Importance of Proper Sanitation Techniques
It is of the utmost importance to strictly follow proper
sanitation procedures when brewing or bottling beer. It is commonly accepted
that most bad batches of homebrew can be traced back to improper or inadequate
cleaning techniques. It is so easy to properly clean your equipment, and takes
such little time, that one really has trouble understanding why some people
don't do a proper job of it.
After all, even the most sophisticated high-tech brewery will produce swill if
the proper sanitation techniques are not adhered to.
Sanitize vs. Sterilize
First of all, lets get our terminology straight - you are not sterilizing
anything. That it simply not an option for even a mega-brewery, let alone for a
homebrewer. What you want to do is sanitize, or get rid of the vast majority of
any harmful bacteria, but not all of it. Anything whatsoever that comes in
contact with your beer should be first cleaned, then sanitized. The only
exception from this rule are things that will be boiled. For example, although
you'll want to give your brewpot a good wash with water and dish detergent
beforehand, you won't need to sanitize it since the boiling liquid will take
care of that. The same applies to any spoon used to stir the boiling wort.
However, spoons used to stir the cooled wort should most certainly be cleaned
and sanitized.
First clean the equipment with a good mild dish detergent, then rinse well with
warm to hot water. The lemony-type anti-bacterial detergents do a wonderful job.
Remember, unless your equipment has first been cleaned well, the sanitizing
agent won't be able to do it's work properly. For example, if there is a scum on
the wall of your primary fermenter, bacteria will certainly find it and take up
residence there. After all, that's bacteria food! Furthermore, the sanitizing
solution will not be able to get at the bacteria because they will be protected
by the scum on which they are feeding.
So always wash your equipment first, then sanitize it.
When cleaning, please be careful not to scrub any plastic surfaces with
abrasives, as this will scratch the plastic and provide a wonderful breeding
ground for unfriendly micro-organisms. Instead, just use a dish cloth or sponge
to do the job.
High-Powered Cleaning Agents
There are a few newcomers on the cleaning scene which have become widely
available to homebrewer. The household wonder-cleaner OxyClean (or any of the
copycats) uses powerful oxygen to eat away just about any kind of brewing grunge
imaginable, including the post-fermentation residue almost always found on
fermenter walls. As little as a tablespoon per 20 liters / 5 US gallons will eat
just about anything. Higher concentrations can be used for faster cleaning, but
very low concentrations are extremely effective overnight. If OxyClean cannot
eat it, then Straight-A from Logic, Inc or Powdered Brewing Wash (PBW) from Five
Star Chemicals almost certainly will. Both are almost identical formulations and
were specially formulated for the brewing industry. You can literally watch the
stuff eating through just about any kind of organic material imaginable. Use
according to the manufacturers instructions.
All of OxyClean, Straight-A and PWB can leave a slick film behind on equipment
so you have to rinse extremely well after using them. They can be stored in a
sealed bucket and remain effective over a few days to a week. Though OxyClean
will not last as long as the others this way. Since Straight-A and PBW are a
fair bit more expensive than OxyClean, and since OxyClean is so effective
anyway, some use OxyClean for most cleaning applications and only haul out the
PBW when OxyClean can't handle it. It is a good idea to always use PBW for
cleaning a wort chiller, because that is precisely what it is designed for -
cleaning brewing equipment where you cannot see the surfaces.
Cleaning and Sanitizing Agents
Agent |
Use |
Mixture |
Contact |
Rinse |
Environment |
OxyClean |
clean |
1-3 tablespoons per 20
liters |
as required |
Extremely Well |
friendly |
PBW |
clean |
1-3 tablespoons per 20
liters |
as required |
Extremely Well |
friendly |
Straight-A |
clean |
1-3 tablespoons per 20
liters |
as required |
Extremely Well |
friendly |
bleach |
sanitize |
4ml / liter - 1 tbsp /
gallon |
15 minutes |
Extremely Well |
unfriendly |
diversol |
sanitize |
4ml / liter - 1 tbsp /
gallon |
15 minutes |
Yes |
unfriendly |
iodophor |
sanitize |
read instructions |
60 seconds |
No |
unfriendly |
Star San |
sanitize |
read instructions |
60 seconds |
No |
friendly |
B-Brite |
both |
4ml / liter - 1 tbsp /
gallon |
15 minutes |
Extremely Well |
friendly |
Sanitizing Agents
There are several very effective sanitizing agents which the homebrewer can use
in his or her brewery. Some are extremely inexpensive, yet harmful to the
environment, while others are a bit more expensive and more friendly to the
environment. The most popular agents used by home brewers are listed in the
table above
Many home brewers use primarily bleach and iodophor. Both are relatively
inexpensive, and very easy to use. Many home brewers have tried some of the
powders, but find that they must be more meticulous with rinsing, so they
stopped.
The above table shows the recommended amount of each agent which should be
used, as well as how long items must be soaked in it to be considered sanitized.
Note that the first 3 each require one tablespoon of agent per gallon of water.
It is extremely important to note that you cannot reduce soak times by increasing
the concentration of the agent. It simply doesn't work that way. By increasing the
concentration, you are simply wasting your agent, and therefore your money. You
are also increasing the chances that rinsing won't get rid of all the agent.
Some agents like bleach not only sanitize, but they also clean to some degree.
