Changes in physico-chemical properties and volatile compounds throughout the manufacturing process of dry-cured foal loin

Lipid degradation contributes to flavor formation during air-dried camel jerky processing

Lipids play an important role in flavor formation in meat products. To determine the contribution of lipids to flavor formation during air-dried camel jerky processing, lipid changes were analyzed by UHPLC-Q-Exactive Orbitrap MS/MS in this study, and volatile compounds were identified by HS-SPME-GC-ToF-MS. Results showed that 606 lipid molecules belonging to 30 subclasses were identified and 206 differential lipid molecules were screened out (VIP > 1, P < 0.05); Cer/NS (d18:1/20:0), LPE (18:1), FA (18:0), GlcADG (12:0/24:1), and PE (18:2e/22:5) were identified as potential lipid biomarkers. A total of 96 volatile compounds were also identified, and 16 of these were identified as key aroma compounds in air-dried camel jerky. Meanwhile, 11 differential lipids significantly, negatively correlated with 7 key aroma compounds (P < 0.05) during processing, indicating that the precursors produced by the degradation of lipid molecules were important sources of volatile flavor substances in air-dried camel jerky.

Changes in protein and volatile flavor compounds of low-salt wet-marinated fermented Golden Pomfret during processing

In this experiment, the changes in protein hydrolysis, protein oxidation, and flavor of low-salt wet-marinated fermented golden pomfret were studied during processing. During processing, a decrease in sulfhydryl content (P < 0.05), a significant increase in protein surface hydrophobicity (P < 0.05), a significant increase in carbonyl content and TCA-soluble peptide (P < 0.05), an increase in TVB-N and amino acid nitrogen (P < 0.05), and a significant increase in the content of free amino acids (P < 0.05), indicating that proteins were gradually oxidized and degraded to small molecules and flavor precursors under the action of bacterial reduction pretreatment, deodorization, marination and fermentation processes, small molecules and aroma precursors was generated by gradual oxidative decomposition. In the course of processing, a total of 113 volatile flavor compounds were identified using GC-MS analysis, while OPLS-DA analysis and VIP value determination led to the identification of 10 characteristic flavor compounds. The results showed that an abundance of flavor compounds was generated during the processing, thereby imparting a more pronounced taste profile to the low-salt wet-marinated fermented golden carp. The results showed that a large number of flavor substances were generated during the processing to give a richer flavor to low-salt wet-marinated fermented golden pomfret that could provide data and theoretical support for the subsequent processing industry of golden pomfret.

Incorporating Olive By-Products in Bísaro Pig Diets: Effect on Dry-Cured Product Quality

The objective of this study was to assess the impact of incorporating olive cake into the diet of indigenous Bísaro pigs on the quality of processed meat products. To this end, loins and "cachaços" were processed using a standardized manufacturing flowchart to produce dry-cured products. The two products were manufactured using the same formulation, ingredients, and curing process. Concerning the physicochemical composition, there were significant differences between the two products for the parameters of aw (p < 0.001), moisture (p < 0.001), total fat (p < 0.001), protein (p < 0.001), and haem pigments (p < 0.001). The diet significantly impacted the NaCl content (p < 0.05). However, neither the product nor the diet affected the fractions of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), or polyunsaturated fatty acids (PUFA) (p > 0.05). However, a significant difference was observed for n-3 (p < 0.05). Adding olive cake increased these fatty acids, and the diet containing 25% centrifuged olive cake showed the highest levels for both products. Compared with the control, the diets containing olive cake had a higher content of n-3 fatty acids, resulting in a lower PUFA n-6/n-3 ratio (p < 0.01).

A new HS-SPME-GC-MS analytical method to identify and quantify compounds responsible for changes in the volatile profile in five types of meat products during aerobic storage at 4 °C

Nowadays, it is important to monitor the freshness of meat during storage to protect consumers' health. Volatile organic compounds (VOCs) are responsible for odour and taste of food, and they give an indication about meat quality and freshness. This study had the aim to seek and select potential new markers of meat spoilage through a semi-quantitative analysis in five types of meat (beef, raw and baked ham, pork sausage and chicken) and then to develop a new quantitative analytical method to detect and quantify potential markers on five types of meat simultaneously. Firstly, a new headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) method was developed to evaluate the volatile profile of five types of meat, preserved at 4 °C for 5 days. Among the 40 compounds identified, 15 were chosen and selected as potential shelf-life markers on the basis of their presence in most of meat samples or/and for their constant increasing/decreasing trend within the sample. Afterwards, a quantitative HS-SPME-GC-MS analytical method was developed to confirm which VOCs can be considered markers of shelf-life for these meat products, stored at 4 °C for 12 days. Some of the compounds analyzed attracted attention as they can be considered markers of shelf-life for at least 4 types of meat: 1-butanol, 3-methylbutanol, 1-hexanol, 2-nonanone, nonanal, 1-octen-3-ol and linalool. In conclusion, in this study a new quantitative HS-SPME-GC-MS analytical method to quantity 15 VOCs in five types of meat was developed and it was demonstrated that some of the compounds quantified can be considered markers of shelf-life for some of the meat products analyzed.

Characterization of aroma characteristics of silver carp mince glycated with different reducing sugars

The purpose of this study was to investigate the volatile flavor changes in silver carp mince (SCM) gel glycated with different reducing sugars (glucose, L-arabinose, and xylose) based on E-nose, GC-IMS, and sensory evaluation. These results showed that glycation reduced the fishy smell of SCM gel and increased the meaty, toasty, and burnt smell. A total of 10 volatile compounds were considered as characteristic flavor compounds and potential markers. Among them, the main contributors of fishy included hexanal, heptanal, n-nonanal, octanal, etc. Toasty and burnt were mainly related to the production of 3-methylbutanal and furfurol. These results heralded that glycation could be used to improve the volatile flavor of SCM. This research provided a theoretical basis and technical support for glycation in aquatic food flavor quality control, aquatic pre-made food development, and aquatic leisure food processing.

