A novel and promising reheating method has been explored to address the issue of meat consumption and safety quality degradation after reheating. This study compared the effects of boiling, steaming, microwaving, stirfrying, and microwave synergistic steam (MW + ST) reheating on the flavor and advanced glycation end products (AGEs) of braised pork. The results demonstrated that MW + ST was effective in reducing AGEs formation with an N epsilon-carboxymethyllysine (CML) content of 4.21 mg/kg and a fluorescent AGEs level of 208.3 AU, which only increased 17.13 % and 1.98 %, respectively, compared with the content before reheating. This can be attributed to the high moisture content (49 %) and immobilized water proportion (92.65 %) maintained by MW + ST, resulting in the reduced accumulation and production of AGEs precursors (Schiff base and glyoxal) by suppressing lipid oxidation, protein oxidation, and the Maillard reaction. Additionally, the electronic nose and electronic tongue results showed that MW + ST was closest to the original odor of braised pork and exhibited excellent taste characteristics. Overall, the high sensory scores and safety qualities of the MW + ST suggested that it promises to be a new way of reheating for consumers and food distribution companies compared to conventional reheating methods.

Maintaining low-energy consumption and improving the quality of frozen pork contribute to the sustainability of the meat industry. This study used a 23.5 % sodium chloride (NaCl) solution as the control refrigerant (NIF). It investigated the effects of substituting 10 % of NaCl in the refrigerant with three amino acids (l-lysine, l-proline, or l-arginine) on energy consumption and pork quality improvement in contact immersion freezing. Results indicated that l-proline among three amino acids could mitigate the increase in specific heat capacity, the decrease in thermal conductivity, and the unfrozen water content of pork caused by the reduction of NaCl via mitigating the increase in specific heat capacity, the decrease in thermal conductivity, and the thermal diffusion coefficient of the refrigerant, thus maintaining the freezing energy conservation and efficiency (reduced freezing time) of the NIF group. The incorporation of l-proline also effectively reduced NaCl infiltration into the pork and improved its color quality. This study provides a new refrigerant for contact immersion freezing in the meat industry, offering low-energy consumption and improved frozen meat quality.

Bacteria and endogenous enzymes generate volatile organic compounds (VOCs), which are posited to be the primary source of undesirable flavors in spoilt pork. Headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) was employed to assess the fluctuations in VOC concentrations in pork stored under tray packaging at 6–8 °C for 10 days, while total volatile basic nitrogen (TVB-N) and total viable counts (TVCs) were used to determine the quality of the pork. During storage, TVCs steadily increased, reflecting the growth of spoilage-related microorganisms, while TVB-N levels surpassed the spoilage threshold early, indicating an acceleration of the degradation process. Nine VOCs associated with pork spoilage were found by partial least squares discriminant analysis (PLS-DA), fold change (FC), and t-tests. The substances comprised ethyl acetate, acetoin, 3-methyl-1-butanol, 3-methylbutanal, 1-octen-3-ol, hexanal, vinyl acetate, 2-methylaziridine, and heptanal. A univariate linear regression analysis revealed a strong positive correlation (p < 0.001) between the gaseous total volatile basic nitrogen (G-TVBN) and the storage duration. Given that G-TVBN accurately reflects changes in pork freshness and the progression of spoilage, these results highlight the potential for dynamically monitoring the freshness and spoilage processes of pork.

Maintaining meat quality during frozen storage poses a significant challenge for the food industry. This study utilized a 23.5 % sodium chloride (NaCl) solution as the control refrigerant (NIF) and examined the effects of substituting 10 % of NaCl in the refrigerant with L-proline and/or L-lysine on the storage (-20 degrees C) quality and oxidation stability of frozen pork via contact immersion. Results revealed that compared to NIF, L-lysine and the combination of L-lysine with L-proline could reduce the TBARS values of the frozen pork by 44.81 % and 39.30 %, the carbonyl contents of MP by 34.63 % and 43.34 %, and increase the total sulfhydryl contents of MP by 102.31 % and 96.69 % at 9 weeks of frozen storage, respectively, which indicated that L-lysine and its combination were effective in reducing the oxidation of lipids and proteins in frozen pork during storage. This was achieved by slowing the decline in the activities of catalase, superoxide dismutase, and glutathione peroxidase, minimizing mitochondrial damage, and decreasing reactive oxygen species content. Consequently, this approach enhanced the a* value of frozen pork while reducing its NaCl content. This study offers a novel approach for the meat industry, effectively controlling oxidation and improving the quality of frozen pork during storage.

