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《Flavour and Fragrance Journal》2017,32(2):85-91
Vanillin can be obtained by extraction from the pods of Vanilla (organic vanillin), by synthetic pathways using different precursors (mainly lignin and guaiacol), and by enzymatic bioconversion (biovanillin) from natural precursors, (mainly ferulic acid, eugenol and isoeugenol, and turmeric acid). Based on the origins its commercial value greatly changes. At the same time the European Regulation allows to label food discriminating between the sources of the ingredient indicating the term ‘natural’ even if the ingredient is obtained by biosynthetic pathways. However from literature it is apparent that the distinction between synthetic and biosynthetic vanillin is not always possible, while the natural one can be easily discriminated, although rarely used. The method here proposed is based on head‐space solid‐phase microextraction and gas chromatography coupled to isotope ratio mass spectrometry to determine the carbon isotope ratio (δ13C) of vanillin extracted from vanilla pods, commercial flavoured foodstuff and in vanillin samples of different origins. Isotope fractionation during SPME extraction has been determined based on sample's isotopic composition. The results confirm the literature ones and allow to reveal which biovanillin can be easily characterized and distinguished from the synthetic ones. In most cases it has been possible to evaluate the origin of vanillin used in the different food preparations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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An evaluation of comprehensive two‐dimensional (2D) gas chromatography (GC×GC) was performed to assess its suitability for the analysis of volatile fragrance components, recognized by the European Commission's Scientific Committee on Cosmetics and other Non‐food Products (SCCNFP) as possible skin sensitizers. The 24 volatile components listed by the SCCNFP were baseline‐resolved or better within one 30 min analysis. High‐quality calibration data for standard mixtures were obtained, with R2 > 0.998 over the concentration range 2–1000 mg/l. However, the analysis of small spiked amounts of target compounds in truly complex fragrances was problematic, due to uncertainty in component assignment. The benefits and limitations of GC×GC are reported, and a discussion of the proposed directions for the solution of this analysis is provided. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Ignacio Ontan Juan Tllez Vicente Ferreira Ana Escudero 《Flavour and Fragrance Journal》2019,34(2):75-89
The use of home appliances can cause various problems. In the case of dishwashers, the generation of bad odours is one of the most serious problems for users. Odours inside dishwashers are mainly caused by the presence of food residues. A study using gas chromatography‐olfactometry (GC‐O has been carried out to establish how different food residues produce differences in the odours found in dishwashers. A total of 49 compounds were identified in the 109 odour zones detected. Dimethyl trisulfide and methanethiol/dimethyl sulfide were the most significant compounds in most of the situations studied. Some of these compounds were selected to generate an ‘odorous atmosphere’ that was subjected to chemical and sensory analysis. Treatments for the elimination of odours, designed to alter the odours, were applied to this atmosphere before performing chemical (GC‐MS) and sensory analyses. The sensory analysis was carried out to determine the intensity and hedonic tone of the odorous atmosphere. Differences between treatments were found. 相似文献
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Yajing Shao Philip Marriott Robert Shellie Helmut Hügel 《Flavour and Fragrance Journal》2003,18(1):5-12
Ginger (Zingiber officinale) headspace has been studied by using solid‐phase microextraction (SPME), combined with comprehensive two‐dimensional (2D) gas chromatography (GC × GC). A 100 µm PDMS fibre proved to be the most useful in the present study. SPME–GC–MS analysis was also performed to identify the components extracted from the volatile fraction. The ease of SPME makes it a useful tool for qualitative comparison of samples, and here fresh ginger was contrasted with a crystallized ginger sweet. The latter sample had fewer of the more volatile components, but the heavier components appeared to compare well in the two samples. The use of SPME as a sample introduction method for GC × GC was investigated, using the two different ginger samples. The correspondence of retention times in the 2D separation space was found to be excellent, and should allow reliable identification of the compounds if adequate standards or comparative retentions of known components are available. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Kayu Okutsu Yumiko Yoshizaki Mai Kojima Kazuya Yoshitake Hisanori Tamaki Takamine Kazunori 《Journal of the Institute of Brewing》2016,122(1):168-174
