A comparison of solid-phase microextraction (SPME) with simultaneous distillation–extraction (SDE) for the analysis of volatile compounds in heated beef and sheep fats

Organic and conventional alternative curing ingredients effects on quality and sensory attributes of deli-style Turkey

Deli-style turkey breast products were cured with sodium nitrite (SN), pre-converted conventional grown celery (CEL), Swiss Chard (SC), organic grown celery (OCEL), and organic Swiss Chard (OSW) with an ingoing sodium nitrite equivalent of 150 ppm and salt content of 1.60 %. Cured and total meat pigments, total myoglobin content, and salt content were assessed on day 0; color, pH, and residual nitrite were evaluated on days 0, 15, 30, 45, and 60. A 24-h color depletion study was conducted on all treatments (TRTs) after storage (day 15). Consumer panelists were recruited to evaluate sensory attributes of all TRTs. During the storage and light display, SN exhibited the lightest color and the lowest (P < 0.05) levels of yellowness. At 0 h, Celery TRTs demonstrated lower (P < 0.05) hue angle compared to Swiss chard TRTs. This color difference gradually becomes unnoticeable by the conclusion of the test. Furthermore, the choice between organic and non-organic curing does not affect the color of the finished products. Sensory results indicated that OSW exhibited greater earthiness (P < 0.05) than all other TRTs, except for CEL, which showed no significant difference (P > 0.05). Sensory evaluation results also indicated that OSW displayed the greatest non-meat aftertaste (P < 0.001) than all other TRTs and lower bitterness (P = 0.009) than SN. However, regardless of the different plant sources of nitrite (Celery or Swiss Chard) and growing practice of plant powder (conventional or organic), sensory evaluation found that these alternative cures were equivalent (P > 0.05) to SN in overall liking difference and relevant purchase intent. Volatile compounds (VOCs) analysis revealed a distinctively different distribution of VOCs among the different sources of nitrite. The presence of terpene alcohol and lower abundance of aldehydes in OSW could explain the findings identified in the sensory evaluation.

Transcriptome and HS-SPME-GC-MS analysis of key genes and flavor components associated with beef marbling

Wagyu cattle are well-known for their rich marbling. Qinchuan cattle have slower-depositing marbling than Wagyu cattle. However, because of an increase in the consumer demand for high-quality beef and the increasingly stringent standards of beef quality, improving the marbling grade of Qinchuan cattle has become particularly crucial. Therefore, we here considered castrated crossbred Wagyu cattle (crossed with Qinchuan cattle) as the research subjects. Flavor substances in the longissimus dorsi muscle (LDM) of A1 and A5 grades were detected through headspace-solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and electronic nose (E-nose) analysis. Fat deposition-regulating functional genes in both groups were identified through RNA sequencing (RNA-seq) and Weighted gene co-expression network analysis (WGCNA). The results showed that the intramuscular fat (IMF) was significantly higher in A5-grade beef (32.96 ± 1.88) than in A1-grade beef (10.91 ± 1.07) (p < 0.01). In total, 41 and 39 flavor compounds were detected in A1 and A5 grade beef, respectively. Seven aroma compounds were identified base on odor activity values (OAVs) ≥ 1, namely decanal, hexanal, nonanal, heptanol, 1-octen-3-ol, pentanol, and hexanoic acid-methyl ester. Additionally, FABP4, PLIN1, LIPE, ACACA, and CIDEA were the key genes primarily involved in cholesterol metabolism, sterol metabolism, and the PPAR signaling pathway in the two grades of beef. This study attempted to offer comprehensive information on marbling formation-associated candidate genes and gene-enriched pathways, which provides data for future research in beef cattle breeding and beef quality improvement.

