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Freezing storage is the most common method of food preservation and the formation of ice crystals during freezing has an important impact on food quality. The water molecular structure, mechanism of ice crystal formation, and ice crystal structure are elaborated in the present review. Meanwhile the methods of ice crystal characterization are outlined. It is concluded that the distribution of the water molecule cluster structure during the crystallization process directly affects the formed ice crystals’ structure, but the intrinsic relationship needs to be further investigated. The morphology and distribution of ice crystals can be observed by experimental methods while simulation methods provide the possibility to study the molecular structure changes in water and ice crystals. It is hoped that this review will provide more information about ice crystallization and promote the control of ice crystals in frozen foods.

The effects of dense phase carbon dioxide (DPCD) pressure and temperature on the activity of cathepsin L in white shrimp (Litopenaeus vannamei) were studied. Meanwhile the effects of DPCD and heat treatment on the activity of cathepsin L were compared. The results of inactivation kinetics showed that under the same treatment temperature, the inactivation effect of DPCD on cathepsin L increased gradually with the increase of pressure and time. The effect of DPCD pressure on the activity of cathepsin L accorded with the first-order kinetic model. Under the same treatment pressure, with the increase of temperature, the inactivation effect of cathepsin L was significant at the initial stage of DPCD treatment (rapid inactivation period), and decreased with the extension of time (stable inactivation period). The effect of DPCD treatment temperature on cathepsin L activity accorded with the first-order kinetic model at 35 °C, and two-stage kinetic model at 40–60 °C. The difference of relative enzyme activity between the two treatments showed that the dependence of DPCD on temperature was greater than that of heat. Ea, F and Ea, S of DPCD were higher than that of heat, which indicated that cathepsin L was more easily inactivated under DPCD treatment.

Improving the printing accuracy and stability of shrimp surimi and finding appropriate printing parameters and suitable thermal processing method can help to develop high value-added 3D printing products of shrimp surimi. It was found that in order to make the 3D printing products of shrimp surimi have higher printing adaptability (printing accuracy and printing stability reach more than 97%), by choosing nozzle diameter of 1.20 mm and setting the printing height of the nozzle to 2.00 mm, the layers of the printed products were better fused with each other, and the printing accuracy of the products could be greatly improved; there was no uneven discharge and filament breakage when the nozzle moved at the speed of 30 mm/s; and the products were internally compact and had good stability when the printing filling rate was 80%. In addition, the deformation rates of steamed, boiled and deep-fried shrimp surimi products were significantly higher than those of oven-baked and microwaved shrimp surimi products (P

The impact of ultrasound thawing (UT) at different power (0 W, 100 W/0.132 W·cm−2, 300 W/1.077 W·cm−2, and 500 W/1.997 W·cm−2, namely WT, UT-100, UT-300, and UT-500) on protein structure, aggregation, and emulsifying properties of common carp (Cyprinus carpio) myofibrillar protein were investigated in the present study. The result showed that the reactive sulfhydryl content, total sulfhydryl content, protein solubility, and absolute potential of UT-300 samples were obviously higher than those of other thawed samples, while the turbidity of UT-300 samples was lower (P

Three-dimensional (3D) printing provides a new method for innovative processing of shrimp surimi. However, there still exists a problem of uneven discharge during the 3D printing of surimi. The effects of different amounts of lard oil (LO), soybean oil (SO), and olive oil (OO) (0%, 2%, 4%, and 6%, respectively) added to shrimp surimi on the 3D printability of surimi were evaluated. The findings showed that with the increase in the added oil, the rheological properties, texture properties, water-holding capacity (WHC), and water distribution of surimi with the same kind of oil were significantly improved; the printing accuracy first increased and then decreased; and the printing stability showed an increasing trend (p < 0.05). The surimi with 4% oil had the highest printing adaptability (accuracy and stability). Different kinds of oil have different degrees of impact on the physical properties of surimi, thereby improving 3D-printing adaptability. Among all kinds of oil, LO had the best printing adaptability. In addition, according to various indicators and principal component analysis, adding 4% LO to shrimp surimi gave the best 3D-printing adaptability. But from the aspects of 3D printing properties and nutrition, adding 4% SO was more in line with the nutritional needs of contemporary people.

