title: Influence of gelatinization on the extraction of phenolic acids from wheat fractions.
abstract: The effect of gelatinization on the analysis of phenolic acids from wheat bran, whole-wheat, and refined flour samples was investigated using two extraction procedures, namely, ultrasonic (UAE) and microwave (MAE). The total phenolic acid (TPA) quantity in wheat bran (2711-2913μg/g) was significantly higher than the whole (664-715μg/g) and refined wheat (109-112μg/g) flour samples by both extraction methods as analyzed by liquid chromatography mass spectrometry. The recovery of phenolic acids from the spiked wheat bran sample was higher than from either the whole or refined wheat flour samples by both extraction procedures. The recovery of TPA (74-89%) from whole and refined wheat flours by MAE was significantly lower than that of UAE (90-98%). This difference was attributed to the gelatinization of starch present in the wheat flours caused by MAE. Gelatinization reduces the extractability of phenolic acids from wheat flour samples. Furthermore, both spectrometric assays (total phenolic content and radical scavenging capacities) showed similar trend as compared to LC-MS analyses.
authors.affiliation: Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, United States.
authors.forename: Yingjian
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, MD 20705, United States. Electronic address: Dave.Luthria@ars.usda.gov.
authors.forename: Devanand
authors.initials: D
authors.lastname: Luthria
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D005433:Flour / Q000032:analysis; D062385:Hydroxybenzoates / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods*; D010636:Phenols / Q000032:analysis*; D014908:Triticum / Q000737:chemistry*
chemical_list: D062385:Hydroxybenzoates; D010636:Phenols; C017616:phenolic acid
keywords: Gelatinization; LC–MS analysis; Microwave and ultrasonic-assisted extractions; Refined and whole wheat fractions; Total phenolic content and radical scavenging capacity