Impact of Organic and Conventional Vegetable-Based Curing Ingredients on Frankfurter Quality and Sensory Attributes

Frankfurters, a widely consumed cured meat product in the United States, provide an ideal model for assessing the effects of conventional and organic plant-based curing ingredients. This study aimed to evaluate the impact of commercially available conventional and organic plant-based curing ingredients on the quality and sensory characteristics of frankfurters. Five nitrite source treatments (TRT)s were analyzed: preconverted celery (CEL), organic celery (OCEL), Swiss chard (SW), organic Swiss chard (OSW), and sodium nitrite (SN). Consumer sensory panel scores revealed a subtle variation in the perception of non-meat aftertaste among alternative cured frankfurter TRTs. No difference (p > 0.05) was observed in overall liking and purchase intent among all TRTs. Furthermore, the consumer sensory panel indicated that OSW had a marginally higher (p = 0.077) non-meat aftertaste compared to SW. Analysis of volatile compounds offered detailed insights into the interactions and effects of sodium nitrite and plant-based curing powders on finished products. Esters and terpenoids were strongly positively correlated (r > 0.75) with non-meat aftertaste, whereas alcohols, amino acids, and aldehydes were strongly negatively correlated (r < -0.75) with non-meat aftertaste. This study found that some commercially available organic curing ingredients may go through a deodorization process, resulting in an undetectable non-meat aftertaste. The combined findings indicated that even though non-meat aftertaste is discernible in organic versus conventional cured meat products, it does not affect consumers' overall liking or purchase intent for vegetable-based curing ingredients.

Characterization of Volatilized Compounds in Conventional and Organic Vegetable-Source Alternative Meat-Curing Ingredients

This study investigates the volatile compounds that contribute to the unique flavor and aroma profiles of cured meat products using alternative ingredients, specifically focusing on commercially available, conventional, and organically produced pre-converted celery (Apium graveolens) and Swiss chard (Beta vulgaris subsp. maritima) juices and powders. Volatile compounds were isolated and analyzed using an optimized method involving steam distillation with liquid-liquid phase extraction coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). The key volatile compound identified in celery was 3-butylisobenzofuran-1(3H)-one, and in Swiss chard, 2-methoxy-4-vinylphenol. In both conventional and organic celery juice, senkyunolide, sedanolide, and limonene were the primary volatiles, listed in descending order of concentration. This pioneering work on volatile and aromatic compounds in alternative curing ingredients provides foundational knowledge for sensory and volatile compound studies in alternative meat curing. It also offers valuable insights for organic plant and meat producers, processors, and consumers. Practically, this research highlights volatile chemicals that could interact with other meat constituents or residues in finished products, informing and enlightening future studies on the sensory and aromatic properties of alternative cured meats. Overall, this study contributes to the development of alternative cured meats, supporting the research and innovation of organic meats.

Effective Strategies for Understanding Meat Flavor: A Review

This review provides an effective strategy for understanding meat flavor. Understanding the taste of meat is essential for improving meat quality, and the taste should be analyzed based on complex chemical research to identify various factors that impact the composition, formation, and development of meat. To address flavor chemistry in meat, the discussion focuses on the major compounds responsible for the characteristic flavors of different meats, such as lipids, proteins, and Maillard reaction products. Meat flavor is largely based on heat-induced chemical reactions that convert flavor precursors, such as sugars, proteins, and lipids, into volatile compounds. The flavor of meat is influenced by animal species, sex, age, feed, and processing, and in this respect, flavor is one of the representative quality indicators of meat. Research on meat flavor uses omics technology to study the molecular mechanisms that affect meat quality, including flavor, tenderness, and fat composition. Therefore, this review provides a comprehensive understanding of the complex processes governing meat flavor and provides avenues for further research and industrial applications to advance the meat industry.

Flavor formation based on lipid in meat and meat products: A review

Meat product is popular throughout the world due to its unique taste. Flavor is one of the most important quality characteristics of meat products and also is a key influencing factor in the overall acceptability of meat products. The flavor of meat products is formed by precursors undergoing a series of complex reactions. During meat product processing, lipids are hydrolyzed by lipase to produce flavor precursors such as free fatty acid, then further oxidized to form volatile flavor compounds. This review summarizes lipolysis, lipid oxidation, and interaction of lipid with Maillard reaction and amino acid during meat products processing and storage as well as influencing factors on lipid degradation including raw meat (source of meat, feeding pattern, and castration), processing methods (thermal processing, nonthermal processing, salting, and fermentation) and additives. Meanwhile, the volatile compounds produced by lipids in meat products including aldehydes, alcohols, ketones, and hydrocarbons are summed up. Analytical methods of volatile compounds and the application of lipidomics analysis in mechanisms of flavor formation of meat products are also reviewed. PRACTICAL APPLICATIONS: Flavor is one of the most important quality characteristics of meat products, which influences the acceptability of meat products for consumption. Lipids play an important role in the flavor formation of meat products. Understanding the relationship between flavor compounds and changes in lipid compositions during the processing and storage of meat products will be helpful to control the quality of meat products.