Effect of Starter Culture and Temperature on the Flavor and Sensory Characteristics of Dry-Cured Ham

This study focused on understanding the effects of yeast and mold on the sensory properties of dry-cured ham aged at 20°C and 25°C. Debaryomyces hansenii isolated from Doenjang and fermented sausages, and Penicillium nalgiovense isolated from fermented sausages were utilized. The CIE a* tended to increase in all treatments as the aging period increased. At 6 weeks of aging, DFD25 showed a significantly higher CIE a* value than other treatments. The shear force tended to increase in all treatments as the aging period increased. At 6 weeks of aging, among the treatments aged at 25°C, DFD25 showed a low tendency to shear force. The PC1 of the electronic nose was 42.872%. At 25°C, the hexane content was higher and levels of ethanol, propan-2-one, 2,4,5-trimethylthiazole, and limonene were lower than that at 20°C. DFD25 showed significantly higher hexane content and significantly lower limonene content than other treatments. The PC1 of the electronic tongue was 84.529%. All treatments, except for the C starter, exhibited higher salt and lower sour levels at 25°C compared to 20°C when the same starter was used. The DFD25 showed the lowest sour taste and a higher tendency of umami than the other treatments. Sensory evaluation revealed that DFD25 had significantly higher scores for texture than C25, whereas no significant differences were observed in other aspects. Therefore, the used starters are considered suitable for aging at 25°C; among them, the DFD starter demonstrates superior qualities and enhanced commercial potential compared to the control.

The Characterization of the Key Aroma Compounds in Non-Smoked Bacon by Instrumental and Sensory Methods

The aroma profiles in non-smoked bacon were investigated via GC-O-MS, GC × GC-TOFMS, and GC-IMS. GC-O-MS is advantageous for detecting aldehydes. GC × GC-TOFMS is more sensitive to hydrocarbons and alcohols, while GC-IMS detects a balanced range of categories. Only 9 of the 239 detected volatiles were identifiable by all three methods. Therefore, the combination of all three methods proved to be the most effective way to comprehensively analyze the aroma profiles of bacon. Recombination and omission tests were performed using aroma compounds with a flavor dilution (FD) factor greater than 27; five volatiles were identified as key aroma compounds in non-smoked bacon, including hexanal, (E,E)-2,4-decadienal, 1-octen-3-ol, dihydro-5-pentyl-2(3H)-furanone, and 3-methyl-butanoic acid. Among these, hexanal and 1-octen-3-ol exhibited relatively high FD factors and odor activity values (OAVs), so they were confirmed as the primary contributors. Meanwhile, seven volatiles contributed to the unique aroma of non-smoked bacon in different regions. The difference in the aroma of bacon in different regions is mainly due to the content of various volatiles rather than the type. A comprehensive analysis of the aroma in non-smoked bacon can reveal theoretical information for improving the process and quality control of the product.

Enhancement of fermented sausage quality driven by mixed starter cultures: Elucidating the perspective of flavor profile and microbial communities

The metabolic activities of microorganisms play a crucial role in the quality development of fermented sausage. This study investigated the effect of inoculation with different combinations of starter cultures (Lactiplantibacillus plantarum YR07, Latilactobacillus sakei L.48, Staphylococcus xylosus S.14, and Mammaliicoccus sciuri S.18) on the quality of sausages. Inoculation with mixed starter cultures promoted protein degradation to generate amino acids and the conversion to volatile compounds, which enhanced the flavor development in fermented sausages. The bacterial community analyses demonstrated that the inoculation of mixed starter cultures could inhibit the growth of spoilage and pathogenic bacteria, thereby reducing the total content of biogenic amines. The correlation analysis between the core bacteria and characteristic volatile compounds revealed that fermented sausages inoculated with Lactobacillus and coagulase negative staphylococci exhibited significant positive correlations with the majority of key characteristic volatile compounds. In four treatments, inoculation with L. plantarum YR07 and M. sciuri S.18 greatly promoted the formation of characteristic volatile compounds (3-hydroxy-2-butanone, hexanal, and 1- octen-3ol). Therefore, the combined inoculation of L. plantarum YR07 and M. sciuri S.18 is promising to enhance fermented sausage's flavor profile and safety.

Transcriptomic analysis of the longissimus thoracis muscle in pigs has identified molecular regulatory patterns associated with meat quality

Meat quality is a critical aspect of pig breeding. In addition to genetics, meat quality is also influenced by nutritional and environmental factors. In this study, three pig breeds, Shengxianhua, Jiaxing, and Qinglian Black (SXH, JXB and QLB), were used as experimental animals. Transcriptional analysis was performed on the longissimus thoracis (LT) muscle to investigate variations in intramuscular fat (IMF), inosine monophosphate (IMP), amino acids, and muscle fiber morphology across different breeds. Ingenuity canonical pathway analysis (IPA) identified biological processes and key driver genes related to metabolism and muscle development. Additionally, weighted gene co-expression network analysis (WGCNA) revealed gene modules associated with IMP. KEGG and GO analyses identified specific biological processes and signaling pathways related to IMP, including the Oxidative Phosphorylation pathway and rRNA Metabolic Processes. These findings provide novel insights into the molecular regulatory mechanisms underlying meat quality variations among pig breeds.

