In the previous article, we have briefly introduced the standard cleaning process commonly used in breweries. In our layout design of breweries, we often recommend that our customers install CIP systems for equipment cleaning, but we also understand that some breweries did not plan to use CIP system cleaning in the early stage due to financial or space reasons. So how should a brewery without a CIP system clean its own beer equipment, and what cleaning agents should it use? In this short guide, we’ll discuss common standard cleaning chemicals.
peracetic acidFor most brewery equipment, the heaviest dirt will need to be rinsed first, then the remaining organics will be washed, rinsed again, and then sanitized.
Caustic Soda (Sodium Hydroxide) is a caustic alkaline cleaner that dissolves organic matter, making it ideal for cleaning brewery vessels, fermenters and plate heat exchangers. It is easily soluble in water, and formulated versions can be used more resistant to cold or heat. But it can also cause severe chemical burns and must be handled with care.
The cheapest form of caustic soda is solid, but this is not suitable for brewing use. Because solid sodium hydroxide is very harsh and can damage components and gaskets. Besides that, it is difficult to work with and its dust can damage the respiratory system, eyes and skin if inhaled. In brewing, sodium hydroxide is most often used in ready-to-use liquid form, with various additives added to improve cleaning, reduce foam, and protect various materials.
For equipment with relatively hot tanks, it is usually flushed with lye with a concentration of 1% at 80°C. If the dirt is serious, it can be increased to a concentration of 1.5%. The lye can be used at less hot temperatures when used to rinse fermenters, but lye cleans more effectively at hot or warm temperatures. It should be noted that sodium hydroxide will be neutralized by carbon dioxide, so make sure that the carbon dioxide in the tank has been removed before lye cleaning, so as not to affect the cleaning effect.
When cleaning with lye, it is best to recirculate it into the container via a spray ball to ensure a completely clean interior. Less concentrated lye (about 0.3 – 1%) can also be soaked in pipes and heat exchangers to slowly break down stubborn material. To clean the heat exchanger, it should be recirculated in the opposite direction of the beer flow, using a filter to catch any solids. For best results, recirculate in containers, pipes, heat exchangers, etc. for 30 to 60 minutes.
Peracetic acid is a strong disinfectant and fungicide commonly used in breweries to sanitize equipment. Higher concentrations (1%) of peracetic acid can be used to kill stubborn bacterial and fungal infections. However, it is more commonly used as a no-rinse sanitizer (at a concentration of about 0.1%). For best results, recirculate for about 30 minutes.
This is a dangerous acid and care should be taken to avoid splashing it on the skin and eyes as severe chemical burns may occur. It has a strong vinegar smell, but don’t try to smell it!
Peracetic acid can be broken down into acetic acid (vinegar) and oxygen. As such, it’s not ideal for bottle washing or other post-fermentation because it introduces oxygen into the finished beer.
Safe, no-rinse sanitizers are useful around breweries and have a variety of applications. It consists of food-grade phosphoric acid mixed with detergents and various agents commonly found in cosmetics to sanitize surfaces and equipment. It can be used to sterilize bottles and packaging equipment because, unlike peracetic acid, it does not break down to give off oxygen. Alternatively, it can be placed in a spray bottle to sanitize gaskets and equipment before use.
Phosphoric acid/nitric acid
This acid mixture can be used to passivate stainless steel vessels, but is most commonly used to remove beer stones and other mineral deposit buildup. It doesn’t have to be used often, maybe once or twice a year, and has to be rinsed thoroughly after use. On brewery vessels, use a mixture of approximately 1% acid and water between 60-70°C to remove beer stone deposits. Recirculate for about 15 minutes. It can also be used for pipe and heat exchanger cleaning.
For passivated fermenters and other stainless steel vessels, use a 0.5% – 1.5% mixture at room temperature and recirculate for approximately 15 – 20 minutes. Rinse thoroughly afterwards.