Fruit fruits and vegetables provide a large number of essential vitamins and other indispensable rare elements to the human body. The preservation and processing technology of fruits and vegetables is very important. With the rapid development of science and technology, various kinds of fresh-keeping processing technologies have been produced, but in the process of processing, unscrupulous businesses will add or use preservatives that are harmful to human health. In recent years, due to factors such as water pollution, air pollution, and reasons, the safety problems posed by the consumption of fruits, fruits and vegetables that have been seriously polluted by pesticides are increasingly attracting the attention of countries around the world. The safety of fresh-keeping processing of fruits and vegetables is very severe. 1. Current status of quality and safety of fruits and vegetables in China In order to ensure the safety of the “vegetable basketâ€, the Ministry of Agriculture in April 2001 proposed a “pollution-free food action planâ€. In April 2003, it launched a national certification for pollution-free agricultural products. Since August 2007, in order to restore the confidence of the international community in "Made in China," the State Council has launched nationwide special rectifications on product quality and food safety, and on the management of quality and safety of fruits and vegetables, it has carried out high-toxicity pesticide rehabilitation and agricultural product wholesale markets. The rectification action will focus on cracking down on illegal additions of banned pesticides such as methamidophos in fruits and vegetables, and will include all large and medium-sized cities’ agricultural product wholesale markets within the monitoring scope, focusing on checking the qualifications of certified agricultural products, conditions for production, and production. Process and product quality safety status. Strengthen the monitoring of production areas and the confirmation of the qualification of entering the market to sell certified products [5]. Therefore, according to the monitoring results of the Ministry of Agriculture in the first half of 2007, the average qualified rate of pesticide residues in fruits and vegetables was 93.6% [1], and the quality and safety of fruits and vegetables were generally satisfactory. However, with the detection range from major cities to the general farmers' markets in general cities, counties, and big cities to the general farmer's markets, with the detection of objects from the farmers' market to the production base, with the increase in pesticide detection content, fruit and vegetable detection varieties, batches , found that the problem of the safety of fruits and vegetables still exists. The main performances are as follows: high-toxic pesticides continue to be banned for many times, excessive levels of nitrates and heavy metals are common, black cabbage, poisonous leeks, fresh vegetables with dichlorvos, and Yongnian Garlic have happened from time to time, and export trade security disputes have increased. It is difficult for the safety and security of fruits and vegetables in small and medium cities in China[2]. 2. Risk analysis of fruits and vegetables 2.1 Large-scale cultivation and export of developing countries With the globalization of the economy, the demand for fruit and vegetable exports from developing countries, which are mainly planted, is increasing. For this reason, developing countries plant large quantities of fruits and vegetables to trade in export trade, promote economic growth, and have a large quantity, and quality is difficult to manage and monitor [3]. 2.2 Characterization Factors Unreasonable emissions of industrial “three wastes†and abuse of pesticides; pollution from production bases cannot be effectively controlled; inputs for fruits and vegetables include various agricultural production materials such as fertilizers, pesticides, and seeds. Except for the unscientific use of the means of production by farmers, the irrational structure of the input of fruits and vegetables and the unqualified product quality are another fundamental cause of the serious pollution of non-point sourced fruits and vegetables. In addition, the short growing period of fruits and vegetables, high requirements of fertilizer and water, high pest and disease, rapid development of diseases and insect pests, difficulty in control of production characteristics, and the requirement of high marketed fresh activity and short shelf life demand make food and vegetables safe for use in agricultural products. With large hidden dangers, the difficulty of security management control increases [4]. Severe pesticide residues in fruits and vegetables At present, China's fruit and vegetable production still takes the family as the unit, and the decision-making body of production management is farmers. Due to the restriction of producers' own knowledge, farmers generally lack scientific decision-making abilities, lack of safety awareness and legal system concepts, violations of pesticide management, food safety management, etc., and unscientific use of pesticides, chemical fertilizers, ripening agents, etc.