Quantification Of Volatile Compounds Research Articles

Impact of Long-term Fasting on Breath Volatile Sulphur Compounds, Inflammatory Markers and Saliva Microbiota Composition.

Despite substantial evidence supporting the role of resident bacterial communities in therapeutic fasting outcomes, research has primarily focused on gut microbiota, leaving changes in oral microbiota largely unexplored. The clinical significance of oral health changes during fasting is nonetheless underscored by the documented development of halitosis in fasting individuals. However, no scientific studies have comprehensively examined the interplay between salivary microbiota alterations, inflammatory changes in the gingival crevice, and the production of malodorous volatile compounds. We examined volatile sulphur compounds (VSC) in breath during fasting, cytokine levels in the gingival crevice, and oral microbiota composition of the saliva in a single-arm interventional study involving 36 subjects who fasted for 10 ± 3 days. Participants fasted according to Buchinger fasting guidelines. VSC were evaluated every morning before any food or drink intake using the OralChroma gas chromatography device. Saliva and gingival crevicular fluid (GCF) samples were collected at the clinical site before fasting, at the end of fasting, and at the end of food reintroduction. Follow-up saliva samples were sent to the patients after 1 and 3 months. Saliva samples were processed and analysed by targeted sequencing of 16S rRNA gene amplicons, whereas the expression of 6 inflammatory markers in the GCF were analysed using a multiplex fluorescent bead-based immunoassay. The quantification of volatile compounds in the breath demonstrated a statistically significant increase in dimethylsulfide levels during fasting, which corroborates the occurrence of bad breath as a common side effect of fasting. Salivary microbiota profiling showed a shift in microbial composition, including reduction in the levels of Neisseria, Gemella and Porphyromonas spp., concomitant with an increase in the levels of Megasphaera, Dialister, Prevotella, Veillonella, Bifidobacteria, Leptotrichia, Selenomonas, Alloprevotella, and Atopobium. We further demonstrated a reduction in the levels of the pro-inflammatory cytokine interleukin-8 in the GCF. Dimethylsulfide concentrations in the breath increased during fasting, and this was correlated to changes in the oral microbiota. Future studies are needed to illuminate the possible impact of these changes on oral and general health status.

Statistically sound identification of compounds by low-resolution GC-MS: Identification of tear agents in tear gas sprays

Gas-chromatography hyphenated with low-resolution mass spectrometry is a very flexible tool for the cost-effective identification and quantification of volatile compounds in complex matrices. In some analytical fields, criteria for the agreement between retention time and mass spectra of the analyte in calibrators and samples are defined based on the general understanding of the performance of these parameters. However, since this harmonisation is not based on experimental performance observed for specific GC-MS conditions and analyte it leads to false identifications. This research proposes a novel and robust tool for defining statistically sound criteria for the identification of compounds by GC-MS and LC-MS using experimental data. The Monte Carlo Method (MCM) simulation of the correlated abundance of characteristic ions of analyte mass spectrum allows simulating the abundance ratio difference of the analyte in a calibrator and sample used for statistically sound identifications. The Cholesky decomposition of the covariance matrix of ion abundances for MCM simulations allows the reliable use of many ion abundance ratios in identifications. The developed methodology was implemented in a user-friendly Excel spreadsheet and applied to the identification of tear gas agents in tear gas sprays. Criteria defined by SANTE for identifying pesticide residues in foodstuffs were compared with the developed tool. The cross-validation of computational and SANTE tools allowed concluding that the statistical control of retention time and mass spectra performs according to the defined confidence level. On the other hand, the SANTE criteria can produce up to 92 % false identifications for being too strict considering signal dispersion.

