Effects of different drying methods on physicochemical, textural, flavor, and sensory characteristics of yak jerky.

The work aimed to study the effect of four drying methods, namely constant temperature hot air drying (HD), microwave drying (MD), hot air microwave drying (HMD), and gradient hot air drying (GHD), on quality characteristics of dried yak meat. The analyses of physicochemical, textural, flavor, and sensory characteristics were carried out based on these four drying methods. The results revealed that microwave dried yak jerky exhibited better color and received the highest sensory score. Hardness of samples were affected by the drying methods, which showed significant differences. There were 21 free amino acids (FAAs) detected in dried yak samples. The samples treated by microwave drying showed the highest total free amino acid content (73.30 mg/100 g) and the EUC value was significantly higher than other methods, indicating the sample displayed greater flavor. A total of 153 volatile compounds were identified in dried yak meat samples, primarily including aldehydes, ketones, and esters. Moreover, the sensory evaluation indicated that the drying methods could significantly affect on color, flavor, and overall acceptability of different samples. Microwave drying samples scored higher than other drying methods. Overall, considering aspects of quality, time savings, and energy efficiency, microwave drying of yak jerky emerges as a more satisfactory option. This study could provide important theoretical support for the application of drying methods to improve the quality of yak jerky and enhance production efficiency.

Flavor profile analysis of grilled lamb seasoned with classic salt, chili pepper, and cumin (Cuminum cyminum) through HS-SPME-GC-MS, HS-GC-IMS, E-nose techniques, and sensory evaluation on Sonit sheep.

In this study, the volatile flavor profiles of grilled lamb seasoned with salt, chili pepper, and cumin were analyzed employing HS-SPME-GC-MS, HS-GC-IMS, E-nose, and sensory evaluation techniques. The E-nose was found effective in differentiating the samples seasoned variously. A total of 67 volatile compounds were identified by HS-SPME-GC-MS, and 59 by HS-GC-IMS. The PCA demonstrated a correlation between the seasonings and the volatile compounds, with five principal components accounting for 99.54% of the total variance. 1-octen-3-ol, 3-furanmethanol, acetic acid, and heptanal were introduced by salt; compounds like propyl acetate were correlated with chili pepper; a broader range, including ethyl 3-methylbutanoate and high concentrations of alpha-pinene, was associated with cumin. Samples seasoned with all three ingredients showed similarities to those associated with cumin, alongside unique compounds such as gamma-octalactone and alpha-pinene. Sensory evaluations by consumers indicated that the combination of these seasonings significantly enhanced the overall acceptability of the grilled lamb. PRACTICAL APPLICATION: Utilizing modern analytical techniques, this study has successfully revealed the distinct impacts of seasonings-salt, chili pepper, and cumin-on the flavor profile of grilled lamb. By providing experimental data on how each seasonings influence the flavor profile of grilled lamb prepared with Sonit sheep. The research offers theoretical foundation for the development of grilled lamb products. By conducting a thorough comparison between GC-MS and GC-IMS, this study has expanded the understanding of the distinct characteristics of these two technologies. It has also provided a clearer analysis of some flavor compounds dimers produced in GC-IMS system.

Preparation and Investigation of Sustained-Release Nanocapsules Containing Cumin Essential Oil for Their Bacteriostatic Properties.

Cumin essential oil chitosan nanocapsules (CENPs) were prepared through the ionic gelation method by blending chitosan (CS) with cumin essential oil (CEO) in different proportions (1:0.8, 1:1, 1:2, 1:3, 1:4). Subsequently, these nanocapsules were characterized and evaluated for their antibacterial properties to determine the optimal cumin essential oil encapsulation and antibacterial efficacy. The outcomes demonstrated that the highest encapsulation efficiency of CENPs was 52%, achieved with a 1:3 CS/CEO ratio. At this point, the nanoparticles had the smallest particle size (584.67 nm) and a regular spherical distribution in the emulsion. Moreover, the CENPs could release the encapsulated CEOs slowly, leading to efficient inhibition of E. coli and L. monocytogenes over a relatively extended period (24-36 h) compared to the CS and CEO. This research offers a promising approach for the use of nanocapsules in food preservation.

Effect of fat addition on the characteristics and interfacial behavior of chicken white soup emulsion from chicken skeleton.

