Douchi is a fermented food,which has a unique flavor after natural fermentation.However,the correlation between the microbial community and volatile flavor compounds is poorly studied.This study used MiSeq sequencing ...Douchi is a fermented food,which has a unique flavor after natural fermentation.However,the correlation between the microbial community and volatile flavor compounds is poorly studied.This study used MiSeq sequencing and headspace solid-phase microextraction-gas chromatography-mass spectrometry techniques to detect the dynamic changes of microbial succession and volatile compounds during fermented douchi and spearman correlation analysis.The results revealed that a total of 33 key flavor compounds were identified,among which the esters contributing to fruity and floral aromas were the main ones.The dominant strains included Bacillus spp.,Millerozyma spp.,and Aspergillus spp.Further analysis showed that in the post-fermentation stage,various yeast species were highly positively correlated with key flavor compounds such as 2-ethyl-methylbutanoate(fruity)and phenylacetaldehyde(floral).Furthermore,Aspergillus spp.Showed a positive correlation with 1-octen-3-one(mushroom).This study provides new insights into the analysis of microbial community succession and the characteristic flavor of Yangjiang douchi,which also offers valuable guidance for quality control and the subsequent screening of potential new starter cultures.展开更多
In the paper,an optical fiber sensor based on a seven-core fiber composite structure is presented,which enables dual-parameter sensing of bending and temperature.The proposed structure is fabricated by combining the s...In the paper,an optical fiber sensor based on a seven-core fiber composite structure is presented,which enables dual-parameter sensing of bending and temperature.The proposed structure is fabricated by combining the strongly-coupled seven-core fibers(SC-SCFs)and a weakly-coupled seven-core fiber(WC-SCF).The SC-SCF acts as a beam coupler and enhances the Mach-Zehnder interference,while the WC-SCF serves as the enhanced section of another Mach-Zehnder interference.Therefore,the spectrum response of the fiber structure mentioned above exhibits a superposition effect of two Mach-Zehnder interferometers(MZIs).Among them,two dips corresponding to different MZIs are used to measure bending and temperature.The experimental results show the bending sensitivity and temperature sensitivity of the two MZIs are-4.238 nm/m^(-1),-2.263 nm/m^(-1),0.047 nm/℃,and 0.064 nm/,respectively.It proves℃that our sensor is very sensitive to bending.Through the dual-wavelength matrix method,the bending and temperature can be measured simultaneously.With the benefit of the composite structure,low cost,and ease of fabrication,the proposed sensor can be used in harsh environments.展开更多
基金supported by the 2022 Guangdong Province science and technology innovation special Fund(SDZX2022030)research Project on the Development of Core Flavouring ingredients and Quality Enhancement of a range of sauces based on Mei Wei Yuan’s PhD Workstation(330601062212)the scientific research start-up Funds of Guangdong ocean University(360302062402).
文摘Douchi is a fermented food,which has a unique flavor after natural fermentation.However,the correlation between the microbial community and volatile flavor compounds is poorly studied.This study used MiSeq sequencing and headspace solid-phase microextraction-gas chromatography-mass spectrometry techniques to detect the dynamic changes of microbial succession and volatile compounds during fermented douchi and spearman correlation analysis.The results revealed that a total of 33 key flavor compounds were identified,among which the esters contributing to fruity and floral aromas were the main ones.The dominant strains included Bacillus spp.,Millerozyma spp.,and Aspergillus spp.Further analysis showed that in the post-fermentation stage,various yeast species were highly positively correlated with key flavor compounds such as 2-ethyl-methylbutanoate(fruity)and phenylacetaldehyde(floral).Furthermore,Aspergillus spp.Showed a positive correlation with 1-octen-3-one(mushroom).This study provides new insights into the analysis of microbial community succession and the characteristic flavor of Yangjiang douchi,which also offers valuable guidance for quality control and the subsequent screening of potential new starter cultures.
基金supported by“Pioneer”and“Leading Goose”Research&Development Program of Zhejiang,China(Grant No.2022C03084)the Natural Science Foundation of China(Grant No.62205296)+1 种基金the Zhejiang Provincial Natural Science Foundation of China(Grant Nos.LQ22F050007 and LQ23F050004)the Ningbo Science and Technology Project,China(Grant No.2021Z030).
文摘In the paper,an optical fiber sensor based on a seven-core fiber composite structure is presented,which enables dual-parameter sensing of bending and temperature.The proposed structure is fabricated by combining the strongly-coupled seven-core fibers(SC-SCFs)and a weakly-coupled seven-core fiber(WC-SCF).The SC-SCF acts as a beam coupler and enhances the Mach-Zehnder interference,while the WC-SCF serves as the enhanced section of another Mach-Zehnder interference.Therefore,the spectrum response of the fiber structure mentioned above exhibits a superposition effect of two Mach-Zehnder interferometers(MZIs).Among them,two dips corresponding to different MZIs are used to measure bending and temperature.The experimental results show the bending sensitivity and temperature sensitivity of the two MZIs are-4.238 nm/m^(-1),-2.263 nm/m^(-1),0.047 nm/℃,and 0.064 nm/,respectively.It proves℃that our sensor is very sensitive to bending.Through the dual-wavelength matrix method,the bending and temperature can be measured simultaneously.With the benefit of the composite structure,low cost,and ease of fabrication,the proposed sensor can be used in harsh environments.
