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Spores section
The efficacy of different chemicals to kill microbes within a biofilm isn't widely studied in the brewing or wine industries, partly because testing procedures are laborious and difficult to standardize. One study found that alcohol-based disinfectants (ethanol and isopropyl alcohol) were effective at killing microbes within a biofilm, and peracetic acid disinfectants were not as effective. A higher concentration of peracetic acid (from 0.25% to 1% of products containing 4-15%) was required to be more effective than lower concentrations. However, these disinfectants did not kill all of the cells without a cleaning regiment first. Yeast biofilms, in general, are more susceptible to cleaning chemicals than bacteria biofilms. Biofilms that are formed under static conditions (still or dried up liquid) are more resistant to disinfectants than biofilms that form under flow conditions (movement of liquid) <ref name="Wirtanen_2001" />.
===Spores===
Some species of fungi and bacteria can form spores. Fungi form spores in order to reproduce sexually. Their sporulated forms are not a mode of protection from disinfectants and are therefore killed by normal sanitation methods. Bacteria form spores as a mode of survival. For example, some dangerous types ''Clostridium botulinum'' spores require 250°F (121°C) for 3 minutes to be killed, which is the requirement for canned goods <ref>[http://www.jfoodprotection.org/doi/abs/10.4315/0362-028X-45.5.466?code=fopr-site Differences and Similarities Among Proteolytic and Nonproteolytic Strains of Clostridium botulinum Types A, B, E and F: A Review. RICHARD K. LYNT*, DONALD A. KAUTTER and HAIM M. SOLOMON. 1982.]</ref><ref>[http://beerandwinejournal.com/botulism/ Chris Colby. "Storing Wort Runs the Risk of Botulism". Beer and Wine Journal Blog. 04/17/2014. Retrieved 04/04/2018.]</ref>. Spore-forming species of bacteria, however, are not considered beer spoilers <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2047716495256554/?comment_id=2047776558583881&reply_comment_id=2048688798492657&comment_tracking=%7B%22tn%22%3A%22R%22%7D Bryan Heit. Milk The Funk Facebook thread on yeast and bacteria spores and brewery hygiene. 04/04/2018.]</ref>. Thus, the challenge of killing yeast or bacteria spores is irrelevant in most beer and wine production. There are some extraneous brewing methods where bacteria spores should be considered, for example [[Wild_Yeast_Isolation#Safety|wild yeast isolation safety]], [[mold]] formation during fruit fermentation or barrel aging, and the long storage of wort produced by the [http://beerandwinejournal.com/botulism/ "No Chill" homebrewing method].
===Methods For Avoiding Contamination===