Sterilization and application of beverage bottle caps?
?After the reform and opening up, China's beverage industry has developed very rapidly, and the types of beverages have gradually developed from simple carbonated drinks in the past to mineral water. , fruit juice, fruit and vegetable juice drinks and functional drinks, etc.; the filling method has also developed from cold filling to the current hot filling, medium temperature filling, aseptic cold filling, etc.; the packaging form has also evolved from a single glass bottle to the current Cans, PET bottles, etc. For different products and different packaging forms, the sterilization of packaging bottle caps is also critical. This article discusses the various sterilization methods of beverage bottle caps currently used. ?
1. Ultraviolet sterilization?
After microorganisms are irradiated by ultraviolet light, their proteins and nucleic acids absorb ultraviolet spectrum energy, which will cause protein denaturation and cause the death of microorganisms. ?
In beverage filling production equipment, the cap conveyor is a capping machine or capping machine that conveys bottle caps. Install ultraviolet sterilization lamps on the upper part of the storage bin of the cap conveyor or the upper part of the conveyor belt. The bottle caps are exposed to ultraviolet rays during transportation. A better sterilization effect can be achieved where the ultraviolet rays are irradiated. Due to the poor light transmittance of the bottle cap, ultraviolet rays cannot penetrate the bottle cap and irradiate to the other side of the bottle cap. Therefore, the bottle cap can only achieve partial sterilization, and the sterilized surface is random. In order to sterilize the surface of bottle caps in a targeted manner, an ultraviolet sterilizing lamp is installed on the cap slide of the capping machine or capping machine. The bottle caps passing through here have been arranged in the same direction. The side irradiated by ultraviolet rays is where the caps and caps are aligned. The side that comes into contact with beverages effectively improves the sterilization effect. ?
Ultraviolet sterilization equipment is simple, does not require supporting equipment, is low in cost, easy to operate and manage, and is widely used. Due to the structural characteristics of the slide and the killing properties of ultraviolet rays on microorganisms, ultraviolet sterilization methods are generally suitable for use in the following types of beverage filling bottle caps:?
1. Carbonated beverages Carbonated beverages contain CO2, which is acidic and can inhibit the growth of microorganisms. Therefore, ultraviolet sterilization of carbonated beverage bottle caps can meet the demand. During production of this method, new bottle caps packaged in batches are poured into the storage bin of the cap conveyor, and the caps are sterilized by ultraviolet radiation in the storage bin of the cap conveyor or on the conveyor belt; they can also be sterilized under the capping machine An ultraviolet sterilization lamp is installed on the cap slide to allow the inner surface of the bottle cap to be sterilized by ultraviolet rays. After sterilization, it is directly sent to the capping machine. ?
2. Mineral water beverages The state has formulated relatively strict regulations on the production of mineral water, in which the total bacterial count, mold count and E. coli in mineral water are strictly limited to zero. Regardless of whether mineral water has been filtered and sterilized, its total bacterial count, mold count and E. coli count must comply with national standards. Since mineral water only contains inorganic salts and does not contain microbial nutrients and lacks nutrients for microbial production and development, ultraviolet sterilization can also be used for bottle caps. ?
3. Tea drinks and fruit juice drinks filled at high temperature? Various microorganisms (bacteria, molds, yeasts, etc.) exist in tea drinks and fruit juice drinks. The sterilization of beverages is to kill these microorganisms. At present, high-temperature short-term sterilization method is generally used, also known as instant sterilization method. High-temperature filling is to cool the beverage after instant sterilization to a temperature range between 85°C and 92°C for filling. The beverage bottle uses a crystalline heat-resistant hot filling bottle, and the bottle cap uses a heat-resistant bottle that can withstand 85°C. The filling method adopts full bottle filling. After filling and capping (or twisting the cap), a bottle inverting device is added: the bottle body is tilted 90° to 180°, and the high temperature of the beverage itself is used to sterilize the inside of the bottle cap. Therefore, ultraviolet sterilization can also be used in the preliminary treatment of bottle caps. ? ? 2. Hot water spray sterilization?