Production of Hydroxy Fatty Acids, Precursors of γ-Hexalactone, Contributes to the Characteristic Sweet Aroma of Beef

Aroma is an essential factor for meat quality. The meat of Japanese Black cattle exhibits fine marbling and a rich and sweet aroma with a characteristic lactone composition. The mechanism of lactone formation associated with beef aroma has not been elucidated. In this study, we examined the precursors of γ-hexalactone, an indicator of the sweet aroma of beef and identified the mechanism underlying γ-hexalactone production. A low-temperature vacuum system was used to prepare beef tallow from Japanese Black cattle and Holstein cattle. The odor components were identified using headspace–gas chromatography. The analysis revealed that γ-hexalactone, γ-dodecalactone, δ-tetradecalactone, and δ-hexadecalactone were present as sweet aroma components of beef tallow prepared from marbling and muscle. Since we previously reported that γ-hexalactone formation correlates with linoleic acid content in beef, we analyzed ten oxidized fatty acids derived from linoleic acid by liquid chromatography–triple quadrupole mass spectrometry and detected two hydroxy-octadecadienoic acids (9S-HODE and 13S-HODE) in beef tallow. Significant differences in arachidonic acid 15-lipoxygenase and cyclooxygenase protein expression levels among subcutaneous fat, intramuscular fat, and muscle tissue were observed. Our results suggest that the combination of linoleic acid and the expression of lipid oxidase derived from beef muscle and intramuscular fat produce hydroxy fatty acids that result in a sweet aroma.

Studies on the Volatiles Composition of Stored Sheep Wool, and Attractancy toward Aedes aegypti Mosquitoes

To discover new natural materials for insect management, commercially available stored sheep wool was investigated for attractancy to female adult Aedes aegypti mosquitoes. The volatiles from sheep wool were collected by various techniques of headspace (HS) extractions and hydrodistillation. These extracts were analyzed using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detector (GC-FID) coupled with GC-MS. Fifty-two volatile compounds were detected, many of them known for their mosquito attractant activity. Seven compounds were not previously reported in sheep products. The volatile composition of the extracts varied significantly across collections, depending on the extraction techniques or types of fibers applied. Two types of bioassay were conducted to study attractancy of the sheep wool volatiles to mosquitoes: laboratory bioassays using glass tubes, and semi-field bioassays using large, screened outdoor cages. In bioassays with glass tubes, the sheep wool hydrodistillate and its main component, thialdine, did not show any significant attractant activity against female adult Ae. aegypti mosquitoes. Semi-field bioassays in two large screened outdoor cages, each equipped with a U.S. Centers for Disease Control (CDC) trap and the various bait setups with Vortex apparatus, revealed that vibrating wool improved mosquito catches compared to the setups without wool or with wool but not vibrating. Sheep wool, when vibrated, may release intensively volatile compounds, which could serve as olfactory cues, and play significant role in making the bait attractive to mosquitoes. Sheep wool is a readily available, affordable, and environment-friendly material. It should have the potential to be used as a mosquito management and surveillance component in dynamic bait setups.

Elucidating the combined effect of sample preparation and solid-phase microextraction conditions on the volatile composition of cooked meat analyzed by capillary gas chromatography coupled with mass spectrometry

Solid-phase microextraction coupled to gas chromatography-mass spectrometry is a common approach to analyze the volatile profile of cooked meat. The present study aims to investigate the combined effect of sample preparation, including meat presentation (minced and steak) and cooking method (stewed and grilled), and extraction temperature (30, 60 and 80 °C) and time (30 and 50 min) on the volatile composition of cooked deer meat. The statistical results indicated that extraction temperature was the most relevant factor affecting the meat volatile profile of cooked meat followed by the extraction time. Higher extraction temperatures improved the detection of heavy volatile compounds, while sample preparation had little influence on the meat volatile profile, probably due to the accurate control of the parameters used for meat presentation and cooking methods. The results of this work can assist in the standardization of analytical procedures for the characterization of volatile compounds in cooked meat.

