Rapid Discrimination and Quality Assessment of Chinese Baijiu Flavor Profiles using SICRIT-MS Analysis

Rapid Discrimination and Quality Assessment of Chinese Baijiu Flavor Profiles using SICRIT-MS Analysis

Xiaokun Duan, Charles C. Liu
ASPEC Technologies Ltd., Beijing, CHINA.

First presented: ASMS, Baltimore USA. June 2025

Overview

To establish a rapid and high-throughput method for discriminating Chinese Baijiu flavor types and assessing quality using Soft Ionization by Chemical Reaction in Transfer (SICRIT) coupled with time-of-flight mass spectrometry (TOF-MS). This study focused on two primary aroma types—sauce aroma and strong aroma—by analyzing their volatile and semi-volatile compounds. The samples were analyzed directly without pretreatment, and the acquired spectral data were processed through principal component analysis (PCA) and Volcano plots. Distinct chemical profiles were observed between aroma types and even within samples of the same type with varying blending ratios, demonstrating the method’s capability for precise flavor differentiation and quality evaluation.

Introduction

Chinese Baijiu, a traditional distilled liquor, is characterized by diverse fermentation processes that yield approximately 12 distinct flavor types. These flavors are traditionally classified based on sensory evaluation, which is subjective and time-consuming. Advanced analytical techniques are required to objectively profile volatile compounds and ensure quality consistency, especially given the growing global demand and trade of Baijiu. In this study, SICRIT-MS, a soft ionization technique enabling real-time analysis of complex mixtures, was employed to rapidly differentiate sauce and strong aroma types. By analyzing hundreds of volatile species, including alcohols, aldehydes, and esters, this method provides a robust alternative to conventional approaches. The integration of PCA and statistical tools further enhances classification accuracy, offering a scientific foundation for quality control and authenticity verification in Baijiu production.

Material and Methods

I. Six Baijiu samples (three sauce aroma and three strong aroma) were collected in glass vials and analyzed without pretreatment. Volatile compounds were ionized using a SICRIT source (Plasmion, Germany) coupled to an Agilent 6530 QTOF mass spectrometer.
II. The SICRIT source was operated at 1500 V and 15 kHz frequency. Mass spectrometry was performed in positive ion mode with a scan range of m/z 40 – 2000, focusing on m/z 40 – 600 for enhanced volatile compound detection.
III. Data acquisition and processing were conducted using AnalyzerPro® XD software. Principal component analysis (PCA) and Volcano plots were generated to differentiate flavor types and identify marker ions. Tentative compound identification was based on accurate mass, isotope ratios, and library matching.

Results

Conclusions

A SICRIT-MS based method for rapid discrimination and quality assessment of Chinese Baijiu flavor profiles was successfully developed. The method requires no sample pretreatment and enables real-time analysis of volatile compounds, significantly reducing analysis time. PCA analysis could clearly identity the sauce and strong aroma types. Future improvements could expand the compound library for broader flavor coverage and integrate machine learning for automated classification. This approach serves as an efficient complement to traditional sensory evaluation, ensuring consistency and authenticity in Baijiu production.