Meat Flavor Research Articles

Monosodium Glutamate Perturbs Human Trophoblast Invasion and Differentiation through a Reactive Oxygen Species-Mediated Pathway: An In-Vitro Assessment.

The overproduction of reactive oxygen species (ROS) has been associated with various human diseases. ROS exert a multitude of biological effects with both physiological and pathological consequences. Monosodium glutamate (MSG), a sodium salt of the natural amino acid glutamate, is a flavor-enhancing food additive, which is widely used in Asian cuisine and is an ingredient that brings out the "umami" meat flavor. MSG consumption in rats is associated with ROS generation. Owing to its consumption as part of the fast-food culture and concerns about its possible effects on pregnancy, we aimed to study the impact of MSG on placental trophoblast cells. MSG exposure influenced trophoblast invasion and differentiation, two of the most critical functions during placentation through enhanced production of ROS. Similar findings were also observed on MSG-treated placental explants, as confirmed by elevated Nrf2 levels. Ultrastructural studies revealed signs of subcellular injury by MSG exposure. Mechanistically, MSG-induced oxidative stress with endoplasmic reticulum stress pathways involving Xbp1s and IRE1α was observed. The effect of MSG through an increased ROS production indicates that its long-term exposure might have adverse health effect by compromising key trophoblast functions.

CONSUMER PREFERENCE ANALYSIS AND DEMAND FOR MEAT IN KANO METROPOLIS: A HEDONIC MODEL APPROACH

This study examined consumer preference and demand analysis for meat in Kano metropolis. Primary data were collected through a well-structured questionnaire, a total of one hundred and fifty 158 member of household was selected for this study. It was revealed that majority (72.2%) of consumers earns monthly income of N15, 000-N55, 000. Hedonic regression for meat attributes affecting Price shows that meat flavour (Good) was the reference group while meat with bad flavour was entered as dummy variables and the result shows that meat with good flavour was statistically significant at (P< 0.05) with positive coefficient implying that for any unit increase in these variables, buyers would be willing to pay premium because they showed higher significant buyer preference level, results also shows that meat with good taste was statistically significant at (P< 0.05) with positive coefficient this implying that meat with good taste are point of interest for the consumers and they are ready to pay high premium to buy the commodities with this attributes. It was revealed that amount of fat (high ) was found to be statistically significant with a negative coefficient, implying that meat with low fat is more preferable and are selling at higher prices in the study area. Low income of consumer was the highest constraints associated with meat consumption in the study area, with a mean rank of 3.01, followed by high selling price with the mean rank of 3.63 and food safety with 4.20.

Identification of Key Genes Affecting Flavor Formation in Beijing-You Chicken Meat by Transcriptome and Metabolome Analyses

The flavor of chicken meat is influenced by muscle metabolites and regulatory genes and varies with age. In this study, the metabolomic and transcriptomic data of breast muscle at four developmental stages (days 1, 56, 98, and 120) of Beijing-You chickens (BJYs) were integrated and 310 significantly changed metabolites (SCMs) and 7,225 differentially expressed genes (DEGs) were identified. A Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that SCMs and DEGs were enriched in amino acid, lipid, and inosine monophosphate (IMP) metabolism pathways. Furthermore, genes highly associated with flavor amino acids, lipids, and IMP were identified by a weighted gene co-expression network analysis (WGCNA), including cystathionine β-synthase (CBS), glycine amidinotransferase (GATM), glutamate decarboxylase 2 (GAD2), patatin-like phospholipasedomain containing 6 (PNPLA6), low-specificity L-threonine aldolase (ItaE), and adenylate monophosphate deaminase 1 (AMPD1) genes. A regulatory network related to the accumulation of key flavor components was constructed. In conclusion, this study provides new perspectives regarding the regulatory mechanisms of flavor metabolites in chicken meat during development.