Nonetheless, it is still a good practice to manually clean your equipment before
putting into the sanitizing solution, or use a cleaning solution from far above.
Bleach is known to be a fairly corrosive substance when in contact with most
metals, but it's fine to use as long as you don't exceed the concentration and
soak-time listed above. If you do not believe me, check with John Palmer. He's
a homebrewer and a metallurgist by profession. Plastics can be left in longer,
but note that most of the clear plastic siphoning tubes will become discolored
if left in a bleach solution for several hours.
Not many home brewers know this, but iodophor is also mildly corrosive to
metals. An E-friend of mine in Austria has a son who studies at the prestigious
Weihenstephen brewing university in Germany, and I have this information from
him. No breweries in Germany will use iodophor because of this. However, it's
significantly less corrosive than bleach, and we still use that in our kegs and
other metal parts of the brewery. Again, just make sure you don't exceed
the concentration or soak times.
Procedure
We usually maintain 2 buckets - one with an OxyClean solution for cleaning and
the other with an iodophor solution for sanitizing. Both get the lids tightly
sealed onto them when not in use. Equipment first gets soaked in the OxyClean
solution, then rinsed extremely well, and finally soaked in iodophor.
Whichever sanitizer you use, simply fill a bucket with water, and stir in the
proper amount of agent according to the above table. Then allow your equipment
to soak for the listed time. For longer pieces of equipment like racking canes
and plastic spoons, you can save yourself a lot of solution by soaking in a
plastic wallpapering trough instead of a bucket. This should require as little
as 10% of the amount of solution as used by a bucket.
After soaking, remove equipment from the solution, and rinse well under your hot
water faucet. Iodophor used to be the only sanitizing agent which need not be
rinsed off after soaking, but the new kid Star San falls into the category as
well. See below for details. With all other agents it is extremely important to
rinse well, otherwise the agent will make its way into your beer, and in the
best case produce off-flavors, while in the worst case it could completely ruin
your beer. We once messed up an otherwise very promising batch of beer by not
rinsing the keg properly after trying out a new sanitizing agent on it. This is
when we learned that B-Brite is a great sanitizer that is friendlier on the
environment than bleach, but it has to be far more carefully rinsed after
soaking in it.
If you are using iodophor, you absolutely should read the excellent article by
Robert Arguello.
As mentioned, Star San from Five Star Chemicals is the new Wunderkind of the
brewing industry. Not only does it only require a short contact of a few
seconds, but it can also be stored and remain effective for long periods of
time. So although the cost of the agent itself is at face-value expensive, the
fact that you can store it for a long time dramatically reduces the cost of the
agent. Store in an air-tight container, and dispose when the pH rises above 2.9.
Due to the extremely short contact time required for Star San, a popular way to
use it is in a spray bottle. For example the inside walls of a plastic
fermenting bucket get sprayed down, and after a few seconds the remaining
sanitizer gets poured into a bucket to reclaim it for further use. And since no
rinsing is required, the bucket can now be used immediately. For carboys simple
put a liter or two of solution into the carboy and slosh it around thoroughly
ensuring to get complete coverage. Then pour out the excess into a container to
reclaim for future use.
Cleaning and Sanitizing
Metals
For hard metals like stainless steel there is nothing like a bit of good
old-fashioned scrubbing with dish soap and water to clean it. For stubborn
grunge, or lazy people, soaking overnight in OxyClean or PBW will clean just
about anything.
For cleaning soft metals like copper, or aluminum it is not advisable to scrub
with anything abrasive since that can actually etch the metal very easily.
Simply use a soft sponge or washcloth, instead. In the case of aluminum brew
pots you do not want to scrub away the oxide layer which after the first use
prevents your wort from coming in contact with the aluminum.
Soaking metals in bleach is OK so long as you stay with minimum concentrations
and contact times. Any longer than this is a very bad idea as we learned the
hard way. We used to let our smaller pieces soak in our SS brewpot in a bleach
solution. When the pot one day sprung a leak, we had learned our lesson.
Cleaning and Sanitizing Plastic
Do not use abrasive materials on your plastic parts, since that will scratch the
plastic, thus giving bacteria a nice place to take up residence. Use a regular
dish-cloth or sponge with a bit of dish detergent. Again for stubborn grunge or
lazy people soaking overnight in OxyClean or PBW will clean just about anything
It is also advisable not to soak soft plastic racking hoses for extended periods
in chlorine. Even an overnight soak can cause the chlorine to react with the
hose to turn it extremely cloudy. Hard plastics do not suffer this fate. The
same type of clear vinyl hose soaked in iodophor for extended periods will take
on a red-orange tinge in color, but can still be used afterwards.
Re-Use
To economize, it is possible to store some sanitizing agents for use over
extended periods. Chlorine-based sanitizers are particularly useful in this
regard. Indeed, since they are so detrimental to the environment, if you do use
them, please consider storing a bucket of solution for continued use. As long as
you can smell chlorine in the bucket, it is still active. Since chlorine does
evaporate over time, you may have to add more agent from time to time. Any
re-used cleaner or sanitizer should be kept in a tightly sealed container both
to keep pets and children from drowning, as well as to keep the active
ingredients in the agent from evaporating away, as most of them can do. For
iodophor, when the color goes out of the solution, it is time to discard it and
make up some more. For Star San you discard when the pH goes above 2.9.
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