Role of microbiota and its ecological succession on flavor formation in traditional dry-cured ham: a review

Traditional dry cured ham (DCH) is favored by consumers for its distinctive flavor, derived from an array of volatile organic compounds (VOCs). Microbiota play a pivotal role in the formation of VOCs. To fully comprehend the pathway by which the microbiota enhance the flavor quality of DCH, it is imperative to elucidate the flavor profile of DCH, the structural and metabolic activities of the microbiota, and the intricate relationship between microbial and VOCs. Thus far, the impact of microbiota on the flavor profile of DCH has not been comprehensively discussed or reviewed, and the succession of bacteria, especially at distinct phases of processing, has not been adequately summarized. This article aims to encapsulate the considerable potential of ferments in shaping the flavor characteristics of DCH, while elucidating the underlying mechanisms through which VOCs are generated in hams via microbial metabolism. Throughout the various stages of DCH processing, the composition of microbiota undergoes dynamic changes. Furthermore, they directly participate in the formation of VOCs in DCH through the catabolism of amino acids, metabolism of fatty acids, and the breakdown of carbohydrates. Several microorganisms, including Lactobacillus, Penicillium, Debaryomyces, Pediococcus, and Staphylococcus, exhibit considerable potential as fermenters in ham production.

Investigation of textural and physicochemical changes during the manufacturing process of pastırma, a dry-cured meat product

The changes in textural and physicochemical properties and stability of meat proteins during the production of pastırma were studied. Samples taken at different production stages (raw material, curing, first drying, second drying and final product) were analyzed. The pH decreased at the end of the curing but increased after the first and second drying. While moisture content and water activity decreased throughout the pastırma production, salt content and Thiobarbituric acid-reactive substances (TBARS) increased. Production stages affected the free fatty acids, residual nitrite content and color parameters (P < 0.01). These results showed that considerable physicochemical changes occurred in the production stages of pastırma. The denaturation temperatures for myosin and actin decreased at the end of the curing, however, no denaturation peak for myosin was observed in the later stages. Hardness, cohesiveness and chewiness increased throughout the pastırma production. Warner-Bratzler (WB) shear force increased at the end of the first drying and in the final product. These results are important in terms of obtaining the desired textural properties in the final product. Also, remarkable correlations were detected among the determined properties during the manufacturing process. The study provided considerable findings for the development of industrial pastırma production.

Flavor profile of "Dao Ban Xiang" (a traditional dry-cured meat product in Chinese Huizhou cuisine) at different processing stages in winter and summer

"Dao Ban Xiang" is a famous traditional Chinese dry-cured meat product. This study aimed to comparatively analyze the difference in the volatile flavor information of "Dao Ban Xiang" produced in winter and summer. In this study, we determine the physical and chemical properties, free amino acids (FAAs), free fatty acids (FFAs), and volatile compounds in the four processing stages of samples in winter and summer. The content of FAAs decreased significantly during the curing period in winter while increasing steadily in summer. The content of total FFAs increased in both winter and summer, and polyunsaturated fatty acids (PUFAs) decreased significantly in summer. The characteristic compound in winter samples is hexanal, nonanal, and (E)-2-octenal, which may mainly come from the degradation of FAAs, while the characteristic compound in winter samples is hexanal, nonanal, and (E)-2-nonenal, which may mainly be derived from the oxidation of FFAs. This study extends our knowledge on flavor from traditional cured meat products at different processing stages in different seasons and could be useful for the standardization of the traditional and regional meat products.

Flavour Profile of Traditional Dry Sausage Prepared with Partial Substitution of NaCl with KCl

The effects of partial substitution of NaCl with 0%, 20%, 30% and 40% KCl on the physical characteristics, bacterial community and flavour profile of traditional dry sausage were investigated in this study. With the increase in KCl substitution ratio, the moisture content, astringency, bitterness and umami increased significantly, and the saltiness gradually decreased (p < 0.05). The high-throughput sequencing results showed that the dry sausages with KCl substitution had relatively high abundances of Staphylococcus. For volatile compounds, increasing the KCl substitution ratio reduced the formation of aldehydes, ketones and some alcohols, but promoted the formation of acids and esters (p < 0.05). Sensory evaluation and partial least square regression analysis showed that the dry sausages with 20% and 30% KCl were similar in overall physical and microbial properties, flavour profiles and sensory attributes, and the sausages with 40% KCl were characterized by taste defects. Overall, partial substitution of NaCl with 30% KCl could ensure the acceptable flavour and sensory attributes of dry sausages.

The dynamic changes of flavors and UPLC-Q-Exactive-Orbitrap-MS based lipidomics in mackerel (Scomberomorus niphonius) during dry-cured processing

Dry-cured mackerel is favored by consumers for its suitable salty flavor. Herein, the dynamic changes of volatile compounds and lipids in the mackerel, and the lipidomics based on UPLC-Orbitrap/MS technique during dry-cured processing were investigated. The results showed that endogenous lipases activities in dry-cured mackerel decreased. The dry-cured processing of mackerel had significant effects on its lipid classes and content. The contents of Arachidonic acid (C20:4n6), docosapentaenoic acid (C22:5n3), linoleic acid (LA, C18:2n6), alpha-linolenic acid (C18:3n3), eicosatrienoic acid (C20:3n3) and docosahexaenoic acid (DHA, C22:6n3) increased during dry-cured processing. A total of 38 kinds of volatile compounds were detected in the dry-cured mackerel, 12 of which were derived from fatty acid oxidation. Among 30 lipid metabolites (FC ≥ 2 and VIP > 2), phosphatidylethanolamine (PE, 19:0/22:6) accounted for the highest content, and its difference between three stages was the most obvious. Glycerophospholipid and sphingolipid metabolisms were the most important metabolic pathways involved in dry-cured processing.

