Spray Time Research Articles

Religious Attitudes Towards Ethical Problems in the Greenhouse Vegetable Cultivation in Türkiye

The main purpose of this study is to determine the level of influence of religious sensitivity regarding the ethical problems of greenhouse vegetable cultivation and to investigate the possibility of religious contribution to the solution of ethical problems arising on the ground of greenhouse cultivation. Religious sensitivities of greenhouse vegetable growers, where physical conditions are controlled and industrial production is dominant, were analyzed through main categories such as daily life and religion, pesticides and health, genetics and nature. The study aims to provide a background reading of specific moral issues in the context of religious sensitivity analysis.
 The data were collected by means of questionnaires arranged in accordance with the purpose, by interviewing 430 producers growing vegetables in greenhouses within the borders of Antalya province located in the Mediterranean Region of Turkey. An index was created to analyze the religious mentality of greenhouse vegetable growers and to show their religious sensitivity levels in solving ethical problems. The characteristics of the producers, their attitudes and behaviors in the production process are known as the factors that affect the religious sensitivity towards the ethical problems of greenhouse vegetable cultivation. These factors were tested with a multiple linear regression model whose dependent variable was the religious sensitivity index.
 Producers who think that they are praying while doing their work in the greenhouse vegetable production process and quit their job to perform the Friday Prayer have been found to be more religiously sensitive to ethical issues than other producers. Religion was found to be important in the daily lives of the producers and it was stated that religion affected behaviors on the basis of mentality. The level of religious sensitivity was determined to be quite high, that a mistake they made in greenhouse vegetable growing activities would be punished not only in the hereafter but also in this world. This situation shows that in order to overcome the ethical problems in greenhouse vegetable cultivation, the strategies to be followed should be considered within the religious framework. In the linear regression model, it can be said that the producers with high school and undergraduate education levels have higher religious sensitivity to the ethical problems of greenhouse vegetable cultivation compared to the producers with primary education level. Certain experiences of greenhouse vegetable growers may be linked to their general religious attitudes. In this respect, it can be said that the religious sensitivity of the producers, who have been doing greenhouse cultivation for a long time, towards ethical problems is more important than the less experienced ones.
 The religious sensitivity index for greenhouse vegetable cultivation is the first in the literature. The religious sensitivity index, whose relationships are analyzed in the form of daily life and religious perception, genetics and nature, greenhouse vegetable production and the hereafter, chemical spraying and health, non-compliance with the spraying time and seeing the return in life, moral consistency and market conditions, seems to have the potential to guide further studies.

Monitoring of Cotton Boll Opening Rate Based on UAV Multispectral Data

Defoliation and accelerating ripening are important measures for cotton mechanization, and judging the time of defoliation and accelerating the ripening and harvest of cotton relies heavily on the boll opening rate, making it a crucial factor to consider. The traditional methods of cotton opening rate determination are time-consuming, labor-intensive, destructive, and not suitable for a wide range of applications. In this study, the relationship between the change rate of the vegetation index obtained by the unmanned aerial vehicle multi-spectrum and the ground boll opening rate was established to realize rapid non-destructive testing of the boll opening rate. The normalized difference vegetation index (NDVI) and green normalized difference vegetation index (GNDVI) had good prediction ability for the boll opening rate. NDVI in the training set had an R2 of 0.912 and rRMSE of 15.387%, and the validation set performance had an R2 of 0.929 and rRMSE of 13.414%. GNDVI in the training set had an R2 of 0.901 and rRMSE of 16.318%, and the validation set performance had an R2 of 0.909 and rRMSE of 15.225%. The accuracies of the models based on GNDVI and NDVI were within the acceptable range. In terms of predictive models, random forests achieve the highest accuracy in predictions. Accurately predicting the cotton boll opening rate can support decision-making for harvest and harvest aid spray timing, as well as provide technical support for crop growth monitoring and precision agriculture.

