E-jiao(Colla Corii Asini,CCA)has been widely used as a healthy food and Chinese medicine.Although authentic CCA is characterized by its typical sweet and neutral fragrance,its aroma components have been rarely investi...E-jiao(Colla Corii Asini,CCA)has been widely used as a healthy food and Chinese medicine.Although authentic CCA is characterized by its typical sweet and neutral fragrance,its aroma components have been rarely investigated.This work investigated the aroma-active components and antioxidant activity of 19 CCAs from different geographical origins.CCA extracts obtained by simultaneous distillation and extraction were analyzed by gas chromatography-mass spectrometry(GC-MS),gas chromatography-olfactometry(GC-O)and sensory analysis.The antioxidant activity of CCAs was determined by ABTS and DPPH assays.A total of 65 volatile compounds were identified and quantified by GC-MS and 23 aroma-active compounds were identified by GC-O and aroma extract dilution analysis.The most powerful aroma-active compounds were identified based on the flavor dilution factor and their contents were compared among the 19 CCAs.Principal component analysis of the 23 aroma-active components showed 3 significant clusters.Canonical correlation analysis between antioxidant assays and the 23 aroma-active compounds indicates strong correlation(r=0.9776,p=0.0281).Analysis of aroma-active components shows potential for quality evaluation and discrimination of CCAs from different geographical origins.展开更多
P omegranate(Punica granatum L.)has attracted considerable attention in world markets due to its valuable nutrients and highly appreciated sensory properties.The aroma profiles of 4 varieties of pomegranate juice,incl...P omegranate(Punica granatum L.)has attracted considerable attention in world markets due to its valuable nutrients and highly appreciated sensory properties.The aroma profiles of 4 varieties of pomegranate juice,including Dahongtian(DP),Jingpitian(JP),Luyudan(LP),and Tianhonngdan(TP),were investigated via gas chromatography-mass spectrometry(GC-MS)and gas chromatography-olfactometry(GC-O)analyses.A total of 43 volatile compounds were identified by using GC-MS.Among these compounds,16 were considered as potential aroma-active compounds as detected by GC-O.These compounds belonged to the classes of terpinenes,alcohols,and aldehydes.Eleven volatile compounds were defined as the main contributors to the overall aroma of pomegranate juice due to their high odor activity values(OAVs≥1).Aroma recombination and omission tests confirmed thatβ-myrcene,1-hexanol,and(Z)-3-hexen-1-ol were the key aroma compounds,and limonene,1-octen-3-ol,linalool,and hexanal were important aroma-active compounds in DP samples.展开更多
Flavor characteristics of raw shrimp,high-salt and low-salt shrimp paste were evaluated and compared by sensory analysis,headspace-gas chromatography-ion mobility spectrometry(HS-GC-IMS)and solid-phase microextraction...Flavor characteristics of raw shrimp,high-salt and low-salt shrimp paste were evaluated and compared by sensory analysis,headspace-gas chromatography-ion mobility spectrometry(HS-GC-IMS)and solid-phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS).In addition,aroma profiles and aroma-active compounds in these three samples were analyzed by solvent-assisted flavor evaporation-gas chromatography-olfactometry-mass spectrometry(SAFE-GC-O-MS).Results of sensory evaluation revealed that these three samples showed significant differences in sensitivity to the W2W,W2S,W1S and W1W sensors of the electronic nose(p<0.05),which represent organic sulfides,alkane aromatic compounds,short chain alkanes,and sulfides,respectively.Assessment of sensory parameters indicated tha high-salt shrimp paste had a strong roasted and meaty aroma,while low-salt shrimp paste showed an umami aroma more similar to raw shrimp.A total of 118 volatile compounds were identified using the three afore-mentioned gas chromatography methods.Among them,37 aroma-active compounds were detected by GC-O.High-salt shrimp was shown to contain more acids,aldehydes and heterocyclic compounds,which resembled cheese,roasted and meaty aromas.In contrast,low-salt shrimp paste contained more esters,which was similar to the umami aroma profile of raw shrimp.Interestingly,pyrazines were only produced in fermented shrimp paste samples,suggesting that they were produced during the fermentation process and they may contribute unique roasted and meaty aromas,which were important for the overall aroma characteristics of shrimp paste.展开更多
