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Letter from the President:
Visits to Europe and Asia

By Chris White

Recent visits to breweries in Singapore and Korea remind me how global our business has become. But it also demonstrated to me that brewers everywhere have similar questions regarding yeast and fermentation issues.

During a talk to Korean brewers, I was asked whether it was acceptable to buy our homebrew vials and grow up the yeast for larger volumes of beer.

This is a question I hear occasionally when I talk to professional brewers, especially in foreign countries where shipping costs may be higher. The answer may be instructive to a lot of our readers. The bottom line is, growing up the yeast can work under certain conditions, but it does invite a host of possible problems. It takes a long time to grow yeast from a small amount of yeast to a large volume. For us, it takes three weeks to grow yeast up from slants (part of this process involves quality control testing in the laboratory before, during and after the growth process).

When growing up yeast, brewers can unintentionally introduce bacteria into the picture (when it leaves our laboratory, the yeast is certified 100 percent free of bacteria). This is because when you have large volumes of yeast, you have billions of cells that can fight off contamination. When growing up the yeast, you have far fewer "soldiers" to fight off these intruders.

If you are culturing up from a slant or a vial, brewers will need an autoclave or pressure cooker to sterilize the equipment. After the growth process you will need to plate it on sterilized media to make sure you have not introduced any contamination. Most small brewers do not have the time, interest, or training in these tasks. In my opinion, your time is better spent on the final product and making sure the beer that you release is the of the highest quality. By the way, after my talk in Korea, another brewer came up to me and said the guy who grows up his yeast from vials has contamination problems.

You may be interested in learning a little more about my visit to Korea, which has a growing beer culture and more than 100 microbreweries. Most of these brewers were trained by Germans and every place I visited featured three beers: pilsners, dunkles and weizens. They were all unfiltered (one brewer told me they kept their beers unfiltered because this distinguished them from mass produced beers).

The brewers are a close group who are aiming to make better beer available to their peers. I expect to hear of great progress from these breweries in the years to come.

Chris White is President of White Labs Inc. and is a chemistry and biochemistry lecturer at the University of California, San Diego. He has a Ph.D in biochemistry. Feel free to write him about this column.