With an increasing emphasis on environmental protection and sustainability, natural polymers like proteins and polysaccharides are being utilized more frequently in the development of biodegradable food packaging. However, the limited properties of these biopolymers have restricted their widespread applicability within the food industry. To address this issue, eugenol-loaded zein nanoparticles (ZE NPs) were incorporated into pea starch/soy protein-based films, and their effect on the physicochemical properties of these films were investigated. The ZE NPs exhibited high compatibility with the pea starch-soy protein isolate (PES/SPI) matrix, enhancing the structural properties of the films by forming hydrogen bonds between the nanoparticles and the biopolymer network. Incorporating the nanoparticles enhanced the mechanical properties, thermal stability, ultraviolet shielding, surface hydrophobicity, and moisture barrier performance of the films. Furthermore, the films containing ZE NPs exhibited significant antioxidant and antibacterial activity, suggesting their potential application as preservatives in active food packaging materials. In conclusion, the incorporation of ZE NPs significantly enhanced the performance of PES/SPI-based films, which should expand their application as food packaging materials.

This paper was concerned with the detection of hazardous bone fragments embedded in lean pork slices (LPSBFs) by comparing the pixel area of bone regions segmented from single -band image. All images were collected using a Videometer A/S multispectral imaging system with 19 bands (405 - 970 nm). An area library of bone regions was established by processing 60 images captured from LPS-BFs and the minimum value of the library was defined as a boundary point for judgement. The accuracy of 90 % for 120 test samples (60 LPSs and 60 LPSBFs) was achieved and all results could be visualized for monitoring the geometrical morphology of bones. Results of satisfactory identification of bone fragments embedded in LPSs indicated that image features at singleband could serve as a feasible approach for online industrial applications.

Background The formation, morphology, and properties of the layers in pearl have intrigued scientists and artisans for centuries. Nacre, formed within the shells of mollusks, have a unique laminated composite structure, characterized by alternating layers of organic substances and calcium carbonate crystals. Understanding the intricacies of pearl formation has implications beyond aesthetic appreciation. Recently, there has been growing interest in exploring the potential applications of pearl-inspired materials in various fields, including the food industry. Scope and approach This article begins by reviewing the formation, structure, and mechanical properties of pearl layers, with the aim of elucidating how biomimetic functional materials can be assembled for food applications. The potential of various fabrication approaches, including self-assembly, biomineralization, 3D printing, and vacuum filtration for mimicking the complex structure of natural pearls are discussed. The potential application of these pearl-inspired biomimetic materials as protectants and sensors in food packaging is then highlighted. Key findings and conclusions Studies indicate that nacre-inspired materials can be fabricated to possess optical properties, mechanical strength, barrier capabilities, and hydrophobicity akin to those found in natural pearls. Advanced fabrication technologies allow precise control over the properties of these materials. As a result, novel bio-inspired materials can be created that may be used in smart packaging materials, e.g., as humidity sensors, freshness detectors, or anti-counterfeiting labels to enhance food quality, safety, and authenticity.

The feasibility of acoustic vibration signals acquired by a self-made device was assessed as a non-destructive technology for identifying moldy kernels of in-shell hickory nuts (MK-IHNs). Twenty-two acoustic features extracted from time-domain and frequency-domain signals were used to establish a precious model for classifying MK-IHNs and healthy kernels of in-shell hickory nuts (HK-IHNs). Based on a combination of time-domain and frequency-domain features, an optimized LIB support vector machine (Lib-SVM) model was obtained with accuracy of 91.67% for identifying MK-IHNs. Some physical parameters of hickory nuts such as weight and bulk density were significantly correlated with most of the acoustic features (P < 0.05). Moreover, the microstructures of HK-IHN and MK-IHN shells, whatever outside surfaces or cross-sections, were obviously different. It follows then that the physical forms and structures of hickory nuts would play important roles in building a reliable model for identifying MK-IHNs based on acoustic vibration technology. Results of satisfactory proved that the acoustic vibration technology combined with Lib-SVM method could serve as a feasible approach for non-destructive damage identification of MK-IHNs.