Polymorphism and Association of the Novel KCTD2 Gene with Flavor and Odor in Indonesian Local Sheeps

A candidate marker that influences the flavor and odor of Indonesian sheep that is the Potassium Channel Tetramerization Domain Containing 2 (KCTD2) gene. This study aims to examine the polymorphism and association between the KCTD2 gene and lamb flavor and odor in Indonesian local sheeps. This study used DNA taken from the longissimus dorsi (LD) muscle of 100 rams including 75 Javanese Thin-Tail sheep (JTTS), 10 Javanese Fat-Tail Sheep (JFTS), and 15 Jonggol Sheep (JS), with ranged in weight from 20 to 35 kg and were 10 to 12 months old. The PCR-RFLP technique and GLM test analysis were used to identify polymorphisms and association of KCTD2 gene. The restriction enzyme BafI digests the PCR-RFLP product of the KCTD2 gene. The results showed that the KCTD2 gene was polymorphic (CC and CT). KCTD2 gene analysis showed a significant (P<0.05) association with 3-Methylphenol (MP). This research provide information regarding the role of the KCTD2 gene in lamb flavor and odor, especially in 3-Methylphenol (MP) compounds, and explain KCTD2 as a functional gene in the selection of premium sheep with low flavor and odor in lamb meat.

Effect of feeding on different levels of crushed cactus in total mixed rations on fattening performance, carcass characteristics, and meat quality of Awassi sheep

A ten week feeding experiment was conducted to evaluate the effect of feeding total mixed rations containing different levels of cactus on growth performance, carcass characteristics, and meat quality of Awassi sheep. Twelve lambs with initial body weight of 28.67±2.29 kg and 120 days average age were distributed in complete randomized design into three dietary groups according to crushed cactus level (T1 = 0%, T2 = 10%, and T3 = 15%) in four replicates. At the end of the feeding period three lambs from each dietary group were randomly slaughtered to determine the carcass characteristics and meat quality. The means of the tested parameters were tested for significance using analysis of variance followed by least significant differences at 95% confidence level. Lambs fed T3 diet showed numerically higher (P > 0.05) total weight gain (15.3 kg) and average daily gain (219.1 g). T2 group had numerically higher (P > 0.05) hind quarter perimeter (D), maximum width carcass (Wr), chest depth (Th), and pelvic limb length (F) than T1 and T3. Left half carcass weight (10.5 kg), anterior rib (8.3%), pelvic limb (36.3%), and first quality (66.4%) were numerically higher (P > 0.05) in T2. Results of meat quality presented numerically higher (P > 0.05) water holding capacity (23.7) and lower cooking loss percent (30.6%) in T3, these results were reflected on sensory evaluation as well where T3 recorded significantly higher (P < 0.05) scores in texture and flavor of meat. Therefore, adding crushed cactus up to 15% level in diet of sheep could affect the carcass characteristics and meat quality differently.

Effect of variable pressure-assisted immersion process using (−)-epicatechin on the color, flavor, and polycyclic aromatic hydrocarbons content in roasted beef meat

Polycyclic aromatic hydrocarbons (PAHs) are more easily formed in beef meat than other meats. A previous study confirmed the inhibitory effect of (−)-epicatechin on PAHs in a fat model system. However, (−)-epicatechin solution demonstrates colloidal properties at high concentrations. Hence a variable pressure immersion method was applied to infuse (−)-epicatechin in beef cubes. The fixed variable pressure-assisted immersion process using (−)-epicatechin that ranged from 0.2 mM/L to 5.0 mM/L was found to influence color, flavor, and PAHs dose-dependently. The 0.2 mM/L (−)-epicatechin treatment stabilized color properties, reduced PAHs content, and promoted the formation of volatiles and free amino acids. However, the use of more than 1.0 mM/L (−)-epicatechin, gradually decreased the values of brightness (L*) and yellow to blue color (b*), volatiles and free amino acids content, and reduced the inhibitory effect on PAHs. Therefore, the variable pressure-assisted immersion process of meat in 0.2 mM/L (−)-epicatechin can inhibit PAHs formation without compromising flavor properties of roasted beef.

Long Non-Coding RNA BNIP3 Inhibited the Proliferation of Bovine Intramuscular Preadipocytes via Cell Cycle.