Physicochemical parameters, fatty acid profile, and sensory attributes of meat from lambs fed with cassava dregs in replacement of corn

The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on physicochemical parameters, fatty acid profile, and sensory attributes of meat. Forty male non-castrated Santa Inês crossbred lambs with an initial average weight of 20 ± 1.87 kg were slaughtered after 70 days. The physicochemical parameters and chemical composition of meat were not affected by the diets. Eicosenoic (C20:1n-9) and linolenic (C18:3n-3) acids increased linearly and there was a linear decreasing effect for the flavor score with increasing cassava dregs in the diets. The replacement of corn by cassava dregs did not influence omega-6:omega-3 ration or the total desirable fatty acids, as well as the color, aroma, tenderness, juiciness, or overall evaluation scores. Cassava dregs may be added in the diets of lambs, without negative effects on physicochemical characteristics, chemical composition, and fatty acid indexes, with positive effects on unsaturated fatty acid content. However, the total replacement of corn altered the sensory attributes and decreased purchase intent of the meat.

Comparison of reducing sugar content, sensory traits, and fatty acids and volatile compound profiles of the longissimus thoracis among Korean cattle, Holsteins, and Angus steers

OBJECTIVE

This study was performed to compare fat content, reducing sugar contents, sensory traits, and fatty acid (FA) and volatile compound profiles in longissimus thoracis (LT) among Korean cattle (KC), Holstein (HO), and Angus (AN) steers.

METHODS

Twelve LT samples (about 500 g each) of KC with an average age of 31±0.42 months, an average carcass weight of 431±12.5 kg, and a quality grade (QG) of 1+ were obtained from the joint livestock products market. Twelve LT samples of HO cattle with an average age of 24±0.54 months, an average carcass weight of 402±7.81 kg, and a QG of 2 were also obtained from the same market. Twelve LT samples of AN steers with an average age of about 20 months and a QG of choice were purchased from a beef delivery company. After slaughter, samples were kept at 4°C for 42 days and prepared for immediate analysis or stored at appropriate conditions. The chemical composition, color, pH, shear force, collagen content, reducing sugars, sensory evaluation, FA composition, and volatile compound content for each LT sample were analyzed.

RESULTS

The LT of KC had the highest (p<0.05) fat content, the highest reducing sugar content, and the highest scores in the sensory evaluation (flavor, tenderness, juiciness, and overall acceptance). All the sensory traits were positively correlated (p<0.001) with intramuscular fat and reducing sugar content. Several FAs and volatile compound profiles varied among the breeds. KC LT had the highest (p<0.05) concentrations of acetaldehyde, 3-methyl butanal, and 3-hydroxy-2-butanone, and these volatile compounds were positively correlated (p<0.05) with all the sensory traits.

CONCLUSION

Variations in fat content and reducing sugar contents and FA and volatile compound profiles may contribute to differences in the sensory quality of LT among breeds.

Discrimination of Aroma Characteristics for Cubeb Berries by Sensomics Approach with Chemometrics

The dried cubeb berries are widely used as medicinal herb and spicy condiment with special flavor. However, there is a significant definition discrepancy for cubeb berries. In this study, an efficient analytical method to characterize and discriminate two popular cubeb fruits (Litsea cubeba and Piper cubeba) was established. The aroma profiles of cubeb berries were evaluated by different extraction methods including hydro-distillation, simultaneous distillation/extraction, and solid-phase micro-extraction followed by gas chromatography-mass spectrometry-olfactometry (GC-MS-O). In total, 90 volatile compounds were identified by HD, SDE, and SPME combined with GC-MS. Principal component analysis was further applied and discriminated ambiguous cubeb berries by their unique aromas: Litsea cubeba was characterized by higher level of d-limonene (“fruit, citrus”), citral (“fruit, lemon”) and dodecanoic acid; α-cubebene (“herb”) was identified as a marker compound for Piper cubeba with higher camphor (“camphoraceous”), and linalool (“flower”). Flavor fingerprint combined with PCA could be applied as a promising method for identification of cubeb fruits and quality control for food and medicinal industries.

