Freeze-dried restructured strawberry blocks (FRSB) are fascinated by numerous consumers. This study investigated the effect of different hydrocolloid additions, including guar gum, gelatin, pectin, and the composite of the three, on the pore structural properties and the textural quality of FRSB. The composite group of FRSB achieved the smallest pore structure parameters including porosity rate, total volume, average volume, and average area, followed increasingly by the groups of gelatin, guar gum, pectin, and the control, respectively. TPA hardness of FRSB in each group, from high to low, is: composite > guar gum > pectin > gelatin > control (P < 0.05). TPA elasticity, penetration hardness, and penetration work showed significant positive or negative correlation with various pore structure parameters of FRSB. Hydrocolloid addition, especially the composite group, can entitle FRSB with a denser and more stable porous network structure and a better appearance, significantly enhancing their hardness, crispness, and stickiness.

Fresh-cut potato slices are prone to browning. Although freezing is an effective method of preserving food, freezing and thawing cause inevitable damage to potato tissues. This study explored the freeze-protective effects of trehalose and sorbitol under atmospheric pressure impregnation and vacuum impregnation by analyzing their influences on the cell structural and textural characteristics of frozen–thawed potato slices. The results showed that both trehalose and sorbitol can significantly improve the quality of frozen–thawed potato slices. Vacuum impregnation resulted in a higher total sugar content in the impregnated potato slices than atmospheric pressure impregnation (p < 0.05). Sorbitol impregnation significantly reduced cell damage and nutrient loss of frozen–thawed potato slices; specifically, under vacuum impregnation conditions, the juice loss rate and relative electrical conductivity decreased to 7.58 ± 0.47% and 32.90 ± 1.83 mS/cm, respectively. Texture analysis showed that sorbitol impregnation resulted in significantly higher puncture hardness and TPA hardness in frozen–thawed potato slices than trehalose impregnation. Furthermore, observations of cell activity and transmission electron microscopy of potato tissues verified sorbitol’s advantages in maintaining cell structure integrity and reducing ice crystal damage. Hence, sorbitol vacuum impregnation is highly recommended as a pretreatment in potato quick freezing processes. This study provides a theoretical basis and technical support for the improvement of the quality of quick-frozen potato products, and for the later processing and manufacturing of frozen potato slices.

In order to solve problems such as poor applicability of headers, weak separation ability of threshing mechanisms and poor impurity-removal ability of cleaning devices in the existing seed harvest methods of Chinese milk vetch (Astragalus sinicus L.), a combined Chinese milk vetch seed harvester was designed in this paper. The parameters of the key components, such as the flexible anti pod-dropping seedling-lifting header, the longitudinal rod-teeth-type threshing device and the air-sieve-type layered impurity-controlled cleaning device, were designed and optimized. Aiming at reducing seed loss rate, breakage rate and impurity rate of Chinese milk vetch during the mechanical harvesting process, through multi-parameter optimization, the best combination of working parameters was obtained: machine forward speed was 3 km·h⁻¹, rotation speed of the threshing drum was 550 r·min⁻¹, rotation speed of the cleaning fan was 990 r·min⁻¹ and the scale sieve’s opening was 35 mm. Field tests were performed under these parameters, and the results showed that the seed loss rate of Chinese milk vetch was 2.35%, the breakage rate was 0.22% and the impurity rate was 0.51%, which were better than the technical requirements of loss rate and breakage rate less than 5% and impurity rate less than 3% specified in relevant standards. The research results can solve the shortage problem of efficient seed harvest equipment in large-scale planting areas of Chinese milk vetch, and will further help to carry out seed harvest experiments on different varieties of Chinese milk vetch and other green manure varieties in paddy fields.

As an important oil crop in China, peanuts require mechanized sowing to enhance production efficiency. This paper analyzes the influence of peanut seed physical characteristics on the design of seed metering devices and systematically introduces the working principles, advantages, and disadvantages of mechanical (internal cell-fill, cell-wheel, and spoon-wheel types) and pneumatic (air suction, air pressure, and air-blowing types) seed metering devices. This paper reviews the development status of peanut seed metering devices and provides examples of these devices mounted on sowing machines. It is found that European and American researchers mainly conduct research on high-speed pneumatic seed metering devices, and, though China’s peanut seed metering device development has made progress and resulted in products with different technical levels, they still fall short of international advanced products in terms of high-speed seeding capability and seeding accuracy. In the future, research should be strengthened in areas such as the in-depth development of pneumatic seed metering devices, the adaptability of mechanical seed metering devices to high-speed operation, and intelligent monitoring and control systems.