Imo‐shochu is a Japanese traditional spirit made from sweet potatoes. Characteristic volatile compounds in imo‐shochu are mainly derived from the sweet potato and its flavour significantly depends on the quality and cultivar of sweet potato used. Thus, the effects of the cultivation period of sweet potatoes on sensory characteristics and composition of volatile compounds of imo‐shochu were investigated. Sweet potatoes (cv. Koganesengan) used in this study were harvested at 120, 150 or 180 days after planting, and each sample was used to prepare imo‐shochu. The imo‐shochu samples were evaluated by eight panellists in a blind study, who ranked them on the basis of various odour and taste attributes. Rank sums were calculated and data were analysed using the Friedman test. The compositions of the volatile compounds in the imo‐shochu samples were analysed using gas chromatography–mass spectrometry (GC‐MS). Sensory evaluations showed that a longer cultivation period of the sweet potatoes enhanced the floral aroma and characteristic taste of imo‐shochu. In addition, imo‐shochu prepared with the sample cultivated for 150 days was evaluated to have a sweeter taste than that prepared with the other samples. The GC‐MS analysis showed that imo‐shochu prepared with the sample cultivated for 180 days contained a lower concentration of monoterpene alcohols, but higher concentrations of β‐damascenone, rose oxide, and fatty acid esters than the imo‐shochu prepared with the sample cultivated for 120 days. These differences in the composition of the volatile compounds affected the sensory qualities of the imo‐shochu. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
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In comprehensive 2D gas chromatography, the entire sample is simultaneously subjected to analysis on two capillary columns. By using a suitable modulation interface between the primary and secondary columns, hundreds of fast, second‐dimension chromatograms are produced. The data from these chromatograms are treated such that a 3D surface plot or a 2D contour plot of the components' individual retention times, on each column, as well as peak responses, are represented. In a properly tuned comprehensive 2D chromatogram, the individual sample components are spread throughout a 2D separation space, providing a significant increase in the probability of resolving a greater number of sample components without increasing the analysis time. Comprehensive 2D–GC has proved useful for high‐resolution conventional essential oil analysis as well as high‐resolution enantioselective essential oil analysis. Combining comprehensive 2D–GC with either a quadrupole or time‐of‐flight mass spectrometer gives a powerful 3D analysis technique, which is extremely effective for complex sample analysis. The present status and opportunities arising from these ultra‐high resolution approaches are discussed herein. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Violeta T. Pardio Maria D. Mariezcurrena Krzysztof N. Waliszewski Victor Sánchez Mariusz K. Janczur 《International Journal of Food Science & Technology》2009,44(12):2417-2423
The effects on the aroma compositions of ethanol extracts obtained by traditional and enzyme‐assisted methods from seven killing conditions used in vanilla pod curing were studied. Two procedures of vanilla pod killing consisted of either freezing pods at ?10 °C for 24 h or immersing pods in 80 °C water for 10 s each of three times with 30 s intervals resulted in the highest vanillin values in terms percentage of dry weight of the bean (2.84 and 2.96), 4‐hydroxybenzaldehyde (0.18 and 0.20), vanillyl alcohol (0.56 and 0.57) and vanillic acid (0.18 and 0.19 respectively) when traditional vanilla ethanol extraction was used. When this extract was aged for 3 months it showed improvement in flavour compounds. Enzyme‐assisted vanilla ethanol extraction showed a higher content of flavour compounds than traditional extract, for example vanillin 4.38% and 2.96% respectively. Only vanillic acid levels were improved after ageing of the enzyme‐assisted extracts. 相似文献
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Zuobing Xiao Shengjiang Liu Yongbo Gu Na Xu Yi Shang Jiancai Zhu 《Journal of food science》2014,79(3):C284-C294
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Qian Fan Xinlei Wang Yuefeng Zhao Fuping Zheng Hehe Li Fuyan Zhang Yuhang Zhang Feng Chen 《Flavour and Fragrance Journal》2019,34(6):514-525
