Sterile Air Feed

In order to safeguard touched food and beverage items, ingredients, packaging, and equipment surfaces from airborne microbial contamination, final or sterile air filtration eliminates germs from air or other gases. The filter type, necessary removal performance, gas type, and process characteristics such as gas temperature, flow rate, and supply pressure determine the selection criteria and sizing for these filters.

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The principle of water removal in aseptic air systems is that microfiltration membranes filter gases differently than liquids. Liquid filtration is a blockage filtration, where particles in the liquid are retained by the membrane as long as they are larger than the membrane pore size. In microbial aerobic fermentation process a large amount of sterile air is needed to supply the oxygen required for the growth and respiration of propagating bacteria.

Filled food basic processing method is mostly raw and auxiliary materials in the treatment of cooking into the packaging container, and then most of the products are in a certain vacuum conditions (or filled with inert gas) on the packaging container to seal, and then the sealed products are sterilized. So the manufacture of aseptic gas is especially important. How to control the manufacturing process of gas and the filtration process becomes the problem that manufacturers need to face.

How To Choosing the right filter for aseptic air filtration

Final or aseptic air filtration removes microorganisms from air or other gases to protect food and beverage products, ingredients, packaging and equipment surfaces that come into contact with them from airborne microbial contamination. The selection criteria and size of these filters depend on the filter type, desired removal performance, gas type and process parameters, including gas temperature, flow rate and supply pressure.

Sterile air membrane cartridge filters usually consist of PTFE media because of the high degree of natural hydrophobicity of this material. They have a fixed pore structure and there is no opportunity for bending of the filter media or unloading of contaminants, which is often a problem with depth filters. Membrane filters have very fine pores and a narrow pore size distribution, providing excellent retention under both liquid and aerosol bacterial challenge conditions. Membrane filters are almost always the first choice for sterile air filtration, especially in critical applications. The use of proven membrane filters provides the lowest risk, even in the worst case, process disruption conditions.

Because hydrophobic membrane filters provide excellent microbial retention under both liquid and aerosol bacterial challenge conditions, they are the preferred choice for sterile air filtration, especially in critical applications. Sterile air cassette filters are commonly used in compressed air supplies and as tank vent filters at atmospheric pressure. They can also be used for low pressure, low to medium volume airflow applications where economically feasible. It is important that sterile air filters be installed as close to the point of use as possible.

Depth cartridge filters, consisting of borosilicate microfibers, have low hydrophobicity, although they can be treated as hydrophobic. Depth cartridge filters are typically validated for aerosol bacterial challenges and cannot be validated for microbial liquid challenges, which is why they must be used in dry air to provide the desired retention performance. In general, depth filters provide higher airflow than cartridge filters.

What Sanitek can do in this procedure?

By ensuring the functionality and durability of your equipment, Sanitek’s tailored filtration solutions contribute to long-term cost savings on maintenance and operational expenses.

Sanitek’s market-leading filtration systems specialize in the removal of oil and particles from water streams, addressing environmental regulations or injection well standards. Our innovative offerings encompass oil adsorptive guard filters, high-efficiency coalescers, as well as disposable and washable solid cartridge solutions.

For this specific application, Sanitek designs and manufactures filter cartridges and filter housings. Our Oltek pleated filter cartridge and Oltek string wound filter cartridge stand out as ideal solutions for maintaining the required purity levels in this condition.