The intramuscular fat (or marbling fat) content is an essential economic trait of beef cattle and improves the flavor and palatability of meat. Several studies have highlighted the correlation between long non-coding RNAs (lncRNAs) and intramuscular fat development; however, the precise molecular mechanism remains unknown. Previously, through a high-throughput sequencing analysis, we found a lncRNA and named it a long non-coding RNA BNIP3 (lncBNIP3). The 5' RACE and 3' RACE explored 1945 bp total length of lncBNIP3, including 1621 bp of 5'RACE, and 464 bp of 3'RACE. The nucleoplasmic separation and FISH results explored the nuclear localization of lncBNIP3. Moreover, the tissue expression of lncBNIP3 was higher in the longissimus dorsi muscle, followed by intramuscular fat. Furthermore, down-regulation of lncBNIP3 increased the 5-Ethynyl-2'- deoxyuridine (EdU)-EdU-positive cells. The flow cytometry results showed that the number of cells in the S phase was significantly higher in preadipocytes transfected with si-lncBNIP3 than in the control group (si-NC). Similarly, CCK8 results showed that the number of cells after transfection of si-lncBNIP3 was significantly higher than in the control group. In addition, the mRNA expressions of proliferative marker genes CyclinB1 (CCNB1) and Proliferating Cell Nuclear Antigen (PCNA) in the si-lncBNIP3 group were significantly higher than in the control group. The Western Blot (WB) results also showed that the protein expression level of PCNA transfection of si-lncBNIP3 was significantly higher than in the control group. Similarly, the enrichment of lncBNIP3 significantly decreased the EdU-positive cells in the bovine preadipocytes. The results of flow cytometry and CCK8 assay also showed that overexpression of lncBNIP3 inhibited the proliferation of bovine preadipocytes. In addition, the overexpression of lncBNIP3 significantly inhibited the mRNA expressions of CCNB1 and PCNA. The WB results showed that the overexpression of lncBNIP3 significantly inhibited the expression of the CCNB1 protein level. To further explore the mechanism of lncBNIP3 on the proliferation of intramuscular preadipocytes, RNA-seq was performed after interference with si-lncBNIP3, and 660 differentially expressed genes (DEGs) were found, including 417 up-regulated DEGs and 243 down-regulated DEGs. The KEGG pathway analysis showed that the cell cycle was the most significant pathway for the functional enrichment of DEGs, followed by the DNA replication pathway. The RT-qPCR quantified the expression of twenty DEGs in the cell cycle. Therefore, we speculated that lncBNIP3 regulated intramuscular preadipocyte proliferation through the cell cycle and DNA replication pathways. To further confirm this hypothesis, the cell cycle inhibitor Ara-C was used to inhibit DNA replication of the S phase in intramuscular preadipocytes. Herein, Ara-C and si-lncBNIP3 were simultaneously added to the preadipocytes, and the CCK8, flow cytometry, and EdU assays were performed. The results showed that the si-lncBNIP3 could rescue the inhibitory effect of Ara-C in the bovine preadipocyte proliferation. In addition, lncBNIP3 could bind to the promoter of cell division control protein 6 (CDC6), and down-regulation of lncBNIP3 promoted the transcription activity and the expression of CDC6. Therefore, the inhibitory effect of lncBNIP3 on cell proliferation might be understood through the cell cycle pathway and CDC6 expression. This study provided a valuable lncRNA with functional roles in intramuscular fat accumulation and revealed new strategies for improving beef quality.

Transcriptome-based analysis of key genes and pathways affecting the linoleic acid content in chickens