Flavoromic analysis of wines using gas chromatography, mass spectrometry and sensory techniques

Various sensory perceptions drive the quality and typicality of wines, with the volatile profile playing a fundamental role in the characteristics of odor, aroma and consequently flavor, which combines the smell (odor and aroma), taste, and trigeminal sensations. Efforts have been made in both the field of instrumental and sensory analysis to understand the relationship of volatile compounds with sensory attributes in omics approaches. Gas chromatography (monodimensional and two-dimensional (heartcutting and comprehensive)) associated with mass spectrometry (GC/MS, GC-GC/MS and GCxGC/MS) and chemometric tools have contributed to foodomics analyses, specifically those linked to metabolomics/volatilomics. These tools, along with the elucidation of sensory properties (sensomics), lead to advanced results in the field of flavoromics. They also help to define the best practices in both vineyard management and winemaking that enable the production of high-quality wines. The objective of this review is to report the challenges of determining the volatile profile of wines, pointing out the ways that can be followed in successful identification and quantification of volatile compounds. The state of the art of sensory evaluation methods is also addressed, providing information that helps in choosing the most appropriate sensory method to be conducted with chromatographic analysis to achieve more in-depth results in the field of flavoromics.

Discrimination and quantification of volatile compounds in beer by FTIR combined with machine learning approaches

The composition of volatile compounds in beer is crucial to the quality of beer. Herein, we identified 23 volatile compounds, namely, 12 esters, 4 alcohols, 5 acids, and 2 phenols, in nine different beer types using GC–MS. By performing PCA of the data of the flavor compounds, the different beer types were well discriminated. Ethyl caproate, ethyl caprylate, and phenylethyl alcohol were identified as the crucial volatile compounds to discriminate different beers. PLS regression analysis was performed to model and predict the contents of six crucial volatile compounds in the beer samples based on the characteristic wavelength of the FTIR spectrum. The R2 value of each sample in the prediction model was 0.9398–0.9994, and RMSEP was 0.0122–0.7011. The method proposed in this paper has been applied to determine flavor compounds in beer samples with good consistency compared with GC–MS.

Volatilome: Smells like microbial spirit.

In recent years, the study of volatile compounds has sparked interest due to their implications in signaling and the enormous variety of bioactive properties attributed to them. Despite the absence of analysis methods standardization, there are a multitude of tools and databases that allow the identification and quantification of volatile compounds. These compounds are chemically heterogeneous and their diverse properties are exploited by various fields such as cosmetics, the food industry, agriculture and medicine, some of which will be discussed here. In virtue of volatile compounds being ubiquitous and fast chemical messengers, these molecules mediate a large number of interspecific and intraspecific interactions, which are key at an ecological level to maintaining the balance and correct functioning of ecosystems. This review briefly summarized the role of volatile compounds in inter- and intra-specific relationships as well as industrial applications associated with the use of these compounds that is emerging as a promising field of study.

Simultaneous quantification of six flavouring agents in herbal freshness gel toothpaste by gas chromatography

AbstractThere are many methods reported to identify and quantify volatile compounds. Many of them are based on chromatographic techniques, such as high‐performance liquid chromatography (HPLC), gas chromatography with flame ionization detector (GC‐FID), and GC coupled with mass spectrometry (GC–MS). But among all GC‐FID and GC–MS are majorly used for the detection and quantification of volatile compounds. A new gas chromatographic method has been developed for simultaneous determination of six flavouring agents [menthol, benzyl alcohol, methyl salicylate, anethole, menthol carboxamide (WS‐3) and eugenol] in herbal freshness gel toothpaste. All six flavours were separated using a DB‐WAX (Agilent) capillary GC column (30 m × 0.25 mm × 0.25 μm) and flame ionization detector (FID). This method was validated for various parameters such as precision, linearity, accuracy, stability, robustness, limit of detection, and limit of quantification as per ICH guidelines, AOAC internationals Appendix K. All the validation parameters were found to be within acceptable limits. The method was successfully applied for the quantification of all flavouring agents in toothpaste formulations.

Optimization of the Fermentation Conditions of Huaniu Apple Cider and Quantification of Volatile Compounds Using HS-SPME-GC/MS.