挥发性盐基氮(total volatile basic nitrogen,TVB-N)是衡量臭鳜鱼新鲜度的一项重要指标,而现有检测方法存在速度慢、对样品破坏性强的局限性.为实现TVB-N快速无损检测,该文利用气相傅里叶变换红外光谱获取不同贮藏条件下臭鳜鱼挥发物的光谱信息,采用高斯滤波、稳健局部加权回归(robust locally weighted regression,RLWR)、小波阈值去噪、模拟退火-偏最小二乘(simulated annealing-partial least squares,SA-PLS)等方法进行光谱预处理,偏最小二乘回归和支持向量回归算法构建预处理光谱与TVB-N之间的关联性模型.结果表明,与其它模型相比,经RLWR结合SA-PLS选择的特征波长光谱可建立最优预测模型,其决定系数(decision coefficient,R2p)和相对预测误差分别为0.9428和 4.0050,具有较高的精准度与鲁棒性.

This research investigates the antibacterial potential of plant essential oil components including thymol, carvacrol, citral, cinnamaldehyde, limonene, and β-pinene against Salmonella Enteritidis (S. Enteritidis). Through the determination of minimum inhibitory concentration, three kinds of natural antibacterial agents with the best inhibitory effect on S. Enteritidis were determined, namely thymol (128 μg/mL), carvacrol (256 μg/mL), and cinnamaldehyde (128 μg/mL). Physical, chemical, microbial, and sensory characteristics were regularly monitored on days 0, 2, 4, and 6. The findings of this study reveal that both thymol at MIC of 128 μg/mL and carvacrol at MIC of 256 μg/mL not only maintained the sensory quality of chicken, but also decreased the pH, moisture content, and TVB-N value. Additionally, thymol, carvacrol and cinnamaldehyde successfully inhibited the formation of S. Enteritidis biofilm, thereby minimizing the number of S. Enteritidis and the total aerobic plate count in chicken. Hence, thymol, carvacrol, and cinnamaldehyde have more effective inhibitory activities against S. Enteritidis, which can effectively prevent the spoilage of chicken and reduce the loss of its functional components.

The pea protein isolate nanoparticles/octenyl succinic anhydride linear dextrin (PPINs/OSA-LD) composite particles were fabricated by heating at acidic condition. Heating treatment not only made OSA-LD dissolve, but also promoted the hydrophobic interactions between PPINs and OSA-LD. With the increase of OSA-LD content, the average diameter of composite particles decreased due to the avoidance of hydrophobic aggregation between PPINs during heating, and the composite particles became more compact and regular. The high internal phase emulsions (HIPEs) stabilized by composite particles exhibited smaller droplet size, higher viscosity and modulus attributing to the formation of denser interfacial layer. The results of low field nuclear magnetic resonance proved that the HIPEs stabilized by composite particles showed more uniform distribution of water and oil. This work provided a facile method to fabricate composite particles, which had excellent capacity to stabilize the HIPEs.

The feasibility of multispectral imaging in the range of 405-970 nm was assessed as a rapid and non-destructive technique for classifying lean pork slices (LPSs) and LPSs contained bone fragments. The region-of-interest (ROI-2) extracted by feature image at 700 nm played a key role to improve the precision of classification models. Seven key wavelengths (450, 470, 645, 660, 700, 780 and 970 nm) were identified using successive projections algorithm. Compared with the models established by the whole spectra, the spectral data extracted from ROIs-2 at the key wavelengths gave the highest classification of 100% for test set. A best performance for identifying the bone fragments embedded in LPSs was achieved by linear discriminant analysis model with misclassification rate less than 1% for training and test sets based on the key wavelengths. Results of satisfactory identification and visualization of bone fragments indicated that multispectral imaging could serve as an online approach for potential industrial applications.