Linoleic acid is an essential polyunsaturated fatty acid that cannot be synthesized by humans or animals themselves and can only be obtained externally. The amount of linoleic acid present has an impact on the quality and flavour of meat and indirectly affects consumer preference. However, the molecular mechanisms influencing the deposition of linoleic acid in organisms are not clear. As the molecular mechanisms of linoleic acid deposition are not well understood, to investigate the main effector genes affecting the linoleic acid content, this study aimed to screen for hub genes in slow-type yellow-feathered chickens by transcriptome sequencing (RNA-Seq) and weighted gene coexpression network analysis (WGCNA). We screened for candidate genes associated with the linoleic acid content in slow-type yellow-feathered broilers. A total of 399 Tiannong partridge chickens were slaughtered at 126 days of age, fatty acid levels were measured in pectoral muscle, and pectoral muscle tissue was collected for transcriptome sequencing. Transcriptome sequencing results were combined with phenotypes for WGCNA to screen for candidate genes. KEGG enrichment analysis was also performed on the genes that were significantly enriched in the modules with the highest correlation. A total of 13 310 genes were identified after quality control of transcriptomic data from 399 pectoral muscle tissues. WGCNA was performed, and a total of 26 modules were obtained, eight of which were highly correlated with the linoleic acid content. Four key genes, namely, MDH2, ATP5B, RPL7A and PDGFRA, were screened according to the criteria |GS|>0.2 and |MM|>0.8. The functional enrichment results showed that the genes within the target modules were mainly enriched in metabolic pathways. In this study, a large-sample-size transcriptome analysis revealed that metabolic pathways play an important role in the regulation of the linoleic acid content in Tiannong partridge chickens, and MDH2, ATP5B, RPL7A and PDGFRA were screened as important candidate genes affecting the linoleic acid content. The results of this study provide a theoretical basis for selecting molecular markers and comprehensively understanding the molecular mechanism affecting the linoleic acid content in muscle, providing an important reference for the breeding of slow-type yellow-feathered broiler chickens.

Molecular insights into quality and authentication of sheep meat from proteomics and metabolomics

Sheep meat (encompassing lamb, hogget and mutton) is an important source of animal protein in many countries, with a unique flavour and sensory profile compared to other red meats. Flavour, colour and texture are the key quality attributes contributing to consumer liking of sheep meat. Over the last decades, various factors from ‘farm to fork’, including production system (e.g., age, breed, feeding regimes, sex, pre-slaughter stress, and carcass suspension), post-mortem manipulation and processing (e.g., electrical stimulation, ageing, packaging types, and chilled and frozen storage) have been identified as influencing different aspects of sheep meat quality. However conventional meat-quality assessment tools are not able to elucidate the underlying mechanisms and pathways for quality variations. Advances in broad-based analytical techniques have offered opportunities to obtain deeper insights into the molecular changes of sheep meat which may become biomarkers for specific variations in quality traits and meat authenticity. This review provides an overview on how omics techniques, especially proteomics (including peptidomics) and metabolomics (including lipidomics and volatilomics) are applied to elucidate the variations in sheep meat quality, mainly in loin muscles, focusing on colour, texture and flavour, and as tools for authentication. SignificanceFrom this review, we observed that attempts have been made to utilise proteomics and metabolomics techniques on sheep meat products for elucidating pathways of quality variations due to various factors. For instance, the improvement of colour stability and tenderness could be associated with the changes to glycolysis, energy metabolism and endogenous antioxidant capacity. Several studies identify proteolysis as being important, but potentially conflicting for quality as the enhanced proteolysis improves tenderness and flavour, while reducing colour stability. The use of multiple analytical methods e.g., lipidomics, metabolomics, and volatilomics, detects a wider range of flavour precursors (including both water and lipid soluble compounds) that underlie the possible pathways for sheep meat flavour evolution. The technological advancement in omics (e.g., direct analysis-mass spectrometry) could make analysis of the proteins, lipids and metabolites in sheep meat routine, as well as enhance the confidence in quality determination and molecular-based assurance of meat authenticity.

Characterization of non-volatile and volatile flavor profiles of Coregonus peled meat cooked by different methods

This study investigated the effects of different cooking methods on non-volatile flavor (free amino acids, 5′-nucleotides, and organic acids, etc.) of Coregonus peled meat. The volatile flavor characteristics were also analyzed by electric nose and gas chromatography-ion migration spectrometry (GC-IMS). The results indicated that the content of flavor substances in C. peled meat varied significantly. The electronic tongue results indicated that the richness and umami aftertaste of roasting were significantly greater. The content of sweet free amino acids, 5′-nucleotides, and organic acids was also higher in roasting group. Electronic nose principal component analysis can distinguish C. peled meat cooked (the first two components accounted for 98.50% and 0.97%, respectively). A total of 36 volatile flavor compounds were identified among different groups, including 16 aldehydes, 7 olefine aldehydes, 6 alcohols, 4 ketones, and 3 furans. In general, roasting was recommended and gave more flavor substances in C. peled meat.

