Li Li,Cuixin Huang,Zhicheng Li,Yulin Zhao,Jun Liu,Yu Zheng,Rong Cao,Yuting Liao
Sichuan shai vinegar (SSV) is an acidic condiment with a long history and unique flavor. Aging is an important production process that determines the unique flavor of shai vinegar. This study compared the differences in physicochemical properties, volatile flavor, and non-volatile flavor substances between the constant temperature aging and natural aging methods of SSV Cupei . The results showed that the total acid and amino acid nitrogen content in naturally aged vinegar was higher than that in constant temperature aged vinegar. Furthermore, 20 different volatile flavor substances and 65 different non-volatile flavor substances were obtained after 21 and 25 days of constant temperature aging and 1, 3, and 5 years of natural aging SSV samples. This indicates that the temperature environment during natural aging was more moderate, allowing acidic compounds to form and stably exist in the aging environment. Correlation analysis further demonstrated that there were more differentiated non-volatile substances significantly related to the Maillard reaction under constant temperature aging condition and related to antioxidant activity under natural aging condition. The results of this study provide a comprehensive understanding of the characteristics and applications of the two aging methods of SSV and guide strategy for factories in the selection of aging methods.
Yi Lv,Feng-Lian Ma,Jia-Nan Wang,Yao Zhang,Yuan Jiang,Qian Ge,Yong-Jie Yu
The time involved and the high economic cost of using oak barrels to age wines have led to a significant price difference compared to non-oak barrel aged wines and may lead to some fraudulent sales in the market. In this study, an untargeted metabolomic strategy was developed to detect the metabolite composition of oak barrel aged and non-oak barrel aged wines in both positive and negative ion modes by using UHPLC–HRMS combined with the recently developed chemometric method AntDAS. The results of partial least squares discrimination analysis (PLS-DA) showed that the samples were characterized into two categories. Finally, 51 compounds were identified in positive ion mode, while 26 compounds were identified in negative ion mode. The results indicate that combining UHPLC–HRMS with AntDAS can reveal the material basis of wines and has excellent potential to differentiate between oak barrel aged and non-oak barrel aged wines.Keywords:oak barrel aged wines;UHPLC-HRMS;AntDAS;chemometrics
Zhenjiang aromatic vinegar is one of the most popular vinegars in China, which can be produced by either traditional or modern techniques. Aroma profiles of the traditional Zhenjiang aromatic vinegar (TZAV) and the modern Zhenjiang aromatic vinegar (MZAV) at different stages of their aging were analyzed by headspace solid-phase microextraction (HS-SPME) with an aid of DVB/CAR/PDMS fiber combined with gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). A total of 53 volatile compounds were identified. Among them, 43 aromas were positively identified after comparison with their corresponding authentic compounds. Two volatiles, including isopentyl alcohol and butyl benzoate, were only identified in TZAV, while propiophenone was only identified in MZAV. In addition, some volatiles were found to be generated during the aging period, which included isopentyl alcohol, 3-(methylthio)propyl acetate, and 2-acetoxy-3-butanone in the TZAV samples, and 2-ethyl-1-hexanol, octanoic acid, propiophenone, and dimethyl trisulfide in the MZAV samples. The total amount of volatile compounds in the MZAV was greater than its counterpart TZAV. Moreover, 29 odor-active compounds were recognized by GC-O analysis, while 25 of them were confirmed by their authentic compounds, and their perceived odors included sweet, acid, buttery, floral, herbal, fruit, fresh, pungent, almond, and geraniol notes.