Comparison and characterization of volatile compounds as markers of oils stability during frying by HS–SPME-GC/MS and Chemometric analysis

Effect of amino acids on the formation and distribution of volatile aldehydes in high oleic sunflower oil during frying

This research aims to assess the effect of amino acids as lipid antioxidants in reducing the formation of volatile aldehydes in frying oil. Methionine, histidine, and glycine at concentrations of 2.5, 5, and 10 mM were added to high oleic sunflower oil (HOSO) to investigate their effects on the distribution and formation of saturated, monounsaturated, and polyunsaturated volatile aldehydes. The results showed that the proportion of saturated volatile aldehydes was greater than that of unsaturated ones; Methionine exhibited the best inhibitory effect, after 12 h of frying, 10 mM methionine reduced the content of saturated volatile aldehydes by 24.21 %, monounsaturated by 52.4 %, and polyunsaturated by 54.73 % compared to the control. Methionine's sulfur-containing side chain was also proven to have strong antioxidant activity. Combined with the results of this study, this can also provide insights for using amino acids as lipid antioxidants.

Potential of polyphenols from Ligustrum robustum (Rxob.) Blume on enhancing the quality of starchy food during frying

The increasing concerns about health have led to a growing demand for high-quality fried foods. The potential uses of Ligustrum robustum (Rxob.) Blume, a traditional tea in China, as natural additives to enhance the quality of starchy food during frying was studied. Results indicated that L. robustum polyphenols extract (LREs) could improve the quality of fried starchy food, according to the tests of color, moisture content, oil content, texture property, and volatile flavor. The in vitro digestion results demonstrated that LRE reduced the final glucose content from 11.35 ± 0.17 to 10.80 ± 0.70 mmol/L and increased the phenolic content of fried starch foods from 1.23 ± 0.04 to 3.76 ± 0.14 mg/g. The appearance and polarizing microscopy results showed that LRE promoted large starch bulges on the surface of fried starchy foods. Meanwhile, X-ray diffraction results showed that LRE increased the intensity of characteristic diffraction peak of fried starch with a range of 21.8%-28%, and Fourier transform infrared results showed that LRE reduced the damage to short-range order structure of starch caused by the frying process. In addition, LRE increased the aggregation of starch granules according to the SEM observation and decreased the enthalpy of starch gelatinization based on the differential scanning calorimetry results. The present results suggest that LREs have the potential to be utilized as a natural additive for regulating the quality of fried starchy food in food industries. PRACTICAL APPLICATION: The enhancement of L. robustum polyphenols on the quality of starchy food during frying was found, and its mechanisms were also explored. This work indicated that L. robustum might be used as a novel economic natural additive for producing high-quality fried foods.

Effect of Different Vegetable Oils on the Flavor of Fried Green Onion (Allium fistulosum L.) Oil

The flavor of fried green onion oil (Allium fistulosum L.) is widely applied and popular in Chinese cuisine. This work aimed to explore the effects of different varieties of vegetable oils on the flavor profile generation of fried green onion oil. The volatile flavor components of seven different kinds of fried green onion oils, i.e., soybean oil, palm oil, olive oil, corn oil, sunflower oil, camellia oil, and colza oil, were identified and analyzed by sensory analysis, gas chromatography–mass spectrometry (GC-MS) and electronic nose. The results showed that sensory analysis and electronic nose were accepted to detect the odor diversities of different kinds of fried green onion oil sensitively. A total of 103 volatile flavor components were identified positively, and the key aromas included aldehydes and sulfur-containing compounds that correlated highly with green grass, oily, pungent and shallot scent attributes. Meanwhile, fatty acid compositions showed that there were no significant changes in the types of fatty acids before and after frying, but the relative content was not different. Accordingly, the unsaturated fatty acids (UFA, C18:1, C18:2, C18:3, and C20:1) had a significant influence on the flavor of frying oil, which was peculiarly prone to oxidation and heat degradation reactions. These results provided a theoretical basis for further application of fried onion flavor in the food industry.

