title: Aroma improvement by repeated freeze-thaw treatment during Tuber melanosporum fermentation.
abstract: The aroma attributes of sulfurous, mushroom and earthy are the most important characteristics of the aroma of Tuber melanosporum. However, these three aroma attributes are absent in the T. melanosporum fermentation system. To improve the quality of the aroma, repeated freeze-thaw treatment (RFTT) was adopted to affect the interplay of volatile organic compounds (VOCs). Using RFTT, not only was the score on the hedonic scale of the aroma increased from the "liked slightly" to the "liked moderately" grade, but the aroma attributes of sulfurous, mushroom and earthy could also be smelled in the T. melanosporum fermentation system for the first time. A total of 29 VOCs were identified, and 9 compounds were identified as the key discriminative volatiles affected by RFTT. Amino acid analysis revealed that methionine, valine, serine, phenylalanine, isoleucine and threonine were the key substrates associated with the biosynthesis of the 9 key discriminative VOCs. This study noted that amino acid metabolism played an important role in the regulation of the aroma of the T. melanosporum fermentation system.
authors.affiliation: Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Provincial Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068 China.
authors.forename: Deng-Rong
authors.initials: DR
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Provincial Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068 China.
authors.forename: Rui-Sang
authors.initials: RS
authors.lastname: Liu
authors.affiliation: Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Provincial Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068 China.
authors.forename: Long
authors.initials: L
authors.lastname: He
authors.affiliation: Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Provincial Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068 China.
authors.forename: Hong-Mei
authors.initials: HM
authors.lastname: Li
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 China.
authors.forename: Ya-Ling
authors.initials: YL
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 China.
authors.forename: Xin-Hua
authors.initials: XH
authors.lastname: Liang
authors.affiliation: Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 China.
authors.forename: Tao
authors.initials: T
authors.lastname: Chen
authors.affiliation: Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Provincial Key Laboratory of Industrial Microbiology, Hubei University of Technology, Wuhan 430068 China.
authors.forename: Ya-Jie
authors.initials: YJ
authors.lastname: Tang
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001203:Ascomycota / Q000378:metabolism*; D005285:Fermentation; D005615:Freezing; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D025341:Principal Component Analysis; D012903:Smell; D055549:Volatile Organic Compounds / Q000032:analysis
chemical_list: D000596:Amino Acids; D055549:Volatile Organic Compounds