Chemical Profiling and Bottle‐Aging Analysis of Sorghum Liquor Unveiled by Nuclear Magnetic Resonance Spectroscopy

ABSTRACT Bottle aging in alcoholic beverages contributes to their sensory evolution. Kinmen sorghum (“kaoliang”) liquor exhibits a pronounced bottle‐aging phenomenon, which is tied to its sensory qualities and market price. However, a rigorous scientific understanding and analysis of these bottle‐aging dynamics is still lacking. This study examines the chemical changes in Kinmen kaoliang liquors during bottle aging. We developed a robust method to suppress the ethanol signals in nuclear magnetic resonance spectroscopy, allowing us to obtain the chemical profiles of the liquors across different bottle aging periods and conduct chemometric and statistical analyses on these profiles. The distinct chemical profiles of different kaoliang liquors can be attributed to differences in production methods, which are correlated with their characteristics in taste. More importantly, for liquors produced through solid‐state fermentation, the effect of bottle aging was clearly demonstrated by analyzing the evolution of their chemical profiles over different periods of bottle aging. This research highlights the impact of production methods and aging on the composition of sorghum liquors. The presented workflow is easily scalable and provides a path for obtaining insights that could inform future production and maturation optimizations in an industrial setting.