Frozen-thawed pork was widely used as a raw material for processing boneless meat products. The hazardous bone fragment (1-2. 5 cm) embedded in the pork can risk processing equipment and consumer health. Therefore, it is necessary to study the feasibility of multispectral imaging technology (405 similar to 970 nm) for rapid and non-destructive identification of the bone fragments embedded in frozen-thawed pork. In this work, 195 lean pork slices (LPSs) were prepared into 65 samples of boneless LPSs, 65 samples of bone fragments embedded in the surface of LPSs and 65 samples of bone fragments embedded in the inner of LPSs, and then the multispectral images of them were captured after freeze-thaw treatment. These images were segmented by canonical discriminant analysis (CDA) and converted into two types of regions of interest(ROIs-1 and ROIs-2), then extracted their spectral and image information. Finally, the identification models of hazardous bone fragments embedded in the frozenthawed LPSs were established by support vector machine (SVM) and neural network (NN). The results showed that the whole spectra extracted from ROIs-2 had better identification ability of bone fragments than that extracted from ROIs-1 and could be used to establish SVM and NN models with 100% accuracy, indicating that the region segmentation was closely related to model accuracy. The bone fragments in pork could be identified with 100% accuracy using the spectra extracted from ROIs-2 at six key wavelengths (505, 590, 700, 850, 890 and 970 nm) that were selected by successive projection algorithm (SPA) implying that the testing efficiency was further improved. The image information had a significant advantage because it could establish the SVM model with 93. 8% accuracy and the NN model with 93. 33% accuracy for identifying the bone fragments that were lower than those established by the spectral information and obtain visible results. In conclusion, the bone fragments embedded in the frozen-thawed pork could be precisely identified based on multispectral imaging technology, which would provide a theoretical basis for industrial online detection.

Pickering emulsions stabilized by zein/carboxymethyl dextrin nanoparticles were added to the kappa-carrageenanbased gel matrix to prepare emulsion gels via EDC - induced covalent crosslinking. Texture, WHC and freeze-thaw stability of the emulsion gels increased after crosslinking. The Confocal laser scanning microscope and SEM suggested that droplet clusters could be observed in gel with higher concentration of emulsion. The rheological measurements indicated that the viscosity and gel-like structure were relied on crosslinking agent and emulsion concentration. The photothermal stability of curcumin was significantly enhanced after crosslinking. In addition, in vitro digestion study suggested that the bioaccessibility of curcumin in emulsion gel crosslinked was lower compared to emulsion gel without crosslinking agent. These studies might facilitate the preparation of emulsion gels with excellent stability for bioactive compounds delivery in food and pharmaceutical applications.

Abstract Salmonella is considered one of the major foodborne pathogens associated with severe infections. Little attempt has been focused on the distribution of Salmonella in retail meats and the analysis of its phenotypic characteristics in Anhui Province. The aim of this study was to characterize the prevalence of Salmonella serovars, antimicrobial susceptibility, antimicrobial resistance genes, and virulence genes in Salmonella recovered from retail meats in Anhui, China. Out of the 120 samples collected from supermarket chains and open‐air markets, 16 samples (13.3%) were positive for Salmonella, of which Salmonella enterica serovars Enteritidis and Typhimurium were the common serotypes. Significant differences in incidence were found between supermarket chains and open‐air markets (p < 0.05). Overall, all 16 isolates were resistant to at least two tested antimicrobials, while 12 isolates showed multiple antimicrobial resistant phenotypes. High resistance was observed for ampicillin (87.5%), doxycycline (75.0%), and tetracycline (62.5%). The sul2 was detected in all isolates, and the aac(6′)‐Ib‐cr (93.8%) and the tetA (81.3%) were predominant in 10 resistance genes conferring five classes of antimicrobials. In addition, the correlation between resistance phenotypes and genes of tetracyclines and aminoglycosides was more than 80%. Interestingly, all the Salmonella isolates contained the genes mogA, mgtC, sopB, and spvB, whereas the siiE was variably represented. The findings in this study showed high prevalence, antimicrobial resistance, and the existence of virulence genes, suggesting that effective measures are required to ensure microbial safety from retail meats.

