Sensory and Volatile Profiles of Korean Commercially Distilled Soju Using Descriptive Analysis and HS-SPME-GC-MS

Abstract

Volatile compositions and sensory characteristics of 11 commercially distilled soju samples were investigated using headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) and sensory descriptive analysis. A total of 59 major volatile compounds, consisting of 32 esters, 10 alcohols, 2 acids, 5 aldehydes, 3 ketones, 1 hydrocarbon, 1 furan, 2 phenols, and 3 miscellaneous compounds, were identified. From the principal component analysis (PCA) of volatile data, MSJ made by atmospheric distillation showed a clear distinction in volatile compositions compared to that of other samples made by vacuum distillation. Based on PCA of the sensory data determined by a panel of ten judges, MSJ was associated with a large amount of longer chain esters that showed high intensities in bitter taste and yeast/nuruk-related flavor attributes. HYJ, LPJ, and HAJ made with rice as a raw material were associated with lower intensities of the alcohol aroma, while JRJ and OKJ aged in oak barrels were associated with fruit flavor, sweet flavor, and brandy aroma. In the partial least squares regression (PLSR) analysis to see any relationship between volatile and sensory data, longer chain esters like ethyl tetradecanoate, and ethyl hexadecanoate were highly associated with bleach aroma. In contrast, positive correlations were seen with barley aroma and yeast flavor with hexanal, nonanal, benzaldehyde, and 2-methoxy-phenol.

Effects of the proteins of indica rice and indica waxy rice on the formation of volatiles of sweet rice wine

“…Acid is an essential substance in alcoholic beverages, and organic acids in wine can be conducive to the balance of the flavour quality of wine (Tian et al ., 2021). A small amount of acid combined with alcohol will form esters (Hong et al ., 2020). For example, the acetic acid contents of indica waxy rice wine with IR‐Pro and IWR‐Pro as well as indica waxy rice wine were 6.37, 5.34 and 10.88 mg kg −1 , while their ethyl acetate contents were 6.51, 8.11 and 4.29 mg kg −1 respectively.…”

“…The level of 2,3-butanediol increased sharply after the addition of prolamin, and 50.36 mg kg −1 in IWRW with IR-Pro was almost seven times higher than that in IWRW without extra prolamin. In addition, β-phenylethyl alcohol was seen as a key aroma compound of Chinese rice wine according to the research of Xu et al (2021) and Japanese Shochu (Hong et al, 2020). Extra prolamin in rice wine fermentation improved β-phenylethyl alcohol generation, and the β-phenylethyl alcohol contents of rice wine with IR-Pro or IWR-Pro were 409.30 and 366.30 mg kg −1 , respectively, which were all significantly higher than that of IWRW at 250.49 mg kg −1 .…”

A sensory characterization of some N‐heterocycles in model spirit matrix: Influence of ethanol and several chemical features on aroma perception

“…It has been recently applied to evaluate Baiju and Soju spirits. 10,24 The free-comments method has gained popularity in the past decades both in wine and spirit evaluation. 25,26 Without a specific sensory methodology, the panellists are not restricted to a list of descriptors and are invited to relate whatever comes into their minds during the sensory session.…”

“…Moreover, this sensory methodology requires a minimum amount of training time before products can be actually evaluated. It has been recently applied to evaluate Baiju and Soju spirits 10,24 . The free‐comments method has gained popularity in the past decades both in wine and spirit evaluation 25,26 .…”

Comprehensive identification of key compounds in different quality grades of soy sauce-aroma type baijiu by HS-SPME-GC-MS coupled with electronic nose

“…The untargeted detection techniques have high sensitivity and a wide detection range ( 19 ), and the headspace solid-phase microextraction (HS-SPME) has the advantages of short extraction time and high sensitivity via various types of extraction materials ( 20 ). Hong et al ( 21 ) applied the untargeted techniques based on HS-SPME-GC-MS to analyze the volatile composition of soju and found significant differences in samples. Based on chemical components analysis, different samples can be analyzed with the help of multivariate statistical methods to find critical compounds.…”