Analysis of Volatile Compounds in Jinhua ham Using Three Extraction Methods Combined with Gas Chromatography-Time-of-Flight Mass Spectrometry

The volatile compounds in Jinhua ham samples after different aging times were characterized using solvent-assisted flavor evaporation (SAFE), solid-phase microextraction (SPME), and needle trap (NT) extraction methods combined with gas chromatography-time-of-flight mass spectrometry (GC-TOF/MS). Hundreds of aroma compounds were identified, including aldehydes, alcohols, ketones, furans, esters, acids, pyrazines, and sulfides. The results showed that NT extracted the greatest number of volatile compounds, whereas the extraction efficiency of SPME headspace adsorption was highest among the three sample preparation methods. Principal component analysis of SPME effectively distinguished the variation in the aroma of the Jinhua hams specific to aging time. Butyrolactone, 2,6-dimethylpyrazine, 2,3,5-trimethylpyrazine, phenylacetaldehyde, and acetic acid were considered as the main volatile compounds in the Jinhua ham samples at three years of aging. The results showed that SPME-GC-TOF/MS effectively discriminated among samples by age. By comparing the three extraction methods, this study provides a theoretical basis for the selection of extraction methods of volatile aroma compounds in Jinhua ham.

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.

Changes in the Physical-Chemical Properties and Volatile Flavor Components of Dry-Cured Donkey Leg during Processing

In order to explore the quality variation and flavor formation of dry-cured donkey leg, the changes in physical−chemical composition, lipolytic, free amino acids content and volatile flavor compounds were investigated in this study. Six fresh, trimmed hind legs with average weight of 8.12 ± 0.8 kg were taken from male Dezhou donkeys slaughtered at the age of 24 months with the average live weight of 240 kg. The entire processing time was eight months long including six stages, specifically: cooling, salting, air-drying, fermenting and aging. Samples were collected at 0 d, 10 d, 20 d, 30 d, 65 d, 105 d and 165 d of processing. The results showed that the pH value remained stable in the range of 6.2~6.6. The moisture and water activity significantly decreased (p < 0.05) during processing. The chloride content, ash, total volatile basic nitrogen (TVB-N) and peroxide value (POV) significantly increased (p < 0.05), from 0.45% to 12.39%, from 3% to 17%, from 1.43 mg/kg to 8.98 mg/kg and from 1.39 g/100 g to 5.26 g/100 g, respectively. The thiobarbituric acid (TBARS) value reached its highest value of 0.39 mg MDA/kg at the end of the salting stage and then decreased to 0.34 mg MDA/kg. Eighteen free amino acids and fifteen free fatty acids were detected, and their contents were significantly increased during processing (p < 0.05). Volatile compounds were analyzed using solid-phase microextraction (SPME) and gas chromatography−mass spectrometry (GC−MS). Among 114 volatile compounds detected in dry-cured donkey leg, aldehydes, esters, alkane and alcohols were more abundant in the final products, with relative concentrations of 41.88%, 5.72%, 5.35% and 5.25%, respectively. Processing significantly affected the physical−chemical properties, which could contribute to the formation of flavor substances of dry-cured donkey leg.

Chemical, Physicochemical and Sensorial Characterization of Nitrite-Free Dry-Cured Bísaro Shoulders

The aim of the current experiment was to characterize and evaluate the effect of the dry-curing process on chemical composition, physicochemical properties, and sensory characteristics of the dry-cured Bísaro shoulders. For this purpose, thirty-eight raw forelegs were used, and no nitrites were added during the dry-curing process. This process increased protein, fat, ash content, and pH, with a decrease in moisture and water activity (p < 0.001). The dry-cured shoulders were darker (L*), less red (a*), and less yellow (b*) than the raw shoulders (p < 0.001), and this may be mainly due to the moisture reduction. The proportion of polyunsaturated fatty acids (PUFA) decreased during processing, whereas the saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) increased (p < 0.001), which could be related with the oxidative degradation. The sensory analysis showed that dry-cured Bísaro shoulders presented similar organoleptic characteristics to other dry-cured meat products. Also, the chemical composition and fatty acid profile of the dry-cured Bísaro shoulder showed results comparable to those of other cured products. This study revealed that it is possible to obtain safer and healthier dry-cured Bísaro shoulder products judging by these characteristics, since nitrites were not added in its preparation. These findings, along with the product’s high sensory attributes similar to more popular products such as ham, would give more advantage for its acceptability and market demand.

Comparative Elucidation of Aroma, Key Odorants, and Fatty Acid Profiles of Ivorian Shea Butter Prepared by Three Different Extraction Methods

In the present study, the volatile compounds, key odorants, and fatty acid profiles of Ivorian shea butter produced by cold press extraction (CPE), solvent extraction (SE) and traditional extraction (TE) methods were investigated for the first time. The aroma compounds of shea butter were extracted by the purge and trap method and analyzed by the gas chromatography–mass spectrometry and olfactometry (GC-MS/O) technique. Totals of 51, 49 and 46 aroma compounds were determined in samples from CPE, SE and TE, respectively. It was observed that the volatile compounds of studied material dominated after CPE, in which alcohols (11) were the most abundant chemical group, followed by aldehydes (10) and acids (7). The application of aroma extract dilution analysis (AEDA) resulted in 22, 20, and 16 key odorants in shea butter from CPE, SE and TE, respectively. 3-Hexanol with flavor dilution (FD) factors (2048 in CPS, 1024 in SE and 64 in TE) was found to be the most active aroma compound in all samples. In the fatty acid fraction obtained using the gas chromatography–flame ionization detector (GC-FID) method, 22, 24 and 19 fatty acids were detected in samples after CPE, SE and TE, respectively. The highest number of fatty acids was determined in shea butter using CPE (89.98%). Stearic and oleic acids were the most dominant fatty acids, and all samples of shea butter were rich sources of saturated fatty acids (SFAs). Moreover, the SE samples showed the highest values of DPPH (238.36 µM TEq/kg) and ABTS (534.96 µM TEq/kg), while the CPE samples had the highest total phenolic content (104.64 mg GAE/kg). Principal component analysis (PCA) clearly indicated that the extraction technique could quantitatively or qualitatively induce changes. Thus, this investigation demonstrated that extraction methods have a considerable impact on the quality and chemical composition of the presented material.

