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===Methods For Avoiding Contamination===
====General Approaches====
* Use the maximum concentrations and exposure times suggested by the manufacturers of any given cleaning/disinfectant product.
* Clean first using an effective cleaner, and then apply a disinfectant/sanitizer as a second step.
* Use 180°F (82°C) hot water for 60 minutes to disinfect stainless steel and other heat tolerant materials.
* For any plastics that cannot be treated with heat, especially tubing, keep separate plastics for use with ''[[Lactobacillus]]'', ''[[Pediococcus]]'', ''[[Brettanomyces]]'', and ''[[Saccharomyces#Saccharomyces_cerevisiae_var._diastaticus|Saccharomyces cerevisiae'' var. ''diastaticus]]''.
* Replace rubber and plastic parts such as gaskets as often as recommended by the manufacturer or when wear is apparent.
* 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).
* The more surface area that equipment has, the more prone it is to biofilm formation. Horizontal surfaces are more prone than vertical surfaces to biofilm formation.
====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" />.
# Leave in contact with surfaces for 5 minutes or more.
# Optional: warm the Star San and water solution to 40°C/104°F.
'''Five Star PBW'''
PBW is a replacement for caustic and is much safer to use and dispose of. It is non-corrosive and safe to use on stainless steel and plastics. We are not aware of any studies that examine the efficacy of P.B.W. to remove biofilms, nor any other percarbonate-based cleaners efficacy in a brewing environment.
Tips for using PBW on equipment that may have had biofilm formation <ref>[http://www.fivestarchemicals.com/wp-content/uploads/PBWTech.pdf "PBW Tech Sheet". Five Star Chemicals. Retrieved 04/19/2018.]</ref>:
# For circulated cleaning, use 3 ounces per gallon of 180°F for 30 minutes.
# For non-circulated cleaning, use 8 ounces per gallon of 180°F water (if using this product on plastics, heat the water that is mixed with the PBW to be as hot as the manufacturer of the plastics recommends), and soak overnight.
# Rinse thoroughly with hot water (cold water may not remove some of the residual chemicals).
==Quality Control==
* Flow cytometry.
Beer adapted strains of ''Brettanomyces'' and lactic acid bacteria have been found to be more difficult to culture on agar than when they are not adapted to the environment. Malt agar has been shown to be more effective at showing growth than some other types of agar (Dekkera Medium, Universal Beer Agar, Potato Dextrose Agar, and Beer Agar). [[Laboratory_Techniques#Saccharomyces|YPD]] with 10 ppm Cycloheximide was not tested in the study, but Nick Impellitteri, the owner of [[The Yeast Bay]], reports that this media works well for him <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2047731471921723/?comment_id=2047735648587972&reply_comment_id=2047763545251849&comment_tracking=%7B%22tn%22%3A%22R0%22%7D Nick Impellitteri. Milk The Funk Facebook post on the ability of different media to grow beer adapted ''Brettanomyces''. 04/03/2018.]</ref>, and DBDM media has also been reported to work well for growing ''Brettanomyces''. In addition, it is recommended that 100 mL samples are taken since beer adapted contaminants are harder to grow on media, and at least 7 days of incubation time should be allowed for ''Brettanomyces'' to show signs of growth <ref>[https://www.tandfonline.com/doi/abs/10.1094/ASBCJ-2008-0917-01 Effects of Beer Adaptation on Culturability of Beer-Spoilage Dekkera/Brettanomyces Yeasts. Koji Suzuki, Shizuka Asano, Kazumaru Iijima, Tomoo Ogata, Yasushi Kitagawa & Tsunehiro Ikeda. 2018.]</ref> (see also [https://www.facebook.com/groups/MilkTheFunk/permalink/2047731471921723/ this MTF thread)].
Advanced beer-spoiler detection medium (ABD) has been shown as a more effective growth medium compared to other media when attempting to grow beer-adapted bacteria such as hop tolerant strains of ''Lactobacillus'' that don't grow well on other media.
==Quality Improvement==
(To do)
'''Quality improvement''' is a formal and systematic practice of analyzing ongoing processes and identifying problems or places for improvement.
* [https://info.moravia.com/blog/quality-assurance-quality-control-and-quality-improvement-explained "Confused? Don’t Be! Quality Assurance, Control and Improvement Explained" by Lee Densmer.]
==See Also==