Talk about the difference between traditional hot filling and aseptic cold filling technology
PET aseptic cold filling technology itself has not developed for a long time, but there are already several well-known beverage equipment manufacturers in the world with relatively mature aseptic cold filling technology. Compared with the traditional hot filling process. The traditional hot filling can be divided into two types, one is high temperature hot filling, and the other is to pasteurize the product after heating to 65 ° C ~ 75 ° C after medium temperature filling. In either case, the product, bottle and lid need not be sterilized separately, and the bottle and lid can be sterilized by holding the product at a high temperature for a sufficient period of time. Aseptic cold filling first needs to sterilize products, bottles and lids separately, creating an excellent environment for aseptic filling, filling in a sterile environment, and leaving the sterile environment after sealing. It is the finished product.
If only from the comparison of the two processes, the biggest difference is that the beverages have different heating times. It is well known that the longer the heat treatment time, the greater the effect on the quality and mouthfeel of the beverage. Aseptic cold filling uses UHT ultra-high temperature instantaneous sterilization, the heat treatment time of the material is not more than 30 seconds, and the sterilization effect can be ensured at high temperature, and the sterilization method of hot filling makes the material be in high temperature for a long time. Under, seriously affect the product taste, color and heat-sensitive nutrients (such as vitamins).
If we look at the configuration of the production line, when the filling machine has a faulty shutdown elbow, the material processed by the hot filling method has a partial reflow which will prolong the heating time, which will seriously affect the quality of the whole batch of products, and the aseptic cold filling This phenomenon does not occur, the material has been reduced to room temperature after instant sterilization, and it will not affect its quality in the aseptic tank.
Let's look back at the comparison of PET bottles. It can be seen from the filling process that the requirements of the two types of filling methods for PET bottles are different. Hot filling requires that the PET bottle can withstand the high temperature of 85 ° C ~ 92 ° C and maintain good heat resistance, which requires increasing the crystallinity of the PET material, while limiting the generation of induced stress during blowing. The PET bottle used has the following characteristics: the wall thickness of the bottle, the clear wall ribs to prevent heat shrinkage, and the need for a crystal bottle mouth, which greatly limits the freedom of design of the bottle type. Aseptic cold filling can use lightweight bottles (up to 60 ° C to 70 ° C), and its standard cover design, which greatly reduces the cost of the bottle and lid, and can also choose the bottle type freely. .
In the hot filling process, the beverage is kept at a high temperature for a long time, and bacteria and microorganisms are killed, and a preservative is added, so that the beverage safety is certainly high. How does aseptic cold filling ensure the safety of beverages? The fundamental, the most important thing is the establishment and protection of aseptic environment. Compared with hot filling, aseptic cold filling uses UHT ultra-high temperature instantaneous sterilization for material sterilization. The material has short heating time, little loss of nutrients, and no significant change in quality and taste. According to the latest foreign technology, the aseptic cold filling process can be combined with pasteurization for cold chain production, so that the loss caused by the nutrient content of the material is lower, and under the condition of cold chain, the safety of the product can be fully guaranteed. .
Sterilization improvement of packaging materials is the most critical step in the aseptic cold filling production process. Due to the heat resistance of the PET material design, it can only be sterilized by chemical reagents. To ensure that the bottles and lids are effectively sterilized, and the chemical reagents are not affected, the aseptic filling technology generally adopts the following Measures: The original number of colonies of the bottle originally required to be blown is not more than 5cf/bottle; the delivery bottle is made of sterile air, and there is an air conveyor belt; the inside of the bottle is sterilized by peracetic acid disinfectant (PAA), which can achieve high sterilization. Effect (up to 7log); disinfection of the outside of the bottle at the same time; disinfectant has automatic recovery and concentration measurement system to ensure stable concentration of disinfectant; rinse the residual disinfectant in the bottle with sterile water, then use sterile The air is blown dry to ensure that the residual disinfectant does not affect the material; the bottle cap is generally sterilized by immersion or spray sterilization, and the sterilization effect can be well ensured by controlling the soaking time and the spraying time. Since the PET bottle does not shrink after cold filling, there will be a part of the air between the material and the cap, and the oxygen therein will slowly oxidize during the storage process, thereby causing the beverage to deteriorate. Therefore, the aseptic cold filling equipment will add a nitrogen (or other inert gas) replacement system to blow off the air at the top to ensure that the material is not oxidized.