Effect of dietary pomegranate by-product on lamb flavour

This study evaluated the effect of the dietary inclusion of whole pomegranate by-product (WPB) on lamb flavour. Seventeen Comisana male lambs (body weight 14.82 kg ± 2 kg) were assigned to 2 treatments. During 36-day feeding trial, the control group (n = 8) received a conventional concentrate diet; the other group (n = 9) received a concentrate diet containing 200 g/kg (dry matter) of WPB, replacing part of barley and corn. After slaughter, fatty acids were determined in raw meat, while volatile organic compounds, SMart nose, and sensory traits were analysed in cooked meat. The concentrations of total polyunsaturated fatty acids, vaccenic and rumenic acid were higher in WPB meat. Most of volatile compounds that arise from lipid degradation (i.e., aldehydes, alcohols, ketones, and hydrocarbons) were found at higher concentrations in the WPB meat than in the control, except for 2-pentanone that was greater in control meat. Although SMart nose clearly discriminated between dietary treatments, consumer panel did not detect differences in meat flavour.

LncPLAAT3-AS Regulates PLAAT3-Mediated Adipocyte Differentiation and Lipogenesis in Pigs through miR-503-5p.

Animal fat deposition has a significant impact on meat flavor and texture. However, the molecular mechanisms of fat deposition are not well understood. LncPLAAT3-AS is a naturally occurring transcript that is abundant in porcine adipose tissue. Here, we focus on the regulatory role of lncPLAAT3-AS in promoting preadipocyte proliferation and adipocyte differentiation. By overexpressing or repressing lncPLAAT3 expression, we found that lncPLAAT3-AS promoted the transcription of its host gene PLAAT3, a regulator of adipocyte differentiation. In addition, we predicted the region of lncPLAAT3-AS that binds to miR-503-5p and showed by dual luciferase assay that lncPLAAT3-AS acts as a sponge to absorb miR-503-5p. Interestingly, miR-503-5p also targets and represses PLAAT3 expression and helps regulate porcine preadipocyte proliferation and differentiation. Taken together, these results show that lncPLAAT3-AS upregulates PLAAT3 expression by absorbing miR-503-5p, suggesting a potential regulatory mechanism based on competing endogenous RNAs. Finally, we explored lncPLAAT3-AS and PLAAT3 expression in adipose tissue and found that both molecules were expressed at significantly higher levels in fatty pig breeds compared to lean pig breeds. In summary, we identified the mechanism by which lncPLAAT3-AS regulates porcine preadipocyte proliferation and differentiation, contributing to our understanding of the molecular mechanisms of lipid deposition in pigs.

Effects of the Expressions and Variants of the CAST Gene on the Fatty Acid Composition of the Longissimus Thoracis Muscle of Grazing Sonid Sheep.

Fatty acid (FA) composition has an important impact on the nutrition and flavor of meat, and on consumer health, and is receiving more attention in the sheep industry. This study aimed to evaluate the relationship between the expression levels of the CAST gene and the FA composition in the longissimus thoracis (LL) muscle, to identify novel variants of CAST, and to perform association analysis with the FA composition in grazing Sonid lambs. The correlation results showed that high expression levels of CAST are correlated with better FA compositions and classes in LL. For association studies, the results showed that c.1210C>T and c.1437G>A in LD-M, and c.2097C>T mutations are associated with some compositions and classes of FA in the LL of grazing Sonid sheep. Two missense c.646G>C (G216R) and c.1210C>T (R404C) mutations were predicted to influence the Calpain_inhib domains of CAST. Thus, the correlation results and associated mutations are expected to be genetic selection markers for the FA composition and meat quality of grazing Sonid lamb muscle and provide new insights into sheep meat quality traits influenced by the ovine CAST gene.

