Heat and mass transfer, shrinkage, and thermal protein denaturation of kuruma prawn (Marsupenaeus japonicas) during water bath treatment: A computational study with experimental validation

TMT proteomics establishes correlations between solar drying and quality modifications in Penaeus vannamei

This study investigated proteomic changes in Penaeus vannamei in half-dried and dried shrimp using tandem mass-tag technology. After performing the drying treatment, the tandem mass-tag results revealed 1,162,306 spectra, 2997 quantifiable proteins, and 72 differentially expressed proteins (DEPs) compared with that in the untreated group. A total of 29 DEPs were found in the half-dried shrimp, while 49 DEPs were found in the dried shrimp. Bioinformatic analyses based on Gene Ontology term enrichment, Kyoto Encyclopedia of Genes and Genomes pathway enrichment, and protein-protein interactions showed that the DEPs were primarily involved in protein structure and fat metabolism. A correlation analysis between the DEPs and quality indicators showed that 45 DEPs were significantly associated with shrimp quality traits, with certain proteins potentially representing markers of color and texture. Of these, arthrodial cuticle protein AMP16.3 might be a protein marker for color, while heat shock protein 21, WH2 domain-containing protein, and myosin heavy chain 1 might be markers of shrimp muscle textural properties. These results provide a systematic understanding of the quality difference between half-dried and dried P. vannamei from the perspective of proteomics and have potential scientific significance and practical value for improving the quality of dried products.

Numerical Investigation of the Deformable Porous Media Treated by the Intermittent Microwave

A 2D axi-symmetric theoretical model of dielectric porous media in intermittent microwave (IMW) thermal process was developed, and the electromagnetic energy, multiphase transport, phase change, large deformation, and glass transition were taken into consideration. From the simulation results, the mass was mainly carried by the liquid water, and the heat was mainly carried by liquid water and solid. The diffusion was the dominant mechanism of the mass transport during the whole process, whereas for the heat transport, the convection dominated the heat transport near the surface areas during the heating stage. The von Mises stress reached local maxima at different locations at different stages, and all were lower than the fracture stress. A material treated by a longer intermittent cycle length with the same pulse ratio (PR) tended to trigger the phenomena of overheat and fracture due to the more intense fluctuation of moisture content, temperature, deformation, and von Mises stress. The model can be extended to simulate the intermittent radio frequency (IRF) process on the basis of which one can select a suitable energy source for a specific process.

Effects of NaCl content and drying temperature on lipid oxidation, protein oxidation, and physical properties of dry-cured chicken

This study aimed to investigate the effects of different NaCl content and drying temperatures on the lipid oxidation, protein oxidation, and physical properties of dry-cured chicken. In the final product, lipid oxidation, protein oxidation, and physical properties were significantly affected by NaCl and temperature. Increased NaCl content and temperature led to significantly increased level of indicators including conjugated diene, thiobarbituric acid reactive substances, and carbonyl contents (P < 0.05). Conversely, the sulfhydryl contents and surface hydrophobicity significantly decreased (P < 0.05). Results of sodium dodecyl sulfate polyacrylamide gel electrophoresis further indicated that NaCl and temperature affected protein oxidation and degradation. According to the drying curve, the main factor affecting the drying time was the drying temperature and a slower rate of moisture loss occurred in samples with higher NaCl content. Moreover, due to the effects of temperature on lipid and protein oxidation and moisture diffusion, the hardness and shrinkage ratio increased with temperature. PRACTICAL APPLICATION: Dry-cured chicken is a kind of air-dried meat product. During actual production of dry-cured chicken, its physicochemical characteristics (e.g., lipid and protein oxidation and texture) are affected by NaCl content and drying temperature. In this study, the NaCl content and drying temperature were found to promote lipid and protein oxidation and have significant effects on texture properties. Therefore, the NaCl content and drying temperature should be controlled to improve the quality of dry-cured chicken.