The implications of different liquid nitrogen freezing (LNF) temperatures (−35 °C, −65 °C, −95 °C, and −125 °C) on the ice crystal and muscle quality of white shrimp (Litopenaeus vannamei) were investigated in this essay. The results showed that better muscle quality was maintained after LNF treatment compared to that after air blast freezing (AF) treatment. As the freezing temperature of liquid nitrogen decrease, the freezing speed accelerated, with the freezing speed of LNF at −125 °C being the fastest. However, an excessively fast freezing speed was not conducive to maintaining the quality of shrimp. Among all the freezing treatments, LNF at −95 °C led to the lowest thawing losses and cooking losses, and the highest L* values, indicating that LNF at −95 °C could keep the water holding capacity of frozen shrimp better than that with other freezing methods. At the same time, LNF at −95 °C resulted in higher water holding capacity, and hardness values for shrimps than those with other frozen treatments (p < 0.05). In addition, the results of the water distribution of shrimps showed that treatment with a −95 °C LNF reduced the migration rate of bound and free water. Meanwhile, the microstructural pores of shrimps in the −95 °C LNF group were smaller, indicating that the ice crystals generated during −95 °C LNF were relatively smaller than those generated via other frozen treatments. In conclusion, an appropriate LNF temperature (−95 °C) was beneficial for improving the quality of frozen shrimp, and avoiding freezing breakage.

In this article, a total of 22 social workers in Mainland China were interviewed to explore the effectiveness and challenges of providing services to adolescents using digital tools. By addressing the problems like permeable boundaries, perfunctory efforts, threats to implementation fidelity, and inefficient service delivery, we accordingly propose pragmatic recommendations to enhance digital social work practice. [ABSTRACT FROM AUTHOR]

Dense phase carbon dioxide (DPCD) is a new non-thermal method to induce surimi gel. However, the gel quality is affected by many factors, such as DPCD treatment time, temperature, and pressure, which makes it complicated to determine its operating parameters. Box-Behnken and backward linear regression were used to optimize the conditions (temperature, pressure, and treatment time) of DPCD-induced shrimp surimi gel formation, and a model between shrimp surimi gel strength and treatment conditions was developed and validated in the present study. Meanwhile, the heat-induced method was used as a control to analyze the effect of DPCD on the quality of shrimp surimi gel in the present study. The results showed that DPCD treatment affected the strength of shrimp surimi gel significantly, and the pressure of DPCD had the greatest influence on the gel strength of shrimp surimi, followed by time and temperature. When the processing pressure was 30 MPa, the temperature was 55 °C, and the treatment time was 60 min, the gel strength of the shrimp surimi was as high as 197.35 N·mm, which was not significantly different from the simulated value of 198.28 N mm (p > 0.05). The results of the gel quality properties showed that, compared with the heat-induced method, DPCD reduced the nutrient and quality loss of the shrimp surimi gel, and increased the gel strength and gel water-holding capacity. The results of low-field nuclear magnet resonance showed that DPCD increased the binding capacity of shrimp surimi to bound water and immobilized water, and reduced their losses. Gel microstructure further demonstrated that DPCD could improve shrimp surimi gelation properties, characterized by a finer and uniformly dense gel network structure. In summary, DPCD is a potential method for inducing shrimp surimi to form a suitable gel. The prediction model established in this study between DPCD treatment temperature, pressure, time, and gel strength can provide a reference for the production of shrimp surimi by DPCD.

Gallium oxide crystal materials has enormous potential in the fields of power devices and optoelectronics due to its excellent performance and the advantage of being able to grow by melt method. In recent years, numerous experts at home and abroad have also started researching gallium oxide single crystal materials. High quality and low defect gallium oxide single crystal materials are extremely important for subsequent epitaxy and device preparation. At present, the mainstream growth method internationally is edge-defined film-fed growth method (EFG), which has advantages such as short growth cycle, large size, and stable growth. However, there is still great room for progress in crystal defect control. This article focuses on the morphology of corrosion pits in gallium oxide single crystals, and processes samples of gallium oxide single crystals grown by EFG. Corrosion experiments were conducted under different acid and alkali conditions. A detailed introduction was given to the different observed corrosion pit morphologies, and the impact of crystal defects on the corrosion pit morphologies was analyzed. This is of great significance for the future research on the growth mechanism of gallium oxide single crystals and crystal defects. [ABSTRACT FROM AUTHOR]