Elucidation of decomposition pathways of linoleic acid hydroperoxide isomers by GC-MS and LC-MS/MS

Food lipid oxidation provides various volatile compounds involved in food flavor via the decomposition of lipid hydroperoxide (LOOH). This study predicted the pathways which can coherently explain LOOH decomposition focusing on hydroperoxy octadecadienoic acid (HpODE) isomers (9-EZ-HpODE, 9-EE-HpODE, 10-HpODE, 12-HpODE, 13-ZE-HpODE, and 13-EE-HpODE) which are the major LOOH contained in edible oils. Each standard was first prepared and thermally decomposed. Generated volatile and non-volatile compounds were analyzed by GC-MS and LC-MS/MS. The results showed that all HpODE decomposition was based on the factors such as favorable scission, radical delocalization, and cyclization. Interestingly, the formation of 8-HpODE and 14-HpODE were demonstrated during HpODE decomposition. The insights obtained in this study would explain the generation pathways of flavor involved in food quality.

Process Modelling and Simulation of Key Volatile Compounds of Maillard Reaction Products Derived from Beef Tallow Residue Hydrolysate Based on Proxy Models

The hydrolysis time is directly related to the flavor of the Maillard reaction, but existing proxy models cannot simulate and model the variation curves of vital volatile components. This study developed a predictive model for modelling and simulating key volatile compounds of Maillard reaction products (MRPs) derived from beef tallow residue hydrolysate. Results showed the degree of hydrolysis increased with hydrolysis time, and the most significant improvement in the roast flavor and overall acceptance was when hydrolyzing 4 h. Based on flavor dilution value and the relative odor activity value, nine key volatile components were identified, and 2-ethyl-3,5-dimethylpyrazine with roast flavor was the highest. Compared with Polynomial Curve Fitting (PCF) and Cubic Spline Interpolation (CSI), key volatile compounds of MRPs could be better modeled and simulated by the Curve Prediction Model (CPM). All results suggested that CPM could predict the changes in key volatile components produced by MRPs.

Effects of Ligustrum robustum (Rxob.) Blume extract on the quality of peanut and palm oils during storage and frying process

The potential uses of Ligustrum robustum (Rxob.) Blume extract as a natural antioxidant to protect the quality of different oils during storage and frying process were studied. The results showed that L. robustum extract has been shown to retard the decline in the quality of both oils based on the tests of acid value, peroxide value, p-anisidine value, color, volatile flavor, and fatty acid compositions, and the protective effect of L. robustum extract on the quality of peanut oil was better than that of palm oil. By the component analysis, L. robustum extract was found to have a total phenols content of 140.75 ± 1.52 mg/g, and ligurobustoside C was identified as the main phenolic compound. The thermogravimetric and differential scanning calorimetry results showed that L. robustum extract enhanced the oxidative stability of peanut and palm oils. In addition, Fourier transform infrared results indicated that L. robustum extract had protective effects on the C=C bond and ester bond of oil molecule. Moreover, by using electron spin resonance technique, L. robustum extract showed the ability to inhibit and scavenge alkyl-free radicals in both oils. The present results suggested that L. robustum extract may protect the quality of oils during the storage and frying process by inhibiting the oxidation of unsaturated fatty acids and might be a potential natural antioxidant in the food industry. PRACTICAL APPLICATIONS: The excellent antioxidant ability of Ligustrum robustum (Rxob.) Blume extract on the oxidation of different oils and its low price indicated that it could be used as a new low-cost natural antioxidant in oil processing.

An Evaluation Model for the Quality of Frying Oil Using Key Aldehyde Detected by HS-GC/MS

To establish a practical model for evaluating the oxidation of frying oil using aldehydes, the aldehydes of 10 commercial oils during frying at 180 °C were identified using headspace-gas chromatography/mass spectrometry, and the changes of common aldehydes and their correlation with carbonyl values (CV) were analyzed. The results showed that the total peak area of aldehydes increased significantly with heating time, which was related to the fatty acid and tocopherol contents of the oils. There were four common aldehydes with different trends during frying, namely, pentanal, hexanal, (E)-hept-2-enal, and nonanal. Moreover, pentanal with a high correlation with CV was selected as the quality evaluating index of frying oil due to its stable accumulation over time. Based on the linear fitting relationships between CV and pentanal, as well as the initial content ratio of linoleic acid to palmitic acid and total tocopherols in oils, a predictive model was established for evaluating the quality of frying oils with high precision and non-reagent by using mass spectrometry. In summary, this work provides theoretical support for using aldehyde as the quality evaluation index of frying oil and provides a new idea for evaluating oil deterioration from the perspective of volatile compounds.