UPLC-MS-MS-based lipidomics for the evaluation of changes in lipids during dry-cured mutton ham processing

Six key stages in the processing of dry-cured muton ham were selected, and changes in the main lipid metabolites as well as the major pathways involved were identified using a lipidic metabolomics approach based on UPLC-MS-MS. In total, 581 lipid metabolites from 22 subclasses were identified, including 521 significantly differential lipids (p < 0.05, VIP > 1). Glycerolipids (GL) were the most abundant lipids, followed by glycerophospholipids (GP), fatty acyls (FA), and sphingolipids (SL). PCA and OPLS-DA of metabolites showed that the quality of mutton ham changed the most during the P3 fermenting stage, including TG(18:1/18:2/18:3), PE(20:5/18:1), and TG(16:1/18:1/18:4) that were significantly downregulated, and CE(20:3), FFA(24:6), LPC(20:3/0:0), and FFA(18:4) that were significantly upregulated. Moreover, glycerophospholipid metabolism and sphingolipid metabolism were the key metabolic pathways involved in the processing of dry-cured mutton ham. Our results provide a basis for quality control and product improvement of dry-cured mutton ham.

Effects of Different Pre-drying and Drying Methods on Volatile Compounds in the Pericarp and Kernel of Amomum tsao-ko

The effects of twelve different pre-drying and drying methods on the chemical composition in the pericarp and kernel of Amomum tsao-ko were studied. The volatile components were isolated from the samples by simultaneous distillation and extraction and analyzed by gas chromatography-mass spectrometry (GC-MS). Sixty and thirty-eight compounds were identified from pericarp and kernel, respectively, and the main constituents were oxygenated monoterpenes. These compounds were not only significantly affected by pre-drying and drying methods but also varied in content due to different tissue locations. The total volatile content of pericarp varied from 0.70 to 1.55%, with the highest obtained by microwave-dried samples (150 W) and the lowest in freeze-dried samples. The total volatile content of the kernel varied from 6.11 to 10.69%, with the highest content obtained during sun drying (SD) and the lowest content in samples treated with boiling water for 2 min. Oxygenated monoterpenes were the highest compounds in pericarp and kernel, which were also the most affected by drying methods. The highest content of oxygenated monoterpenes in the pericarp (0.77%) could be obtained by boiling water treatment for 5 min, and the highest content of oxygenated monoterpenes in the kernel (7.48%) could be obtained by SD. Additionally, the main components such as 1,8-cineole, 2-carene, (Z)-citral, nerolidol, (Z)-2-decenal, (E)-2-dodecenal, citral, (E)-2-octenal, 4-propylbenzaldehyde, and phthalan showed remarkable variations in pre-drying and drying methods.

Health and safety aspects of traditional European meat products. A review

Meat products constitute one of the most important groups of traditional foods. Thanks to the unique and favorable organoleptic characteristics, and high quality, they are willingly chosen by consumers. Lately, there has been a growing concern over the health aspects of these products. Therefore, the aim of this study was to analyze the nutritional value and factors affecting quality and health safety of traditional meat products on the basis of available literature. The study findings have revealed various issues with uniformity of traditional meat products. Products of the same name may differ substantially considering nutritional value. Reports also indicate that there are some discrepancies which can be attributed to product character (traditional/conventional). They mainly concern the content of moisture, protein, salt, fat, and fatty acid profile. Research suggests that traditional meat products may also be associated with some health safety issues, such as the presence of pathogens, polycyclic aromatic hydrocarbons, nitrate and nitrite residues, N-nitrosamines, biogenic amines and heavy metals.

An evaluation of biochemical, structural and volatile changes of dry-cured pork using a combined ion mobility spectrometry, hyperspectral and confocal imaging approach

BACKGROUND

Food processing induces various modifications that affect the structure, physical and chemical properties of food products and hence the acceptance of the product by the consumer. In this work, the evolution of volatile components, 2-thiobarbituric acid reactive substances (TBARS), moisture content (MC) and microstructural changes of pork was investigated by hyperspectral (HSI) and confocal imaging (CLSM) techniques in synergy with gas chromatography-ion mobility spectrometry (GC-IMS). Models based on partial least squares regression (PLSR) were developed using the full HSI spectrum variables as well as optimum variables selected through a competitive adaptive reweighted sampling algorithm.

RESULTS

Prediction results for MC and TBARS using multiplicative scatter correction pre-processed spectra models demonstrated greater efficiency and predictability with determination coefficient of prediction of 0.928, 0.930 and root mean square error of prediction of 0.114, 1.002, respectively. Major structural changes were also observed during CLSM imaging, which were greatly pronounced in pork samples oven cooked for 15 and 20 h. These structural changes could be related to the denaturation of the major meat components, which could explain the loss of moisture and the formation of TBARS visualized from the HSI chemical distribution maps. GC-IMS identified 35 volatile components, including hexanal and pentanal, which are also known to have a higher lipid oxidation specificity.

