Press release from February, 28th, 2018
From experience: typical flux ranges of tubular ultrafiltration membranes during the clarification of different fruit juices
The performance of UF membrane modules in the sense of stable and high permeate fluxes when clarifying juices is depending on a couple of decisive parameters. Some of the most important influencing variables are: kind of juice, processing temperature, sugar content (°Brix) und the use of filter aids.
As a rule of thumb for cross-flow operated ultrafiltration applies: the higher the sugar content, the lower the permeate flux which can be expected. In addition, when processing light juices, flux ranges tend to be higher compared to the fluxes of dark juices (with the exception of very acidic fruits such as limes and lemons). Even though they are typically filtered “more open” to reduce color loss to a minimum, dark juice fluxes are usually at the bottom of the scale.
A real life example is the clarification of (raw) apple juice, which has to undergo an enzymatic pre-treatment step as well as a depectinisation process upfront the ultrafiltration. The processing temperature should be around 50 °C while the sugar content is around 10° to max. 20°Brix. Ideally, the Brix level can be adjusted to anything between 13° and 14° to keep fluxes high (> 90 l/m²h possible) and stable. A decrease or increase of the sugar content has direct impact on the filtration performance, in a best case scenario a flux of up to 120 l/m²h is possible.
Our application engineers have long-time experience in the area of ultra- and microfiltration of all different kinds of fruit juices. Please get in touch with us today, we´re looking forward to discussing your project!
For further information contact:
Tel: +49 (0) 6196/653211