Enhancement of Oxidative Stability of Perilla Seed Oil by Blending It with Other Vegetable Oils

Perilla seed oil is mainly composed of omega-3 fatty acid (α-linolenic acid, ALA). Despite being nutritionally favorable and rich in unsaturated fatty acids, its low oxidative stability limits its application in food. Thus, the present study aimed to formulate a stable oil blend using perilla seed oil with selected vegetable oil of higher stability characteristics and balance the ratio of the fatty acids. Hence, improving the nutritional and functional value of the blended oil. Perilla seed oil was blended with different edible oil (palm olein, coconut oil, and groundnut oil) in ratios of 20:80 and 30:70. All the blended oils were studied for their fatty acid composition, physicochemical properties, oxidative stability, and nutritional quality index. It was found that perilla seed oil blended with saturated oil like palm olein had improved physicochemical properties and oxidative stability (0.5 h to 6.5 h). The fatty acids ratio of perilla and palm olein blends was close to the recommended value given by the World health organization (WHO). The nutritional quality indices (atherogenic index, the thrombogenic index, and hypocholesterolemic: hypercholesterolemic ratio) of blended oil were also improved compared to the individual oils.

Analysis of the volatile compounds in Fuliji roast chicken during processing and storage based on GC-IMS

To investigate the flavor changes of Fuliji roast chicken during processing and storage, the volatile organic compounds (VOCs) during processing (fresh, fried, stewed and sterilized) and storage (1 month, 2 months and 4 months) were determined by gas chromatography ion mobility spectrometry (GC-IMS). A total of 47 kinds of VOCs were identified across seven sampling stages, including aldehydes, hydrocarbons, alcohols, ketones, esters, ethers and heterocyclic compounds. More diverse range of aldehydes, alcohols, ketones and esters have been detected compared to acids, ethers and heterocyclic substances. Fingerprints directly reflect the pattern of VOCs at different stages of growth and decay, revealing that frying and stewing are key processes in flavor formation, and that sterilization and storage processes lead to flavor loss in Fuliji roast chicken. Hexanal, nonanal, octanal, 2-heptanone, 3-octanol, 1-octene-3-alcohol, 1-pentanol and ethyl acetate were mainly generated during the frying process. Benzaldehyde, nonanal, octanal, methyl-5-hepten-2-one, 2-methyl-3-heptanone, 1,8-Cineole, linalool, butyl acetate, ethyl propionate, ethyl acetate, coumarin, 2-furfuryl methyl disulfide and 2-pentyl furan were mainly generated during the stewing process. After sterilization, the content of octanal-D, 2-heptanone-D, 2-Methyl-3-heptanone, pentan-1-ol-D decreased, resulting in the reduction of aroma, lemon flavor and oil flavor of Fuliji roast chicken. Seven flavor markers, including hexanal-D, nonanal-M, octanal-M, heptanal-D, acetone, 3-octanol and ethyl acetate-D, were identified in the evolution of the aroma profile of Fuliji roast chicken.

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GC-IMS profiles of flavor components in poultry product processing line.

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47 kinds of volatile substances were identified by GC-IMS.

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Frying and stewing were the key processes of flavor formation.

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Flavor markers in the evolution of aroma characteristics of Fuliji roast chicken were determined.

DCMC as a Promising Alternative to Bentonite in White Wine Stabilization. Impact on Protein Stability and Wine Aromatic Fraction

Protein haze in white wine is one of the most common non-microbial defects of commercial wines, with bentonite being the main solution utilized by the winemaking industry to tackle this problem. Bentonite presents some serious disadvantages, and several alternatives have been proposed. Here, an alternative based on a new cellulose derivative (dicarboxymethyl cellulose, DCMC) is proposed. To determine the efficiency of DCMC as a bentonite alternative, three monovarietal wines were characterized, and their protein instability and content determined by a heat stability test (HST) and the Bradford method, respectively. The wines were treated with DCMC to achieve stable wines, as shown by the HST, and the efficacy of the treatments was assessed by determining, before and after treatment, the wine content in protein, phenolic compounds, sodium, calcium, and volatile organic compounds (VOCs) as well as the wine pH. DCMC applied at dosages such as those commonly employed for bentonite was able to reduce the protein content in all tested wines and to stabilize all but the Moscatel de Setúbal varietal wine. In general, DCMC was shown to induce lower changes in the wine pH and phenolic content than bentonite, reducing the wine calcium content. Regarding which VOCs are concerned, DCMC produced a general impact similar to that of bentonite, with differences depending on wine variety. The results obtained suggest that DCMC can be a sustainable alternative to bentonite in protein white wine stabilization.