CONCLUSION

The synergistic application of HSI, CLSM and GC-IMS enhanced data mining and interpretation and provided a convenient way for analyzing the chemical, structural and volatile changes occurring in meat during processing. © 2021 Society of Chemical Industry.

The Quality of Horsemeat and Selected Methods of Improving the Properties of This Raw Material

Horsemeat has a strictly defined group of consumers whose demand varies depending on the country or region. There is no tradition of consuming horsemeat in Poland. From a technological point of view, this raw material is as good as other types of meat. In the opinion of the consumer, compared to other species of animals, horsemeat is characterized by an intense red-brown colour and greater cohesiveness resulting from the type of muscle fibres. This meat has a sweetish taste due to the high carbohydrate content. The management of horsemeat often involves the use of modern freezing methods. Freezing horsemeat with the use of liquefied carbon dioxide is a method that increases its suitability for consumption as well as for export purposes in comparison with the traditional air-cooling method. To eliminate the unfavourable quality features of horsemeat, there are substances used to improve the functional and sensory properties of this meat. This paper discusses the research and development work carried out in the field of horsemeat quality and selected methods contributing to its improvement.

Natural Antioxidants from Endemic Leaves in the Elaboration of Processed Meat Products: Current Status

During the last few years, consumers' demand for animal protein and healthier meat products has increased considerably. This has motivated researchers of the meat industry to create products that present healthier components while maintaining their safety, sensory characteristics, and shelf life. Concerning this, natural plant extracts have gained prominence because they can act as antioxidants and antimicrobials, increasing the stability and shelf life of processed meat products. It has been observed that the leaves of plant species (Moringa oleifera, Bidens pilosa, Eugenia uniflora, Olea europea, Prunus cerasus, Ribes nigrum, etc.) have a higher concentration and variety of polyphenols than other parts of the plants, such as fruits and stems. In Chile, there are two native berries, maqui (Aristotelia chilensis) and murtilla (Ugni molinae Turcz), that that stand out for their high concentrations of polyphenols. Recently, their polyphenols have been characterized, demonstrating their potential antioxidant and antimicrobial action and their bioactive action at cellular level. However, to date, there is little information on their use in the elaboration of meat products. Therefore, the objective of this review is to compile the most current data on the use of polyphenols from leaves of native plants in the elaboration of meat products and their effect on the oxidation, stability, and organoleptic characteristics during the shelf life of these products.

Relationship between volatile organic compounds, free amino acids, and sensory profile of smoked bacon

Flavor is one of the most important characteristics of smoked bacon, strongly affecting its liking by consumers. The smoking process, lipid oxidation and proteolysis contribute to bacon quality through the generation of odors and flavor compounds. In this study, the relationships between free amino acids (FAAs), volatile organic compounds (VOCs) and sensory characteristics of smoked bacon stored for 60 days at 5 °C were investigated. Smoked bacon stored for 30 days was characterized by VOCs associated with the smoking process and lipid oxidation. After 30 days of storage, the bacon samples presented an increase in FAAs produced mainly by proteolysis. Smoked bacon was characterized by the attributes smoky, crunchy, salty, soft and bright. This study demonstrated that VOCs, FAAs and their interactions are responsible for generating sensory attributes and increasing overall liking.

Influence of induction cooking on the flavor of fat cover of braised pork belly

Fat has a great impact on texture and flavor of meat products, which is influenced by cooking methods. In this study, the profiles of fatty acids, volatile compounds, and texture of fat cover of braised pork belly were investigated after plane and concave induction cooking. The results showed that cooking time showed a great impact on fat content, textural properties, fatty acids composition, lipid oxidation, and volatile compounds of fat cover (p < 0.05). When cooking time was fixed, concave induction cooking caused lower hardness, chewiness, and saturated fatty acids but higher polyunsaturated fatty acids at 60 min than plane induction cooking. Electronic nose and GC-MS analyses showed that concave induction cooking had a greater impact on flavor of pork belly fat and produced a comparable flavor to plane induction cooked samples in a shorter time. Sensory evaluation showed that concave induction cooking had higher scores at 60 min. Thus, concave induction cooking could be a more efficient method for meat processing. PRACTICAL APPLICATION: Electromagnetic induction heating is an effective cooking technique. It is characterized by uniformity, efficiency, and safety of heating. The application of electromagnetic induction heating technology to the cooking of braised pork was studied, which provides information for further optimizing the cooking technology of braised pork and improving the quality of braised pork.

Effect of NaCl Partial Replacement by Chloride Salts on Physicochemical Characteristics, Volatile Compounds and Sensorial Properties of Dry-Cured Deer Cecina

The present study aimed to evaluate the effect of NaCl replacement in the physicochemical quality and volatile and sensorial profile of dry-cured deer cecina. Two salt mixtures were used as NaCl substitute: mixture I (30% NaCl-70% KCl) and mixture II (30% NaCl-50% KCl-15% CaCl₂-5% MgCl₂). Regarding the physicochemical parameters, only ash content, pH and L* values were affected by NaCl replacement. However, lipid oxidation was affected by NaCl replacement. The greatest thiobarbituric acid reactive substances (TBARS) values were observed in the control batch (3.28 mg MDA/kg). The partial replacement of NaCl by salt mixtures affected (p < 0.001) Ca, K, Mg, and Na content. The total amounts of free fatty acids and free amino acids were not affected (p > 0.05) by NaCl replacement. Concerning the volatile compounds, control samples presented the highest concentrations of furans (p < 0.01), while samples produced with mixture II had the lowest (p < 0.001) amounts of esters and acids. Our results indicated that all sensory attributes of the attribute map were affected (generalized procrustes analysis (GPA) explained 100% of the total variability among treatments). Considering the results obtained from the sensorial analysis, only mixture II reduced the overall acceptance and preference of consumers. Control attained significantly (p < 0.05) greater scores of acceptance and preference than mixture II despite the higher TBARS content.

