In order to explore the difference in aroma quality of dried jujube and its different extracts, headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with electronic nose was used to investigate the volatile components of dried jujube and its extracts and absolute oils obtained by heat reflux extraction and microwave-assisted heat reflux extraction. The results showed that a total of 96 volatile components were detected in dried jujube and its extracts, the major aroma components being acids, esters, aldehydes and ketones. The relative content of acidic volatile components was the highest in the extract and absolute oil obtained using heat reflux extraction, 44.433% and 39.304%, respectively, and their contents of volatile ketones were significantly higher than those of the other samples (P < 0.05). The highest relative content of volatile esters of 52.196% and 45.863% was observed in the extract and absolute oil obtained using microwave-assisted heat reflux extraction, respectively. According to the results of GC-MS and electronic nose, the two absolute oils, extracted from the extracts, respectively, had similar aroma characteristics. The results of loading analysis showed that the aroma components of dried jujube and its different extracts could be recognized by sensors W1S, W1W, W2S and W2W. In general, HS-SPME-GC-MS combined with electronic nose can be used toevaluate the difference in aroma quality of dried jujube and its extracts.

Headspace solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was used to analyze the volatile aroma components of vanilla extract. The characteristic flavor compounds of vanilla extract were analyzed by a sensory-guided approach based on olfactory threshold and odor activity value (OAV) and reconstituted by aroma recombination test. The results showed that 83 aroma compounds were detected in vanilla extract, and 34 aroma components contributing to creamy, sweet, sour, acidic aroma, balsamic, burnt, bean-like and spicy aroma notes were found to be closely related to the characteristic flavor of vanilla extract. According to their OAV values, 14 aroma compounds including vanillin, 4-(ethoxymethyl) phenol, 2-methoxy-phenol, acetic acid, 4-vinyl guaiacol, and vanillin ethyl ether were identified as the key components contributing to the characteristic flavor of vanilla extract. The aroma recombination sample of these characteristic flavor compounds had vanilla-like creamy, sweet, smoked and sour aromas, and could be used to identify the characteristic aroma of vanilla with a sensory similarity of 92.33%, indicating that the 14 characteristic flavor compounds can be used as key indicators for quality control of natural perfumes with the characteristic flavor of vanilla and provide a material basis for the reconstitution of food additives with the characteristic flavor of vanilla.

In this study, headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and gas chromatography-olfactory (GC-O) were applied to identify and analyze the volatile aroma compounds of the ethanol extract of figs. Its key characteristic flavor compounds were analyzed by odor activity (OAV) and aroma recombination and omission tests. The results showed that a total of 40 volatile aroma components were identified, of which 18 compounds, such as isobutyrate, γ-butyl lactone, aromatic camphor, nonaldehyde, vanillin and furfural, were important aroma components in the fig extract (OAV > 1). The aroma recombination experiments showed that the sensory properties of the recombined samples, which had typical aroma characteristics such as fruity, sweet, baked and burnt sweet with slight sour, ointment-like and milky, were similar to those of the fig extract. Furthermore, the aroma omission experiments identified gamma-hexanoate, ethyl palmitate, phenmethanol, aromatic camphor, vanillin, benzaldehyde, 4-hydroxy-2,5-dimethyl-3(2H)-furan, 5-hydroxymyfuran, and methyl cyclopentanolone as key characteristic flavor compounds of the fig extract. The findings of this study provide a theoretical basis for the development and quality control of fig characteristic flavorings.