{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T03:35:31Z","timestamp":1789011331691,"version":"build-2803163510"},"reference-count":44,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T00:00:00Z","timestamp":1787097600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32502152"],"award-info":[{"award-number":["32502152"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32172340"],"award-info":[{"award-number":["32172340"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32472480"],"award-info":[{"award-number":["32472480"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["32502152"],"award-info":[{"award-number":["32502152"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["32172340"],"award-info":[{"award-number":["32172340"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["32472480"],"award-info":[{"award-number":["32472480"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Young Elite Scientists Sponsorship Program by CAST","award":["2022QNRC001"],"award-info":[{"award-number":["2022QNRC001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>Empty cup aroma is a distinctive quality attribute of soy sauce aroma type baijiu (SSB), but the compounds responsible for its long persistence and their changes over time are still not well understood. Previous studies have mainly focused on key empty cup odourants at single time points. In this study, a typical commercial SSB was selected and monitored for 30 days using aroma extract dilution analysis (AEDA), time-resolved odour monitoring, residue peak area analysis and correlation with boiling point. AEDA revealed 65 aroma-active regions, including 63 in SSB, 36 in the empty cup and 34 shared by both. After emptying, the flavour dilution profile changed markedly: fruity esters and volatile aldehydes became less prominent, whereas sotolon showed the highest FD factor in the empty cup (FD 2048), and several acids and pyrazines also became prominent. The number of detectable regions increased from 43 at 0 h to 49 at 6 h, and then gradually decreased to 14 at day 30. Persistence was strongly correlated with boiling point (Spearman\u2019s \u03c1 = 0.7465, p &lt; 0.0001, n = 32). Peak area profiles also showed two general patterns. Low-boiling esters, aldehydes and dimethyl trisulfide decreased rapidly, whereas organic acids, pyrazines, phenylethyl alcohol, \u03b3-nonanolactone and ethyl hexadecanoate showed delayed maxima or non-monotonic changes. These results suggest that persistent empty cup aroma is not simply a residual form of the original baijiu aroma but develops through selective retention and temporal shifts in the contribution of different odourants.<\/jats:p>","DOI":"10.3390\/foods15162906","type":"journal-article","created":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T13:14:01Z","timestamp":1787145241000},"page":"2906","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Time-Resolved Profiling of Aroma-Active Compounds During the Persistence of Empty Cup Aroma in Soy Sauce Aroma Type Baijiu"],"prefix":"10.3390","volume":"15","author":[{"given":"Dan","family":"Qin","sequence":"first","affiliation":[{"name":"Food Laboratory of Zhongyuan, China Agricultural University, Beijing 100193, China"},{"name":"Key Laboratory of Geriatric Nutrition and Health, Ministry of Education, Beijing Technology and Business University, Beijing 100048, China"},{"name":"Department of Flavor Chemistry (150h), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstra\u00dfe 12, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiangrong","family":"Fan","sequence":"additional","affiliation":[{"name":"Food Laboratory of Zhongyuan, China Agricultural University, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-8396-8116","authenticated-orcid":false,"given":"Jiawen","family":"Duan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Geriatric Nutrition and Health, Ministry of Education, Beijing Technology and Business University, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lin","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Flavor Chemistry (150h), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstra\u00dfe 12, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiaqi","family":"Liang","sequence":"additional","affiliation":[{"name":"Department of Flavor Chemistry (150h), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstra\u00dfe 12, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingcheng","family":"Liu","sequence":"additional","affiliation":[{"name":"School of China Alcoholic Drinks, Luzhou Vocational and Technical College, Luzhou 646000, China"},{"name":"University-Enterprise Joint Innovation Base for Applied Brewing Engineering Technology of Sichuan Provincial Education Department, Luzhou 646000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanyan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Flavor