Comparative Studies on the Fatty Acid Profile and Volatile Compounds of Fallow Deer and Beef Fermented Sausages without Nitrite Produced with the Addition of Acid Whey

This study aims to improve knowledge on fermented beef and fallow deer sausages and the effect of nitrite elimination and the addition of freeze dried acid whey on the fatty acid profile and volatile compounds. Three different formulations within each of the two product groups, made of beef and fallow deer meat, respectively, were prepared: control sample with sodium nitrite, sample without nitrite, and sample without nitrite and with the addition of freeze-dried acid whey powder (0.7%). After production, the sausages were subjected to analysis including proximate chemical composition, pH and water activity, Thiobarbituric Acid Reactive Substance (TBARS), fatty acid profile, and volatile compound determination. The fermented sausages were characterized by an average pH and water activity in the range of 5.23–5.79 and 0.910–0.918, respectively. Fallow deer sausages were characterized by a higher content of saturated and polyunsaturated fatty acids in comparison to beef sausages. The elimination of nitrite did not significantly affect the amount of volatile compounds in fermented sausages. However, the effect of the freeze-dried acid whey powder addition on the amount of some volatile compounds in uncured sausages was observed, in particular, that derived from bacterial metabolism.

Effects of partial NaCl substitution with high-temperature ripening on proteolysis and volatile compounds during process of Chinese dry-cured lamb ham

The effects of partial NaCl substitution combined with high-temperature ripening on the proteolysis and formation of volatile compounds in dry-cured lamb ham was investigated. Two salt treatments, I (0% KCl + 100% NaCl) and II (25% KCl + 75% NaCl), were considered. Although some studies have analyzed the influences of salt substitution on volatile compounds of dry-cured ham, no studies have evaluated lamb ham produced in China. Intensifying the high-temperature ripening lead to an increase in the formation of flavors generated by the Maillard reaction and Strecker degradation in both treatments, also, had a positive influence on proteolysis index and content of total free amino acids during the ripening stage. The application of 25% KCl did not influence the formation of volatiles during curing stage, however, there were more volatiles came from amino acids degradation in the final products with 25% KCl. Therefore, sodium reduction combined with high-temperature ripening may be an alternative method to manufacture Chinese dry-cured lamb hams.

Use of Turkey Meat Affected by White Striping Myopathy for the Development of Low-Fat Cooked Sausage Enriched with Chitosan

The main objective of this research was the development of a healthy meat product from turkey meat with white striping myopathy. The effect of adding different proportions of chitosan on the qualitative characteristics, sensory acceptance, and stability of cooked sausages during storage was studied. Three treatments were elaborated (control, 1.5% chitosan, and 3% chitosan), stored for 56 days, and characterized in terms of chemical composition, texture profile analysis, drip and pressure loss analysis, and sensory analysis (after processing; day 0). In the different storage periods (0 and 56 days), the pH value, color, thiobarbituric acid reactive substances (TBARS), and volatile compounds were evaluated. The results showed that the moisture content, lipids, proteins, and weight loss decreased (p < 0.05) and the ash content increased (p < 0.05) with the addition of chitosan. Similarly, the values of texture parameters (hardness, cohesiveness, gumminess, and chewiness) were higher in the sausages reformulated with chitosan than in control samples. The addition of chitosan increased the pH and yellowness (b*) values and reduced (p < 0.05) redness (a*) and lightness (L*) values. The b* values (only in reformulated sausages) and pH increased during storage, while a* showed a significant reduction after 56 storage days. Lipid oxidation (TBARS) was kept below the limits of quantification in all samples and both after processing and 56 storage days. However, when quantifying the lipid-derived volatiles, a clear antioxidant activity of chitosan was observed, which limits the release of these compounds, mainly aldehydes (hexanal and nonanal). Finally, the sensory analysis indicated that, although chitosan treatments received the lowest scores for all attributes, the reformulated samples did not differ from control sausages. Therefore, sausage containing chitosan may represent an interesting alternative for adding value to turkey meats affected by white striping myopathy and, at the same time, develop into a healthy and functional meat product increasing the proportion of fibers in one’s diet.

Inclusion of Healthy Oils for Improving the Nutritional Characteristics of Dry-Fermented Deer Sausage

The influence of partial replacement of animal fat by healthy oils on composition, physicochemical, volatile, and sensory properties of dry-fermented deer sausage was evaluated. Four different batches were manufactured: the control was formulated with animal fat (18.2%), while in the reformulated batches the 50% of animal fat was substituted by olive, canola, and soy oil emulsions immobilized in Prosella gel. The reformulation resulted in a decrease of moisture and fat contents and an increase of protein and ash amount. Moreover, reformulated sausages were harder, darker, and had higher pH values. This fact is related to the lower moisture content in these samples. As expected, the fatty acid composition was changed by the reformulation. The use of soy and canola oils increased polyunsaturated fatty acids and omega-3 content and decreased n-6/n-3 ratio and saturated fatty acids. Thus, the use of these two oils presented the best nutritional benefits. The changes observed in the fatty acids reflected the fatty acid composition of the oils employed in the emulsions. Regarding volatile compounds (VOC), the replacement of animal fat by healthy emulsion gels increased the content of both total VOC and most of individual VOC. However, the lipid-derived VOC did not show this trend. Generally speaking, the control samples presented similar or higher VOC derived from lipid oxidation processes, which could be related to the natural antioxidant compounds present in the vegetable oils. Finally, all reformulated sausages presented higher consumer acceptability than control samples. In fact, the sausage reformulated with soy oil emulsion gel was the most preferred. Thus, as a general conclusion, the reformulation of deer sausages with soy emulsion gel improves both composition and sensory quality of the final product, which could be an excellent strategy to the elaboration of healthy fermented sausages.

