Dataset on the total phenolic contents and total anti-oxidants capacity in commercially available whiskey

Data in this article are acquired from 46 naturally distilled whiskey. Whiskey samples were produced in the United Kingdom, United States, Ireland, Scotland, and Canada. Samples differ with their type of distillery including (Blended, finest blended, Malted, single Malted, rye, straight Rye, special blended, and special reserved), years of aging, and ethanol percentages. The contents of beneficial bioactive components including total phenolic contents and total anti-oxidants activity and the correlation between them were addressed.


Specifications
Food science Specific subject area Total phenolic content and total anti-oxidant capacity in aged Whiskey Type of data

Value of the Data
• These data can add an additional information regarding the content of total phenolic content and anti-oxidant capacity of 46 common whisky commodity • This dataset is necessary as a qualification approach to the systematic identification of whiskey products • The method of determination of total anti-oxidants capacity described in this manuscript is precise, relevant, and short time consuming that can be used by oenologists and whiskey researchers

Data Description
This dataset contains analyzed data obtained by galvanostatic coulometric analyzer and spectrophotometer from freshly opened whiskey bottles obtained from the supermarket. Whiskey samples were produced in the United Kingdom, United States, Ireland, Scotland, and Canada. Samples differ with their type of distillery including (Blended, finest blended, Malted, single Malted, rye, straight Rye, special blended, and special reserved), years of aging, and ethanol percentages. Dataset provided about total phenolics content and total anti-oxidants capacity is displayed in Table 1 . Data on years of distillation was obtained from the labelling of each bottle. Correlations between total phenolic contents, total anti-oxidants capacity, and distillation years are shown in Table 2 . 19.23 ± 0.14 * no-age-statement whisky Table 2 Correlations between total phenolic contents, total anti-oxidants capacity, and distillation years.

Total phenols content
This method is based on the oxidation of phenolic compounds with a Folin-Chocalteu reagent. The reagent is a mixture of phosphoric-tungsten H3PW12O40 and phosphoricmolybdenum H3PMo12O40 acids, which are reduced by oxidation due to the existence of phenols into a mixture of oxides including blue tungsten (W8O23) and molybdenum (MO8O23). Blue staining makes it possible to measure the maximum absorption of the solution. It is proportional to the content of phenolic compounds.
Sample preparation comprises the preparation of a reaction mixture including 30 ml of whiskey, 2220 mL distilled water, 150 mL of Folin-Chocalteu reagent, 600 ml of a 20% solution of sodium carbonate (Na2CO3).
A control sample was also prepared, where distilled water was used instead of whiskey. Thus, the composition of the control sample was as follows: 2250 μl distilled water, 150 μl of Folin-Chocalteu reagent, 600 μl of a 20% solution of sodium carbonate (Na2CO3).
Further, the obtained solutions were kept for 90 min at room conditions until the complete completion of the oxidation reaction of phenolic compounds, when the optical density practically did not change during subsequent measurements, which made it possible to reduce the error several times.
Optical density measurements were carried out at a wavelength of 750 nm using (Shimadzu UV 2401pc, Japan) spectrophotometer. Measurements were carried out in 1 cm thick cuvettes. Total phenolic content was expressed as mg gallic acid equivalents (GAE) per milliliter of Whiskey using gallic acid calibration curve (R2 = 0.989). For this purpose, a calibration graph was constructed. The average value of triplicate measurements for each sample was used for calculation.

Total anti-oxidant capacity
The principle of determination of AOC in whiskey samples is based on Faraday's law where the mass of the analyte is determined by the amount of electricity spent on the reaction. The method was described by Lapin A. and Othman A.J. [ 2 , 3 ] and slightly modified as the following: Exactly 1 mL of whiskey sample was transferred into the electrochemical cell containing 50 mL of buffer solution (0.2 M potassium bromide and 0.1 M sulfuric dioxide) with continuous stirring for 1 min. The electrolysis process begins when electric current generates Bromine anions at a constant current of 50 mA from the buffer solution.
The electrolysis begins at 40 millivolts, the initial, and the end value of the electrical titration were adjusted on 150 millivolts.
The initial and end values of electro-titration were set on 200 mV electrical current. Bromine anions were generated under 50 mA electrical current where all compounds with anti-Oxidants properties would react with the excessive bromine anions. The electrolysis process initiated at 40 mV. Total anti-oxidants capacity expressed as mg ascorbic acid equivalents per 100 mL of whiskey.

Statistical Analysis
Pearson's correlation coefficient, means, and standard deviations were performed using SPSS 25