Comparison of simultaneous distillation extraction and solid-phase micro-extraction for determination of volatile constituents in tobacco flavor

The volatile and semi-volatile components in tobacco flavor additives were extracted by both simultaneous distillation extraction and solid-phase micro-extraction. Extraction conditions for solid-phase micro-extraction were optimized with information theory. Then, detection were accomplished by gas chromatography-mass spectrometry. Characteristic of each method was compared. Qualitative analysis and quantitative analysis of 6# tobacco flavor sample were accomplished through both simultaneous distillation extraction and solid-phase micro-extraction. The experimental results show that solid-phase micro-extraction method is the first choice for qualitative analysis and simultaneous distillation extraction is another good selection for quantitative analysis. By means of simultaneous distillation extraction, 20 components are identified, accounting for 92.77% of the total peak areas. Through solid-phase micro-extraction, there are 17 components identified accounting for 91.49% of the total peak areas. The main aromatic components in 6# tobacco flavor sample are propanoic acid, 2-hydroxy-, ethyl ester, menthol and menthyl acetate. The presented method has been successfully used for quality control of tobacco flavor.

Volatile Flavor Composition in Mutton of Ningxia Tan Sheep

[Objective] To analyze the volatile flavor compounds in mutton of different parts of Ningxia Tan sheep. [Method] The volatile flavor compounds in mutton were identified and quantified using the solid phase micro-extraction （SPME） method combined with GC-MS analysis. [ Re- sult ] The proportion of aldehydes in volatile compounds was the highest in the mutton of most parts of Ningxia Tan sheep, but no 4-methyl acid and 4-methyl nonyl acid was detected in the mutton. [ Conclusion]Aldehydes may be important for the volatile flavor of mutton of Ningxia Tan sheep. The study provides a basis for better development and use of Ningxia Tan sheep.

Time-dependent categorization of volatile aroma compound formation in stewed Chinese spicy beef using electron nose profile coupled with thermal desorption GC–MS detection

In the present study,flavor profiles of Chinese spiced beef in the cooking process were comparatively analyzed by electronic nose,gas chromatography–mass spectrometry(GC–MS)with a thermal desorption system(TDS),and solid-phase microextraction(SPME).A total of 82 volatile compounds were identified,and 3-methyl-butanal,pentanal,hexanal,-xylene,heptanal,limonene,terpinene,octanal,linalool,4-terpinenol,-terpineol,and(E)-anethole were identified as the characteristic flavor compounds in Chinese spiced beef.Variation in the content of volatile components produced by different cooking processes was observed.In general,a cooking time of 4 h resulted in optimal flavor quality and stability.Results indicated that the electronic nose could profile and rapidly distinguish variation among different cooking time.The volatile profiling by TDS-GC–MS and responses from the electronic nose,in combination with multivariate statistical analysis,are a promising tool for control the cooking process of spiced beef.

Method Optimization Study on Isolation of Volatile Compounds by Headspace Solid-Phase Microextraction (HS-SPME) from Custard Apple (<i>Annona squamosa</i>L.) Pulp.

Aroma is an important quality parameter, which can help in delaying degradative processes and hence understanding the volatile compounds that are part of an aroma is extremely important. Thus, the aim of this study was to isolate the volatile compounds present in custard apple (Annona squamosa L.) pulp by solid-phase microextraction (SPME) technique using 3 different fibers (DVB/CAR/PDMS, PDMS and PDMS/DVB). An experimental design was set up to evaluate the best extraction conditions wherein the variables were extraction temperature (minimum 28°C, maximum 62°C), ionic strength (minimum 0, maximum 30.0%) and sample concentration (min 1, max 99.0%). The separation of volatiles was achieved in chromatographic columns of different polarity (polar and non-polar) while identification of volatile compounds was performed by high resolution gas chromatography system coupled with mass spectrometry. The results obtained using 3 different fibers revealed the isolation of 71 compounds with fiber DVB/CAR/PDMS, while only 30 and 21 compounds were isolated using fibers PDMS/DVB and PDMS, respectively. The major classes of compounds identified were terpenes, esters, alcohols and aldehydes. Optimum conditions for obtaining higher number of volatiles for non-polar column were 45°C for extraction temperature, 15% of sodium chloride and 50% of pulp amount which resulted in isolation of a maximum of 78 peaks.

Flavor profile variations of Huangjiu brewed in different traditional Chinese solar terms

Background:Through long-term research on Huangjiu fermentation,it has been found that the quality of Huangjiu is closely associated with Chinese 24-solar term.Therefore,this study was conducted to explore the characteristic and property index differences of Huangjiu,such as aroma and flavor profile,and physicochemical properties—brewed in different solar terms by choosing five representative fermentation times of Shaoxing Huangjiu.Results:Huangjiu samples in the current study all met the national standards of traditional semi-dry Huangjiu.There are significant differences in physicochemical properties such as acidity and amino nitrogen among different solar-term groups.Forty three detected volatiles were applied by principal component analysis and partial least squares discriminant analysis analyses to differentiate the main factors.Volatiles mainly loaded to four principal components,which accounted for 86.5%.Nineteen volatiles were discriminated to significantly differentiate solar-term groups.Odor activity values(OAV)analysis found 14 compounds with OAV>1,while correlation analysis between volatiles and the outcomes of sensory evaluation displayed the various properties of Huangjiu on aroma and flavor due to the various combinations of volatiles,reducing sugar,acidity and amino nitrogen.After a national wine inspector evaluated and scored Huangjiu fermented in different solar terms,Huangjiu brewed in Winter Solstice exhibited the highest performance,with a score of 91.0,and praised as a kind of gold medal product.Conclusion:The methodology of this study can help to produce more types of appealing flavor and aroma of alcoholic beverages to consumers,build varietal Huangjiu or other alcoholic beverages through fermenting guidance by solar term,and even expand the applications of the traditional Chinese 24-solar term.