Heat sterilization is one of the most traditional methods of food preservation. If microbial cells are heated to a certain temperature, the physiologically active substances in the cells (such as enzyme proteins, nuclear proteins, DNA, etc.) will be denatured and inactivated, thus losing activity and dying. The heating temperature and time to kill microorganisms vary significantly depending on the type of microorganism, cell physiological state, cell concentration, etc. For killing a specific bacterial species, increasing the sterilization temperature can shorten the heating time, while lowering the temperature requires extending the heating time. If the temperature is too low, the sterilization effect will not be achieved on some heat-resistant bacterial species. ?
Hot water spray sterilization uses a nozzle to spray hot water on the bottle cap in multiple directions. While sterilizing, it also removes dust on the inner and outer surfaces of the bottle cap.
During production of this method, the uncapped bottle caps travel in the bottle cap channel in the same direction. Multiple sets of nozzles are provided above and below the channel. The nozzles spray hot water from all directions on the advancing bottle caps. The temperature of the hot water It is the sterilization temperature, and the time it takes to receive the spray is the sterilization time. ?
Due to its high temperature resistance, the temperature of hot water for spraying can exceed 85℃ for metal caps, and the spraying time can be reduced as the temperature of hot water increases; for plastic bottle caps, the temperature of hot water for spraying is average. Control at 85℃. After hot water sterilization, it is necessary to spray sterile air on the bottle cap to promote drying of the bottle cap. ?
Hot water spray sterilization requires the supply of hot water and sterile air, and requires corresponding supporting equipment. It consumes heat energy and a small amount of water resources during production, and is equipped with commonly used general equipment. Hot water spray sterilization can be used to sterilize the bottle caps of tea drinks and fruit juice drinks filled at high temperature, and can also be used to sterilize the bottle caps of mineral water. ? ? 3. Ozone sterilization?
Ozone has extremely strong oxidizing properties. It can directly destroy the ribonucleic acid or deoxynucleic acid of the virus and kill it. Ozone can also damage the cell membranes of bacteria and mold microorganisms, inhibit their growth, and further penetrate and destroy the tissue within the membrane until the bacteria and mold microorganisms die. Ozone dissolves in water and has a very good sterilization effect in an environment with high humidity. Ozone water can also be used to sterilize bottle caps. Ozone water sterilization will be discussed later. The greater the concentration of ozone, the better the sterilization effect. When the ozone concentration is 4.0 mg/m3, the sterilization time generally takes 45 minutes to 1 hour. ?
Since ozone sterilization takes a long time, for an automated beverage production line with a certain production capacity, if both the sterilization effect and the bottle cap sterilization process must be completed continuously in the sterilization equipment, Sterilization equipment needs to be very large. In the actual production process, ozone sterilization of bottle caps is to place a certain amount of bottle caps in a large sealed space on an automated beverage production line with a certain production capacity, and then fill the space where the bottle caps are with a certain concentration of ozone and maintain it for a period of time. time. The number of caps placed is determined by the number of caps required to maintain production. The longer the sterilized bottle caps are stored, the greater the risk of contamination, so the storage time is generally no more than one week. The sterilized bottle caps need to be isolated from the outside world and sent to the cap conveyor when the cap conveyor needs caps. ?
At present, independent equipment that directly uses ozone sterilization is mostly seen in small cabinet-type bottle cap sterilization cabinets. This bottle cap sterilization cabinet has a small sterilization space, small production capacity, interval production, and non-automation. When using this kind of ozone sterilization cabinet, you need to manually move the sterilized bottle caps out of the sterilization cabinet and put them into the cap conveyor, which can easily cause secondary contamination of the bottle caps. Therefore, ozone sterilization is only suitable for non-automated production lines, or small production lines that have certain sterilization requirements for bottle caps. ? ? 4. Sterilization of sterilized water?
There are unstable elements in the sterilized water and they will decompose on their own. Sterilizing water sterilization uses this decomposition process (oxidation process) to oxidize microorganisms on the surface of objects to achieve the purpose of sterilization. ?