The effects of varying fat additions (0 %, 1.0 %, 1.5 %, 2.0 %, and 2.5 %) on characteristics and interfacial properties of chicken white soup emulsion from stewing chicken skeleton were investigated. The results revealed that the chicken white soup emulsion obtained with the 2.0 % fat addition had smaller D3,2 (1.889 µm), D4,3 (2.944 µm), and higher absolute zeta potential value (23.32 mV). Viscosity values were higher for the 2.0 % fat addition compared to the other treatment groups. Techniques like scanning electron microscopy, laser confocal, and atomic force microscopy demonstrated that oil droplets and particles in the soup were smaller and more evenly dispersed with the 2.0 % fat addition. Moreover, the 2.0 % fat group exhibited higher interfacial protein concentration of 207.56 mg/m2. Lastly, low field NMR images confirmed that the stability of the soup was enhanced with a 2.0 % fat addition. This research offers a foundational understanding for producing highly stable chicken white soup.

Migration of Nutrient Substances and Characteristic Changes of Chicken White Soup Emulsion from Chicken Skeleton during Cooking.

The protein and fat in chicken skeleton can be emulsified in a boiling state to form milky white chicken soup. White chicken soup has a delicious taste, good nutritional value, a beautiful color, and volatile flavor compounds. However, cooking time significantly impacts the quality of white chicken soup. Herein, we investigated the influence of cooking time (30, 60, 90, 120, 150, 180, and 210 min) on the migration of nutrient substances and characteristics changes in white chicken soup from chicken skeletons. The results showed that nutrients such as total lipids, water-soluble protein, total sugars, solid matter, and oligopeptides in the chicken skeletons' tissue continuously migrated into the soup during the cooking process. The total nutrient content in the chicken soup was highest after cooking for 180 min. Simultaneously, the white chicken soup obtained after cooking for 180 min had low interfacial tension and high whiteness, viscosity, and storage stability. The high stability index was associated with increased ζ potential and decreased particle size. The contact angle analysis results also indicated that the stability of the white chicken soup was improved when the cooking time reached 180 min. This research provides basic information for the production of high-quality white chicken soup.

Using temporal dominance of sensations (TDS), multiple-sip TDS, chemical composition evaluation, and microstructural analysis to assess the impact of repeated reheating cycles on chicken soup.

Reheating chicken soup is a common culinary practice in daily life. To investigate the impact of reheating frequency on the sensory quality of chicken soup, temporal dominance of sensations (TDS) and multi-TDS were used to characterize changes in dominant sensory attributes during consumption. Additionally, E-nose and E-tongue were utilized to analyze differences in aroma and taste profiles. The alterations in sensory properties were further elucidated by analyzing variations in amino acids, volatile compounds. The findings revealed that there was no significant disparity between fresh soup and heating. However, saltiness and umami, as the most prominent dominant characteristics, intensified with increasing reheating cycles. This can be attributed to an elevation in certain amino acids that contribute to umami perception. Conversely, a reduction in some aldehydes weakened the flavor associated with fat and meat components. Moreover, enlarged oil droplets with uneven distribution within heated soup may account for the heightened greasiness sensation.

Effects of catechin on the stability of myofibrillar protein-soybean oil emulsion and the adsorbed properties of myosin at the oil-water interface.

The effects of different concentrations of catechin on the stability of myofibrillar protein-soybean oil emulsions and the related mechanisms were investigated. Adding 10 µmol/g catechin had no obvious effects on the emulsion stability and myosin structure, but 50, 100 and 200 µmol/g catechin decreased the emulsion stability. The microstructure observations showed that 10 µmol/g catechin caused a dense and uniform emulsion to form, whereas 50, 100 and 200 µmol/g catechin induced the merging of oil droplets. The addition of 50, 100 and 200 µmol/g catechin caused a decline in both the total sulfhydryl content and surface hydrophobicity, suggesting protein aggregation, which decreased the adsorption capacity of myosin and the elasticity of interfacial film. These results suggested that higher concentrations of catechin were detrimental to the emulsifying properties of myosin and that the dose should be considered when it is used as an antioxidant.

Exploring the formation pathway and antioxidant properties of the sugar-smoking pigment 5-GGMF.

The present study aimed to elucidate the pathway of pigment formation and identify the source of antioxidant activity during sugar smoking. Building upon previous research, this investigation replicated the sucrose cleavage process involved in sugar-smoking through model reactions to obtain distinct model reaction products. The products were analyzed using various techniques such as ultraviolet-visible spectrometry, Fourier-transform infrared spectroscopy, high-performance liquid chromatography, and high-performance liquid chromatography-tandem mass spectrometry. The findings revealed that the pyrolysis of sucrose at 330 °C yielded glucose and fructose, with fructose pyrolysis producing significantly more 5-HMF than glucose. Moreover, the antioxidant capacity of 5-HMF was found to make a substantial contribution. The primary source of 5-HMF was identified as fructose resulting from the cleavage of sucrose at 330 °C, while the primary pathway for the formation of the sugar-smoking pigment 5-GGMF was attributed to the intermolecular dehydration of 5-HMF and glucose at 150 °C.