The fermentation process and composition of volatile compounds play a crucial role in the production of Huaniu apple cider. This study aimed to optimize the fermentation conditions of Huaniu apple cider and quantify its volatile compounds using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC/MS). The optimal fermentation parameters were determined using response surface methodology (RSM). The optimal fermentation temperature was 25.48 °C, initial soluble solids were 18.90 degrees Brix, inoculation amount was 8.23%, and initial pH was 3.93. The fermentation rate was determined to be 3.0, and the predicted value from the verification test was 3.014. This finding demonstrated the excellent predictability of a RSM-optimized fermentation test for Huaniu apple cider, indicating the reliability of the process conditions. Moreover, the analysis of volatile compounds in the optimized Huaniu cider identified 72 different ingredients, including 41 esters, 16 alcohols, 6 acids, and 9 other substances. Notably, the esters exhibited high levels of ethyl acetate, ethyl octanoate, and ethyl capricate. Similarly, the alcohols demonstrated higher levels of 3-methyl-1-butanol, phenethylethanol, and 2-methyl-1-propanol, while the acids displayed increased concentrations of acetic acid, caproic acid, and caprylic acid. This study provides the essential technical parameters required for the preparation of Huaniu apple cider while also serving as a valuable reference for investigating its distinct flavor profile.

Perspectives on using ethanol as an internal standard for the quantification of volatile compounds in alcoholic products by headspace SPME–GC/FID without sample preparation

For the first time, the beneficial “Ethanol as Internal Standard (IS)” method developed for the analysis of alcoholic products was tested in headspace mode of solid-phase microextraction gas chromatography with flame ionization detector (SPME-GC/FID) and compared with the traditional IS method. The extraction and separation conditions were optimized for the analysis of 10 volatile congeners prescribed in European legislation: acetaldehyde, methyl acetate, ethyl acetate, methanol, butan-2-ol, propan-1-ol, 2-methylpropan-1-ol (isobutanol), butan-1-ol, 1,1-diethoxyethane (acetal), and 3-methylbutan-1-ol (isoamylol). To evaluate the accuracy of the compared methods, three real alcoholic product samples with ethanol content of 20%, 40%, and 80% v/v were spiked with gravimetrically prepared standard solutions to calculate recoveries. The obtained data indicates that the suggested method can be employed as a robust and accurate tool for SPME analysis of alcoholic products with low ethanol content, such as wines. It was also observed that an increase in ethanol content in the matrix affects the accuracy of the “Ethanol as IS” method, potentially due to non-linearity of analyte extraction. However, in the case of wine sample, the “Ethanol as IS” method showed significantly better results compared to the traditional approach. The precision of the suggested method, evaluated using relative standard deviations (RSD) of obtained concentrations was found to be comparable to that of the traditional method.Graphical abstract

Comparing the antioxidant properties and volatile compounds of carrot-orange juice blend processed through varied chemical, pasteurization and ultrasound conditions

Ultrasound technique is one of the green technologies that is being utilized widely for varying food processes. Our aim in this study was to carry out ultrasonication, pasteurization and chemical preservation (Potassium metabisulfite) techniques on a carrot-orange juice blend. Additionally, the effect of these treatments on the storage period of about 21 days was also determined. The study displayed an array of results under the effect of different treatments. Throughout the storage period of 21 days’ significant results were presented by the carrot juice blend subjected to the ultrasound technique (25 min) giving the highest values for total phenolic content (25.56 ± 1.29 mg GAE/100 mL), total antioxidant activity (573.48 ± 2.29 mg Trolox /100 mL), DPPH (32.32 ± 1.83 %) and reducing power (45.45 ± 1.92 mg AAE/100 mL) with least deterioration, followed by the blends treated with potassium metabisulfite (KMS) and pasteurization. The physicochemical analysis showed a non-significant effect of treatments on pH and total soluble solids (oBrix) of carrot-orange juice blends whereas, the changes in color parameters L*, a* and b* were noted to show changes in treated blends. Similarly, the results for the GC–MS quantification of volatile compounds displayed the highest concentrations in the ultrasonicated blends as compared to other techniques. The peak quantity was obtained for the hexanal (9903.43 ± 7.61 μg.kg−1) followed by 3-Methylbutanal (2638.7 ± 5.44 μg.kg−1), terpinolene (2337.16 ± 5.28 μg.kg−1), elemicin (2198.28 ± 5.28 μg.kg−1), myristicin (1936.62 ± 6.72 μg.kg−1). The use of sonication can effectively enhance the nutritional qualities of juice, as perceived by consumers.

