功能性谷物膳食纤维。© 2022 化学工业协会。