[5]. The serious pollution of fruits and vegetables agricultural products; In addition, do not adhere to safety intervals, the market after spraying, endangering people's health, causing serious economic losses. For example, in 2002, the 300 tons of “Pink Lady†apple initially determined by Shaanxi Province and foreign companies had only 20 tons of supply of the pesticide standard, and the economic losses were heavy. A spot check result by the national quality inspection department in 2002 showed that there were 9 kinds of pesticide residues in 12 kinds of leek products exceeding the standard, and there were 10 kinds of pesticide residues in 16 kinds of cabbage products exceeding the standard. Among them, the highest level of acephamide content in the cabbage samples sampled was 15.8. Mg/kg, exceeding the national standard limit value of 79 times; Among the 181 kinds of vegetables sampled in 23 large and medium-sized cities, 86 kinds of vegetable pesticide residues exceed the national standard limit value, exceeding the standard rate of 47.5%. According to a survey conducted by the Ministry of Agriculture, about one-third of the country’s farmers use organic phosphorus high-toxicity pesticides in fruits and vegetables grown to varying degrees. Each year, more than 200,000 tons, more than 1,000 pesticides and even highly toxic drugs are applied to crops. Chemical pollutants can seriously damage people's health and damage the environment [6]. 2.3 Process Control Factors 2.3.1 Production process The main feature of China's current 80% fruit and vegetable production system is the adoption of small-scale decentralized management of farmers, coupled with the lack of empirical analysis on the quality of producers and the impetus for the application of quality and safety control techniques in the formulation of existing management policies. China's existing fruit and vegetable safety management measures have poor effectiveness and high costs. The pesticide residues found in fruit and vegetable products in China are mostly caused by the poor quality of the farmers' culture and drug errors [7]. 2.3.2 Processing Section Most of the production and processing enterprises of fruit and vegetable products in China are of small scale, and the production technology conditions and infrastructure are poor. The types of products produced and the quality of product hygiene are difficult to meet the needs of domestic and international markets. In the processing of fruits and vegetables for a long period of time, China only pays attention to pre-harvest cultivation and neglects post-harvest treatment. It does not achieve the commercialization of post-harvest commercialization of fruits and vegetables and cold chain circulation, and storage and transportation facilities are not perfect[8]. This not only leads to fruits and vegetables. The serious losses in the post-harvest distribution process also affect the safety of fruits and vegetables, causing problems in the transportation, storage and sale of fruits and vegetables. Problems such as poor production and handling during storage and transportation, improper disease control during storage, and lack of grade standards all affect the safety of fruits and vegetables [9]. In the fruit and vegetable preservation technology, chemical bactericide is the main treatment method to control the post-harvest diseases of fruits and vegetables. However, chemical bactericides are likely to cause residues of fruits and vegetables and cause environmental pollution; there is no standard for radiation quality of irradiated products. There are a series of problems such as non-monitoring doses and whether radiation can cause toxicity, carcinogenesis, teratogenicity and mutagenesis, etc. The safety of fruits and vegetables remains to be further studied [10]. 