Method for the analysis of volatile compounds in virgin olive oil by SPME-GC-MS or SPME-GC-FID

During the course of the EU H2020 OLEUM project, a harmonized method was developed to quantify volatile markers of the aroma of virgin olive oil with the aim to support the work of sensory panel test to assess the quality grade. A peer validation of this method has been carried out, with good results in terms of analytical quality parameters. The method allows the quantification of volatile compounds by SPME-GC with two possible detectors, flame ionization detector and mass spectrometry, depending on the technical facilities of the labs applying this method. The method was optimized for the quantification of 18 volatile compounds that were selected as being markers responsible for positive attributes (e.g. fruity) and sensory defects (e.g. rancid and winey-vinegary). The quantification is carried out with calibration curves corrected by the internal standards. Additionally, a protocol is provided to prepare the calibration samples. This procedure enhances reproducibility between labs since one of the main sources of errors is the application of different procedures in calibration.

Quantitative Measurement Reveals Dynamic Volatile Changes and Potential Biochemical Mechanisms during Green Tea Spreading Treatment.

Quantitative data provide clues for biochemical reactions or regulations. The absolute quantification of volatile compounds in tea is complicated by their low abundance, volatility, thermal liability, matrix complexity, and instrumental sensitivity. Here, by integrating solvent-assisted flavor evaporation extraction with a gas chromatography-triple quadrupole mass spectrometry platform, we successfully established a method based on multiple reaction monitoring (MRM). The method was validated by multiple parameters, including the linear range, limit of detection, limit of quantification, precision, repeatability, stability, and accuracy. This method was then applied to measure temporal changes of endogenous volatiles during green tea spreading treatment. In total, 38 endogenous volatiles were quantitatively measured, which are derived from the shikimic acid pathway, mevalonate pathway, 2-C-methylerythritol-4-phosphate pathway, and fatty acid derivative pathway. Hierarchical clustering and heat-map analysis demonstrated four different changing patterns during green tea spreading treatment. Pathway analysis was then conducted to explore the potential biochemistry underpinning these dynamic change patterns. Our data demonstrated that the established MRM method showed high selectivity and sensitivity for quantitative tea volatile measurement and offered novel insights about volatile formation during green tea spreading.

Analysis of an ampoule found on a WW2 German soldier: Poison or medicine?

