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The low-cost QC challenge
Material for this story comes in part from a talk
by Lisa White, vice president of White Labs, at the Craft Brewers
Conference in April 2005.
Brewers have many challenges when it comes to
fighting unwanted bacteria such as Lactobacillus and Pediococcus, but
the battle can be won on a limited budget and with limited manpower. How
can you fight contamination and keep it simple at the same time? Here
are a few general tips before we talk about the specifics of a QC
program.
* Learn testing basics through classes or seminars at
the various brewing conferences. On a more advanced level, training is
available through Siebel Institute of Technology’s two-week
microbiology course for brewers. White Labs also offers on-site
consulting for brewing emergencies or scheduled events. Some
establishments have White Labs come to their breweries on a regular
schedule, such as once a year, to check QC procedures and offer
practical advice.
* Develop a habit of using down time to test. Soon
this will be as much a part of your routine as cleaning and mashing in.
* Use a flame and Isopropanol when possible.
The essentials for good testing practices are fairly
inexpensive. You will need the following items:
Isopropanol, a cleaning agent that can be found in
most drug stores; a flame source; sterile water; sterile pipets, tubes
and bottles; and microwaveable media. For those with larger budgets,
consider purchasing an autoclave. At White Labs, we autoclave almost
everything, including media and bottles. Another solution for those with
limited budgets is a pressure cooker, which many brewers use. These can
be found in kitchen supply stories or on Web auction sites for less than
a couple hundred dollars. At White Labs, we also sell new ones.
Now that you have some general tips and equipment
knowledge, let’s move on to some of the tests that you can perform.
Here are a couple good ideas:
* Forced wort test. This test measures the cleanliness
of the wort chiller and hard pipe or hosing leading up to the fermentor,
before the yeast is added. Obtain wort sample and place into a
sterilized container. Incubate in a warm area for a few days (optimal
temperature is 30 degrees Celcius. After three days, if it is clear,
your brewery is safe. If it is cloudy or bubbles appear, you may have
problems in your brewery.
* Environmental tests: To test the air, leave a plate
out in the brewery for an hour and examine it with your eyes (no
microscope necessary). If something appears on the plate, your air is
not as clean as it needs to be. With training, you can learn to detect
what kind of problem you have by just looking at these plates.
These are just a few easy tests that you can perform. In future
issues we will look at other tests and techniques that you can use to
keep your brewery safe and your beer tasting great. |