Thyme ( Thymus vulgaris L. ) is widely used as a traditional spice in the cooking of goat meat (mutton) due to its distinctive flavor and the ability to weaken the “goaty flavor”. To investigate the aroma characteristics of stewed mutton with thyme (SMT), four SMT samples prepared using different cooking utensils were analyzed by gas chromatography–mass spectrometry/olfactometry (GC–MS/O). Totally, 26 aroma-active compounds (AACs) were determined by GC–MS/O and further quantified. Among these, 20 AACs exhibited odor activity values (OAV) greater than 1. However, no significant differences existed among the four SMTs, which indicated that different utensils had little effect on the aroma profile of SMTs. Aroma recombination and omission experiments results showed that nonanal, ( E )-2-octenal, and ( E,E )-2,4-decadienal had the greatest contribution to the aroma profile of SMTs. These three compounds, together with dimethyl trisulfide, 3-methyl-butanal, octanal, ( E )-2-decenal, ( E )-2-nonenal, methanethiol, hexanal, ( E )-2-undecenal, and 1-octen-3-ol, were confirmed as the key aroma compounds in SMTs.
Pseudomonas aeruginosa is a notoriously difficult pathogen to control with antibiotics and disinfectants. Thymus vulgaris L. essential oil (TEO) and thymol are useful for replacing synthetic bacteriostatic agents due to their broad-spectrum bactericidal properties. This study focuses on understanding the inhibitory effects of TEO and its major component against P. aeruginosa , and exploring the antibacterial mechanism from the perspectives of cell membrane destruction, DNA intercalation and biofilm prevention. Results indicate that thymol is the principal component in TEO, as confirmed by GC-MS analysis. TEO and thymol potently combat the planktonic P. aeruginosa and directly change the cell structure. P. aeruginosa cell membrane integrity is destroyed as evidenced by an increase in permeability of the inner and outer membranes and the leakage of intracellular biological macromolecules (DNA). Our study further confirms that the accumulation of intracellular ROS caused by TEO and thymol can result in oxidative stress-mediated DNA damage. Thymol intercalates in the P. aeruginosa genomic DNA to affect the normal function of DNA and even cause bacterial death. Moreover, TEO and thymol affect the biofilm formation and limit the bacterial swimming and swarming motilities. This study provides a potential approach for the development and utilization of natural essential oils and bioactive compunds as novel food additives in the food processing.
Tianle Wu,Peng Wang,Yuyu Zhang,Ping Zhan,Yu Zhao,Honglei Tian,Wanying He
Mutton possesses a typical flavor, known as “muttony” or “goaty”, which significantly limits consumers’ acceptability and its further popularization. Generally, this unpleasant flavor originates from mutton tallow. Thus, we first characterized the key volatiles of the cooked mutton tallow (CMT) via gas chromatography-mass spectrometry/olfactometry (GC–MS/O) and odor activity value (OAV). Combined with aroma recombination and omission tests, eleven compounds, involving 4-methyloctanoic acid, 4-methynonanoic acid, octanoic acid, decanoic acid, hexanal, heptanal, ( E )-2-octenal, ( E )-2-nonenal, ( E )-2-decenal, 2-nonanone and 2-penty-furan, were screened out to be responsible for the “muttony” flavor. The objective of this study was to investigate the sensory property and acceptability of CMTs, elaborated with 4 different levels of thyme phenolic extract (TPE), through descriptive sensory analysis and key muttony-related compounds identification. The results showed that, of different TPEs employed, CMT plus TPE3 was the most effective strategy to control the key “muttony” contributors, thereby to improve flavor profile of CMT.
危险品化学品经营许可证（带存储）