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===Methods For Avoiding Contamination===
====General Approaches====
* Use 180°F/82°C hot water for 60 minutes to disinfect stainless steel or heat tolerant materials.
* For any plastics that cannot be treated with heat, especially tubing, keep separate plastics for use with ''Lactobacillus'', ''Brettanomyces'', and ''Saccharomyces cerevisiae'' var. ''diastaticus''.
* Replace rubber and plastic parts such as gaskets as often as recommended by the manufacturer.
* When operating a commercial brewery with clean beer production alongside sour beer production, invest in a quality control lab and procedures.
* Use a separate packaging system for sour beer unless the packaging system can be sanitized with hot water or caustic (foam disinfectants that are often used in packaging lines have been reported to be not as effective against removing biofilms).
====Reducing Microorganisms====
Several generalized procedures are used for limiting the number of unwanted microorganisms. These include acid washing yeast that is re-pitched (kills bacteria but not wild yeast), keeping beer cool (slows the growth of microbes in general), filtration (removes yeast), pasteurization (kills vegetative cells in the finished beer, but not spores - most beer spoilers are killed at 15 [http://wiki.zero-emissions.at/index.php?title=Pasteurization_in_beer_production pasteurization units (PU)] and all are killed at 30 PU using a recommended pasteurization temperature of 66°C ), and aseptic or hygienic packaging. Packaging systems should be frequently flooded with hot water between 80-95°C or saturated steam (every 2 hours in the summer and every 4 hours in the winter). UV light or disinfecting chemicals are also used. The filler and crowner should be disinfected frequently as well. Packaging in an aseptic room with HEPA filtration and higher air pressure within the room compared to outside, along with special clothing, is another method that larger breweries use to remain aseptic <ref name="storgards_2000" />.