Common substances with strong oxidizing properties include: peracetic acid, ozone water and chlorine water. The instantaneous sterilization property of ozone is better than that of chlorine. At present, the sterilizing water for sterilizing beverage bottle caps basically uses peracetic acid and ozone water, the vast majority of which are peracetic acid. The greater the concentration of sterilizing water, the shorter the sterilization time required. For peracetic acid at 65°C and 2000PPM, the bottle cap can be sterilized in 30 to 60 seconds to meet commercial sterility requirements. Because sterilizing water has a short sterilizing time and good sterilizing effect, it is widely used in sterilizing bottles and caps of fruit and vegetable juice beverages. The main ways to use sterilizing water to sterilize beverage bottle caps are spraying and immersion. ?
1. The spray type uses multiple sets of nozzles to spray sterilizing water from multiple directions on the bottle cap to sterilize the surface of the bottle cap. The time the bottle cap is sprayed should ensure that microorganisms can be completely killed. The specific method is: the bottle caps after being sorted enter the bottle cap track in the same direction. There are multiple sets of nozzles above and below the track. Each set of nozzles can spray sterilizing water on the bottle caps from different angles. The sprayed sterilizing water is both Sterilizing the bottle cap also pushes the bottle cap forward along the track. ?
When using peracetic acid as sterilizing water, the bottle cap after spraying with sterilizing water needs to be rinsed with sterile water to remove the residual peracetic acid on the bottle cap so that the residual amount is less than Relevant standards; rinse with sterile water and then blow dry the cap with sterile air.
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When using ozone water as sterilizing water, since the products after the decomposition of ozone water are water and oxygen, there are no harmful residual substances. In theory, there is no need to process the bottle caps, but in the actual production process Because the outlet of the bottle cap sterilizer is very close to the capping machine, the residual ozone cannot be completely decomposed. Therefore, the bottle caps need to be rinsed with sterile water and dried with sterile air after being sterilized by ozone water. ?
Due to the linearity of the spray water, sterile water spray sterilization can be used to sterilize mineral water bottle caps, and can also be used to sterilize bottle caps during hot filling of tea beverages and fruit juice drinks. Hot filling adopts full bottle filling. After filling and capping, the bottle is poured and the cap is heated for internal sterilization. ?
2. Immersion type: The beverage bottle cap is completely immersed in sterilizing water, so that all internal and external surfaces of the bottle cap are sterilized by the sterilizing water. The soaking time should meet the time requirements for complete sterilization of the bottle cap. One method is: the bottle caps with the same direction are fixed on the bottle cap rack, and the bottle cap rack is connected to the chain. The movement of the chain drives the bottle cap rack into the sterilization pool containing sterilizing water and completely immerses the bottle caps in the sterilizing water. The soaking time should meet the time requirements for complete sterilization. Like the spray sterilization method, the bottle caps soaked in sterilized water also need to be sprayed with sterile water and sprayed with sterile air to make the bottle caps dry and sterile. ?
When using sterile water sterilization, the supporting sterilized water, sterile water and sterile air need to be produced and processed. There are many peripheral supporting equipment, high supporting costs and high consumption costs. Management requirements are high, so this sterilization process is generally used in aseptic cold filling of fruit juice drinks. ?
5. Sterilization of electrolyte?
Electrolysis uses inert electrodes to energize the liquid. An oxidation reaction occurs at the anode and a reduction reaction occurs at the cathode. At present, relevant foreign personnel have studied the electrochemical reaction between completely desalted drinking water and sodium chloride dilute solution to obtain a sterilizing solution in the anode area that has a sterilizing effect better than traditional sterilizing water. If the principle of electrolysis is directly used to sterilize bottle caps, transportation and warehousing costs can be greatly reduced, time and effort are saved, and it is safe and effective. ?
Summary?
After analyzing the above various bottle cap sterilization methods, different cap sterilization processes can be selected according to the ingredient characteristics and quality requirements of different beverages, as shown in the table: ?