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The nutritional quality and safety of fruit and vegetable products are the urgent problems and research hotspots in the processing field. High-pressure homogenization, a non-thermal processing technology, can maximize the preservation of the nutritional quality, color and flavor of fruit and vegetable products while sterilizing and inactivating enzymes, and is expected to replace thermal processing technology. This article reviews the effects of high-pressure homogenization on the color, stability and nutritional components of fruit and vegetable products, and summarizes the killing effect and mechanism of high-pressure homogenization on microorganisms. It discusses the prospects and challenges of high-pressure homogenization technology in the application of fruit and vegetable products from two aspectsof equipment and technology, providing a theoretical reference for the innovation of high-pressure homogenization technology and equipment.

Henan encountered a multi-stage severe convective weather event (hereinafter referred to as "6.13" event) accompanied by local tornado on 13 June 2022. Using conventional observation data, regional automatic weather station data, satellite cloud images, Doppler weather radar data, ERA5 reanalysis data and other relevant data, we conducted an analysis on atmospheric circulation environment and the evolution characteristics of mesoscale systems for the "6.13" event. In addition, we discussed the initiation and maintenance mechanisms of convection in the different periods of this event and the radar characteristics of the local tornado in Puyang of Henan. Results are as follows. (1) The "6.13" event occurs under the northwest airflow behind the northeast cold vortex trough, and it is characterized by wide impact range, long duration and multiple types of disaster weather. (2) Radar detection results show that the severe convective systems in the "6.13" event passed through Henan in three periods one after another, and strong echoes in each period lasts for 8-9 hours, with the moving speed of 30-50 km·h-1. Most of the severe convective systems are multi-cells that all moved from northwest to southeast, with some of their areas overlapping under the guidance of northwest airflow. (3) Maintenance of the strong conditional instability and the moderate to strong vertical wind shear over Henan is an important cause for multi-stage severe convective weather in the "6.13" event lasting for a long time. The first period of local severe convection in Henan is mainly triggered by the convergence line or convergence center in the boundary layer formed by the combined effect of daily changes of wind field, local cold air activity, topographic distribution, while the second and third periods of severe convection are triggered by the gust front or outflow boundary accompanied by the surface mesoscale thunderstorm high formed by the strong developing convection systems in the surrounding area in the previous period or the same period. (4) The local tornado in Puyang is generated by a rapidly developing supercell storm. The hook echo and mesoscale cyclonic vortex appear 12 minutes after this supercell storm, and the tornado vortex characteristics (TVS) appear 18 minutes later. The hook echo and mesoscale cyclonic vortex are 6 minutes ahead of the occurrence of tornado, which can provide a reference information for early warning local tornadoes.

High-pressure homogenization has been extensively studied for its excellent homogenization effect and the prospect of continuous liquid food production, but its sterilization ability still needs to be improved. In this study, we replaced the homogenization valve with two opposing diamond nozzles (0.05 mm inner diameter) so that the fluid collided at high velocity, corresponding to high-pressure micro-fluidization (HPM). Moreover, HPM treatment significantly inactivated Staphylococcus aureus ~7 log in the liquid with no detectable sub-lethal state at a pressure of 400 MPa and a discharge temperature of 50 °C. The sterilization effect of HPM on S. aureus subsp. aureus was attributed to a significantly disrupted cell structure and increased membrane permeability, which led to the leakage of intracellular proteins, resulting in bacterial death. At the same time, HPM treatment was able to significantly reduce the ability of S. aureus subsp. aureus to form biofilms, which, in turn, reduced its virulence. Finally, compared to the simulated system, more effective sterilization was observed in apple juice, with its color and pH remaining unchanged, which suggested that HPM can be used to process other liquid foods.