2.4 Institutional factors 2.4.1 Inadequate coordination of management system and lack of participation of the masses China's current agricultural product (food) safety management implements the "sub-regulation-based, supplemented by variety supervision" system [11]. However, on the whole, our government has insufficient pre-sales behavior inspections in the establishment of fruit and vegetable safety management systems. There are too many regulatory departments after the fruits and vegetables enter the market, and the safety management in transportation has become a vacuum zone. The quality and safety management of fruits and vegetables has reached “from farmland to There is still some distance in the management of the whole table [12]. The role of consumers in our country has not been fully realized. In addition, the current market access system for fruits and vegetables in our country is not perfect, and market certification, competition management and other vacancies have made it impossible for China's fruit and vegetable safety management to establish a mechanism for high quality and high prices for safe fruits and vegetables[13]. This has led to the inability of existing vegetable and vegetable management policies to mobilize farmers. The enthusiasm for safe fruit and vegetable production and the promotion of vegetable farmers' awareness of self-inspection of safety products. 2.4.2 Insufficiency of Mandatory Forces and Standard System of Laws and Regulations At present, the management of quality and safety of fruits and vegetables in China is mainly based on the "Agricultural Product Quality Safety Law"[14] and its supporting regulations that began in November 2006. However, this law is applied to certain subjects, certain links, or certain products of agricultural product production and management. Regulations, taking production records as an example, still do not clearly define the information requirements for each link of the supply chain, the main body of the issue of product traceability, and the responsibility of the supervisory authority. The labeling system problems mainly focus on three aspects: First, the standards are lagging, crossover, and repetition, and individual ones are even contradictory. Second, the degree of international matching is not high, the international adoption rate is not high, and some standards are inconsistent with international standards[ 15]; Third, there is no standard system for the system. At present, the quality and safety standards for fruits and vegetables in China lack production regulations, production environments, and testing method standards [16]. 2.4.3 weak technical and economic support The emphasis of China's agricultural science and technology public relations has just begun to shift to the quality and safety of fruits and vegetables. Corresponding to this, the fruit and vegetable production technology and corresponding detection technologies are required to be constantly updated. However, in reality, fruit and vegetable production technology can hardly meet the requirements of the development of safe fruits and vegetables industry. In short, there is a lack of scientific and technological support for the entire operation system of fruit and vegetable production in China. 2.4.4 lack of background information for risk assessment Currently, China lacks systematic monitoring and evaluation data on food-borne hazards. The pollution status of pesticide residues and biological toxins in fruits and vegetables is still lack of systematic monitoring data. The pollution status and health effects of some pollutants that are highly health-harmful and very sensitive to trade are still unclear. There is still a lack of fixed-point active monitoring networks. . Internationally, as far as chemical pollution is concerned, the World Health Organization and other organizations started the "Global Environmental Monitoring Plan / Food Pollution and Monitoring Project" as early as the 1970s. Some developed countries have established fixed monitoring networks and relatively complete pollutant and food monitoring data. 3. Fruit and vegetable preservation technology 3.1 Simple storage and preservation Simple storage consists of three basic forms of storage, burial (buried) and cellaring, and the resulting prosthetic storage and storage. These are the use of natural low temperatures to maintain the required storage temperature, simple equipment, easy operation, and have a certain degree of spontaneous preservation. Trench: Dig a trench deep into the earth from the ground, and its size and depth are mainly based on the local terrain, climatic conditions, types and reserves of fruits and vegetables. For example, in the case of apple ditch, the storage site should be chosen where the terrain is flat, the leewards are sunny, the soil is solid, dry and free of water, and the transportation and management are convenient. The size of the storage