Successful battle against bacteria in aseptic dosing
With the VARI-DOS-ASEPT, GEA TDS has achieved a quantum-leap forward in aseptic dosing – cost-effective thanks to requiring the smallest possible amount of the expensive lactase utilized.
More and more people tend to consume lactose-free dairy products that are free of milk sugar. By injecting the enzyme lactase into milk, lactose is broken down into fructose and galactose. The whole process to treat milk and to inject lactase must be completely aseptic. With the VARI-DOS-ASEPT, GEA TDS has achieved a quantum-leap forward in aseptic dosing – cost-effective thanks to requiring the smallest possible amount of the expensive lactase utilized.
There are two ways to produce lactose-free milk: either to inject lactase before the thermal treatment of milk or afterwards, when the milk has cooled down. The injection prior to the thermal treatment requires about 2 to 3 grams of lactase per litre milk, while the demand for lactase is dramatically reduced to merely 0.2 to 0.3 gram if the post thermal treatment method is applied. To avoid the invaded bacteria to revive again, which is possible e.g. through inserting an extra lactase injection needle into the product stream, the whole processing environment must be completely aseptic i.e. sterilized.
With the aseptic dosing station VARI- DOS-ASEPT, GEA TDS provides a safe and reliable way to dose small quantities of 0,2 – 3 g/kg of aseptic liquid products directly into the main aseptic product stream. The product to be dosed (e.g. lactase) is provided in aseptic containers similar to those used for infusions. Such a container consists of a pharmaceutical bag and a hose that is firmly connected to the bag. A dosing needle is fitted to the tip of the hose. All components have been previously sterilized. The empty hose is connected to the aseptic filling line upstream of the aseptic filler via the needle and a patented aseptic multi-function port valve. Thanks to two port valves the production can run continuously.
The aseptic port valve provides a small sterile space, in which all parts in contact with the main product are kept in overpressure and are sterilized at a temperature of at least 125 °C. The port valve is switched to the sterilization position by compressed air (without human intervention) and is then sterilized by steam passing through. The needle remains in the sterilization position, and the front third of the needle is also sterilized. Filtered, and thus sterile, compressed air automatically cools down the port valve to less than 50 °C after sterilization.
After cooling, a defined quantity of the product to be dosed is advanced in the hose right into the needle. The liquid is delivered by a hose pump, into which the hose must be inserted beforehand. The needle is then moved to the production position by the spring force of the port valve. The needle now reaches into the product chamber by approx. 5 mm. Separation is still maintained by the aseptic T-valve with special PTFE bellows which is connected to the port valve. The connection to the production stream is established by opening the bellows connection. The hose pump now conveys the quantity to be dosed in proportion to the flow rate of the main product stream and thus allows precise dosing of very small quantities. The dosing quantity is monitored by high-precision scales. In the event of a filler stoppage, the aseptic T-valve is simply closed again. The needle can remain in the production position, only the PTFE bellows connection is opened and closed. Alternatively, the needle can be switched to the sterilization position to allow rinsing with condensate. The condensate is produced by the integrated condenser in the system.
During cleaning, the cleaning agent supplied through the main product line also reaches the port valves as a result of the intermittent alternate opening of the aseptic T-valves. The result is efficient single-use cleaning. During the acid cleaning step the acid also flows through the condenser to clean it.
With the aseptic dosing station VARI- DOS-ASEPT, GEA TDS provides a safe and reliable way to dose small quantities of 0,2 – 3 g/kg of aseptic liquid products directly into the main aseptic product stream. The product to be dosed (e.g. lactase) is provided in aseptic containers similar to those used for infusions. Such a container consists of a pharmaceutical bag and a hose that is firmly connected to the bag. A dosing needle is fitted to the tip of the hose. All components have been previously sterilized. The empty hose is connected to the aseptic filling line upstream of the aseptic filler via the needle and a patented aseptic multi-function port valve. Thanks to two port valves the production can run continuously.
The aseptic port valve provides a small sterile space, in which all parts in contact with the main product are kept in overpressure and are sterilized at a temperature of at least 125 °C. The port valve is switched to the sterilization position by compressed air (without human intervention) and is then sterilized by steam passing through. The needle remains in the sterilization position, and the front third of the needle is also sterilized. Filtered, and thus sterile, compressed air automatically cools down the port valve to less than 50 °C after sterilization.
After cooling, a defined quantity of the product to be dosed is advanced in the hose right into the needle. The liquid is delivered by a hose pump, into which the hose must be inserted beforehand. The needle is then moved to the production position by the spring force of the port valve. The needle now reaches into the product chamber by approx. 5 mm. Separation is still maintained by the aseptic T-valve with special PTFE bellows which is connected to the port valve. The connection to the production stream is established by opening the bellows connection. The hose pump now conveys the quantity to be dosed in proportion to the flow rate of the main product stream and thus allows precise dosing of very small quantities. The dosing quantity is monitored by high-precision scales. In the event of a filler stoppage, the aseptic T-valve is simply closed again. The needle can remain in the production position, only the PTFE bellows connection is opened and closed. Alternatively, the needle can be switched to the sterilization position to allow rinsing with condensate. The condensate is produced by the integrated condenser in the system.
During cleaning, the cleaning agent supplied through the main product line also reaches the port valves as a result of the intermittent alternate opening of the aseptic T-valves. The result is efficient single-use cleaning. During the acid cleaning step the acid also flows through the condenser to clean it.
Source: GEA TDS
All content and features on this website are copyrighted with all rights reserved. The full details can be found in our privacy statement