Influence of Oil Types and Prolonged Frying Time on the Volatile Compounds and Sensory Properties of French Fries

In order to study the flavor of French fries (FFs) prepared in different frying oils, we identified and compared the volatiles of FFs fried in high-oleic sunflower oil (HSO), sunflower oil (SO), linseed oil (LO), and palm oil (PO) during prolonged 24 h frying time. 47 different kinds of volatiles were presented, and aldehydes were the most abundant compounds. The FFs prepared in SO were rich in alkadienals, especially the (E, E)-2,4-decadienal, thus inducing the highest deep-fried odor. The content of alkenals was higher in FFs prepared in HSO, among which (E)-2-nonenal and 2-undecenal provided the undesirable oily flavor. Whereas, FFs prepared in PO were rich in alkanals, and showed an undesirable green aroma because of hexanal. Besides, the aldehydes in FFs fried in LO were the least with more undesirable flavor substances (e.g. (E, E)-2,4-heptadienal). In addition, except for the FFs fried in LO, the aldehydes in other FFs showed an increasing trend. While, the volatiles from the Maillard reaction (e.g. pyrazines) showed no clear pattern. Meanwhile, frying process had optimum frying window (approximately 12 h with total polar compounds content of 14.5%-22.2% in different oils), and the French fries prepared in this period obtained higher flavor score. Therefore, the comparison related to volatiles of FFs provided a basis for the flavor control to a certain extent.

New vacuum cooking techniques with extra-virgin olive oil show a better phytochemical profile than traditional cooking methods: A foodomics study

In this work, the major changes in extra-virgin olive oil (EVOO) composition during cooking were assessed. A foodomics approach based on both metabolomics and lipidomics was used to evaluate the impact of six different cooking techniques, three traditional and three more innovative (Crock-pot®, Roner® and Gastrovac®), and the effect of temperature and cooking time. The lipophilic and hydrophilic fractions of EVOO that underwent different cooking processes were characterized by untargeted high-resolution mass spectrometry approaches. Multivariate statistics were used to unravel the differences in chemical signatures. The different cooking methods resulted in broadly different phytochemical profiles, arising from thermally driven reactions accounting for hydrolysis, synthesis, and oxidation processes. The innovative cooking techniques marginally altered the phytochemical profile of EVOO, whereas sauteing was the cooking method determining the most distinctive profile. Conventional cooking methods (oven, pan-frying, and deep-frying) produced more oxidation products (epoxy- and hydroxy-derivatives of lipids) and markedly induced degradation processes.

Oxidative stability of high oleic sunflower oil during deep-frying process of purple potato Purple Majesty

The behaviour of high oleic sunflower oil in deep frying process of purple potato Purple Majesty has been evaluated simulating a fast food cooking process. This oil was used for 8h/day for 6 days, filling up from the 2nd day. A discontinuous and prolonged procedure was tested. Free Fatty Acidity (FFA), Peroxide Value (PV), Total Polar Compounds (TPC), Fatty Acid (FA) composition, Volatile Organic Compounds (VOC) have been determined at different times in thermo-oxidized (T-OX) oil, and in frying oil. The FFA in T-OX oil samples showed values in the range 0.09%–0.24%, whereas in the frying oil values varied in a range between 0.09% and 0.16%. TPCs values varied from 1.76% to 38.24% in T-OX oils, whereas in frying oil used for frying purple potatoes (FOPP) showed values in the range from 1.76 to 29.13%. The peroxides values did not follow a regular pattern, both during thermo-oxidation and during frying. Among the Long Chain Fatty Acids (LCFAs), oleic acid was the most represented (84.13%). Short chain fatty acids (SCFAs) amount was 0.34% (octanoic acid). Medium chain fatty acids (MCFA) amount was 4.45% (palmitic acid). During the thermo-oxidation, the poly-unsaturated fatty acids (PUFA) amount decreased during the 48 h of heat treatment, reaching an amount of 6.21%. This determined the increase in short chain fatty acids (SCFA). Trans fatty acids increased with the frying time. Unsaturated fatty acids (UFA) reached the value of 90.19%; SFA was 9.79%, and octanoic acid was 0.20%. A correlation between TPC vs UFA/SFA and TPC vs C18:2/C16:0 was observed in the frying oil. The most abundant volatile compounds in frying oil (from 0 to 48 h) were the aldehydes produced by decomposition of hydroperoxides of oleic and linoleic acids.