Chemistry (150h), Institute of Food Science and Biotechnology, University of Hohenheim, Fruwirthstra\u00dfe 12, 70599 Stuttgart, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaoxue","family":"Chen","sequence":"additional","affiliation":[{"name":"Food Laboratory of Zhongyuan, China Agricultural University, Beijing 100193, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5568-3975","authenticated-orcid":false,"given":"Hehe","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Geriatric Nutrition and Health, Ministry of Education, Beijing Technology and Business University, Beijing 100048, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5425","DOI":"10.1021\/acs.jafc.8b00692","article-title":"Effect of fermentation processing on the flavor of Baijiu","volume":"66","author":"Liu","year":"2018","journal-title":"J. Agric. Food Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"104376","DOI":"10.1016\/j.tifs.2024.104376","article-title":"Unraveling the aroma profiling of Baijiu: Sensory characteristics of aroma compounds, analytical approaches, key odor-active compounds in different Baijiu, and their synthesis mechanisms","volume":"146","author":"Wang","year":"2024","journal-title":"Trends Food Sci. Technol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"149876","DOI":"10.1016\/j.foodchem.2026.149876","article-title":"Unraveling the fruity aroma in soy sauce aroma Baijiu by pinpointing key aroma compounds and evaluating their sensory impact","volume":"522","author":"Li","year":"2026","journal-title":"Food Chem."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"106696","DOI":"10.1016\/j.jfca.2024.106696","article-title":"Differences in flavor characteristics of rounds of Sauce-based Baijiu based on GC-IMS, GC-MS, and electronic tongue","volume":"135","author":"Lin","year":"2024","journal-title":"J. Food Compos. Anal."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"119742","DOI":"10.1016\/j.foodres.2026.119742","article-title":"Uncovering the flavor characteristics of soy sauce aroma baijiu from two important regions via multiple analytical approaches","volume":"241","author":"Mei","year":"2026","journal-title":"Food Res. Int."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"4614330","DOI":"10.1155\/2022\/4614330","article-title":"Insights into the aroma profile of sauce-flavor Baijiu by GC-IMS combined with multivariate statistical analysis","volume":"2022","author":"Cai","year":"2022","journal-title":"J. Anal. Methods Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"112735","DOI":"10.1016\/j.lwt.2021.112735","article-title":"Why the key aroma compound of soy sauce aroma type baijiu has not been revealed yet?","volume":"154","author":"Duan","year":"2022","journal-title":"LWT-Food Sci. Technol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"105147","DOI":"10.1016\/j.jfca.2023.105147","article-title":"Characterization of empty cup aroma in soy sauce aroma type Baijiu by vacuum assisted sorbent extraction","volume":"117","author":"Qin","year":"2023","journal-title":"J. Food Compos. Anal."},{"key":"ref_9","first-page":"93","article-title":"Lingering aroma composition in empty glass of sauce-flavor Baijiu by SHS-GC\/MS","volume":"40","author":"Sun","year":"2021","journal-title":"China Brew."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"137466","DOI":"10.1016\/j.foodchem.2023.137466","article-title":"Decoding the key compounds responsible for the empty cup aroma of soy sauce aroma type baijiu","volume":"434","author":"Qin","year":"2024","journal-title":"Food Chem."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"16955","DOI":"10.1021\/acs.jafc.4c01709","article-title":"Flavor perception and formation mechanism of empty cup aroma in soy sauce aroma type Baijiu","volume":"72","author":"Qin","year":"2024","journal-title":"J. Agric. Food Chem."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"137932","DOI":"10.1016\/j.foodchem.2023.137932","article-title":"Using in situ untargeted flavoromics analysis to unravel the empty cup aroma of Jiangxiang-type Baijiu: A novel strategy for geographical origin traceability","volume":"438","author":"Zhang","year":"2024","journal-title":"Food Chem."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"116481","DOI":"10.1016\/j.foodres.2025.116481","article-title":"Effects of lactic acid on the perception of volatile pyrazine aroma substances in Laimao Baijiu and its molecular interaction mechanisms","volume":"211","author":"Xiao","year":"2025","journal-title":"Food Res. Int."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"133765","DOI":"10.1016\/j.foodchem.2022.133765","article-title":"Research on interaction regularities and mechanisms between lactic acid and aroma compounds of Baijiu","volume":"397","author":"Zhang","year":"2022","journal-title":"Food Chem."