Analytical Methods of Phytochemicals from the Genus Gentiana

The genus Gentiana comprises approximately 400 species. Many species have a wide range of pharmacological activities and have been used therapeutically for thousands of years. To provide comprehensive guidance, utilization and quality control of Gentiana species, this review presents updated information concerning the recent application and progress of chemical analysis including phytochemical analysis, sample preparation and chemometrics. Detailed and comprehensive data including number of analytes, extraction/separation methods, analytical techniques and chemometrics are shown as corresponding tables. These data illustrate that the development of newly discovered compounds and therapeutic uses, understanding of the structure-activity relationship and establishment of harmonious and effective medicinal herb standards are the direction of advancement in future research.

Gas-phase chemical ionization of 4-alkyl branched-chain carboxylic acids and 3-methylindole using H3 O+ , NO+ , and O2+ ions

RATIONALE

4-Methyloctanoic acid, 4-ethyloctanoic acid, 4-methylnonanoic acid, and 3-methylindole are primary contributors to the distinctive aroma and flavor of lamb meat. The reactions of H₃ O⁺ , NO⁺ , and O₂⁺ with these compounds, and identification of the product ions and their distribution, are fundamental to their characterization and rapid, real-time trace analysis using selected ion flow tube mass spectrometry (SIFT-MS).

METHODS

The chemical ionization of pure standards of 4-ethyloctanoic acid, 4-methyloctanoic acid, 4-ethylnonanoic acid, and 3-methylindole was carried out using the H₃ O⁺ , NO⁺ , and O₂⁺ reagent ions of a V200™ SIFT mass spectrometer. Kinetic data were calculated using the Langevin collision rate with parameterized trajectory equations. Identification of product ions, distribution, and interferences was performed by further evaluation of the pertinent ion-molecule reaction mechanisms, careful spectral analyses, and molecular mass-molecular structure pairing.

RESULTS

The collisional capture rate constants of the reaction of the precursor ions H₃ O⁺ , NO⁺ , and O₂⁺ , their extended hydrates and the analytes, which were assumed to occur at or near the collisional rate, were all of the order of 10^-9  cm³ molecule s^-1 - typical for bimolecular ion-molecule reactions. Positive identification of the primary and secondary product ions, fragmented ionic species, and potential ion conflicts and interferences, from each reagent ion channel, was determined for each compound.

CONCLUSIONS

We have established the ion chemistry involved in the ionization of the 4-alkyl branched-chain fatty acids and 3-methylindole using the precursor ions, H₃ O⁺ , NO⁺ , and O₂⁺ in SIFT-MS. The ion-molecular chemistry and the associated kinetics serve as a fundamental basis for the accurate characterization of these compounds by SIFT-MS.

Preparation of Optically Active δ-Tri- and δ-Tetradecalactones by a Combination of Novozym 435-catalyzed Enantioselective Methanolysis and Amidation

A combination of Novozym 435-catalyzed methanolysis and amidation using racemic N-methyl-5-acetoxytridecan- and tetradecanamides as a substrate proceeded in good enantioselectivity to afford the corresponding (R)-N-methyl-5-acetoxyalkanamides, (S)-N-methyl-5-hydroxyalkanamides, and (S)-N-cyclohexyl-5-hydroxyalkanamides. Both enantiomers of δ-tri- and δ-tetradecalactones were synthesized in over 90% enantiomeric excesses from the corresponding (R)- or (S)-alkanamides. Addition of cyclohexylamine to Novozym 435-catalyzed methanolysis shortened 24-hour reaction time to reach about 50% conversion. Enantiomers of optically active δ-tri- and δ-tetradecalactones had different odors and thresholds.

Analytical methods for volatile compounds in wheat bread

Bread aroma is one of the main requirements for its acceptance by consumers, since it is one of the first attributes perceived. Sensory analysis, crucial to be correlated with human perception, presents limitations and needs to be complemented with instrumental analysis. Gas chromatography coupled to mass spectrometry is usually selected as the technique to determine bread volatile compounds, although proton-transfer reaction mass spectrometry begins also to be used to monitor aroma processes. Solvent extraction, supercritical fluid extraction and headspace analysis are the main options for the sample treatment. The present review focuses on the different sample treatments and instrumental alternatives reported in the literature to analyse volatile compounds in wheat bread, providing advantages and limitations. Usual parameters employed in these analytical methods are also described.