site can be determined according to the amount of stored fruit. The ditch is best from north to south. The depth of the ditch is generally 0.5-0.8 meters, and the ditch is 1-1.2 meters wide. The ditch length is determined by the topography and the amount of fruit. Each square meter of trench can store 250-300 kilograms of apples. Before entering the ditch, a layer of 5-6 cm thick clean sand shall be laid on the bottom of the ditch, and a plastic sheet shall be laid on top of the fine sand. Then, starting from one end of the ditch, the fruit is laid one after the other and the fruit thickness is 60-80 cm. After entering the ditch, cover the top of the fruit pile with a layer of plastic cloth and 2-3 layers of cold-proof paper, shade and snow, and keep it warm and cold. When the temperature is below zero degrees Celsius, a layer of leaves or straw is placed on top of the cold-resistant paper for insulation [17]. Stacking: An easy method of stacking fruit and vegetable products into piles. Stacking is easy to use, low in cost, and the covering can be adapted to local conditions and locally sourced. However, because the heap is directly deposited on the ground, it is affected by the outside climate, it is easy to fall in autumn, and it is difficult to keep the temperature in winter. Therefore, the effect of storage depends largely on the management of the cover after the accumulation, ie, according to the climate. Changes in time to adjust the coverage of time, thickness and so on. This storage method is generally used for pre-cooling or short-term storage before storage. Cellaring: Similar to a ditch, it is stored in underground cellars. Cellar is a kind of storage method that has evolved and developed on the basis of the ditch. It has a variety of forms, such as a cellar pit, a pit pit, a kiln pit, and a ventilating pit. Compared with burial, it is equipped with a certain amount of ventilation and heat preservation facilities, which can not only regulate and control the temperature, humidity, and gas composition in the pit, but also allow managers to freely check in and out of the product. Prosthetic storage: It is characterized by root harvesting, single plant or clustered planting. Storage conditions The appropriate temperature for storage is 0 to 1°C. Below 0°C, the bulbs are susceptible to freezing. Storage of the bulbs at high temperatures tends to cause wilting and rot. Suitable relative humidity for storage is from 90% to 95%. In areas that are not too cold in winter, the whole plant is harvested without roots, and the bulbs are bundled with the plant's leaves, and they are planted in facilities such as Yangshuo, storage ditch, and cellar pit before and after the winter season. A plant can also be arranged closely. Immediately after the implant, water it and then fill it as needed. As the weather changes, it is appropriate to cover and prevent cold, thicken the cover in the coldest season, prevent freezing, and release the air at a proper time. During the storage period, the nutrients of the plants are continuously transferred to the flower bulbs to allow them to continue growing. If the prosthetic storage of the curd is small, the temperature of the place can be controlled higher to speed up the expansion of the flower bulb, and the fully grown flower ball is not suitable for the prosthetic storage and is prone to the phenomenon of scattered flowers. Frozen storage: In the winter when frozen, the harvested fruits and vegetables are placed in the shallow ditch at the shade of the shade, covered slightly, and the natural low temperature is used to quickly freeze the fruits and vegetables after entering the ditch[18]. The structure of frozen storage is often narrow gutters, about 0.3m. If a wide gutter (1m or more) is required, ventilating channels must be provided at the bottom of the gully; shaders are generally to be installed to avoid direct sunlight, so as to accelerate the freezing speed of fruits and vegetables after entering the gutters. . The difference between frozen reservoirs and ordinary reservoirs is the shallowness of the frozen trenches and the thin coating. 