Due to the premium flavor,Qingxin oolong tea(QOT),which is grown and produced in Taiwan,is widely appreciated.Roasting is a crucial process for shaping its flavor.However,the effect of roasting on the aroma and taste ...Due to the premium flavor,Qingxin oolong tea(QOT),which is grown and produced in Taiwan,is widely appreciated.Roasting is a crucial process for shaping its flavor.However,the effect of roasting on the aroma and taste of QOT was not fully understood.In this study,the volatile composition,aroma-active compounds and phenolic profile of QOT with different roasting degrees,including the unroasted(UR),the medium roasted(MR)and the heavy roasted(HR)were analyzed.As revealed by headspace solid phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS)and multivariate statistical analyses,UR and MR demonstrated similar volatile profiles,while heavy roasting changed the volatile composition greatly.Multiple nitrogen-containing compounds,such as 3,5-diethyl-2-methylpyrazine and 2-ethyl-3,5-dimethylpyrazine,were uniquely found in heavy roasted samples,which can be ascribed to the extensive Maillard reaction.Moreover,eight compounds were identified and verified as key aroma-active compounds by using gas chromatography-olfactometry-mass spectrometry(GC-O-MS),aroma recombination and omission experiments.The aldehydes and alcohols,such as linalool,benzeneacetaldehyde andα-farnesene,with a floral scent were the dominant aroma-active compounds in UR and MR,while 2-ethyl-3,5-dimethylpyrazine and 3,5-diethyl-2-methylpyrazine with a roasted scent were the main aroma-active compounds in HR.Furthermore,as revealed by ultra-high performance liquid chromatography and Orbitrap high resolution mass spectrometry(UHPLC-Q-Orbitrap-MS),flavanols and phenolic acids were significantly lower in abundance in UR and MR as compared to those in HR,whereas flavonols were less affected by roasting.These findings provide useful information for understanding the flavor characteristics of this popular oolong tea for the first time.展开更多
基金Authors are grateful to the financial support from the National Natural Science Foundation of China(Grants Nos.21706233,21776321,21576297,21665022,21476270)Lu Xu is financially supported by Tongren Culture,Science and Technology Industry Innovation Research Center and the China Postdoctoral Science Project(No.2016M602719)+3 种基金Guizhou Engineering Research Center(QJHKYZ[2017]024)Students Innovation and Entrepreneurship Training Center of Food Science and Technology in Tongren University(No.2016SJDCZX001)the Open Research Program(Nos.2015ZD001,2015ZD002 and 2015ZY006)the Modernization Engineering Technology Research Center of Ethnic Minority Medicine of Hubei province(South-Central University for Nationalities).
文摘E-jiao(Colla Corii Asini,CCA)has been widely used as a healthy food and Chinese medicine.Although authentic CCA is characterized by its typical sweet and neutral fragrance,its aroma components have been rarely investigated.This work investigated the aroma-active components and antioxidant activity of 19 CCAs from different geographical origins.CCA extracts obtained by simultaneous distillation and extraction were analyzed by gas chromatography-mass spectrometry(GC-MS),gas chromatography-olfactometry(GC-O)and sensory analysis.The antioxidant activity of CCAs was determined by ABTS and DPPH assays.A total of 65 volatile compounds were identified and quantified by GC-MS and 23 aroma-active compounds were identified by GC-O and aroma extract dilution analysis.The most powerful aroma-active compounds were identified based on the flavor dilution factor and their contents were compared among the 19 CCAs.Principal component analysis of the 23 aroma-active components showed 3 significant clusters.Canonical correlation analysis between antioxidant assays and the 23 aroma-active compounds indicates strong correlation(r=0.9776,p=0.0281).Analysis of aroma-active components shows potential for quality evaluation and discrimination of CCAs from different geographical origins.
