Measurement of antioxidants in distilled spirits by a silver nanoparticle assay

Abstract

Ingestion of antioxidants from the diet is associated with improved health. Total antioxidant capacity as gallic acid equivalents (GAE) of distilled spirits was determined using a modified and validated silver nanoparticle (SNaP) assay utilizing silver nanoparticles pre‐capped with starch and microwave technology. GAE concentrations determined by the SNaP assay for the distilled spirits were validated by high‐performance liquid chromatography (HPLC) measurements of key antioxidant components including gallic acid, ellagic acid, caffeic acid, syringic acid, syringaldehyde and 2‐furaldehyde. SNaP assay and HPLC measurements of GAE were compared via statistical and graphical methods to demonstrate comparability. Application of the assay to 33 different distilled spirits demonstrated good agreement with published literature values, with the highest total antioxidant capacity values observed for bourbon samples followed by whisky, tequila and other types of liqueur. This study is novel for demonstrating the utility of a nanoparticle assay for determination of antioxidant capacity in distilled spirits with validation by HPLC. © 2018 The Institute of Brewing & Distilling

Electroanalysis of Gallic and Ellagic Acids at a Boron‐doped Diamond Electrode Coupled with High‐performance Liquid Chromatography

“…% RSD values of 1.4-3.19 % and 1.31-2.85 % for the peak areas of GA and EA, respectively, in the whiskeys (n = 3) indicate high reliability in the concentrations of the acids determined. Concentrations of 1-35 μM and 8-99 μM of GA and EA, respectively, are reported in unidentified Scotch whiskeys [27]. EA was also identified as the predominant phenolic constituent in both singlemalt Scotch (~33 μM) and blended Scotch (~17 μM) [28] whiskey.…”

Characterisation of single malt Scotch Whisky using low powered ultrasound and UV‐Visible spectroscopy

“…This work found that new make spirit had no antioxidant activity so maturation was entirely responsible for the production/extraction of the antioxidant/phenolic compounds ( 56 ) . In 2018, the total antioxidant capacity of distilled spirits was determined using synthesised silver nanoparticles, however this sample set only included four Scotch Whiskies ( 57 ) .…”