Quantitation of volatile aldehydes using chemoselective response dyes combined with multivariable data analysis

Current work proposed a novel quantitative method of volatile aldehydes (VAs) using chemoselective response dyes (CRDs) combined with multivariate data analysis. Multivariate spectral data of selected CRDs was obtained by visible near-infrared spectroscopy. The Synergy-interval Partial Least Squares (Si-PLS) algorithm processed multivariate spectral data to establish VAs quantitative prediction models at the level of 0.0002 v/v to 0.18 v/v. The prediction coefficient (Rp) values of models ranged from 0.8399 to 0.9886, and the Root Mean Square Error of Prediction (RMSEP) values were less than 0.01. These models were verified by classification of aging rice samples, and 93% samples were correctly identified in prediction set. In addition, Density Functional Theory (DFT) calculations explored the interaction mechanism between selected CRDs and VAs. The optimized Highest Occupied Molecular Orbital-Lowest Unoccupied Molecular Orbital (HOMO-LUMO) energy levels, dipole moment, distance between molecules were found to have strong correlations with the interaction.

Revealing the yeast modulation potential on amino acid composition and volatile profile of Arinto white wines by a combined chromatographic-based approach

The importance of yeasts in aroma production during wine fermentation is a significant concern for obtaining a wine that appraises a broad number of consumers. For wine producers, wine aroma modulation is an essential issue where the yeasts used during the winemaking process represents a feasible way to improve the complexity and enhance wines specific characteristics. During the fermentation process of wines, yeasts convert grapes sugars into alcohol, carbon dioxide and a large number of secondary metabolites, depending on yeast metabolism, affecting the wine composition, namely its aroma and amino acids (AAs) composition. So, the present work aims to study the effect of different Saccharomyces-type yeasts on the AAs composition and volatile profile of Arinto white wines. To pursue this goal, four white wines from Arinto grapes were fermented with three different commercial yeasts (Saccharomyces bayanus EC1118, Saccharomyces cerevisiae CY3079, Saccharomyces bayanus QA23) and one Native yeast. Arinto wines AAs composition was quantified by HPLC-DAD, after a derivatization step to obtain the aminoenone derivatives. The volatile content of Arinto wines was determined by GC/MS, after an HS-SPME extraction. Results showed significant differences among the AAs content and volatile profile in the Arinto wines. The higher AAs content was found in the Arinto wines fermented with the CY3079 yeast (470.74 mg•L^-1), and the lowest content of AAs in the Arinto wines fermented with EC1118 yeast (343.06 mg•L^-1). Native yeast results in wines with a volatile profile richer in esters compared to the other sample wines. Principal component analysis (PCA) obtained with combined data of AAs and volatile compounds, after normalization, for each Arinto wine samples, shows a clear separation of wines fermented with Native and CY3079 yeasts in relation to QA23 and EC1118 fermented wines . The first and second principal components are responsible for 44.40% and 32.20%, respectively, of the system's variance, which clearly showed a differentiation among wines.

RP-UHPLC-DAD-QTOF-MS As a Powerful Tool of Oleuropein and Ligstroside Characterization in Olive-Leaf Extract and Their Contribution to the Improved Performance of Refined Olive-Pomace Oil during Heating

Since olive leaf is a potential source of phenolic fraction that is assumed to have good antioxidative effects, we purposed to add its extract to the refined olive-pomace oil during heating to increase its oxidative stability. RP-UHPLC-DAD-QTOF-MS was employed to characterize the phenolic fraction.The oil samples were evaluated by measuring the polymers and the polar compounds and thus detecting specific oxidized compounds. Using this approach, the results showed that incorporating olive leaf extract in refined oil significantly reduced the formation of polymers from 14.39% to 10.45% and the oxidation state by the variation of extinction ΔK from 3.02 to 2.29 during 20 h of heating compared to unenriched oil. This study has proven that the use of natural substances is an opportunity to extend the life of refined oils.

