Dongguan canning factory of exhaust requirements:

After food canning before sealing, the tank top gap between air out as far as possible, make the seal after the tip clearance in canned form part of the vacuum process.General tank vacuum in 250 ~ 450 MMHG column.Exhaust is the purpose of: (1) to prevent the growth of aerobic bacteria and mold growth;(2) to prevent or mitigate sterilization by heating air to expand and make container deformation or damage, especially cause edge pressure is too large, which affects its sealing;(3) in control or reduce the canned food storage tank wall corrosion;(4) to avoid or reduce the change of food color, aroma, taste;(5) to avoid damage to vitamins and other nutrients;6. Help to avoid the use of false tank for corruption alterative bilge tank.Exhaust method usually has three kinds: (1) thermal exhaust method, using the principle of thermal expansion, air, steam and food will tank air out.Hot charging tank sealing and heated exhaust food canning two methods;(2) the method of vacuum sealing and exhaust, closing in vacuum environment;(3) steam injection can sealing method of exhaust, when closing to the canned headspace injection steam, will air out and seal.

Dongguan canning factory sealed requirements: Food produce deterioration is the most direct reason microbial breeding, so for the canned food, is the most important one, guarantee the number of microorganisms in the canned almost to zero (commonly known as commercial sterile).Second, canned seal completely won't cause again by microbial contamination.So in the process of canned food processing, the most important is two procedures: sealing, high temperature high pressure sterilization (like a pressure cooker at home cooking).

The sealing seal is canned food one of the key working procedure of long-term preservation.Within the seal is made after sterilization of canned food and isolated from the outside world, no longer by the outside air and microbial pollution caused by the corruption.When loss of canned container (or even a sudden) its sealing, cannot achieve the purpose of long-term preservation of food.Metal cans sealing work by the can sealing machine, the most common closing machine is semi-automatic, automatic and vacuum seamer (see food engineering).Glass bottles of seal depend on jar or tank cap form different modelling and reel type, rotary, or set of cover type sealing machine for sealing.Plastic composite materials (bag or cup) seal commonly used high frequency, hot pressing and pulse type seal method, sealing side, block. Dongguan canning factory sterilization requirements:

The food contaminated by pathogenic bacteria, bacteria killing toadstool, corruption, but allow residue in the tank is not under special circumstances cause tank food corruption microorganisms or spores exist, therefore also called "sterile business".Sterilization as well as the food must be enzymes to destruction, and as far as possible to save food quality and nutritional value.Can borrow heating sterilization, heated to above 100 ℃ sterilization said high pressure sterilization, the sterilization under 100 ℃ said atmospheric pressure sterilization or pasteurization.Sterilization process condition is mainly composed of temperature, time, back pressure, three main factors to control, to achieve different product needs sterilization intensity (F0) value.Usually, canned food according to the pH value can be divided into low acidity (pH > 4.5), the acid (pH3.7 ~ 4.5), high acidity (pH < 3.7) 3 class, they are by different microorganisms (see food microorganisms), the corresponding different sterilization intensity (F0) value.Low acid canned food sterilization require high strength, must use high pressure sterilization;And the acidity and high content of acid canned food sterilization intensity is lower, generally in atmospheric pressure sterilization.Every kind of canned food sterilization process conditions, in the past, most of them adopt empirical method to determine, is now a more scientific method to develop, namely on the one hand, determined the object of the corruption of the product of heat resistance (D) value (at a certain temperature the bacteria killed the time required to 90%), on the other hand, the determination of the various parameters in the process of pasteurization heat transfer characteristics of the product, and then through the formula to calculate the minimum bactericidal strength values.Sterilization operation is usually in a vertical or horizontal sterilization pot with direct steam or heat water.There are will be in front of the canned food sterilization before loading in the sterile environment sterile container and seal, this is called the aseptic canning or aseptic packaging.In addition, there is fire sterilization method (direct rolling on flame heating metal cans), hot air sterilization method;And according to the specific provisions of equipment form has rotary, vibrating, no basket (canned not installed basket directly into sterilization pot), water seal and hydrostatic pressure method (see food engineering).

Dongguan canning factory cooling requirements:

Canned sterilization immediately after cooling, in order to reduce the impact on the food quality.To prevent the cooling tank inside and outside differential pressure produced by the dramatic change of canned coign, burst or dented cans, should pay special attention to the correct control of back pressure tank.Cooling water typically chlorination, and keep the residual active chlorine 1 ~ 3 PPM, lest after sterilization tank is secondary pollution by cooling water