During archaeological excavations in Maltot, Normandy (France), the remains of a German soldier probably dating from Operation Jupiter (July 10–11, 1944) were discovered. The study of the body showed that he was a man aged 17 to 20 at the time of death. His death was likely caused by several recent projectile impacts: bullet entry orifice in the skull and several shrapnel traces in the upper limbs. Several objects were found near the body, including the remains of a leather and metal box at the level of is abdomen containing about ten glass whole ampoules while 2 others laid loose. The objective of this work was to identify the contents of these ampoules, with an emphasis on poisons. Screenings were carried out on the contents of the vial using HPLC-DAD, GC-MS, HS-GC-MS and HR-LC-MS/MS. Multi-element research by ICP-MS was also conduct as well as cyanide research. Volatile compounds quantification was performed using GC-MS equipped with a Triplus AS Head space injector (Thermo Fisher Scientific, Les Ulis, France). Chromatographic separation was achieved on a Rtx-VMS column (30 m × 0.25 mm, dF = 1.4 μm) (Restek, Lisses, France) with helium as carrier gas at a constant flow rate of 1.2 mL/min. Injector temperature was held at 65 °C and split injection mode was employed with a split flow of 80. The GC conditions were as follows: column temperature started at 40 °C, was held for 2 min then increased to 150 °C at a rate of 10 °C/min then held for 1minute. 5 μL of the sample was put in a sealed vial then heated to 80 °C during 20 minutes with a 10 second agitation step. 0.2 mL of the gas phase was injected in the GC/MS. Data acquisition was performed using the Xcalibur v2.1 software (Thermo Fisher Scientific). The detection was operated in SIM mode. Propan-1-ol was used as internal standard (E.I.). Calibrators were prepared at 50, 100, 200, 500 and 1000 mg/L in DMSO. Analyzed ampoule was 6 cm long and 0.5 cm wide and contained approximately 300 μL of a colorless, water-immiscible liquid, with a characteristic solvent odor. HPLC-DAD, GC-MS, HR-LC-MS/MS, ICP-MS and cyanide screenings were negative. However, the HS-GC-MS analysis revealed the presence of several volatile products: ethanol (360 g/L), chloroform (392 g/L), diethyl ether (87 g/L), as well as isopropanol, trichloroethylene and tetrachloroethylene at concentrations lower than 5 g/L. No poison but two anesthetic substances (chloroform and diethyl ether) associated with an alcoholic solvent (ethanol) were found. Therefore, the soldier was probably a medic. The anesthetic properties of ether were discovered in 1846 leading to a revolution in surgery and the beginnings of anesthesia. A few months later, the anesthetic properties of chloroform were uncovered. Around 1860, in England, the A.C.E. mixture which consisted of 1 part alcohol, 2 parts chloroform and 3 parts ether was preferred over chloroform alone. This mixture was later introduced in Germany where it was used until WW2 (Wawersik J. J Clin Anesth, 1991 3(3) 235–244). Composition of the analyzed vials seems to match this A.C.E. mixture and coherent with historical knowledge. These molecules were administrated by inhalation and it was often regarded as a safe and simple procedure for urgent situations as encountered on the battlefield. For more complex procedures, use of barbiturates was preferred. After WW2, A.C.E. mixture was abandoned in favor of less toxic anesthetics such as nitrous oxide.

Evaluation of Malolactic Starters in White and Rosé Winemaking of Moschofilero Wines

The aim of the present study was to induce malolactic fermentation (MLF) after alcoholic fermentation (AF) of must of the Moschofilero cultivar, the only ‘gris’ native grape variety that is cultivated in Greece. For this purpose, Oenococcus oeni strains Viniflora® CH16, Viniflora® Oenos and Viniflora® CiNe were inoculated after the completion of AF driven by the Saccharomyces cerevisiae strain UCLM S325. Growth of the aforementioned starter cultures was assessed during fermentation by classical microbiological techniques, and verification of their dominance was performed by (GTG)5 fingerprinting. Assessment of standard enological parameters and colorimetric analysis were performed by established approaches. Identification and quantification of organic acids, ethanol and glycerol was performed by high performance liquid chromatography (HPLC), while the solid-phase microextraction method (SPME), coupled with gas chromatography/mass spectrometry (GC/MS), was employed for the identification and quantification of volatile compounds. Finally, sensory analysis took place according to ISO 13299:2016. The suitability of the starter cultures employed to drive AF and MLF was exhibited; AF and MLF of the white and rosé wines were completed after 15 days. Upon completion of AF, substantial differences were observed in the chemical characteristics of the white and rosé wines, which were also reflected in the balance descriptor. MLF also resulted in significant changes. In all cases total acidity decreased and volatile acidity and pH value increased, while the vanilla and butter descriptors increased. Interestingly, the color intensity of the rosé wines also increased. A series of strain-dependent changes in the chemical composition and sensory analysis of both white and rosé wines was also observed.