Caracterización de los compuestos de aroma del aceite de sacha inchi (Plukenetia volubilis L.) por HS-SPME-GC-MS-O

Se identificaron los componentes aromáticos activos provenientes de muestras comerciales del aceite de sacha inchi, obtenidos de cultivos de Santa Rosa de Osos (Antioquia, Colombia), mediante la técnica de microextracción en fase sólida acoplada a cromatografía de gases, espectrometría de masas y olfatometría (HS-SPME-GC-MS-O). En la optimización de la técnica de extracción se definieron las siguientes condiciones: fibra de SPME de divinilbenceno/ carboxen/polidimetilsiloxano (DVB/CAR/PDMS), temperatura de extracción de 50 °C y tiempo de exposición de 40 min. Bajo estas condiciones, se encontraron un total de 20 compuestos aromáticos activos, donde se destacan el E-2-octenal, E-heptanal, (E,E)-3,5-octadien-2-ona, ácido hexanóico y (E,E)-2,4-heptadienal como los componentes con mayor aporte a la formación del aroma del aceite de sacha inchi.

Scavenging of Acrolein by Food-Grade Antioxidant Propyl Gallate in a Model Reaction System and Cakes

Reactive carbonyl species (RCS), such as acrolein (ACR), glyoxal (GO), and methylglyoxal (MGO), have received extensive attention recently as a result of their high activity and toxicity in vitro and in vivo. In the present study, propyl gallate (PG), a common food antioxidant, was found to effectively trap more ACR than butylated hydroxytoluene and butylated hydroxyanisole through the formation of mono-ACR adducts (PG-ACR) and di-ACR adducts (PG-2ACR). The two adducts were successfully purified, and their structures were elucidated on the basis of their high-resolution mass spectrometry and ¹H, ¹³C, and two-dimensional nuclear magnetic resonance data. We further identified that PG-ACR had the ability to continue to trap GO and MGO to form PG-ACR-GO and PG-ACR-MGO, respectively, by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Furthermore, we verified that PG could inhibit the production of ACR, GO, and MGO via trapping these RCS simultaneously to form the corresponding adducts in pound cakes using LC-MS/MS.

Flavor formation in frying process of green onion (Allium fistulosum L.) deep-fried oil

Fried allium oil has been widely used in traditional Chinese home cooking and recently has grown in popularity in the food manufacturing industry. Thus, physical and chemical changes during frying process were measured to investigate the flavor formation mechanism in green onion (Allium fistulosum L.) deep-fried oil. With the increase of the oil temperature, important variations took place when the temperature rose above 140 °C during the whole frying process. A detailed study of these changes was made from both macro and micro aspects. From a macro perspective, sensory attributes including burnt, fried, oily, cooked vegetable and salty were strengthened. Meanwhile, the reference points of the oil samples on the fingerprint chart were distinguishable from others by electronic nose. In addition, contents of furans and furanones, sulfur-containing compounds, aldehydes and alcohols increased sharply according to SAFE-GC-MS analysis from a microscopic point of view, and contents of unsaturated fatty acids dropped remarkably while the saturated ones increased. These changes were considered to be caused by interactions between carbohydrates, proteins and fats in the deep-fried system and thermo degradations of sugars, amino acids and fats. The results indicated that the stage, when frying at temperatures ranging from 140 °C to 165 °C, was the most significant period for the flavor formation of the deep-fried oil.

Comparison of volatile compounds released by entomopathogenic fungi

Entomopathogenic fungi are fungal species which are used as a potential source of biopesticides. These fungi produce secondary metabolites which in insects can cause disruption in the normal functioning of their bodies, disease or even death. In order to fully characterize the physiology of entomopathogenic fungi we should identify the volatile organic compounds which are involved in this process. Therefore, we conducted a qualitative and quantitative analysis of volatile compounds produced by entomopathogenic fungi. Seven different species of fungi were analyzed: Metarhizium anisopliae, Metarhizium flavoviride, Pandora sp., Isaria fumosorosea, Hirsutella danubiensis, Batkoa sp. and Beauveria bassiana. The analyses were performed using the HS-SPME/GCMS technique. In the analyzed fungi, 63 volatile compounds were identified and classified into the following groups: aldehydes, ketones, alcohols, esters, acids, terpenes and others. The results show that entomopathogenic fungi produce a wide profile of secondary metabolites. Principal Components Analysis was used to determine whether separate classes of fungi can be distinguished from one another based on their metabolite profiles.