Coco Michael G, Vinson Joe A
Chemistry Department, Loyola Science Center, University of Scranton, 925 Ridge Row, Scranton, PA 18510, USA.
Antioxidants (Basel). 2019 Jan 14;8(1):22. doi: 10.3390/antiox8010022.
Popcorn, one of the most popular snack foods in the world, is known for being a high fiber, healthy food. Our research has found that commercial popcorn also contains significant amounts of the class of antioxidants known as phenolic acids. The total antioxidant power of raw and popped popcorn extract has been quantified using the Folin-Ciocalteu and FRAP assays. The polyphenols were found exclusively in the pericarp of the kernel completely bound to the oligosaccharide fiber matrix. An digestion study was also performed to predict the phenolic acids' bioavailability. On average, nine commercial popcorn samples contain 5.93 ± 0.92 mg/g of total polyphenols after alkaline hydrolysis and 2.66 ± 0.15 mg/g after digestion as measured by the Folin-Ciocalteu assay. Furthermore, the popping process was found not to significantly decrease the antioxidant capacity. These results indicate that a considerable amount of the bound polyphenols are bioaccessible. Due to the high levels of bioaccessible polyphenols, popcorn may be a significant source of dietary polyphenol antioxidants.
爆米花是世界上最受欢迎的零食之一，以其高纤维、健康的食品特性而闻名。我们的研究发现，市售爆米花还含有大量被称为酚酸的抗氧化剂。生爆米花和爆制后爆米花提取物的总抗氧化能力已通过福林-西奥尔特法（Folin-Ciocalteu）和铁还原抗氧化能力（FRAP）测定法进行了量化。发现多酚仅存在于玉米粒的果皮中，并且完全与低聚糖纤维基质结合。还进行了一项消化研究以预测酚酸的生物利用度。通过福林-西奥尔特法测定，平均而言，九个市售爆米花样品在碱性水解后含有5.93±0.92毫克/克的总多酚，消化后含有2.66±0.15毫克/克。此外，发现爆制过程不会显著降低抗氧化能力。这些结果表明，相当数量的结合多酚具有生物可及性。由于生物可及性多酚含量高，爆米花可能是膳食多酚抗氧化剂的重要来源。