The electro-thermal behaviors of the lithium-ion batteries corroded by the salt spray environment

Although the application of lithium-ion batteries in the marine environment such as electric ships and other energy storage equipment, has gradually flourished in recent years, the effect of the special salt spray environment on the cells has not been carefully revealed since it may pose a corrosive threat to the metallized cells. In this paper, the electrochemical performance, aging mechanism, and thermal behavior of the cells after subjecting to different salt spray times are investigated experimentally. The results show that the corrosion morphology of cells is increasingly serious with the salt spray time, destroying the internal structure of the battery and accelerating its aging. The capacity decay mechanism is mainly due to the loss of active material (LAM), while the contribution of the loss of available lithium inventory (LLI) gradually increases and tends to prevail upon the former as the corrosion time prolongs. Findings also show both a larger state of charge and longer salt spray time will result in a much higher battery temperature during the cycling process. The maximum temperature of LIBs with 100 % SOC and salt spray time of 40 h reaches 36.23 °C during the 50th cycle, while that for 0 % SOC is only 30.56 °C. Therefore, the corroded cells age faster, generates more heat, exhibits worse safety performance, and is more likely to cause thermal runaway and other safety issues than the normal ones.

Identification and Control Model for Pest Organisms in Cabbage Plants

The aim of the research is to identify pests according to family and find out the types and concentrations of vegetable pesticides that are effective for controlling pests on cabbage plants using vegetable pesticides, using net sweeping and using light on cabbage plants. This research activity included 2 stages. The first stage is to identify pests on cabbage plants using the insect net method and light lamps, taking insects directly every 7 days of observation. The number of pest insects obtained is recorded and identified based on their family. The second stage is the application of vegetable pesticides and the frequency of spraying on the intensity of pest and disease attacks on cabbage plants. This research is a factorial experimental study using a randomized block design (RAK) method consisting of 2 factors with the first factor being the type of vegetable pesticide consisting of 4 levels, namely (F0) control, (F1) neem, (F2) Annona and (F3) Widuri. The second factor is that the spraying frequency varies, consisting of 3 levels, namely (K1) 3x spraying (K2), 5x spraying and (K3) 7x spraying. Parameters observed included plant height, number of leaves, plant fresh weight, percentage of pest attack intensity and incidence of cabbage disease. Data were analyzed using the Duncan Multiple Range Test (DMRT) 5%. The research results show that the insect pests identified are the families Pyralidae, Plutelidae, Acrididae, Noctuidae and Aphididae. The results of testing a pesticide that is effective in controlling insects is neem pesticide with a spraying time of 7 times which can reduce the intensity of pest and disease attacks on cabbage plants

Productivity analysis of agricultural UAVs by field crop spraying

The article presents an analysis of the performance of agricultural UAVs when spraying field crops. Based on an analysis of the current state of technology for using UAVs in precision agriculture, a model for calculating UAV performance has been developed, based on the time structure of the crop spraying process, including the time of spraying, replenishment of mineral fertilizers or pesticides, and UAV flight. It is noted that for an agricultural UAV, when used in a precision farming system, the equation of existence must relate the take-off mass, the functional components of the take-off mass and the parameters of the sprayer, ensuring differentiated application of pesticides and fertilizers. Based on the proposed performance model of agricultural UAVs, recommendations are given for choosing the type of UAV for spraying crops. This model allows us to generalize methods for testing the production performance of agricultural UAVs, build models of production efficiency and provide proposals for technological solutions to improve these performance characteristics.

Improving spray performance of vehicle disinfection systems in livestock farms using computational fluid dynamics analysis

Effective vehicle disinfection systems (VDSs) are crucial in livestock-related industries to prevent the spread of diseases. This study aimed to improve the nozzle arrangement and operation of VDSs using computational fluid dynamics (CFD) simulations. The CFD simulations were conducted for two types of systems (simple and tunnel) which are commonly installed at farm entrances, and five vehicle types, including sedans, SUVs, cargo trucks, box trucks, and feed trucks. The results demonstrated significant improvements in the disinfection coverage and uniformity. For the simple-type VDS, the existing system exhibited low disinfection coverage on the wheels, top, and rear sections of vehicles; however, the modification of the nozzle positions and angles improved the coverage and uniformity. Additionally, increasing the number of nozzles and spray volume resulted in a 36–48 % increase in coverage across the vehicle entire surface. The tunnel-type VDS exhibited excessive disinfectant spray, leading to surface runoff and uneven coverage at the wheels and rear sections. This excessive disinfectant usage was reduced by 17 % by adjusting the nozzle arrangements and reducing spraying time by 5 s, while maintaining comparable coverage and uniformity. These findings highlight the importance of enhanced nozzle design and spray volume for effective vehicle disinfection. Livestock-related industries can enhance biosecurity measures and mitigate disease transmission risks by implementing the proposed improvements.