The aseptic cold-filled main equipment also emphasizes the hygienic design, which is mainly in the aspects of pipe and valve technology, planing of materials surface, surface design of important areas, selection of anti-corrosion materials, etc. Fully automatic cleaning (CIP) system, sterilization (SIP) system and equipment external foam cleaning system (COP). In addition, aseptic cold filling machines are designed with their own unique filling valves, all of which ensure that the equipment will not be given Secondary pollution of materials. For the maintenance of aseptic space environment, the cleaning room isolation measures are generally adopted. The main body filling machine is designed as a Class 100 air purification room, and there is a 10,000-level purification room outside (some aseptic filling equipment is not required). The filtration system in the purification room ensures the cleanliness of the air in the filling environment, so that the material will not be Secondary contamination by microorganisms suspended in the air. The neutral beverage cannot be produced by the hot filling process, mainly because it uses the inverted bottle method to sterilize the bottle cap. The hot filling of the high acid beverage can also inhibit the growth of microorganisms, while the neutral beverage can not guarantee the safety of the product. The product defect rate is very high. So the technology is very immature, and if a neutral tea beverage is produced by a hot filling process, a preservative must be added. For aseptic cold filling, the process adaptation will be gradually strengthened due to the filling under aseptic conditions, and the types of products that can be produced are very wide, including neutral tea drinks, milk drinks and other various beverages. The device can be adjusted to change the product type.
Among the factors affecting the quality of aseptic cold filling, the operator factor is a large part, because the operator is the largest source of pollution in the entire environmental system, and the air purifying room is also well cleaned while purifying the air. The pollution brought by the personnel is reduced; the operator has to undergo spray sterilization when entering the 10,000-level purification room; the design of the 100-level purification room is small and practical, so that the operator can operate without destroying the aseptic environment; The inner surface can be automatically cleaned and disinfected.
In terms of management, the aseptic cold canning technology of beverages is very high, and it is necessary to have a high level of technical personnel and high-quality management personnel for unified management. Generally, the HACCP management system is applied. All management must form a document system, and there are special personnel responsible for implementation. Only by standardizing management and clear process methods can we ensure the safety of aseptic cold-filled beverages.
Introduced the above content, and finally we look at the comparison of the cost of raw materials and production lines in the two production technologies. The input cost of the two filling methods is very different. The equipment for aseptic cold filling is in the same production capacity. The investment is much higher than the cold filling and blowing. However, the aseptic cold filling process is complicated, and there are many auxiliary equipments required around the filling equipment. In the overall comparison, the initial investment in an aseptic filling line is much higher than in the hot filling line.
In terms of raw material cost, the quality of the two types of bottles is very different. By reducing the weight of raw materials to reduce costs, the weight of the two types of caps is different due to the special requirements of hot-filled PET bottles. In terms of operating cost, aseptic cold filling has a sterilizing liquid consumption cost, but the total cost is still much lower than that of hot filling, and the faster the production line speed, the higher the output, and the lower the production cost. By comparison, it can be seen that the initial investment in aseptic cold filling is relatively large, but because the raw material cost and operating cost of aseptic cold filling are relatively low, the investment of the higher part will be recovered quickly. As the equipment is used for a longer period of time, the low-cost advantages of aseptic cold filling can be clearly demonstrated.
Traditional beverage hot filling technology and aseptic cold filling technology have been actively adopted. The technology has its own advantages. The traditional hot filling process is mature, the product risk is small, the operation is relatively simple, and the skill requirements for employees are not very high. However, its shortcomings in beverage preservation cannot be completely solved. The aseptic cold filling technology has complex process requirements and the product has certain risks. However, its products have the advantages that the hot filling can't match in the nutrition and preservation of beverages, and have a very broad prospect in the future market development. It should be noted that as modern filling technology becomes more sophisticated, aseptic cold filling will gradually replace hot filling as the most important means of beverage packaging.