xxc The key lies in oxygen uptake.
Demonstrate a variety of information, domestic and international beer market is about to enter a plastic bottle of beer, including the sale of a small flask of hot filling period. It is reported that in 2005, PET bottle beer filling beer sales volume worldwide will reach 3.5%.
Ideal filling: isovolumic filling system.
In general, beer is the one by the bottle filling machine filling the plastic bottle. First rinse process to remove the plastic bottle blow molding machine blow the residual substances. As the oxygen in the wash water is always saturated,glue stick and every drop of residual moisture will increase oxygen to the beer. Therefore recommend the use of an electric pneumatic control of dual-channel-type washer, the plastic bottle washed, then air dry sterile.
On the filling process, the use of sensors with a constant volume flow meter filling system is increasingly evident. This process is suitable for plastic bottles in a precise size of the container class. Aseptic filling technology for PET bottle, Krones will use this and other capacity-type filling system. Because it uses a long tube filling system, in the liquid surface, the gentle filling, plus the cover prior to the red ring gas cylinder bottles,glue gun and then clean the gas channel carbon dioxide emissions preparedness pressure, so that oxygen can be maintained very good value. PET bottle will bottom out air exhaust, very good. As the valve is no spring mechanism, thus creating a very good health design.
Krones VODM-L-PET bottle filling system from the first use of the jet. This is to avoid using dynamic seals Rick Lance, instead of using the folded airbag static valve seal, and then to clean the gas back pressure only after the slow filling and fast filling. There may also take the bottle slowly filling, filling a large bottle of the way fast. After filling, still waiting for a specific period of time so that large bubbles floating on the surface, relief was only plastic bottles, bottles decline, then the emptying of the filling tube. CIP cleaning procedure is most suitable for use in this filling system. By the electrical control system to CIP cleaning procedures set free. This procedure ensures the optimal flow conditions.
Advantages and disadvantages of plastic bottles.
Filling plastic bottles of beer both advantages and disadvantages. The advantage clearly is light weight, easily broken, design flexibility, transparency, and can shape the exact size. But plastic bottles can not be completely in the filling machine vacuum, so it's not airtight. As atmospheric pressure in the gas exchange plays a major role, oxygen will penetrate plastic bottle (product should be reduced in oxygen content), and release carbon dioxide.
Plastic bottles can not be over-heating, which means that generally can not be pasteurized on the plastic bottles. It is the head strength is limited, which affects the choice of cap. In the compression, heating, its volume will change, and the bottom uplift, easy to tip over the bottle. Dimensional accuracy of plastic bottles generally higher than the glass, but it is not the standard container requirements point of view. Ambient temperature during transport, light and handling will be an impact on the plastic bottles. Other factors include the production of plastic bottles, raw materials, the selected design and the blowing process and the contraction into the bottle.
Type of cap.
The choice of the bottleneck cap category within the Ministry of the air, oxygen, and the total shelf life of beer, a great influence on the shelf. The current market offers a variety of plastic stopper cap, aluminum cap, crown cap, pull-type rotary-type sealing cap and pre-cap. These caps have their own advantages and disadvantages.
Pre-seal style cap.
There are two ways to choose from. One is the high-pressure spray irrigation, the individual will be placed in pre-sealed bottle, after blowing thread, check the location of pre-sealed, then sealed the original cap.
The second type is the built-in pre-sealed cap. Screw on the cap when the pressure seals to be built to the mouth of the bottle, then screw injection, and then tighten the cap.
Long-and short-tube filling machine tube filling machine in the oxygen content differences.
Filling in the beer bottle or plastic bottles to PET, the oxygen content is an important indicator. To make the filling system and a relatively bottle category, list the following theoretical values. Of course, these theoretical values with the actual situation may be biased. Numerical calculation by 500 ml / bottle, 5.5 grams of carbon dioxide / l, filling temperature of 12 ℃ calculation. Assuming the initial oxygen content in beer is 0.05 mg / L (flushing the bottle), the purity of carbon dioxide within the bottle is assumed to be 96% ~ 98% (with the red bottles of water.)
Long and short tube machine tube machine difference is: in the short-tube filling machine, bottle washing the purity of carbon dioxide 95%, while in the long tube filling machines, 98% purity of carbon dioxide, oxygen tubes in a short amount of filling machine is 0.08 mg / l, while the length of the machine was 0.03 mg / liter. The latter is assuming a pure CO 2 prepared with pressure VODM-L-PET filling machines. Beer in both bottles into the filling machine is high, the bottleneck space, air content of 0.35 mg / bottle.
Use of crown cover, screw-type cap or pull-style cap with pre-sealed, the oxygen amount to about 0.18 mg / l (based on Wuli Xi and Wei Laha Uhlig & Vilacha law).
Another case, if you are using aluminum cap, bottle seal must take into account the air volume of about 10.5 ml. But also estimated that in extreme adverse circumstances, 30% of the total air being pressed the bottle. The remaining leakage along the threads, resulting in the actual amount of air added to 3.15 ml.
No advance in the use of sealed plastic bottle, this is even more apparent. Because the plastic bottle and aluminum screw cap the contrary, the bottle is threaded mouth of the bottle cap screw thread and a small gap between, estimated that only half of the air is leaking through the threads. Therefore, the worst-case scenario would increase the amount of 5.25 ml air. According to this view, should be as far as possible with the pre-sealing cap, screw-type cap or crown cap pulled.
The total volume of oxygen bottles and caps with the relationship between the categories.
From a series of experiments, Krones will be used crown cap bottles and 500 ml 500 ml PET plastic bottle capping the amount of oxygen measurement compared together: the growth within the liquid oxygen (Unit: mg / l), the bottleneck of the oxygen in air space volume (Unit: mg / l) and total oxygen (oxygen volume called TPO, Unit: mg / l). Inflow of oxygen from the tanks reached the Qing 0.05 mg / liter. Can be clearly seen by comparing the glass and PET bottles, there is a big difference between, including PET bottle, from inside the space bottleneck oxygen pressure is the highest.
Bottlenecks in the amount of pressure and filling, and therefore inversely proportional to the bottle size and value, the larger the bottle the better.
Apart from market demand aside, in order to maintain the pure flavor of the filling material, aspects of these processes will be filling bottles and the caps on the selection of an impact.