Cleaning and Sanitising for brewers
Cleanliness is one of the most important aspects for all food preparations; this is even truer for Brewing. In Brewing we provide good growing conditions for yeast which are also good conditions for other unwanted microorganisms, especially wild yeasts and bacteria. Cleanliness must be maintained to a very high standard through each stage of the brewing process, to avoid spoilage. Many otherwise excellent brews are destroyed as a result of wild yeast and bacterial infections by taking shortcuts.
The basic Rules for cleaning and sanitising
The definition of sanitisation is to reduce bacteria and contamination to insignificant and manageable levels. The terms clean, sanitise, and sterilise are often used interchangeably but should not be. Items may be clean but not sanitized. Here are the definitions:
Cleaning is the process of removing all the dirt and bio-films from a surface thereby removing all sites that can harbour bacteria. Cleaning is usually done with a correctly formulated brewing detergent (no perfumes, enzymes, or chlorine) and elbow grease. None of the sanitising agents used by home brewers are capable of eliminating all bacterial spores and viruses. The chemical agent’s brewer’s use will clean and sanitise but not sterilise. However sterilisation is not necessary. Instead of worrying about sterilisation, home brewers can be satisfied if they consistently reduce these contaminants to negligible levels.
All sanitisers are meant to be used on clean surfaces. A sanitiser’s ability to kill microorganisms is reduced by the presence of dirt, grime and organic material.
Organic deposits can harbour bacteria and shield the surface from being reached by the sanitiser. So it is up to you to be sure that the surface to be sanitised is as clean as possible.
The cleaners
Cleaning requires a certain amount of scrubbing, brushing and elbow grease. It is necessary because a dirty surface can never be a completely sanitised one. Deposits can harbour bacteria that can spoil beer. The ability of any sanitising agent to kill bacteria is reduced by the presence of any organic matter, so prior cleaning is necessary to complete sanitation. Below is a list of cleaners and their pros and cons
Dishwashing liquids
These products mostly contain scents/perfumes that can be absorbed into our brewing equipment and released back into beer. Additionally some detergents are difficult to rinse and leave behind a film that can be tasted in beer and ruin head retention. SUGGEST YOU AVOID THEM.
Bleaches
Both liquid and powdered chlorine bleaches often also contain perfumes and other additives such as enzymes and fillers. The one to use for brewing purposes is the Pink Stain Remover. As its name suggests it is used for cleaning stained equipment or if you have acquired beer bottles that need a thorough cleaning. It is very effective used in this way but is very hard on equipment (and your clothing) so its use should be limited and needs extra care when rinsing.
Sodium Meta silicate (brewers detergent)
Once widely available this cleaner (not to be confused with Sodium meta bi-sulphite which is a now superseded sanitiser) has been a very effective brewing cleaner for many years. However it is now being replaced by the easier to use, liquid, nontoxic spray on cleaners such as Morgan’s Low suds and Brewcraft’s Brewclean. Spray on cleaners greatly reduce the amount of cleaner required and are quite economical.
Automatic Dishwashers
We’re often asked about using dishwashers, but there are a few limitations.
The narrow openings of hoses bottling valves and bottles usually prevent the water jets and detergent from effectively cleaning the inside. If it does get in there is no guarantee it will be rinsed out. And lastly the drying additives can ruin head retention in beer. These work by coating the surface in a chemical film so droplets won’t form preventing spots. The wetting action destabilises proteins that form the bubbles. It is for this reason that beer glasses should not be washed in the dishwasher.
The sanitisers
Once your equipment is clean, it is time to sanitise it before use. All surfaces that will contact your brew need to be sanitised such as fermenter, lid, o-ring, grommet, airlock, stirrers, thermometers and hydrometers, work surfaces, can openers and hands etc.
Percarbonates and peroxides
Sodium per carbonate is sodium carbonate reacted with hydrogen peroxide and it is a very effective sanitiser for all types of brewing equipment. Hydrogen peroxide will effectively sanitize surfaces and containers that are already clean. As with all sanitizers, the effectiveness of hydrogen peroxide as a sanitizing agent is compromised by organic soil. Use these cleaners according to the manufacturer's instructions, but generally use 30 ml per litre and rinse after cleaning. One of the best properties of the per carbonate family in that they are environmentally and septic system friendly and need little or no rinsing. I am often asked about using nappy cleaning powders such as nappy san, this product does contain sodium per carbonates (typically about 23%) but also contain many phosphates, enzymes and perfumes, which work well in the nappy bucket but you won’t catch me drinking from it!
Other forms of nappy cleaner can contain Chlorinated Trisodium Phosphate, which is a heavy duty cleaner and a sanitiser. It’s certainly effective, but it’s also very harsh on equipment and should only be used occasionally on the toughest jobs.
Sodium percarbonate is a very effective cleaner and santiser for stainless steel kegs and stainless steel brew pots as used by grain brewers. Mixed with a blend of 30% sodium metasilicate, it’s exceptional as a brewery cleaner and sanitiser.
Acid Sanitisers
Phosphoric Acid and Sulphonic Acid mixes are very effective sanitisers that are also no rinse. The perfect partner for rotating with per carbonates/peroxides. A little goes a long way, a bottle will last for a long time if used according to instructions. They also have some other advantages in that contact time is low for a high organism kill rate and that if small amounts of residue are left behind, they basically break down to become yeast nutrients. At the present time, these acid based sanitisers tend to cause foam to form when aggitated in mixing them. The foam is not rinsed off. Ensure a wet surface contact time of at least 2-3 minutes, pour off or shake ff excess moisture and simply use the equipment foam and all. The foam residues will be broken down by yeast and consumed.
Sodium Meta bisulphite
It is used as a food additive, mainly as a preservative and is sometimes identified as E223.
E numbers are codes for food additives and are usually found on food labels throughout the European Union….
It may cause allergic reactions in those who are sensitive to sulphites and should not be used by asthmatics. It was commonly used in home brewing to sanitise equipment. When mixed with water, sodium metabisulphite releases sulphur dioxide.
Sulfur dioxide is the chemical compound with the formula SO2…. (SO2), a pungent, unpleasant smelling gas that can also cause breathing difficulties in some people. It should not be used at all in households where asthmatics live as it can rapidly cause a fatal asthma attack and is capable of causing fatal allergic reactions in people who are hypersensitive to sulphur based compounds. For these reasons, in beer brewing applications, sodium metabisulphite has fallen from common use in recent times. It's still widely used in wine making.
Hydrogen peroxide is a very pale blue liquid which appears clear in a dilute solution, slightly more viscous than water….
becoming more popular for effective and odourless sanitising of equipment. Products available include, Morgan’s Sanitise, Brewcraft’s Brewshield and Sanitise sachets. Used in the correct concentration, it is an effective sanitiser on clean surfaces but once diluted to working strength, it's effectiveness decreases within an hour and has no sanitising properties after 24-48 hours.
Cleaning your equipment means that you have removed all of the visible dust, dirt and residue on your equipment, but not living organisms.
Sanitising means you have treated your equipment (post cleaning) with a chemical solution that will eliminate virtually all spoilage organisms (moulds, wild yeasts, bacteria).
You MUST CLEAN your equipment BEFORE sanitising the equipment, since it is difficult to properly sanitise equipment with visible residue on it. The terminology “sterile” is the complete elimination of spoilage organisms, and is not realistic in the home brewing environment. Essentially, to sterilise, you need to use an Autoclave (high pressure steam steriliser).