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"147787","DOI":"10.1016\/j.foodchem.2025.147787","article-title":"Lactic acid modulates empty-cup aroma persistence in Baijiu via molecular interaction mechanisms: A case study of strong-aroma and soy-sauce-aroma Baijiu","volume":"503","author":"Liu","year":"2026","journal-title":"Food Chem."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"103396","DOI":"10.1016\/j.fochx.2025.103396","article-title":"Variation of aroma compounds in soy sauce aroma type baijiu during aging: Focusing on the regulatory effect of ethyl lactate on aroma release","volume":"33","author":"Zhao","year":"2026","journal-title":"Food Chem. X"},{"key":"ref_17","first-page":"141","article-title":"Release process of typical esters in Baijiu after forming empty cup aroma","volume":"43","author":"Zhao","year":"2024","journal-title":"China Brew."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1002\/(SICI)1520-667X(1999)11:10<737::AID-MCS7>3.0.CO;2-4","article-title":"Stir bar sorptive extraction (SBSE), a novel extraction technique for aqueous samples: Theory and principles","volume":"11","author":"Baltussen","year":"1999","journal-title":"J. Microcolumn Sep."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1771","DOI":"10.1007\/s12161-014-0060-z","article-title":"Use of stir bar sorptive extraction and thermal desorption for gas chromatography-mass spectrometry characterization of selected volatile compounds in Chinese liquors","volume":"8","author":"Niu","year":"2015","journal-title":"Food Anal. Methods"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Wang, L., Gao, M., Liu, Z., Chen, S., and Xu, Y. (2020). Three extraction methods in combination with GC\u00d7GC-TOFMS for the detailed investigation of volatiles in Chinese herbaceous aroma-type Baijiu. Molecules, 25.","DOI":"10.3390\/molecules25194429"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1187","DOI":"10.1002\/jsfa.4294","article-title":"Quantification of volatile compounds in Chinese soy sauce aroma type liquor by stir bar sorptive extraction and gas chromatography\u2013mass spectrometry","volume":"91","author":"Fan","year":"2011","journal-title":"J. Sci. Food Agric."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"109011","DOI":"10.1016\/j.jfca.2026.109011","article-title":"Characterization of key aroma compounds in four algae species using sensomics approach","volume":"152","author":"Xiang","year":"2026","journal-title":"J. Food Compos. Anal."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"106607","DOI":"10.1016\/j.jfca.2024.106607","article-title":"Analysis of aroma compounds in different grades of Luzhou Laojiao strong-aroma Baijiu by molecular sensory science","volume":"135","author":"Chen","year":"2024","journal-title":"J. Food Compos. Anal."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"107997","DOI":"10.1016\/j.jfca.2025.107997","article-title":"Aroma comparison of Qingke baijiu and other light-aroma baijiu produced with Daqu using molecular sensory science","volume":"147","author":"Gao","year":"2025","journal-title":"J. Food Compos. Anal."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"224","DOI":"10.1002\/jib.614","article-title":"Sesame flavour baijiu: A review","volume":"126","author":"Zhang","year":"2020","journal-title":"J. Inst. Brew."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Wu, J., Chen, R., Li, X., Fu, Z., Xian, C., Zhao, W., Zhao, C., and Wu, X. (2023). Comprehensive identification of key compounds in different quality grades of soy sauce-aroma type baijiu by HS-SPME-GC-MS coupled with electronic nose. Front. Nutr., 10.","DOI":"10.3389\/fnut.2023.1132527"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Yan, Y., Chen, S., Nie, Y., and Xu, Y. (2021). Quantitative analysis of pyrazines and their perceptual interactions in soy sauce aroma type Baijiu. Foods, 10.","DOI":"10.3390\/foods10020441"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"118705","DOI":"10.1016\/j.lwt.2025.118705","article-title":"Uncovering the key volatile compounds affecting the roasted aroma in sauce-flavor baijiu and their perceptual interactions","volume":"237","author":"Niu","year":"2025","journal-title":"LWT-Food Sci. Technol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1007\/s12078-017-9238-2","article-title":"Effects of ethanol on flavor perception in alcoholic beverages","volume":"10","author":"Ickes","year":"2017","journal-title":"Chemosens. Percept."