Relationship between phospholipid molecules species and volatile compounds in grilled lambs during the heating process.

The present study used a comprehensive analysis combining headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) to investigate changes in volatile compounds and phospholipid molecules in grilled lambs. The results revealed 19 key volatile compounds (OAV > 1) involved in the grilling process of lambs. Additionally, UPLC-ESI-MS/MS analysis detected 142 phospholipid molecules in grilled lamb, with phosphatidylcholine exhibiting the highest content (36.62 %), followed by phosphatidyl ethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidyl glycerol, and phosphatidic acid. Through partial least squares analysis, 63 key differential phospholipids were identified. Principal component analysis of the key differential phospholipids and volatile compounds indicated that phosphatidylcholine and phosphatidyl ethanolamine phospholipids are the key substrates in forming volatile compounds in grilled lambs. This information is essential for precisely regulating the flavor profile, enhancing the grilling process, and minimizing the production of harmful compounds in grilled meat products.

Effect of ultrasound treatment on porcine myofibrillar protein binding furan flavor compounds at different salt concentrations.

The effects of ultrasound (500 W) on the interaction of porcine myofibrillar protein (MP) with furan flavor compounds at different salt concentrations (0.6 %, 1.2 % and 2.4 %) were investigated. With the increase of salt concentration, the particle size of MP decreased, and the surface hydrophobicity and active sulfhydryl content increased due to the unfolding and depolymerization of MP. At the same time, ultrasound promoted the exposure of hydrophobic binding sites and hydrogen bonding sites of MP in different salt concentration systems, thus improving the binding ability of MP with furan compounds by 2 % to 22 %, among which MP had the strongest binding capacity of 2-pentylfuran. In conclusion, ultrasound could effectively promote the unfolding of the secondary structure of MP, which was beneficial to the combination of MP and furan flavor compounds under different salt concentrations.

Characterization of lamb shashliks with different roasting methods by intelligent sensory technologies and GC-MS to simulate human muti-sensation: Based on multimodal deep learning.

To simulate the functions of olfaction, gustation, vision, and oral touch, intelligent sensory technologies have been developed. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) with electronic noses (E-noses), electronic tongues (E-tongues), computer vision (CVs), and texture analyzers (TAs) was applied for sensory characterization of lamb shashliks (LSs) with various roasting methods. A total of 56 VOCs in lamb shashliks with five roasting methods were identified by HS-SPME/GC-MS, and 21 VOCs were identified as key compounds based on OAV (>1). Cross-channel sensory Transformer (CCST) was also proposed and used to predict 19 sensory attributes and their lamb shashlik scores with different roasting methods. The model achieved satisfactory results in the prediction set (R2 = 0.964). This study shows that a multimodal deep learning model can be used to simulate assessor, and it is feasible to guide and correct sensory evaluation.

Characterization of key aroma compounds in Chinese smoked duck by SAFE-GC-O-MS and aroma-recombination experiments.

Smoked duck is a popular meat product in China. The aroma profile and key aroma compounds in smoked ducks were elucidated using solvent-assisted flavor evaporation-gas chromatography-olfactometry-mass spectrometry (SAFE-GC-O-MS), odor activity values (OAVs), aroma recombination and omission experiments, and sensory evaluation. The results indicated that the predominant aroma profiles of rice-, tea oil- and sugarcane-smoked ducks all contained strong smoky, roasty, fatty, meaty, and grassy aromas. A total of 31 aroma compounds were identified as important odorants by OAVs, including 8 aldehydes, 6 pyrazines, 5 phenols, and 2 sulfur compounds. The aroma recombination and omission experiments confirmed that 13 odorants were key aroma compounds in smoked ducks. Of these odorants, 2-methoxyphenol, 4-methylphenol, 5-ethyl-2,3-dimethylpyrazine, methional, 2-methyl-3-furanthiol, (E, E)-2,4-decadienal, 1-octen-3-ol, and anethole significantly contributed to the aroma profile of smoked duck flavor (p < 0.01).