Investigation of oil mist filtration performance of surface modified coalescence filters with asymmetric wettability

Fibrous coalescence filters are widely used to remove oil mists from air and gas streams in industrial applications. The wettability of filter media significantly affects the filtration performance. Although some efforts have been made to improve the filtration performance based on the modification of filter media wettability by surface treatment method, of which the influence on liquid transport mechanism in the filters and the filtration performance is still needed to elucidate. In this paper, oleophilic filter media were treated by fluorocarbon copolymer solution using a spraying method. The effects of the treated area ratio, spraying time and combinations of patterned filter media on the filtration performance were investigated experimentally. The results show that the increase of the treated area ratio contributes to a variation on the wettability from oleophilic to oleophobic, resulting in a decrease in the jump pressure drop and an increase in the filtration efficiency. The treated filter medium under the optimal spraying time has the highest quality factor, which is 2 ∼ 3 times the untreated one. For the dual-layer patterned filters with alternative oleophobic and oleophilic strips, when the number of oleophobic strips patterned in the first layer filter medium is the same, the pressure drop and filtration efficiency of the overlapped arrangement are lower than those of the staggered arrangement. In all configurations, the highest quality factor is found in the dual-layer filter with the overlapped arrangement and four oleophobic strips patterned in the first layer, resulting from the lowest steady pressure drop and relatively high filtration efficiency.

Evaluating Corrosion Resistance of Metal Materials in Fire Productsvia Saltwater Spray Test Under Various Experimental Conditions

The brine concentration and salt spray time of KS D 9502, a saltwater spray test commonly used in Korea, were used to experimentally confirm the corrosion in iron, copper and stainless steel, and the degree of corrosion in fire extinguishers, automatic diffusion extinguishers, and residential automatic extinguishers. The results of the KS D 9502 brine spray test confirmed that there was little difference between iron and stainless under all test conditions, and that the results of the salt water test for copper were nearly identical to those of 5 wt% and 240 h (10 cycles). Unlike the two previous sets of conditions, the test results obtained at 5 wt% and 120 h of saltwater of the raw material showed very few visual (qualitative) and weight (quantitative) changes in corrosion, rendering these conditions unsuitable for the saltwater spray test. The saltwater spray tests in the fire extinguisher, automatic diffusion fire extinguisher, and residential automatic fire extinguisher showed that the results obtained at 5 wt% salt water and 240 h (10 cycles) and those obtained at 20 wt%, 240 h were nearly identical. These experimental studies show that the saltwater spray test of KS D 9502 is a variable in the corrosion resistance test, in which the time of the saltwater spray test is more important than the saltwater concentration.

A New Perspective to Understand the Late Season Abundance of Delia antiqua (Diptera: Anthomyiidae): A Modeling Approach for the Hot Summer Effect.

The onion maggot, Delia antiqua (Meigen), is one of the most important insect pests to agricultural crops within Allium genus, such as onions and garlic, worldwide. This study was conducted to understand the seasonal abundance of this pest, with special reference to the hot summer effect (HSE), which was incorporated into the model of summer diapause termination (SDT). We assumed that hot summer temperatures arrested the development of pupae during summer diapause. The estimated SDT curve showed that it occurred below a high-temperature limit of 22.1 °C and peaked at 16 °C. Accordingly, HSE resulted in delaying the late season fly abundance after summer, namely impacting the third generation. In Jinju, South Korea, the activity of D. antiqua was observed to cease for more than two months in the hot summer and this pattern was well described by model outputs. In the warmer Jeju Island region, Korea, the late season emergence was predicted to be greatly delayed, and D. antiqua did not exhibit a specific peak in the late season in the field. The abundance patterns observed in Korea were very different from those in countries such as the United States, Canada, and Germany. These regions are located at a much higher latitude (42° N to 53° N) than Korea (33° N to 35° N), and their HSE was less intense, showing overlapped or slightly separated second and third generation peaks. Consequently, our modeling approach for the summer diapause termination effectively explained the abundance patterns of D. antiqua in the late season. Also, the model will be useful for determining spray timing for emerging adults in late summer as onion and garlic are sown in the autumn in Korea.