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1724","DOI":"10.1016\/j.matt.2024.03.017","article-title":"Ethanol-water clusters determine the critical concentration of alcoholic beverages","volume":"7","author":"Yang","year":"2024","journal-title":"Matter"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"20855","DOI":"10.1038\/s41598-020-77697-5","article-title":"Understanding the lost functionality of ethanol in non-alcoholic beer using sensory evaluation, aroma release and molecular hydrodynamics","volume":"10","author":"Ramsey","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"9959","DOI":"10.1021\/jf3022892","article-title":"Effects of ethanol and long-chain ethyl ester concentrations on volatile partitioning in a Whisky model system","volume":"60","author":"Boothroyd","year":"2012","journal-title":"J. Agric. Food Chem."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Lu, J., Zheng, J., Zhao, D., Xu, Y., and Chen, S. (2025). The effect of ethanol on the compound thresholds and aroma perception in Chinese baijiu. Molecules, 30.","DOI":"10.3390\/molecules30040933"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"106071","DOI":"10.1016\/j.fbio.2025.106071","article-title":"Impact of organic acids on aroma release in light-flavor Baijiu: A focus on key aroma-active compounds","volume":"65","author":"Yuan","year":"2025","journal-title":"Food Biosci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"140883","DOI":"10.1016\/j.foodchem.2024.140883","article-title":"Evolution of self-assembled amphiphilic colloidal particles in strong-flavor Chinese baijiu","volume":"461","author":"Jiang","year":"2024","journal-title":"Food Chem."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"118060","DOI":"10.1016\/j.foodres.2025.118060","article-title":"Evolutionary pattern of liquid-liquid phase separation in amphiphilic molecular self-assembly during the natural aging process of strong-aroma Baijiu","volume":"225","author":"Jiang","year":"2026","journal-title":"Food Res. Int."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1016\/j.foodchem.2014.07.153","article-title":"Determination of sotolon content in South African white wines by two novel HPLC\u2013UV and UPLC\u2013MS methods","volume":"169","author":"Gabrielli","year":"2015","journal-title":"Food Chem."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1016\/j.fuel.2011.08.011","article-title":"Measurements of normal boiling points of fatty acid ethyl esters and triacylglycerols by thermogravimetric analysis","volume":"92","author":"Kieckbusch","year":"2012","journal-title":"Fuel"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"7569","DOI":"10.1021\/acs.jafc.6b02691","article-title":"Changes in wine ethanol content due to evaporation from wine glasses and implications for sensory analysis","volume":"64","author":"Wollan","year":"2016","journal-title":"J. Agric. Food Chem."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1016\/j.chroma.2007.01.032","article-title":"Stir bar sorptive extraction for trace analysis","volume":"1152","author":"David","year":"2007","journal-title":"J. Chromatogr. A"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"138487","DOI":"10.1016\/j.foodchem.2024.138487","article-title":"Characterization of key aroma compounds in soy sauce flavor baijiu by molecular sensory science combined with aroma active compounds reverse verification method","volume":"443","author":"Duan","year":"2024","journal-title":"Food Chem."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"108076","DOI":"10.1016\/j.jfca.2025.108076","article-title":"Aroma characterization and reconstitution of strong-aroma baijiu: Insights into sensory profiles and key odor-active compounds from Chinese core production areas","volume":"147","author":"Ma","year":"2025","journal-title":"J. Food Compos. Anal."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"102591","DOI":"10.1016\/j.fochx.2025.102591","article-title":"Characterization of Xiaoqu Qingxiangxing Baijiu by gas chromatography-olfactometry, quantitative measurements, aroma recombination, and omission experiments","volume":"28","author":"Li","year":"2025","journal-title":"Food Chem. X"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"1684","DOI":"10.1111\/1750-3841.16961","article-title":"Retronasal sensory characterization of aroma compounds in Baijiu by detection threshold measurement, retronasal OAVs, and time-intensity evaluation","volume":"89","author":"Yu","year":"2024","journal-title":"J. Food Sci."}],"container-title":["Foods"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2304-8158\/15\/16\/2906\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T13:32:40Z","timestamp":1787146360000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2304-8158\/15\/16\/2906"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,19]]},"references-count":44,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["foods15162906"],"URL":"https:\/\/doi.org\/10.3390\/foods15162906","relation":{},"ISSN":["2304-8158"],"issn-type":[{"value":"2304-8158","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,19]]}}}