Genome-wide association study for the free amino acid and nucleotide components of breast meat in an F2 crossbred chicken population

Flavor is an important sensory trait of chicken meat. The free amino acid (FAA) and nucleotide (NT) components of meat are major factors affecting meat flavor during the cooking process. As a genetic approach to improve meat flavor, we performed a genome-wide association study (GWAS) to identify the potential candidate genes related to the FAA and NT components of chicken breast meat. Measurements of FAA and NT components were recorded at the age of 10 weeks from 764 and 767 birds, respectively, using a White leghorn and Yeonsan ogye crossbred F2 chicken population. For genotyping, we used 60K Illumina single-nucleotide polymorphism (SNP) chips. We found a total of nine significant SNPs for five FAA traits (arginine, glycine, lysine, threonine content, and the essential FAAs and one NT trait (inosine content), and six significant genomic regions were identified, including three regions shared among the essential FAAs, arginine, and inosine content traits. A list of potential candidate genes in significant genomic regions was detected, including the KCNRG, KCNIP4, HOXA3, THSD7B, and MMUT genes. The essential FAAs had significant gene regions the same as arginine. The genes related to arginine content were involved in nitric oxide metabolism, while the inosine content was possibly affected by insulin activity. Moreover, the threonine content could be related to methylmalonyl-CoA mutase. The genes and SNPs identified in this study might be useful markers in chicken selection and breeding for chicken meat flavor.

Novel plant-based meat alternatives: Implications and opportunities for consumer nutrition and health.

Against the backdrop of the global protein transition needed to remain within planetary boundaries, there is an influx of plant-based meat alternatives that seek to approximate the texture, flavor and/or nutrient profiles of conventional animal meat. These novel plant-based meat alternatives, enabled by advances in food technology, can be fundamentally different from the whole-plant foods from which they are derived. One of the reasons is the necessity to use food additives on various occasions, since consumers' acceptance of plant-based meat products primarily depends on the organoleptic properties. Consequently, a high degree of heterogeneity in formulation and nutritional profiles exists both within and between product categories of plant-based meat alternatives with unknown effects on several aspects of human health. This is further complicated by the differences in digestibility and bioavailability between proteins from animal and plant sources, which have a profound impact on colonic fermentation, nutritional adequacy and potential health effects. On the other hand, emerging strategies provide opportunities to develop affordable, delicious and nutritious plant-based meat alternatives that align with consumer interests.

GC-MS and GC×GC-ToF-MS analysis of roasted / broth flavors produced by Maillard reaction system of cysteine-xylose-glutamate

Maillard reaction products (MRPs) with roasted/broth flavors were prepared and analyzed for the resulting flavor differences. The identification of volatile compounds in MRPs was carried out by GC-MS and GC × GC-ToF-MS. A total of 88 compounds were identified by GC-MS; 130 compounds were identified by GC × GC-ToF-MS, especially acids and ketones were identified. Principal component analysis (PCA) was used to visualize the volatile compounds, and the roasted/broth flavors were differentiated. The contents and types of pyrazines were more in roasted flavors; thiol sulfides and thiophenes were more in broth flavors. All in all, the differences in volatile compounds producing roasted/broth flavors were studied through the cysteine-xylose-glutamate Maillard reaction system, which provided a theoretical basis for the future use of Maillard reaction to simulate meat flavor.

Nutritional Composition, Sensory Quality and Consumer Acceptability of Beef Sausage Fortified With Edible Meat Waste

This study assessed the proximate composition, sensory quality and consumer acceptability of beef sausage fortified with edible meat waste. Lean beef and edible meat waste (EMW) samples were obtained from commercial abattoir and combined in ratio 50:50 and 70:30 and designated as T1 and T2 respectively, while CT contained 90% lean meat and 10% fat. The fresh T1, T2 and CT sausages were thermal processed using microwave and oven-grilling cooking methods. The results showed significant difference in moisture, protein, lipid and ash content of raw and cooked sausages across treatments. Raw sausage fortified with EMW had higher protein and lower lipid contents compared to control treatment (90/10, CT). Cooking of the sausage significantly decreased moisture and increase lipid, protein and lipid content, with microwaved sausage having higher values. The results of sensory quality showed that beef sausage fortified with EMW were all acceptable to consumers, irrespective of the cooking methods used. The distribution of consumers who liked the appearance, colour, texture and flavour of the sausage meat containing EMW were higher than those who dislike the products. Therefore, this study shows that EMW could be successfully used in meat industry to improve quality of sausage during production.