An overview on spray pyrolysis deposition of metal oxide thin films

This work provided an overview on the synthesis of metal oxide thin films on different types of substrates (soda lime glass, fluorine-doped tin oxide glass, silica glass, stainless steel, quartz, silicon and microscopic glass slide) using spray pyrolysis method. The fundamentals, advantages and limitations of this method have been described. Experimental results indicated that the properties of films were strongly depending on the specific process parameters (nozzle type, distance between nozzle and substrate, solvent type, solution flow rate, precursor concentration, compressed air pressure, spray time and substrate temperature). It was noted that deposition temperature could control the surface chemical composition based on the experimental results. The presence of amorphous or polycrystalline structure could be observed for the films prepared at different deposition times as indicated in XRD studies. The obtained films indicated excellent absorption coefficient value (104 to 105 cm-1) and high transmittance value (more than 82 %) in the visible and infrared portion.

Effect of Thermal Spraying Method, Time and Temperature on the Thickness of Thermally Grown Oxide and Lifetime of Thermal Barrier Coatings

Effect of Thermal Spraying Method, Time and Temperature on the Thickness of Thermally Grown Oxide and Lifetime of Thermal Barrier Coatings

Optimizing Fungicide Sprays to Tackle Powdery Mildew (Uncinula necator) At The Right Time For healthy grapes production

Introduction: Powdery mildew, caused by the fungus Uncinula necator, is a prevalent and harmful disease affecting grapevines, resulting in decreased fruit set and yield. This study aimed to evaluate the effectiveness of various fungicides and spray timings in managing U. necator in grape vineyards. Methods: A field trial was conducted in Pishin, Balochistan in 2020, employing a randomized complete block design with two factors: four fungicides (control, protective fungicide-Bordeaux mixture, curative fungicide-Elite 45 wp, systemic fungicide-Quintec) and four spray timings (dormant spray, bud break, one week before bloom, and berry formation). Results: The findings revealed significant variations in disease severity (PDI) among leaves, inflorescence, and bunches across different fungicides, spray timings, and their interactions. Application of the protective fungicide one week before bloom proved highly effective in preventing U. necator infection, resulting in the lowest PDI values for leaves (0.44%), inflorescence (0.67%), and bunches (0.0%). Curative fungicides sprayed at bloom stage also reduced PDI for inflorescence (2.17%) and bunches (3.56%). Systemic fungicides applied during berry formation exhibited lower PDI for inflorescence (6.44%) and bunches (4.0%) compared to other fungicides. The highest grape production (27.10 t ha-1) was achieved with the protective fungicide sprayed at bloom stage, followed by the curative fungicide at bloom stage (25.87 t ha-1). The negative and highly significant relationship (R2=0.809) between PDI of leaves and grape yield indicated that higher disease severity led to decreased yield. Conclusion: In conclusion, a protective fungicide spray before bloom, followed by a systemic fungicide spray at berry formation, effectively controls U. necator and ensures healthier and higher grape yields.

Evaluation of the Effect of Preharvest Melatonin Spraying on Fruit Quality of 'Yuluxiang' Pear Based on Principal Component Analysis.

Melatonin (MT), an indoleamine compound, has a pleiotropic effect on plant growth and development and can regulate the quality of tree fruit. Systematic research on the effect of preharvest MT spraying on pear fruit quality and technical solutions for MT application to regulate pear fruit quality are still lacking. Thus, here we aimed to evaluate the effects of different spraying times, concentrations, and exogenous MT application times on 'Yuluxiang' pear fruit quality. Our results showed that the single fruit weight and vertical and horizontal diameters of pear fruit sprayed with MT twice at 30 and 90 d after full bloom were the largest, and the red and green values of the treatment were the highest. MT-treated pears had higher contents of total soluble solids, soluble sugar, sucrose, sorbitol, fructose, and glucose and lower contents of titratable acid, malic acid, and citric acid. Moreover, exogenous MT treatment increased the pear peel strength. Based on the principal component analysis of 10 fruit quality indices, the suitable periods for MT spraying on 'Yuluxiang' pears were 30 and 90 d after full bloom, the suitable concentration was 100 μmol/L, and the suitable number of times was two. This study provides a theoretical reference for optimizing MT application and improving pear fruit quality.

