I am getting ready to go to Germany for a couple of weeks. Please discuss methods of harvesting and transporting yeast samples from the breweries I am likely to visit. In particular I am interested in what it would take for me to harvest and culture samples from my favorite Lager and Hefeweizen (both from are from Mahr's Brau in Bamberg. The Lager is their "Ungespundet" (non-filtered) beer, so I would think that a sample should be fairly easy to harvest from a bottle of either. However, if it would be practical to bring two or three more yeasts home I would certainly like to.

Thanks,
Jerry Scott


RESPONSE:

Jerry,

The best way to transport yeast is on slants of YM or wort agar. YM agar is commercially available from various producers like Oxoid, Difco, or Himedia. You can produce wort agar yourself by adding 1.5-2% agar to regular wort. The yeast can be isolated by putting the bottle in a fridge and let the yeast settle, than decant the beer and take a loop (or toothpick) full of yeast and inoculate the slants.

The problem is that you might have some trouble at customs if they find your yeast cultures. Therefore the easiest way to pass customs is to bring the beer itself in its original bottle and isolate the yeast at home. BUT this only works for the non-filtered lager beer. The Weizenbier will most likely have different yeast in the bottle than used for the main fermentation. Weizenbier producers tend to use lager yeasts for bottle conditioning because of their better flocculation properties.

If you visit the brewery you could also ask the brew master if he could give you a little sample of his yeast. If you mention that it is for home brewing and not for commercial application I am sure he will give you some yeast slurry. You should keep these samples refrigerated as much/long as possible and you should be able to keep the yeast alive until you are home. There you can cultivate the yeast on slants or plates. But customs might be a problem again for this option.

Tobias