Effects of ultrasound-assisted curing on the quality and microstructure of low-sodium beef jerky.

The effects of ultrasonic brine on the physicochemical properties, sensory quality and microstructure of low-sodium beef jerkies were investigated. Compared with control jerky brined in 1.5% NaCl solution, both of the direct reduction and partial replacement of 50% NaCl by KCl decreased the sodium content. Ultrasonic treatment resulted in sharp reduction in shear force. KCl substitution together with ultrasonic treatment caused the highest yield, a* value and water content, and the water activity of all groups were below 0.85. Only the direct reduction of NaCl had negative effects on the sensory quality. KCl substitution combined with ultrasonic treatment was the most suitable for producing low-sodium beef jerkies with high quality, possibly because the mixed salt had equal total salt content to control. Meanwhile, the cavitation and mechanical effects of ultrasound may unfold protein structure, increase myofibrillar fragmentation index and break the muscle fiber, thus improving the quality of beef jerky.

The effect of thermal times of circulating non-fried roast technique on the formation of (non)volatile compounds in roasted mutton by multi-chromatography techniques and heat transfer analysis.

The circulating non-fried roast (CNR) technology was firstly applied to roast mutton. The formation of (non)volatile compounds in the mutton roasted for 0-15 min was investigated. The samples roasted at varying times were discriminated using GC-O-MS and multivariate data analysis. A total of 40 volatile compounds were observed, in which 17 compounds were considered as key odorants with odor activity values (OAVs) higher than 1, such as dimethyl trisulfide and 2-ethyl-3,5-dimethylpyrazine. Composition and concentrations of volatile compounds were significantly changed during the process. The key nonvolatile compounds that contributed to flavor were 5'-inosine monophosphate (5'-IMP) and glutamic acid based on taste active values (TAVs) greater than 1. The reduced concentrations of most free amino acids and 5'-nucleotides decreased the equivalent umami concentrations (EUC). The higher thermal conductivity, lower thermal diffusivity and water activity were responsible for the formation of volatile compounds with increased roasting times. The CNR technology was an efficient tool to roast meat products.

Comprehensive binding analysis of glycated myosin with furan derivatives via glucose by means of multi-spectroscopy techniques and molecular docking simulation.

Myosin is an ideal binding receptor for aroma compounds and its functional properties are easily affected by glucose. The study comprehensively clarified the effects of glucose glycation-induced structural modifications of myosin on its binding ability with furan derivatives, including 2-methylfuran, 2-furfural, and 2-furfurylthiol. The results demonstrated that the binding levels of furan derivatives were obviously affected by the glycation levels of myosin due to the changes of myosin structure and surface. The increased glycation levels caused the unfolding of myosin structure and accelerated the aggregation, as were exhibited by the data of zeta potential, particle size, microstructure, and secondary structure. The glycated myosin with wrinkled surfaces favored the significant increase of hydrophobic interactions (31.59-69.50 µg), the more exposure of amino acid residues (3459-6048), the formation of free sulfhydryl groups (16.37-20.58 mmol/104g) and hydrogen bonds. These key (non)covalent linkages accounted for the generation of glycated myosin-odorants complex, including 2-furfurylthiol (29.17-47.87 %), thus enhancing the resultant binding ability as evidenced by the free furan derivatives concentrations, fluorescence quenching and molecular docking simulation analysis. The glycated myosin for 8 h bound highest concentrations of furan derivatives. The results will provide comprehensive data on the retention of aroma compounds in meat products.

Understanding the role of lipids in aroma formation of circulating non-fried roasted chicken using UHPLC-HRMS-based lipidomics and heat transfer analysis.

The role of lipids in aroma formation of circulating non-fried roasted (CNR) chicken with different roasting times was studied using ultra-high performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS)-based lipidomics and heat transfer analysis. Thirteen odorants were confirmed as important aroma compounds of CNR chicken, including dimethyl trisulfide, 3,5-dimethyl-2-ethylpyrazine, nonanal, and 1-octen-3-ol. A comprehensive lipidomics analysis identified 1254 lipids in roasted chickens, classified into 23 distinct lipid categories that included 281 phosphatidylcholines (PC), 223 phosphatidylethanolamines (PE), and 202 triglycerides (TG). Using OPLS-DA analysis, the lipid PG (18:1_18:1) showed promise as a potential biomarker for distinguishing between chickens subjected to CNR treatments with varying roasting times. The lipids PC, PE, and their derivatives are likely to play a crucial role in the formation of aroma compounds. In addition, TGs that contributed to the retention of key odorants in roasted chicken included TG (16:0_16:0_18:1), TG (16:0_16:0_18:0), and TG (16:0_18:1_18:1). Findings further showed that lower water activity and specific heat capacity promoted the formation and retention of aroma compounds during the CNR process. This study contributed to a better understanding of the formation of aroma compounds through lipid oxidation in roasted chicken.

