Incoming mains or borehole water would typically be filtered via an RO system for brewing liquor production and boiler feed. Microbreweries and craft brewers will often filter the incoming water with carbon cartridges to remove chlorine and other chemicals, which could affect the taste of the beer.
Bag filtration is commonly used to remove bulk solids, e.g. grist and bulk yeasts.
Bulk yeast and diatomaceous earth removal before beer is sent for packaging usually uses 1µm – 5µm cartridge filters.
During the filling of sterile beer kegs and bottles, the beer is typically filtered to 0.45µm either with one pleated cartridge or a two / three stage system (typically 5µm > 1µm > 0.45µm). This is for clarification and to prevent microorganisms spoiling the final packaged product.
Beer is stored in sterile tanks, which have 0.1µm or 0.2µm air vent filtration to prevent ingress of bacterial contamination.
Rough and Trap Filtration
Rough and Trap filtration techniques are typically used in the production of all spirits including Whisky, Gin, Vodka, Brandy and Liqueurs.
After distilling, the spirit is reduced in strength by diluting with Reverse Osmosis (RO) or De-Ionised water (DI).
At the bottling line, the spirit is filtered (bottling line guard filter) to ensure no contaminants get through to the final product; this is normally 10µm but can be larger in more viscous spirits/liqueurs. Bottle rinsing often uses the product, which will be filtered to 10µm.
Mature whisky is disgorged from barrels and filtered to about 50µm to remove barrel char. Bags or depth cartridges are used.
The whisky is then chill filtered using sheet filtration, in most cases; to remove fatty esters (this prevents the whisky becoming cloudy when water is added) this process is often preceded by cartridge filtration (10µm – 20µm) to improve the life of the sheet filters.
The method used to produce white, red or sparkling wine is similar although the vintner (winemaker) will adapt the process to suit the variety of grape and / or the desired final result. The various processes often include harvest, crush & macerate, press, cold stabilisation, fermentation, racking, aging, clarification, stabilisation and bottling.
Incoming water is often filtered with Depth cartridges to 5µm and then disinfected using a UV system followed by a 0.2µm pleated cartridge to remove bacteria.
Pleated cartridges are used during the clarification and stabilisation stages to ensure a good appearance, flavour and quality for a long shelf life for the product. The wine is processed through rough filtration during the clarification stage to improve the visual appearance of the wine where large particles and suspended solids are removed reducing turbidity or haze.
The bio-burden reduction and sterile filtration stages use 0.45µm – 0.65µm pleated cartridges to remove remaining yeast and other spoilage organisms that can affect the wine in the bottle.
A wide range of soft drinks are produced, including flavoured waters, carbonated drinks and natural fruit juices. Filtration is used in the manufacture of these drinks to ensure high product quality in appearance, flavour, customer safety and shelf life.
Rough filtration methods, typically using bag filters, are used with natural fruit juices and syrups to remove fibrous organics, sediment or gelatinous particles. This Rough filtration economically protects any Sterile filtration stages from premature blocking.
Incoming water is filtered and treated with a combination of depth, surface, UV and RO depending on the source. The treated water and the filtered juice/syrup are then blended, mixed and packaged.
Sterile filtration using absolute rated certified cartridge filters make product water and the final packaged beverage free from sediment, parasites, bacteria and improves the appearance. The air in storage tanks and gases such as CO₂ used for carbonation, must be free from particles and bacteria also, this requires PTFE hydrophobic cartridges that are resistant to sealing from splashes.
Solutions to the issues of site protection from parasites, unwanted tastes and effects on active ingredients from chemicals in the water, high particle levels in natural product ingredients, hazing and visual purity of the final product, are all offered with Fileder’s filtration recommendations.
There are generally three types of bottled water, which are described as follows, in addition to the following there is also flavoured waters, which in general have similar types and levels of filtration to bottled water but have added problems due to potential introduction of sugars, which could cause bacterial problems.
Spring water typically comes from an underground aquifer from which the water flows naturally to the surface. Bottled water production facilities can use external force (i.e., pumping) to bring the water to the surface for bottling.
Spring water is of high quality and commonly filtered to 1µm or 0.2µm before bottling to protect against cryptosporidium or bacteria.
Mineral water must naturally contain at least 250 ppm of total dissolved solids. The concentration of minerals and trace elements in mineral water might vary due to natural cycles of fluctuation, but should remain relatively constant over time.
Similar filtration levels as for spring water but the filtration must not affect the mineral levels.
Bottled water could be described as water that is bottled but is neither spring nor mineral water and is generally produced from a large source of water such as mains water or a spring, which is not pure enough to sell as spring water.
The water is usually filtered by reverse osmosis to remove any impurities and then minerals are added to meet a specific requirement.
The water is then filtered to 1µm or 0.2µm before bottling to ensure the integrity of the finished product.