To enhance the operational performance of green manure sowing, seed harvesting, and processing equipment, as well as to obtain the physical characteristic parameters required for equipment simulation analysis, it is necessary to carry out the seed physical properties such as dimensions, bulk density, and frictional characteristics. This study focuses on the main cultivated varieties of green manure in China—milk vetch, hairy vetch, and sesbania—and innovatively proposes three low-cost, convenient, and high-precision experimental methods of geometric size for small-sized seeds. The measured results show that geometric dimensions of the seeds for milk vetch were 2.60mm-3.40mm in length, 1.90mm-2.40mm in width and 0.71mm-0.97mm in height, the pod dimensions of hairy vetch were 23.03mm-32.83mm in length, 7.39mm-9.74mm in width, 4.06mm-6.15mm in height, and seed diameters were 3.04mm-4.10mm, the seed dimensions of sesbania were 3.81mm-4.29mm in length, 1.98mm-2.37mm in width, 1.85mm-2.08mm in height. Using Python programming language and open-source AI algorithms, we innovatively developed an image-based seed counting experimental method. This cost-effective approach requires no specialized instruments while significantly saving time and labor. Based on the counting results, the thousand-seed weights of milk vetch, hairy vetch, and sesbania seeds were determined to be 3.40g, 26.50g and 15.58g, with respective seed moisture contents of 7.18%, 9.81% and 8.73% at the time of measurement. The instruments and methods for measuring bulk density and angle of repose of green manure seeds were defined. The bulk densities of milk vetch, hairy vetch, and sesbania seeds were determined to be 732 g/L, 761 g/L and 845 g/L, by using the electronic grain densitometer. Meanwhile, the angles of repose of milk vetch, hairy vetch, and sesbania seeds were determined to be 31.66°, 28.15°and 29.82°, by using the angle of repose tester. Based on the principle that the indexing head can accurately determine the angle, the sliding friction angles of milk vetch, hairy vetch, and sesbania seeds were determined to be 25.85°, 23.55°and 24.03°, by using the di-viding head. The testing methods developed in this study, along with the results of measuring the physical properties of green manure seeds, provide valuable reference data for the measurement of the physical properties of small-seeded crop (e.g., green manures) as well as other small or irregularly-shaped particles.

To improve the performance of green manure sowing and processing equipment, it is necessary to investigate the physical properties of seeds, including their dimensions, bulk density, and frictional characteristics. Focusing on the main cultivated varieties of green manure in China—milk vetch, hairy vetch, and sesbania—this study proposes three low-cost, convenient, and high-precision experimental methods to measure the geometric size of small seeds. The measured results show that the milk vetch seeds were 2.60–3.40 mm in length, 1.90–2.40 mm in width, and 0.71–0.97 mm in height. The hairy vetch pods were 23.03–32.83 mm in length, 7.39–9.74 mm in width, and 4.06–6.15 mm in height, and the seeds were 3.04–4.10 mm in diameter. The sesbania seeds were 3.81–4.29 mm in length, 1.98–2.37 mm in width, and 1.85–2.08 mm in height. The thousand-seed weights of milk vetch, hairy vetch, and sesbania seeds were 3.40 g, 26.50 g, and 15.58 g, with moisture contents of 7.18%, 9.81%, and 8.73%, respectively. The bulk densities of milk vetch, hairy vetch, and sesbania seeds were 732 g/L, 761 g/L, and 845 g/L. The angles of repose of milk vetch, hairy vetch, and sesbania seeds were 31.66°, 28.15°, and 29.82°, measured using an angle-of-repose tester. Sliding friction angles of 25.85°, 23.55°, and 24.03° for milk vetch, hairy vetch, and sesbania seeds were obtained using a dividing head. These methods and results provide valuable references for the measurement of the physical properties of small-seeded crops (e.g., green manures) as well as other small or irregularly shaped particles.