Effect of Different Heat Treatments on the Quality and Flavor Compounds of Black Tibetan Sheep Meat by HS-GC-IMS Coupled with Multivariate Analysis.

There are limited reports about the effect of different heat treatments on the quality and flavor of Black Tibetan sheep meat. The current study examined the effect of pan-frying, deep-frying, baking, and boiling treatment on the quality of Black Tibetan sheep meat; the amino acid, fatty acid, and volatile flavor compounds (VFCs) were investigated by a texture analyzer, ultra-high-performance liquid chromatography (UHPLC), gas chromatography (GC), and headspace-gas chromatography-ion mobility (HS-GC-IMS). The key VFCs were identified through orthogonal partial least squares discrimination analysis (OPLS-DA), and variable importance projection (VIP) values. In addition, Pearson’s correlations between meat quality parameters and key VFCs were examined. The sensory scores, including texture, color, and appearance, of baked and pan-fried meat were higher than those of deep-fried and boiled meat. The protein (40.47%) and amino acid (62.93 µmol/g) contents were the highest in pan-fried meat (p < 0.05). Additionally, it contained the highest amounts of monounsaturated and polyunsaturated fatty acids, such as oleic, linoleic, and α-linolenic acids (p < 0.05). Meanwhile, pan-fried and deep-fried meat had higher amounts of VFCs than baked meat. The OPLS-DA similarity and fingerprinting analyses revealed significant differences between the three heat treatment methods. Aldehydes were the key aroma compounds in pan-fried meat. Importantly, 3-methylbutyraldehyde and 2-heptanone contents were positively correlated with eicosenoic, oleic, isooleic, linoleic, α-Linolenic, and eicosadiene acids (p < 0.05). To sum up, pan-fried Black Tibetan sheep meat had the best edible, nutritional, and flavor quality.

Volatilomic evaluation of protein hydrolysates from free-range chicken bones treated with hot-pressure process

The aim of this study was to develop flavoring agents that can be used in the food industry using protein hydrolysates from free-range chicken bones. The chemical composition of chicken bones was determined and showed high protein and lipid content of 26.27 g/100 g and 12.21 g/100 g, respectively. Enzyme hydrolysis was performed with Flavourzyme® (HF), Alcalase® (HA) and a mixture of both in a 1:1 ratio (HFA). Alcalase® has the highest degree of hydrolysis (20.59%), but the flavoring was then prepared with the Flavourzyme® hydrolysate because the volatiles are present in greater quantity and quality for meat flavor. Finally, glucose or xylose was added to the hydrolysates to obtain the flavorings GF and XF. It was found that XF had a higher browning intensity (Maillard reaction) with luminosity values (L*) ranging from 74.24 to 65.17, and the XF flavoring contained eight more aldehydes than the GF flavoring. Thus, the flavoring made with protein hydrolysate of free-range chicken bones added with xylose showed the aromatic potential of meat and can be used as an ingredient in the food industry.

Profiles of muscular amino acids, fatty acids, and metabolites in Shaziling pigs of different ages and relation to meat quality.

Pork meat is closely related to physicochemical alterations during growth and development, resulting in differences in nutritional value and meat flavor. This study aimed to evaluate the composition of amino acids, fatty acids, and metabolic profiles in the longissimus thoracis muscle (LM) of Shaziling pigs aged 30, 90, 150, 210, and 300 days. The results showed that the predominant fatty acids identified in the LM of Shaziling pigs were C16:0, C16:1, C18:0, C18:1n9c, and C18:2n6c. An opposite correlation was observed for C18:2n6c and n6/n3 polyunsaturated fatty acids (P<0.05). Alanine, aspartate, glutamate, D-glutamine, and D-glutamate metabolism were the main metabolic pathways for the Shaziling pig meat flavor (P<0.05). Moreover, the correlation coefficients revealed that the contents of anserine, C16:0, C16:1, and C18:1n9c were positively correlated with intramuscular fat and/or pH24h and were negatively correlated with the values of L* (lightness) and b* (yellowness) (P<0.05). In conclusion, age greatly affected the meat quality of Shaziling pigs, and the contents of muscular anserine, C16:0, C16:1, and C18:1n9c might be promising indicators for better meat quality.