This study was designed to evaluate changes in color following pork chop supplementation with porcine hemin, astaxanthin and paprika red in response to repeated freeze-thaw processes. Surface color analyses revealed that hemin significantly enhanced the appearance of the pork chops (P < 0.05), and the coloring efficiency of 0.10% hemin was similar to that of 0.20% astaxanthin and 0.08% paprika red. Sensory evaluations conducted on both raw and fried chops showed that hemin and astaxanthin significantly enhanced the overall acceptability of the chops before and after cooking. The color stability of the pork chops was also evaluated, and the results suggested that the hemin-colored chops were the most stable among the three, upon repeated freeze-thaw cycles. The electronic nose showed that the odor of the hemin-colored samples after 0, 3, and 7 freeze-thaw cycles was better than that of the other two groups. In conclusion, hemin may be a superior supplement for the large scale preparation of prepared pork chop.

通过采用KCl和CaCl2部分替代NaCl,开发低钠盐板鸭的加工工艺.单因素试验研究了加盐配方、腌制时间、风干时间和风干温度对板鸭感官品质的影响,在此基础上通过正交试验优选了低钠盐板鸭的加工工艺.结果表明,复合盐替代加工低钠盐板鸭的最佳工艺条件为加盐配方60％NaCl+40％KCl、腌制时间48 h、风干时间84 h和风干温度12℃.

This research aimed to reduce the loss of juiciness and textural properties of prepared beef steak during freezing by applying low voltage electric field (LVEF). Results showed that LVEF assisted freezing (LVEFF) speeded up the freezing process by 29.8% of the steak at the layer spacing of 30 cm (LVEFF-30). And LVEFF-30 efficiently reduced the press loss and thawing loss of the prepared steak by 21.2% and 47.4%, respectively. Textural analysis showed that LVEFF could enhance the hardness and tenderness of the thawed steak comparing with AF (air-blast freezing). Analysis of the size and distribution of ice crystals in muscle revealed that LVEFF could promote more uniform crystal nuclei and more rapid ice nucleation than AF. Low field nuclear magnetic resonance showed that LVEFF reduced the migration of immobilized water to free water, where LVEFF-30 was the most efficient manner. In conclusion, LVEFF could efficiently reduce the juiciness and textural loss of prepared beef steak during freezing comparing with AF. Industrial relevance: The juiciness and textural properties may seriously lose in traditional freezing method (AF), which reduces the quality of the prepared meat products and are unfavorable to consumers. LVEF represents a safe and energy-efficient physical processing technique based on electrostatic field, which has never been utilized in freezing meat products. Herein, the effect of LVEF on the juiciness and textural loss of prepared beef steak during freezing and the underlying mechanism will be discussed. The results will provide guidance for utilizing LVEF in the freezing storage and transport of prepared beef steak.

To improve the industrial yield of sodium-reduced meat products, we present a feasible method by adjusting water-immersion cooling temperatures to decrease the water loss of pork sausage during processing. The present results showed that the moisture retention capacity of sodium-reduced pork sausages (SRPS) cooled by the temperatures of 15–20 °C was larger than that of 0–10 °C. The higher cooling temperatures, especially at 20 °C, could change the movement and population of proton of inner water, decrease syneresis and facilitate the formation of homogenous cross-linked network, thus increasing the moisture retention of SRPS. Results of this work indicated that the control of cooling temperature of sodium-reduced sausages after cooking could serve as a feasible approach for improving the economic benefits and quality characteristics of the final products.

Three coagulase-negative staphylococci (CNS) species were investigated for gene expression of nitric oxide synthase (NOS) and the ability of nitrosomyoglobin (NO-Mb) formation in a dry sausage model without nitrite addition. The expression of nos gene was systematically proven from DNA to RNA to protein, and nitric oxide (NO) generation was also directly detected. In the dry sausage model system, the redness (a*-values) of samples inoculated with the three CNS species were higher than those inoculated with Pediococcus pentosaceus and the control (P < 0.05). The results from UV-vis and electron spin resonance spectroscopies revealed that pentacoordinate NO-Mb was formed in the sausages with either CNS or nitrite added. The sausage inoculated with Staphylococcus vitulinus had the highest NO-Mb content among the CNS-treated sausages. Dimer interface residues and phosphorylation sites of NOS in. itulinus differ from the other two CNS species as revealed by amino acid sequences, which may be responsible for the different catalytic activities.