Basic concept I of the hottest low temperature log

The basic concept of low-temperature logistics (I)

the so-called low-temperature logistics generally refers to the storage and distribution of refrigerated and frozen foods. Enterprises providing low-temperature logistics are required not to change the product storage temperature conditions originally set by the manufacturer in any link. At present, the logistics charging standards are not uniform. Generally speaking, the charging for normal temperature distribution is about 4% - 8% of the purchase price of goods, while the charging for freezing or refrigeration is higher, about 2.5 times that of normal temperature

(1) frozen and refrigerated food because of the definition of food in some previous studies on human health problems

low temperature food can be divided into two categories according to temperature, namely, refrigerated and frozen. At present, freezing is the main method in practical work. Freezing requires four conditions: pretreatment; Rapid freezing; － Temperature below 18 ℃; Properly and completely packed

according to different raw materials, freezing can be divided into frozen aquatic products, frozen vegetables and fruits, frozen prepared food and others

the temperature of frozen food distribution center should be kept below - 18 ℃, and more than 93% of the food contained should be frozen into water, so as to prevent the quality change of food due to time, so it does not need to rely on any preservatives

in a broad sense, refrigerated food is generally defined as fresh aquatic products, animal meat processed products (sausage, ham, etc.), dairy products (butter, cheese, yogurt, etc.), aquatic processed products (fish sauce), agricultural processed products, gel foods (jelly pudding, etc.) within the temperature zone from below 7 degrees to above the freezing point

the two low-temperature forms of freezing and refrigeration are the best choice to maintain the basic characteristics of fresh, delicious and safe food. Therefore, in the real-time transportation of frozen and refrigerated food, vehicles with freezers or insulation devices should be used. When the shelf life of refrigerated food is within 14 days, and preservatives cannot be added, the implementation of hygiene and quality temperature management in the production and marketing stage has become the primary work of the cryogenic system

(2) classification of low temperature warehouse

low temperature warehouse is a link in the cold chain system after the sudden drop of product temperature at the initial stage. It is also the stronghold for low temperature products to stay in the cold chain system for the longest time. Therefore, the requirements for product quality play an important role in low temperature logistics management

low temperature warehouses are roughly divided into two categories: cold storage and freezing: cold storage warehouses mainly store vegetables and fruits, fresh fish meat, fish eggs, eggs, fresh milk, fruit juice, etc; Frozen warehouses mainly store meat, ice cream, etc

low temperature warehouses are divided into refrigerators, freezers and special refrigerators according to different warehouse temperatures

1) refrigerated warehouses: those whose storage temperature is maintained above the freezing temperature of products belong to refrigerated warehouses. Generally, the freezing point of fresh food is mostly - playing the role of incremental filling of more than 2 degrees. Due to the different properties of various products, the storage temperature also varies, and most of the storage temperature is below 4 degrees

2) freezer: all products whose temperature is maintained below the freezing temperature belong to the frozen warehouse. For example, the storage temperature of frozen fish or meat, frozen food, etc. stored for a long time is about to confirm the technical state and accuracy of the experimental machine below -23 degrees according to the difference of the comparison value

3) special refrigerators: those that need to control the temperature and humidity in the warehouse at the same time belong to special refrigerators, such as the refrigeration of fresh fruits and vegetables

Table 3-1 classification of low temperature warehouses

Project

level maintain temperature

(Celsius) humidity%rh

and other products

freezer f (SA) - above 20 - frozen fish meat, frozen food, ice cream

C1 (a) - 10 ~ - 20 - salted fish roe, ice cream (short term)

cold storage C3 (c) - above 2

10 - fresh milk, fresh fish meat (short-term), dried fish roe, fresh

fish roe, condensed milk, tea, cake, wine

special cold storage C3 (3) grade 0 ~ 5

10 ~ 15 80 ~ 95

70 fresh fruits and vegetables

ca 5 ~ 8 95 ~ 100

o2 3%

CO2 5%

fruits and vegetables, etc