基金funded by Shaanxi Natural Science Foundation (2019JQ-665)Xi’an Agricultural Science and Technology Project (20NYYF0021)supported by the Open Project Program of Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University (BTBU), Beijing 100048, China (SPFW2020YB12)
文摘P omegranate(Punica granatum L.)has attracted considerable attention in world markets due to its valuable nutrients and highly appreciated sensory properties.The aroma profiles of 4 varieties of pomegranate juice,including Dahongtian(DP),Jingpitian(JP),Luyudan(LP),and Tianhonngdan(TP),were investigated via gas chromatography-mass spectrometry(GC-MS)and gas chromatography-olfactometry(GC-O)analyses.A total of 43 volatile compounds were identified by using GC-MS.Among these compounds,16 were considered as potential aroma-active compounds as detected by GC-O.These compounds belonged to the classes of terpinenes,alcohols,and aldehydes.Eleven volatile compounds were defined as the main contributors to the overall aroma of pomegranate juice due to their high odor activity values(OAVs≥1).Aroma recombination and omission tests confirmed thatβ-myrcene,1-hexanol,and(Z)-3-hexen-1-ol were the key aroma compounds,and limonene,1-octen-3-ol,linalool,and hexanal were important aroma-active compounds in DP samples.
基金supported by the National Natural Science Foundation of China[grant numbers 32072348,31671825].
文摘Flavor characteristics of raw shrimp,high-salt and low-salt shrimp paste were evaluated and compared by sensory analysis,headspace-gas chromatography-ion mobility spectrometry(HS-GC-IMS)and solid-phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS).In addition,aroma profiles and aroma-active compounds in these three samples were analyzed by solvent-assisted flavor evaporation-gas chromatography-olfactometry-mass spectrometry(SAFE-GC-O-MS).Results of sensory evaluation revealed that these three samples showed significant differences in sensitivity to the W2W,W2S,W1S and W1W sensors of the electronic nose(p<0.05),which represent organic sulfides,alkane aromatic compounds,short chain alkanes,and sulfides,respectively.Assessment of sensory parameters indicated tha high-salt shrimp paste had a strong roasted and meaty aroma,while low-salt shrimp paste showed an umami aroma more similar to raw shrimp.A total of 118 volatile compounds were identified using the three afore-mentioned gas chromatography methods.Among them,37 aroma-active compounds were detected by GC-O.High-salt shrimp was shown to contain more acids,aldehydes and heterocyclic compounds,which resembled cheese,roasted and meaty aromas.In contrast,low-salt shrimp paste contained more esters,which was similar to the umami aroma profile of raw shrimp.Interestingly,pyrazines were only produced in fermented shrimp paste samples,suggesting that they were produced during the fermentation process and they may contribute unique roasted and meaty aromas,which were important for the overall aroma characteristics of shrimp paste.
基金supported by the National Natural Science Foundation of China,Science Foundation of Two Sides of Strait(No.U2005209)。
文摘Due to the premium flavor,Qingxin oolong tea(QOT),which is grown and produced in Taiwan,is widely appreciated.Roasting is a crucial process for shaping its flavor.However,the effect of roasting on the aroma and taste of QOT was not fully understood.In this study,the volatile composition,aroma-active compounds and phenolic profile of QOT with different roasting degrees,including the unroasted(UR),the medium roasted(MR)and the heavy roasted(HR)were analyzed.As revealed by headspace solid phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS)and multivariate statistical analyses,UR and MR demonstrated similar volatile profiles,while heavy roasting changed the volatile composition greatly.Multiple nitrogen-containing compounds,such as 3,5-diethyl-2-methylpyrazine and 2-ethyl-3,5-dimethylpyrazine,were uniquely found in heavy roasted samples,which can be ascribed to the extensive Maillard reaction.Moreover,eight compounds were identified and verified as key aroma-active compounds by using gas chromatography-olfactometry-mass spectrometry(GC-O-MS),aroma recombination and omission experiments.The aldehydes and alcohols,such as linalool,benzeneacetaldehyde andα-farnesene,with a floral scent were the dominant aroma-active compounds in UR and MR,while 2-ethyl-3,5-dimethylpyrazine and 3,5-diethyl-2-methylpyrazine with a roasted scent were the main aroma-active compounds in HR.Furthermore,as revealed by ultra-high performance liquid chromatography and Orbitrap high resolution mass spectrometry(UHPLC-Q-Orbitrap-MS),flavanols and phenolic acids were significantly lower in abundance in UR and MR as compared to those in HR,whereas flavonols were less affected by roasting.These findings provide useful information for understanding the flavor characteristics of this popular oolong tea for the first time.