Determination of Volatile Compounds of Chinese Traditional Aromatic Sunflower Seeds (Helianthus annulus L.)

Chinese aromatic sunflower seeds (ASS) are a traditional snack food of China. During the production process, raw sunflower seeds were boiled by adding several traditional Chinese spices and then roasted to dryness, which lead to the formation of typical aroma, taste and healthful properties of ASS. In this study, volatile compounds from ASS were isolated by static headspace (HS) as well as simultaneous distillation and extraction (SDE) and determined with gas chromatography-mass spectrometry. The results show that the boiling process is necessary to obtain the typical aroma of ASS. A total of 82 compounds were identified, with phenols being the most abundant followed by spice components such as E-anethole and so on. Additionally, an SDE-GC/FID method was established to analyze the quantities of five main volatile compounds with eugenol being the most (16.06–29.30 µg/g). The levels of these five compounds could be used to adjust parameters during production and processing.

The Global Volatile Signature of Veal via Solid-phase Microextraction and Gas Chromatography-mass Spectrometry

The volatile composition of veal has yet to be reported and is one of the important factors determining meat character and quality. To identify the most important aroma compounds in veal from Holstein bull calves fed one of three diets, samples were subjected to solid-phase microextraction (SPME) combined with gas chromatography-quadrupole mass spectrometry (GC-MS). Most of the important odorants were aldehydes and alcohols. For group A (veal calves fed entirely on milk for 90 d before slaughter), the most abundant compound class was the aldehydes (52.231%), while that was alcohols (26.260%) in group C (veal calves fed starter diet for at least 60 d before slaughter). In both classes the absolute percentages of the volatile compounds in veal were different indicating that the veal diet significantly (p<0.05) affected headspace volatile composition in veal as determined by principal component analysis (PCA). Twenty three volatile compounds showed significance by using a partial least-squared discriminate analysis (PLS-DA) (VIP>1). The establishment of the global volatile signature of veal may be a useful tool to define the beef diet that improves the organoleptic characteristics of the meat and consequently impacts both its taste and economic value.

The effects of different extraction methods on composition and storage stability of sturgeon oil

The objective of this study was to assess the effect of different extraction methods on oil yield, colour attributes, oxidative stability, fatty acids composition and production of volatile compounds in sturgeon oil during storage. The supercritical fluid extraction (SFE) method with carbon dioxide resulted in higher oil yields, better colour attributes, and higher oxidative stability compared to other traditional extraction methods such as enzymatic extraction, amino, and wet reduction. After storage at 4 °C for 33 days, the aldehyde content in oil extracted by the enzymatic extraction and wet reduction methods was twice as high as that obtained by the other methods. There was a significant reduction in the content of total acids in oils extracted by the enzymatic extraction and wet reduction methods (p<0.05), whereas amine compounds were mainly detected in oil extracted by the amino method. The oil extracted by SFE exhibited higher UFA and lower SFA. Significant diffidence among PUFA with C above 20 was observed in oil extracted with SFE.

Analysis of Volatile Components ofAdenosma indianum(Lour.) Merr. by Steam Distillation and Headspace Solid-Phase Microextraction

The essential oil ofAdenosma indianum(Lour.) Merr. plays an important role in its antibacterial and antiphlogistic activities. In this work, the volatile components were extracted by steam distillation (SD) and headspace solid-phase microextraction (HS-SPME) and analysed by gas chromatography-mass spectrometry (GC-MS). A total of 49 volatile components were identified by GC-MS, and the major volatile components wereα-limonene (20.59–35.07%), fenchone (15.79–31.81%),α-caryophyllene (6.98–10.32%),β-caryophyllene (6.98–10.19%), and piperitenone oxide (1.96–11.63%). The comparison of the volatile components fromA. indianum(Lour.) Merr. grown in two regions of China was reported. Also, the comparison of the volatile components by SD and HS-SPME was discussed. The results showed that the major volatile components ofA. indianum(Lour.) Merr. from two regions of China were similar but varied with different extraction methods. These results were indicative of the suitability of HS-SPME method for simple, rapid, and solvent-free analysis of the volatile components of the medicinal plants.