## 2 Materials and Methods
### Statistical Analysis  
Analyses of variance (ANOVAs) were run on the sensory descriptive data using SAS ver.6.12 (SAS Institute, Cary, NC, USA) by employing a three-way mixed model (judges, samples, and replications), with all two-way interactions with judges treated as random. Individual product differences were identified by [PERSON]'s least significant difference (LSD) test. The mean intensities of 22 significantly different sensory attributes were used to perform principal component analysis (PCA) using the covariance matrix with no rotation on XLSTAT ver. 2022.1 (Addinsoft, New York, NY, USA). PCA was also performed on the mean concentrations of 56 volatiles detected in more than 6 samples using the correlation matrix. These volatiles were significantly different among samples by two-way ANOVA (sample, duplicate injections). To evaluate any relationships among the chemical, volatile, and sensory data, multiple factor analysis (MFA) was conducted with XLSTAT using 4 chemical compositions, 22 sensory attributes, and 56 volatile compounds.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Attribute** & **Code** & **Written Definition** & **Physical Standards** \\ \hline _Aroma_ & & & \\ Alcohol & Alcohol\_A & Alcohol aroma & 25\% (\(w/v\)) ethanol \\ Sour\_Aroma & Sour\_A & Sour aroma & Acetic acid 2 mL/_distilled_ water 100 mL \\ Sweet\_Aroma & Sweet\_A & Sweet aroma (e.g., honey/syrup) & Honey 20 mL/white sugar 20 g/_distilled_ water 100 mL \\ Green Grape & Grape\_A & Green grape aroma & Crushed green grape 30 g \\ Tree Fruit & Treefru\_A & Tree fruit (e.g., pear/apple) & Apple juice, crushed Korean pear juice \\ Pineapple & Pineap\_A & Pineapple aroma & Pineapple fruit bowl \\ Barley & Barley\_A & Grain aroma (e.g., _nurungii_) & A typical barely drink \\ Yeast & Yeast\_A & Activated yeast aroma (e.g., _Makgelli_) & Yeast 0.1\% in 10% warm sugar solution \\ Earthy & Earthy\_A & Wet basement, earthy aroma & Soil 30 g/_distilled_ water 70 g \\ Soy Sauce & Soy\_A & Soy sauce aroma (e.g., traditional Korean soy sauce) & Traditional Korean soy sauce 30 mL \\ Woody & Woody\_A & Brandy aroma (e.g., wood, straw, fallen leaves) & 70 mL brandy/30 mL distilled water \\ Metal & Metal\_A & Metallic aroma & Stainless-steel sponge 30 g/tap water 20 g \\ Bleach & Bleach\_A & Bleach aroma in hydrogen peroxide/100 mL \\ _Flavor/Taste_ & & & distilled water \\ Bitter & Bitter & Bitter & Caffeic acid 0.1\% (\(w/v\)) \\ Sour & Sour & Sour & Acetic acid 0.1\% (\(w/v\)) \\ Salty & Salty & Salty & Salt 2 g/100 mL distilled water \\ Sweet & Sweet & Sweet & White sugar 20 g/distilled water 100 mL \\ Alcohol Flavor & Alcohol & Alcohol flavor & 25\% (\(w/v\)) ethanol \\ Fruit\_Flavor & Fruity & Overall fruity flavor & Green grape 30 g, pineapple fruit bowl \\ Mint\_Flavor & Mint flavor (e.g., Listerine) & Listerine 20 mL/distilled water 100 mL \\ Barley\_Flavor & Barley & Savory flavor of grain & A typical barely drink \\ Earthy\_Flavor & Earthy & Wet basement, earthy flavor & Soil 30 g/distilled water 70 g \\ Metal\_Flavor & Metallic & Metallic flavor (e.g., iron, corroded iron) & Stainless-steel sponge 30 g/tap water 20 g \\ _Texture/Mouthfeel_ & & & \\ Astringent & Astrin & Mouthfeel of dryness & Aluminum sulfate 0.1\% (\(w/v\)) \\ Cooling Sensation & Cooling & Cool feeling & Peppermit candy 30 g \\ Spicy & Spicy & Feeling of stinging taste & Mustard flour 30 g in distilled water \\  & & & 15 mL \\ Swallow & Soft & Smooth swallowing from mouth to & No physical standards \\  & & esophagus & No physical standards \\ Body & Body & Thickness or pressure of drinks on & No physical standards \\  & tongue, strong full mouthfeel & & \\ \hline \hline \end{tabular}
\end{table}
Table 2: Sensory codes, attributes, definitions, and physical standards of distilled _Soju_.