3.2 Ventilation store storage preservation Ventilation storage is a storage form that controls the storage temperature by ventilation and ventilation using natural low temperatures. The entire building is a brick, wood, cement structure, ventilation system is set up, can make full use of hot and cold air convection heat exchange inside and outside the library, the warehouse has a thermal insulation structure, the insulation effect is also very good [18]. Ventilation storages are mostly rectangular or long strips. In order to facilitate management, the storage capacity should not be too large. At present, the ventilation storages in various parts of China are usually spanning from 5 to 12 meters in length and 30 to 50 meters in length. The height in storage is generally 3.5 to 4.5 meters. . The top of the library has arched tops, flat tops, and ridged tops. If you want to build a large-scale storage library, you can build several libraries to form a library group. In northern cold regions, most of the warehouses are divided into two rows with a central corridor in the middle, with a width of 6 to 8 meters. The direction of the warehouse is vertical to the corridor. The door opens to the hallway. There are louvers on the roof of the corridor and double doors at both ends to reduce the impact of cold winds in winter on the library. The library group in the warm area is better equipped with a single library door so as to use the ventilation of the library door. For example, the ventilation of the potato storage: (1) storage characteristics The edible part of the potato is underground tubers, generally have 2 to 4 months of physiological dormancy after harvest, the length varies from species to species. 2) Storage conditions The suitable storage temperature for fresh potatoes is 3 to 5°C, but potatoes used as potato chips or French fries should be stored at 10 to 13°C. The relative humidity of the stored air is 80% to 85%. If the humidity is too high, the rot may increase, and if the humidity is too low, the water may shrink and shrink. At the same time, it should be stored away from light, because the light will promote potato sprouting and increase the content of solanine glycosides. (3) Ventilation storage methods: Pay attention to the height of the storage stack when it is not more than 1 to 1.5m. Set the ventilation tube inside the stack, and leave some space around the stack for ventilation and heat dissipation. 3.3 refrigerated storage preservation Mechanical refrigeration is a modern way of storing fruits and vegetables. It is not limited by regional climatic conditions. According to the requirements of different types of fruits and vegetables, the temperature and humidity in the store can be controlled by the function of the mechanical cooling system to extend the storage life of the product. In seasons and regions where climate is high, manual cooling measures must be taken to manually refrigerate [18]. There are two ways: one is the more primitive ice; the other is modern mechanical refrigeration [18]. 3.4 atmosphere storage preservation Atmosphere storage is a kind of storage method that puts fruits and vegetables in a special sealed warehouse on the basis of refrigerating, and at the same time changes the gas composition of the storage environment. In the storage of fruits and vegetables, lowering the temperature, reducing the oxygen content, and increasing the concentration of carbon dioxide can significantly reduce the respiratory intensity and self-consumption of fruits and vegetables, inhibit the production of ripening hormone ethylene, reduce the occurrence of diseases, delay the aging process of fruits and vegetables, so as to achieve long-term storage and preservation. The purpose of [18]. 3.5 Other storage preservation Storage under reduced pressure: The fruit is stored in a pressure-bearing store, evacuated with a vacuum pump, and maintained at 0.02 to 0.05 MPa at a temperature of 15 to 24 degrees Celsius. The air passes through the storage tank to remove the volatile substances released from the product's storage.[18] ]. Radiation treatment: Using the principle of 60Co γ-rays with strong penetrating ability, the fruits and vegetables are irradiated and stored. Electromagnetic treatment: There are three methods: magnetic field treatment, high-voltage power plant treatment [19], negative ion and ozone treatment. Fresh-keeping coating: A layer of polymer liquid film is coated on the surface of the fruit and dried to form a very thin and uniform film, which can inhibit the gas exchange between the fruit and the air, and play the role of single fruit atmosphere regulation, thus inhibiting the breathing. Reduce the consumption of nutrients, delay ripening and aging; In addition, it can reduce evaporation and loss of fruit, maintain the hardness and freshness of fruits, and can reduce the rot caused by the infection of pathogenic bacteria. In addition, smearing preserves the brightness of the fruit and improves its appearance [19]. 