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The finned surface can increase the specific surface area, which could enhance the boiling efficiency of the working medium to realize the enhancement of heat transfer performance. This research adopted a step punching method to form a radial microgroove structure on the surface of a copper plate. The scanning electron microscopy analysis indicates that when the pressed metal is in the deformation range, it will flow under extrusion and is subject to the reaction force from the metal outside the deformation range, so a micro-finned structure nearby the punching tool is formed. And the deformation area of the formed microgroove is higher than the workpiece’s primitive surface. The relationships of the punching interference length L i with θ c , a c , and α pt are analyzed; and the influence of forming parameters on the groove surface morphology as well as the relationships among these parameters are discussed. When the punching depth a c is 0.3 mm and the punching feeding angle θ c is 2°–4°, the finned surface of the radial V-shaped microgrooves can be obtained.

Summary: A combination of high‐pressure processing (HPP, 200 MPa, 10 min) and CaCl2 (0.2%, w/w) on the cooking loss (CL), expressible moisture (EM), textural properties (hardness, springiness, cohesiveness, chewiness and firmness) and sensory attributes of reduced‐sodium (1.25% NaCl) chicken meat batters (RCMB) was investigated. The results revealed that combining HPP with CaCl2 significantly decreased EM, elevated sensory properties and acted synergistically in reducing CL and improving hardness, chewiness and firmness, which enabled RCMB to obtain quality characteristics similar to those with high salt (2.5% NaCl) content. These changes brought about by combined HPP and CaCl2 could be attributed to increased apparent viscosity and proportion of immobilised water, enhanced rheological (elastic) properties and a denser, homogeneous protein gel network with evenly dispersed small fat globules. It is interesting to take advantage of the synergy between moderate HPP and low concentrations of CaCl2 to develop meat products with reduced sodium content. [ABSTRACT FROM AUTHOR]

Summary: The water holding capacity (WHC) of sodium‐reduced (0.3 m sodium chloride, corresponding to the salt percentage (w/v) of 1.755%) myofibrillar protein (MP) gel in response to combined calcium chloride (CaCl2, 20, 60, 100 mm) and high‐pressure processing (HPP, 200 MPa, 10 min) was investigated. The results showed that 200 MPa + 20 mm CaCl2 synergistically increased the WHC of MP gel via reducing particle size of MP solutions, strengthening hydrogen‐bonding and disulphide‐bonding, promoting formation of β‐sheet and uncoiling of α‐helix, exposing tryptophan residues, enhancing hydrophobic interactions of aliphatic residues and forming a compact and continuous networked gel structure. However, high concentrations (≥60 mm) of CaCl2 could attenuate the enhancing effects of HPP on the WHC by inducing decreased hydrogen bonds, fewer tryptophan residues exposed and coarser and aggregated gel structures with large cavities. Therefore, a combined moderate HPP and low concentration of CaCl2 is a potential alternative for developing sodium‐reduced meat products. [ABSTRACT FROM AUTHOR]

The improvement mechanism of high pressure processing (HPP, 100-300 MPa, 10 min) on the gelation properties of reduced-sodium (0.3 M sodium chloride) myofibrillar protein containing 20 mM CaCl 2 (MP-Ca) were explored. The results showed that the water holding capacity (WHC) and strength of MP-Ca gel reached the maximum values under 200 MPa. This was attributed to substantial solubilization of myosin heavy chain and actin, a decreased protein aggregation ability and the exposure of both tyrosine and tryptophan residues resulting from the unfolding of the protein tertiary structure. However, 300 MPa induced the hydrophobic rearrangement of MP and the disulfide cross-linking of the myosin S-1 subfragment, leading to the formation of large protein aggregates and decreased solubility of MP, thus resulting in a weaker gel with a reduced WHC. Therefore, moderate HPP (approximately 200 MPa) and low concentrations of CaCl 2 could potentially improve the gelation properties of reduced-sodium meat products., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)