Exploiting asynchronous host-parasitoid emergence distributions to optimise insecticide applications and protect beneficial insects– a case study using the citrus gall wasp Bruchophagus fellis (Hymenoptera: Eurytomidae)

The citrus gall wasp (CGW), Bruchophagus fellis (Girault) (Hymenoptera: Eurytomidae), is a serious pest of citrus in southern Australia. Severe infestations can result in yield loss and a reduction in fruit size. Several parasitoid species attack CGW, with Megastigmus brevivalvus (Girault) (Hymenoptera: Torymidae) (MBV) being the dominant species. Both CGW and MBV are univoltine and adult wasps emerge from galls in the spring. Median emergence of MBV lags behind that of CGW by 2–3 weeks. We modelled the effect of spray timing for foliar-applied, non-systemic insecticides on the relative exposures of CGW and MBV based on their emergence distributions and estimated the optimal spray timing that maximises the control of CGW while minimising the impact on MBV. Three temporal emergence distribution scenarios for the two species and 28 periods of residual insecticide activity were considered in the investigation. The results showed that the optimal spray timing was always before the peak emergence of CGW. Depending on the residual activity of the insecticide, the optimal spray date pre-dated the peak emergence of CGW by 1–24 days, with longer lead times for insecticides with longer residual activity. By contrast, the optimal spray date varied little across the different emergence scenarios, suggesting that the results apply over a wide range of locations and seasons. A single insecticide application at the optimal timing may not guarantee satisfactory control of CGW. When the residual activity of the insecticide is short, multiple applications with a combined residual activity of 16 days are needed to ensure insecticide contact with ≥90% of all CGW that emerge in a season.

SO3/sulfuric acid mist removal in simulated flue gas: Multi-factor study based on two-film theory mass transfer process

SO3/sulfuric acid mist is a strongly irritating pollutant presented in small quantities in flue gas, which poses a major threat to the power plants operation and atmospheric environment. In this study, SO3/sulfuric acid mist at different positions and after different spraying time of the small desulfurization tower were extracted and absorbed by isopropanol solution, and the SO42- concentration was detected by barium-thorium titration. Then the SO3/sulfuric acid mist mass transfer model in desulfurization process was constructed on the basis of two-film theory to investigate the effects of different tower structures, spraying time and operating conditions on SO3/sulfuric acid mist removal in desulfurization tower. The results showed that the tower structures had the greatest influence on SO3/sulfuric acid mist removal, and the highest SO3/sulfuric acid mist removal efficiency was achieved after the spraying time of 0–20 min and at the flue gas distribution plate. Moreover, according to the results of SO3/sulfuric acid mist mass transfer model, SO3 removing process was not controlled by solid dissolution instead of by gas–liquid film turning to gas film with flue gas residence time running in the tower. The model results also showed that SO3 removing process was controlled by gas film for a very short period then turning to gas–liquid film immediately with spraying time accumulating in a specific tower position. Besides, it showed the increase of NH3 concentration and spraying flow rate promoted the SO3/sulfuric acid mist removal, and the increase of SO2 concentration and slurry temperature inhibited the SO3/sulfuric acid mist removal.

Mathematical Model of Propagation of an Aerosol Created by an Impulse Method in Space.

When developing neutralization systems for harmful agents, it is necessary to understand the mechanisms of the formation and evolution of an aerosol cloud in a closed or open space. Effective decontamination with aerosol clouds is provided by a rather high particle concentration and dispersion in an open space or on contaminated surfaces. This paper considers neutralization systems based on pulsed powder aerosol generators. It is shown that an aerosol cloud consisting of micron- and submicron-sized particles appears for several seconds after spraying. A further evolution of the aerosol cloud in a room is associated with the gravitational settling, diffusion, and coagulation of particles and their settling on the walls and ceiling. In the case of an open space or a ventilation system in a room, the evolution of the aerosol cloud is affected by the airflow. The main purpose of this paper is to determine the most important parameters and critical conditions of pulsed aerosol generation. A mathematical model is, thus, proposed for pulsed aerosol generation, and its parametric study is conducted in the most typical conditions. The purpose performance predicted by the model is the mass concentration of aerosol particles in the air and on surfaces, depending on the time of particle spraying and dispersion.