Laobaigan (LBG) Baijiu is recognized as one of the famous Chinese liquors due to its unique flavor characteristics. However, its key aroma‐active volatiles are still unknown. In this study, 414 volatile chemicals in the LBG Baijiu were initially detected by comprehensive two‐dimensional gas chromatography‐time‐of‐flight mass spectrometry (GC×GC‐TOF/MS). Then, 52 of them were determined by sample dilution analysis (SDA) for screen of aroma‐active compounds. Based on their odor–activity values (OAVs) that were determined by the external standard method performed on the GC×GC‐TOF/MS, 32 volatile compounds were further recognized as important odorants, which were reconstituted to simulate and validate the aroma profile of the LBG Baijiu. Moreover, omission experiments were conducted to corroborate the importance of key odorants. As a result, nine aroma compounds were finally confirmed as the key aroma‐active compounds of the LBG Baijiu. 相似文献
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During storage of shredded cabbage, characteristic sulfurous volatile compounds are formed affecting cabbage aroma both negatively and positively. Selected ion flow tube‐mass spectrometry (SIFT‐MS) was used to measure the concentration of cabbage volatiles during storage. The volatile levels of cabbage samples were measured at pH 3.3 to 7.4 at 4 °C for 14 d, and pH 3.3 at 25 °C for 5 d in order to determine the effect of pH and temperature. Aroma intensity, best aroma, freshness, and off odor were evaluated in a sensory test of the samples at 4 °C. The desirable volatile allyl isothiocyanate was lower in high pH samples (pH 7.4 and 6.4), whereas higher concentrations were detected in low pH samples (pH 3.3 and 4.6). Lipoxygenase volatiles, which produce a fresh green and leafy aroma in cabbage, were generated in very low amounts at any pH value. High pH samples generated significantly higher concentrations of off odors such as dimethyl sulfide, dimethyl disulfide, dimethyl trisulfide, and methanethiol. Sensory tests showed that higher pH samples had significantly stronger off odor and lower desirable cabbage aroma than lower pH samples. Thus, sensory results matched the volatile results in that samples at higher pH levels formed the highest amount of undesirable volatiles and the least amount of desirable volatiles. Storage at 25 °C produced similar concentrations of allyl isothiocyanate, but significantly higher levels of off odors, than at 4 °C. Shredded cabbage products should be stored in low pH dressings to minimize formation of off odors and maximize formation of characteristic, desirable cabbage odor. 相似文献
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Chen MZ Trinnaman L Bardsley K St Hilaire CJ Da Costa NC 《Journal of food science》2011,76(7):C1032-C1038
North American peppermint oils are widely regarded as some of the most superior peppermint oils commercially available. Amongst them is Yakima double-cut peppermint oil (Mentha piperita L.). It has an aroma described as strong, refreshing, minty, slightly creamy, and very herbaceous with some of the most desirable flavor notes among peppermint oils. The peppermint is grown in the Yakima Valley of Washington State, USA. As one of the most northerly grown peppermints with longer days, it is unique as there are 2 harvests of the mint leaves in one season. For this study, samples of fresh and dried (hay) leaves were collected from both harvests; 1st cut, July and 2nd cut, September. Steam-distilled oils were produced from each harvest and analyzed by gas chromatography-mass spectrometry to give detailed profiles. The aroma and taste sensory attributes of each oil were evaluated. In addition, menthyl formate has previously been reported only once in the literature, but not as definitively as required by current flavor-regulatory bodies for use as a natural flavoring ingredient. It was conclusively reported in these peppermint oils. 相似文献
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Negative aromas such as rancid, fusty, winey‐vinegary and frozen are sensory attributes of defective virgin olive oil recognized by the International Olive Council. Solid phase microextraction‐gas chromatography/mass spectrometery (SPME‐GC/MS) was employed to establish a flavour profile for each defective oil. The potential contribution of the identified compounds to the overall aromas of oil samples was assessed by calculating the ratio relative area/odour threshold in air – Relative Area over Threshold (RAOT). The relevant compounds of each defective sensory attributes were suggested: a series of C7‐C12 unsaturated aldehydes, such as 2, 4‐heptadienal, E‐2‐nonenal and E‐2‐octenal, were found to be responsible for rancidity, Z‐3‐hexenyl acetate and nonanoic acid were related to fusty defects, acetic acid and butyric acid were responsible for winey‐vinegary defects, and limonene was found as a relevant compound in frozen oil. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献