İran safranı (Crocus sativus L.) ile Türkiye'nin makro ve mikro lokasyonlarda yetiştirilen safranın kalite özelliklerinin karşılaştırılması

In this study, volatile and bioactive compositions of saffron samples collected from Khorasani region in Iran Razavi and different locations in Turkey containing Hatay (Kırıkhan, Iskenderun, Hassa and Yayladağı counties), Karabük (Safranbolu county Yukarıbucak and Ovacuma villages), Ankara (Ayaş, Nallıhan and Polatlı counties), Çukurova region (Adana-Cukurova, Mersin-Tarsus and Osmaniye-Kadirli counties) and Antalya (Korkuteli county) were investigated using gas chromatography-mass spectrometry (GC-MS/FID and GC-MS/MS) for identification and quantification of volatile compounds. Ultrasound-assisted extraction method using methanol:ethyl acetate solvent mixture was used to isolate the volatile components of saffron. This study revealed that the amounts of the volatile and bioactive compounds of saffron veried between different geographical locations. The most important bioactive compounds of saffron, safranal, crocin and crocetin, were also quantitatively analyzed in all saffron samples. The highest amount of safranal and crocin were observed in Hatay yayladağı saffron with 22532.97 mg kg-1 and 647.26 mg/kg, respectively. The highest amount of crocetin was obtained with 6.73 mg/kg in Ankara Ayaş saffron. While Hatay kırıkhan saffron contained the highest fraction of fatty acid content with 23.56%, the highest fraction of bioactive components was discovered in Karabük safranbolu ovacuma saffron with 90.84%. According to the obtained outcomes, the highest qualities saffron were determined to be observed in Hatay yayladağı and Karabük safranbolu ovacuma saffron, respectively.

Mass Spectrometric Quantification of Volatile Compounds Released by Fresh Atlantic Salmon Stored at 4 °C under Modified Atmosphere Packaging and Vacuum Packaging for up to 16 Days

Mass Spectrometric Quantification of Volatile Compounds Released by Fresh Atlantic Salmon Stored at 4 °C under Modified Atmosphere Packaging and Vacuum Packaging for up to 16 Days

Quantification of volatile compounds in “aromatic” and “non-aromatic” strawberry genotypes by means of solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS)

ISHS VII South-Eastern Europe Symposium on Vegetables and Potatoes Quantification of volatile compounds in “aromatic” and “non-aromatic” strawberry genotypes by means of solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS)

Quantification of Volatile Compounds in Wines by HS-SPME-GC/MS: Critical Issues and Use of Multivariate Statistics in Method Optimization

The aim of this review is to explore and discuss the two main aspects related to a HeadSpace Solid Phase Micro-Extraction Gas-Chromatography/Mass-Spectrometry (HS-SPME-GC/MS) quantitative analysis of volatile compounds in wines, both being fundamental to obtain reliable data. In the first section, recent advances in the use of multivariate optimization approaches during the method development step are described with a special focus on factorial designs and response surface methodologies. In the second section, critical aspects related to quantification methods are discussed. Indeed, matrix effects induced by the complexity of the volatile profile and of the non-volatile matrix of wines, potentially differing between diverse wines in a remarkable extent, often require severe assumptions if a reliable quantification is desired. Several approaches offering different levels of data reliability including internal standards, model wine calibration, a stable isotope dilution analysis, matrix-matched calibration and standard addition methods are reported in the literature and are discussed in depth here.