4 Conclusion The safety of fruits and vegetables is not only very important for people's health, but also very important for the environment and economy. There are many domestic researches on the preservation technology of fruits and vegetables. In addition to the above-mentioned preservation techniques, there are ultraviolet rays, calcium treatment, fumigation and high-pressure preservation, and the research direction has gradually been towards materials science, food chemistry, organic chemistry, genetic biology, and mechanical engineering. In many fields such as learning, we must also strengthen institutional management and supervision. In order to improve fresh-keeping effect, prolong the freshness of preservatives, reduce costs, increase comprehensive benefits, and preserve fresh fruits and vegetables from a single technology to composite technology, various preserving technologies have become popular. Let everyone eat safe fresh vegetables and fruits. references: [1]VirgÃnia C. Fernandes, Valentina F. Domingues, Nuno Mateus: Determination of Pesticides in Fruit and Fruit Juices by Chromatographic Methods. An Overview [2]Rami Akkad: Determination of Organophosphorus and Carbamate Insecticides in Food Samples by High-Performance Thin- Layer Chromatography Multi-Enzyme Inhibition Assay [3]V. Domingues: Improving the safety and Quality of Fresh Fruit and Vegetables [4]GU.S. Department of Health and Human Services Food and Drug Administration Center for Food Safety and Applied Nutrition (CFSAN) October, 1998:Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables [5] Improving the Safety and Quality of Fresh Fruits and Vegetables: A Training Manual for Trainers [M].2010 University of Maryland [6]Ashley Predmore and Jianrong Li:Enhanced Removal of a Human Norovirus Sanitizers by a Combination of Surfactants and Surrogate from Fresh Vegetables and Fruits [J].Published Ahead of Print 27 May 2011 [7] AJian Wang, Willis Chow, Daniel Leung, and James Chang: Application of Ultrahigh-Performance Liquid Chromatography and Electrospray Ionization Quadrupole Orbitrap High-Resolution Mass Spectrometry for Determination of 166 Pesticides in Fruits and Vegetables [8]James H.Moy, Lyle Wong: IRRADIATION AS A QUARNTINE TREATMENT OF TROPICAL FRUITS [9]Lfe Fitz James, Bas Kuipers:Preservation of fruit and vegetables[M].Bas Kuipers [10]Steven Cummins, Dianna M Smith, Mathew Taylor, John Dawson, David Marshall, Leigh Sparks, and Annie S Anderson: Variations in fresh fruit and vegetable quality by store type, urban-rural setting and neighbourhood deprivation in Scotland [J] .Submitted 27 August 2008: Accepted 18 December 2008 [11] Gemma Oms-Oliua, Ma Alejandra Rojas-Graua, Laura Alandes Gonzalezb, Paula Varelac, Robert Soliva-Fortunya, Ma Isabel Hernando Hernandob, Isabel Perez Munuerab, Susana Fiszmanc, Olga Martin-Bellosoa: Recent approaches using chemical treatments to preserve Quality of fresh-cut fruit: A review [M].16 July 2009 [12]Raffaella Di Cagno, Rossana Coda, Maria De Angelis, Marco Gobbetti:Exploitation of vegetables and fruits through lactic acid fermentation [M].2012 Elsevier Ltd. 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All rights reserved:The Change Life Convenience Store Programme toIncrease Retail Access to Fresh Fruit and Vegetables: A Mixed Methods Process Evaluation [J ].June 2012 | Volume 7 | Issue 6 | e39431 [14]Joshua Matthew Merrill: Managing Risk in Premium Fruit and Vegetable Supply Chains [15]Mitch Ricketts, Coordinator, Health, Safety and Environmental Quality, K-State Research and Extension Kristy Wieland, Information specialist Instructor: Guide For the Fruit and Vegetable Preserving and Specialty Foods Manufacturing Industry [16]Meeta Punjabi Vijay Sardana: Initiatives and Issues in Fresh Fruit and Vegetable Supply Chains in India [J].New Delhi March 11 - 15, 2007 [17] Myriam Vander Stichele, Sanne van der Wal & Joris Oldenziel: Who reaps the fruit? [J]. une 2006 [18] R. Vidhya, A. Narain: Development of Preserved Products Using Under Exploited Fruit, Wood Apple (Limonia acidissma) [19]Lei Ji, Jie Pang, Sha Li, Bo Xiong and Liang-Gen Cai: Application of new physical storage technology in fruit and vegetable industry [J]. Accepted 2 December, 2011 [20]Shida Rastegari Henneberry, Kullapapruk Piewthongngam, and Han Qiang:Consumer Food Safety Concerns and Fresh Produce Consumption[J].Journal of Agricultural and Resource Economics 24(1):98-113 [21] Zhu Hongli, Yang Binbin, Zhang Xiuqi, Tang Weixia: "Preliminary analysis and development of fruit and vegetable preservation processing" Fresh Cut Sliced Tricholoma Matsutake Fresh Cut Sliced Tricholoma Matsutake,Sliced Tricholoma Matsutake,Fresh Cut Tricholoma Matsutake,Frozen Tricholoma Matsutake Guangyun Agricultural Biotechnology (Jiangsu) Co., Ltd , https://www.7-mushrooms.com