Identifying the quality characteristics of pork floss structure based on deep learning framework.

Pork floss is a traditional Chinese food with a long history. Nowadays, pork floss is known to consumers as a leisure food. It is made from pork through a unique process in which the muscle fibers become flaky or granular and tangled. In this study, a deep learning-based approach is proposed to detect the quality characteristics of pork floss structure. Describe that the experiments were conducted using widely recognized brands of pork floss available in the grocery market, omitting the use of abbreviations. A total of 8000 images of eight commercially available pork flosses were collected and processed using sharpening, image gray coloring, real-time shading correction, and binarization. After the machine learning model learned the features of the pork floss, the images were labeled using a manual mask. The coupling of residual enhancement mask and region-based convolutional neural network (CRE-MRCNN) based deep learning framework was used to segment the images. The results showed that CRE-MRCNN could be used to identify the knot features and pore features of different brands of pork floss to evaluate their quality. The combined results of the models based on the sensory tests and machine vision showed that the pork floss from TC was the best, followed by YJJ, DD and HQ. This also shows the potential of machine vision to help people recognize the quality characteristics of pork floss structure.

Catechins affect the oil-holding capacity of meat batters by changing the structure and emulsifying properties of surface proteins at the fat globules.

The effects of different concentrations of catechins on the oil-holding capacity, myofibrillar proteins (MPs) structure and adsorbed properties of interfacial proteins in meat batters were investigated. The addition of 100 mg/kg catechin had no negative effects on the physicochemical properties of meat batter. However, 500 and 1500 mg/kg catechin caused an increase in drip loss and deterioration of dynamic rheological properties; the total sulfhydryl content, surface hydrophobicity and α-helix ratio of MPs decreased significantly (p < 0.05); in meat emulsions, the emulsifying property was reduced, the particle size increased, and less interfacial protein was absorbed on the fat globules. All concentrations of catechins significantly (p < 0.05) inhibited lipid oxidation in meat batters. Medium and high concentrations of catechins induced aggregation of MPs via covalent and noncovalent interactions between MPs and MPs or MPs and catechins, which destroyed the gel and emulsifying property of protein and eventually decrease the oil-holding capacity of meat batters.

Predicting VOCs content and roasting methods of lamb shashliks using deep learning combined with chemometrics and sensory evaluation.

A comparison was made between the traditional charcoal-grilled lamb shashliks (T) and four new methods, namely electric oven heating (D), electric grill heating (L), microwave heating (W), and air fryer treatment (K). Using E-nose, E-tongue, quantitative descriptive analysis (QDA), and HS-GC-IMS and HS-SPME-GC-MS, lamb shashliks prepared using various roasting methods were characterized. Results showed that QDA, E-nose, and E-tongue could differentiate lamb shashliks with different roasting methods. A total of 43 and 79 volatile organic compounds (VOCs) were identified by HS-GC-IMS and HS-SPME-GC-MS, respectively. Unsaturated aldehydes, ketones, and esters were more prevalent in samples treated with the K and L method. As a comparison to the RF, SVM, 5-layer DNN and XGBoost models, the CNN-SVM model performed best in predicting the VOC content of lamb shashliks (accuracy rate all over 0.95) and identifying various roasting methods (accuracy rate all over 0.92).

Raw to charred: Changes of protein oxidation and in vitro digestion characteristics of grilled lamb.

This study aimed to evaluate protein oxidation and in vitro digestion characteristics of lamb that was grilled from raw to charred (0-30 min). Results showed that protein oxidation was aggravated with the time of grilling, indicated by a significant linear increase in carbonyl groups and a linear decrease in sulfhydryl groups. Proteins had the highest simulated gastric and gastrointestinal digestibility at 10-15 min of grilling. Newly formed specific peptides were continuously released during the grilling process. The identified peptides were mainly derived from creatine kinase, phosphoglycerate kinase, actin and myosin light chain. Protein oxidation was closely related to digestive characteristics, and grilling for >15 min would aggravate protein oxidation and reduce its digestibility. Therefore, at 220 °C lamb should not be grilled for longer than 15 min.