An autonomous task assignment and decision-making method for coverage path planning of multiple pesticide spraying UAVs

As the approaching of Agriculture 4.0 era and advancements of new technologies of Unmanned Aerial Vehicles (UAVs) and particularly quadcopter UAVs, plant protection quadcopters are becoming increasingly popular and practical in pesticide spraying, fertilization, pollination, seeding, and other agricultural activities. One of the main problems for plant protection quadcopters is completing planning tasks efficiently and quickly. Therefore, this paper proposes an autonomous task assignment and decision-making method for coverage path planning by multiple cooperative quadcopters. The Sequential Quadratic Programming (SQP) method is adopted to acquire the optimal solution for the proposed problem. Then, a simulation platform by MATLAB Graphical User Interfaces (GUIs) is established using the Stateflow technique, and multiple ZY-UAV-680 quadrotor UAVs are employed to carry out the actual flight tests. Finally, simulations and actual flight tests are conducted to demonstrate the effectiveness of the autonomous optimal task assignment and decision-making method. The final results show that: the proposed method can divide multiple UAVs reasonably to several blocks; the time differences between the simulation test and real flight test are only 39.8 sec and 20.6 sec, and accounts for 6.6% and 3.9% of the spraying time spent on real flight test by three cooperative quadrotors, respectively; the optimal scheme can save 60.8 sec and 80.0 sec in the simulation tests and the real flight tests, which accounts for 10.8% and 13.2% of the time spent on average scheme, respectively. Therefore, it can be concluded that the simulation results can match the real flight test results quite well regardless of average scheme or optimal scheme, and the optimal scheme is more efficient and timesaving than the average scheme.

Optimization of the Si3N4 coating formation through plasma spraying on Inconel 738

ABSTRACT In the present study, the deposition of silicon nitride (Si3N4) coating on Inconel 738 through plasma spray has been investigated. For producing the Si3N4 coating, different times (6, 8 and 10 s), different distances of the plasma spray torch from the substrate (30, 35 and 40 mm) and different currents for plasma spraying (3000, 3250 and 3500 A) were employed. For the characterisation of the coatings, SEM (thickness), XRD, micro-hardness and adhesion of the samples were measured. The coatings’ surface morphology was investigated through SEM. Based on the experimental results, by using a spraying time of 10 s, a distance of the torch of 40 mm and a current of 3500 A, high microhardness and adhesion of the coatings are obtained. On the other hand, the thickness of the coating increased by reducing the distance and increasing spray time and current.

Study on the Cooling Effect of Double-Layer Spray Greenhouse

Greenhouses provide suitable environmental conditions for plant growth. Double-layer plastic greenhouses are often used in many regions to ensure normal crop growth during winter since single-layer plastic greenhouses have poor insulation. However, during summer, the high insulation of double-layer plastic greenhouses, combined with excessive external solar radiation, can cause high temperatures inside the greenhouse that are not suitable for plant growth and require cooling. In this study, we propose a double-layer spray greenhouse using a high-pressure spraying system that is placed inside the double film that allows for additional cooling capacity during the summer in order to sustain plant growth. A greenhouse platform test was set up to investigate the optimum operating conditions for the nozzles and to explore changes in greenhouse microclimate under different nozzle operating conditions. The results show that (1) the cooling rate increases with increasing water supply pressure, nozzle diameter and spraying time, and the humidification rate is consistent with the change in the rate of cooling. (2) The optimal condition for cooling in this experiment is achieved with a 120° double nozzle with a nozzle diameter of 0.30 mm, a water supply pressure of 6 MPa, and a spraying time of 15 min, which can reduce the temperature by up to 5.36 °C and serve as a reference for the summer cooling of the double-layer greenhouse.

Experimental investigation of the characteristic of vacuum spray cooling for tofu

The present study proposes a rapid cooling method based on vacuum spray cooling, and establishes an experimental system to study the cooling performance of this method by taking tofu as an example. In this study, the effects of vacuum spray cooling, vacuum cooling and immersion vacuum cooling on the cooling rate, water holding rate, PH, TPA and other properties of tofu were compared. The total cooling time of vacuum spray cooling (13.86 min) was shorter than that of immersion vacuum cooling (33.39 min) but longer than that of vacuum cooling (10.64 min) for a temperature decrease from 70°C to 4°C. For weight loss from 70°C to 4°C, vacuum spray cooling (2.96%) was significantly less than that of vacuum cooling (10.21%). The PH value after cooling has no significant difference, but the color difference and water holding capacity of the sample after vacuum spray cooling are obviously better. However, the textural properties of the sample cooled by vacuum spray cooling were close to (for elasticity and viscosity) and better (for hardness and chewiness) than those of immersion vacuum cooling. In addition, compared with the two cooling methods in terms of storage, vacuum spray cooling can effectively maintain the moisture content, water holding rate, PH, chromatism and TPA of tofu, thus extending the fresh-keeping period of tofu. The conclusions of this paper provide theoretical support for prolonging the preservation period of food and optimizing the cooling process.