Flash pasteurisation for soft-drink production

In the Swiss town of Dietlikon; Coca-Cola Beverages AG has commissioned a PET-Asept system for bottling soft drinks like Nestea, and in future for handling carbonated beverages as well. Krones also supplied the entire process technology involved, including a syrup kitchen, a product flash pasteuriser, a mixer, a sterile water UHT system, CIP equipment, a clean-steam generator and a hygiene centre.
The syrup produced in the syrup kitchen is pumped via an automated valve rack to the Contiflow mixer, which operates at a speed of 27,000 litres an hour. The two-component system produces fruit-juice beverages, lemonades and carbonated mixed drinks. There is also an option for producing still beverages.
In order to extend the products’ shelf-lives, they are pasteurised before filling by means of a VarioAsept flash pasteuriser in a 20,000-litre sterile tank. During flash pasteurisation up to approximately 95 degrees Celsius, product spoilage germs are killed off or inactivated by the thermal loading. To enable the filler’s speed, which can vary between zero and 100 per cent, to be compensated for, a VarioStore sterile buffer tank is integrated between the flash pasteuriser and the filler, since the parameters of time, temperature and flow rate can be assured only when there is a continual flow of product. Mixing phases occurring during operation can be collected in a rework tank, and dosed into the mixer’s syrup line via a control valve.
The concept of flash pasteurisation using a VarioAsept is a flexible one: depending on the characteristics of the soft drinks involved, different pasteuriser variants will be deployed. Either product/product shell-and-tube heat exchangers can be used, or a plate heat exchanger, in order to achieve the optimum of efficiency in terms of energy and heat exchanger surface areas.