Quantitative determination of volatile compounds using TD-GC-MS and isotope standard addition for application to the heat treatment of food

For many foods that undergo thermal treatment, the generation of numerous process-induced compounds has strong implications for food quality and safety. Today, increasing attention is payed to the generation and occurrence of particular classes of newly formed compounds in processed foods for their potential health implication. It is therefore of the utmost importance to monitor the process with fit-for-purpose methods that are appropriate for use in quality control or in research and innovation. Since many quality-related compounds are volatile, there is a need for robust methods that can quantify a broad range of volatile markers and are applicable to on-line monitoring.To meet this need, an original and reliable method based on thermal desorption has been developed for the quantification of volatile compounds sampled on-line by sorbent tubes. For the first time, this method combines in-tube calibration and deuterated standard addition. Ten volatile compounds that are likely to form during heat processing of food (i.e. baking of cereal products), were chosen as target analytes for their relevance to food quality and their different physicochemical properties: 3-methylbutanal, pyrazine, 2-methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, acetic acid, furfural, 5-methylfurfural, furfuryl alcohol and 5-hydroxymethylfurfural. The key steps in the analytical procedure were optimized and carefully characterized in terms of recovery, repeatability and reliability. The TD-GC-MS method displayed good linearity over extended ranges for all compounds (R2: 0.9950 to 0.8880) with low limits of quantification (LOQs) ranging from 0.0141 to 11.5 ng. The matrix effect was negligible for most compounds, except for 5-hydroxymethylfurfural (21.5%), the most polar and least volatile compound.The method was applied to determining process-induced compounds generated during the baking of a model cake and sampled from baking vapors at three different times during the heat treatment. Of all the compounds extracted, the target analytes exhibited concentrations spread over very broad ranges. This highly sensitive method could therefore be used for the early quantification of relevant markers during the processing of food matrices, for quality or mitigation purposes.Quantitative TD-GC-MS with in-tube calibration and isotope standard addition is particularly well-suited for applications where an accurate determination is required of both trace level and major volatile compounds over time. This method may therefore be relevant for monitoring either industrial or domestic food processes (e.g. baking, frying, roasting), for multi-residue analyses linked to quality and safety, or reaction kinetics for multi-response modeling. It can also be transferable to emerging non-food applications.

Advanced GC–MS method for quality and safety control of alcoholic products

Recently developed and validated simple and reliable quantitative method employing ethanol as an internal standard (IS) for GC–MS quantification of volatile compounds in alcoholic products was applied to 36 samples including commercially available world-famous brand spirits from 18 countries and homemade distillates. The GC–MS analyses were performed simultaneously by the suggested approach and official IS method that is prescribed in the legislation of EU and USA. The independent samples t-test was employed to evaluate the statistical difference between the results of these two methods. The test revealed no difference in the results and their repeatability. The main benefits of the suggested method are the elimination of the necessity of manual IS addition and samples density measurement thus making it more economical and productive.

The perspectives of ethanol usage as an internal standard for the quantification of volatile compounds in alcoholic products by GC-MS.

The potential use of ethanol as an internal standard (IS) for GC-MS analysis was studied. The paper describes the analysis of spirit drinks and other alcoholic products which consist of a mixture of water, ethanol, and volatile compounds. In the suggested method, ethanol was employed as an IS for the common procedure of volatile compounds quantification. A number of standard solutions of nine compounds with different concentrations was prepared in a water-ethanol matrix and measured with GC-MS in the SIM mode. Two possible approaches were suggested to avoid detector saturation during ethanol detection. The first one consisted in using less abundant m/z 47 as quantifiers. These ions mainly correspond to unfragmented heavy ethanol molecules containing one 13 C isotope. The second method consisted in reduction of the voltage of MS electron multiplier. The experiment also included the preparation and subsequent dilution of the standard solution and ethanol with water, which determined the linearity of the modified MS response relative to the ethanol content. Analysis of the obtained results revealed that volatile compounds can be successfully accurately determined with GC-MS by employing ethanol as an IS. Application of the suggested method is not limited to the reported volatile compounds and alcoholic products.