Filtration Stages In The Beverage Industry
Filtration is a crucial step in beverage production. While there are many types of beverages, they all require critical process operations to ensure the integrity of the production process and to consistently produce the perfect beverage. A proper filtration system is critical in ensuring the biological safety, quality, and shelf-life of the product, as well as protecting process equipment. Global Filter designs and manufactures vessels and filter elements used in the beverage industry. Our expertise enables us to optimize your manufacturing process.
There are 3 main filtration stages in any beverage production:
- Pre-filtration (bulk filtration)
- Fine filtration (clarification)
- Sterile filtration (cold stabilization)
Pre-filtration stage
Removes all unwanted large particles (coarse filtration) to make the beverage visually clear. For example, in the manufacture of soda, some raw products used may contain particles that can affect the quality and aspect of the final product. Bag filters and depth cartridges are commonly used for this step.
Fine filtration stage
Depending on beverage composition (solid content, turbidity, micro-organisms), a pleated cartridge will be used, with a pore size rating of 1 to 3 micron. The polypropylene and glass fiber pleated cartridges have a low pressure drop, high load capacity and efficiency. The glass fiber pleated cartridges also assist in haze removal due to the media’s inherent positive charge. This fine filtration step protects the membrane filter from being overloaded with particles and prematurely clogging.
Sterile filtration stage
Before bottling, the third (final filtration) step provides clarity to the beverage while removing residual yeasts, and microbial contaminants. Potentially infectious agents like Cryptosporidium, Giardia Lamblia, Kieselguhr and diatom powders are targeted for removal as they can potentially induce bottled fermentation, haze reformation, interfering with the beverage’s preservation. For microbial contaminant removal, 0.45 or 0.8 micron rated PES membrane cartridges. Removing the microorganisms provides a stable product, free from microbial contaminants. This stage uses membrane cartridges as an effective alternative to flash pasteurization, particularly in small and medium-sized companies where an economical solution will bring a major advantage. It is also used in manufacturing plants where taste is paramount (filtration will not affect the taste of the beer).
In addition to these three main filtration steps, it is also crucial for the beverage quality and regulations to be followed. Microbial contaminants must be sterile effluent free, providing cleanliness to wash/rinse water and fluid utility lines. Fermentation and holding tank vents should also utilize filtration to remove contaminants from ambient and process air.
Some beverage productions also require additional filtration steps: For instance, in the production of sodas, syrup can be diluted with water. This water should be filtered (when permitted) to 0.2 μm in order for the product to be stable for consumer protection and shelf life. Strongly asymmetric membranes are the recommended filter for this step. They are strong and robust membranes, able to withstand several cycles of sanitization. To properly protect these membranes, processes combining pleated and depth cartridges are the best pre-filtration solution for mineral water.