The Effect of Citric Acid, NaCl, and CaCl2 on Qualitative Changes of Horse Meat in Cold Storage

In this study, we aimed to analyze the effect of citric acid, NaCl, and CaCl2 on the qualitative changes of horse meat during cold storage. The study material was the longest dorsal muscles (M. longissimus dorsi (LM)) obtained from twelve half-carcasses of horses. The muscle was cut into five steaks, each of which was about 3 cm thick. One sample was kept as a control sample, and the remaining ones were treated with NaCl, citric acid, and CaCl2 (0.2 M and 0.3 M). The study material was obtained 24 h after the slaughter of the animals and was marinated in solution (citric acid and 0.2 M and 0.3 M calcium chloride) and by sprinkling and rubbing (sodium chloride). The applied treatments significantly (p ≤ 0.05) improved the texture parameters of horse meat (univariate analysis of variance). Citric acid caused deterioration of the study material with respect to the binding and retention of intrinsic water. Among the tested material, the lightest color of the meat was obtained for sample marinated in 0.3 M CaCl2. However, the darkest color of the meat was obtained after the addition of NaCl.

Turmeric (Curcuma longa L.) extract on oxidative stability, physicochemical and sensory properties of fresh lamb sausage with fat replacement by tiger nut (Cyperus esculentus L.) oil

This study aimed to evaluate the effect of turmeric extract as natural antioxidant on modified atmosphere-packaged fresh lamb sausages with fat replacement during storage (2 °C). Five treatments were prepared: control without antioxidant (CONT); with 500 mg/kg sodium erythorbate (E500); and three batches with 250, 500 or 750 mg/kg turmeric extract (T250, T500 and T750), respectively. The proximate composition, pH, color, texture, oxidative stability, sensorial analysis, free fatty acids and volatile compounds of sausages were analyzed. Turmeric extract improved the antioxidant capacity of lamb sausages and also slowed lipid oxidation and the generation of related volatile compounds. Moreover, physic-chemical parameters of lamb sausages were not greatly influenced by turmeric addition and concentration, except for yellow color. All samples were considered acceptable by consumers. These findings showed that turmeric extract is effective against lipid oxidation and could be a good strategy to enhance the shelf life of lamb sausage.

Effects of aging and dietary supplementation with polyphenols from Pinus taeda hydrolysed lignin on quality parameters, fatty acid profile and oxidative stability of beef

Context The inclusion of Pinus taeda hydrolysed lignin (PTHL) in beef diets could improve quality and stability of meat, but effects could vary through the aging period (AP). Aim The aim was to evaluate the effects of the PTHL inclusion in the diet of finishing beef cattle on meat quality, fatty acid composition and oxidative stability at Days 1, 8, 11 and 15 of aging. Methods Forty Limousin bulls (340 ± 42 kg) were fed ad libitum on a total mixed ration (TMR). The control group received exclusively TMR for 120 days, while the experimental group received the same TMR as the control group but supplemented with PTHL (Oxifenol, I-Green, Padua, Italy; 35 g/day per head at 1–90 days and 70 g/day per head at 91–120 days). Key results Diet did not influence the chemical composition, pH, cooking loss, Warner–Bratzler shear force and hydroperoxide content. The Warner–Bratzler shear force (P &lt; 0.001) decreased, while lightness (P &lt; 0.01) and hydroperoxides (P &lt; 0.001) increased through the aging period. Thiobarbituric acid reactive substances were similar for both diets at 1 and 15 days. However, thiobarbituric acid reactive substances at 8 and 11 days were higher for control than for the PTHL diet (P = 0.023 for interaction). Protein carbonyls were higher for control than for the PTHL diet at 8 days (P = 0.003 for interaction), but similar for both diets for the other dates. Saturated, monounsaturated and polyunsaturated fatty acids varied through the AP with PTHL diet, while no changes were observed with control diet (P &lt; 0.01 for interactions). At 11 days, the n-6:n-3 ratio passed from being the minimum value with the PTHL diet to be the maximum with control diet (P &lt; 0.01 for interaction). Conclusions The effects of PTHL inclusion in bull finishing diets depends on the AP but, generally, may result in beef with meat with beneficial effects on human health. Implications Including PTHL in the diet of finishing bulls can be useful to improve meat quality, favouring the use of natural waste substances deriving from vegetal production.

Substitution effects of NaCl by KCl and CaCl2 on Lipolysis of Salted Meat

The objective of this study was to investigate the reduction and partial substitution effects of sodium chloride (NaCl) by potassium chloride (KCl) and calcium chloride (CaCl₂) on lipolysis and lipid oxidation in salted meat aiming at reducing sodium content. To evaluate the effect of different salts on lipid oxidation thiobarbituric acid-reactive substances (TBARs) assay was performed along 180 days. Furthermore, ESI-MS/MS and GC analysis were conducted to detect and identify oxidized lipids, volatile compounds and free fatty acids profiles during the meat processing time. Lipid profiles from different salted meat demonstrated that CaCl₂ salt have inducted more lipid oxidation when compared to the combination of NaCl and KCl salts, highlighting the implication of CaCl₂ on increased lipolysis reactions. Moreover, the obtained results from both the analyses suggest that a combination of NaCl and KCl salts can be a good alternative for reducing the sodium content without compromising the quality of the salted meat.