Article

Get Your Yeast Straight From The Bottle

It’s the homebrewer’s lament. We come up with what we think is the perfect “clone” recipe for Guinness, Sierra Nevada, Anchor Steam. We labor our nasal glands with the aroma of the hops and try to define the exact malts used until our tongue becomes a piece of useless flesh. Still the final product of our intense study and labor fails to meet our exacting demands.

What could possibly be wrong? Often we have the same grain bill as used in our favorite beers due to well-honed senses and intense study of available literature. The problem is that yeast plays much more of a role in the finished product than many of us realize.

There are homebrews made with everything from bread yeast to Duvel yeast cultured off of a hanky from the brewery in Belgium (true story). Not all are good, but not all are bad. The whole idea is to match the recipe with the yeast. You could make the perfect Sierra Nevada clone but if you use the Duvel yeast, you’re in for a big disappointment.

The point is, if you want to make a specific beer or get a specific distinct flavor characteristic, why not go to the source? You may be able to culture the yeast from a bottle of your favorite beer. The hard part is that not too many large breweries leave yeast in the bottle these days. It has become standard to filter the yeast and pasteurize the beer before packaging.

Fortunately, not all breweries filter (small microbreweries that only distribute locally are the most likely to leave the yeast in the bottle) and culturing yeast from the bottle is a simple procedure. It requires very little equipment and can be quite rewarding.

Hot Prospects

First, you have to find yeast in a bottle — not easy in this day and age. Look for the sludge at the bottom of the bottle. It looks similar to the bottom of your bottle-conditioned homebrew. Hefe-weizens, if they are true hefes (with yeast), will contain yeast but are often bottled with lager yeast for priming, which is different from the yeast used to ferment.

While this is often true, it is not always true, so culturing from hefe-weizens is still definitely worth a try. Sierra Nevada, Chimay, and most Belgians also contain yeast. Using the yeast from lambics is not recommended; the yeast strains are introduced at different stages of fermentation and often naturally (with wild yeast). You cannot culture yeast from any major brand such as Budweiser or Miller.

Your best bet is to look for yeast in the bottom of the bottles of beer from your favorite local microbreweries. Many microbreweries don’t filter and, being local, the beer (and its yeast) should be fresh.

If you can’t find yeast in the bottom of the bottle of a beer you are dying to clone, don’t fret. Many yeasts used commercially are available to homebrewers via Wyeast, Yeast Lab, White Labs, and other companies. These yeasts can also be cultured at home without hassle. Culturing these yeasts and repropagating them can provide many brews with just one yeast purchase. Often brewpubs or breweries will tell you what strain they are using for any given beer.

Culturing Bottled Yeast


Here is a simple method for yeast propagation and storage. This basic method is generally used to collect yeast for one brew, but the results may be stored for your own personal yeast bank for many future libations.

The advantage of this method is that it’s simple and doesn’t involve things like innoculating loops and petri dishes. The disadvantage is it doesn’t isolate the yeast strain. If there’s anything unwanted growing in the bottle, you’ll propagate that, too. The key is to culture the yeast as soon as you open the bottle. Don’t give bacteria time to grow.

Equipment list:

  • 12-ounce beer bottle
  • Bottle cap
  • Stopper to fit bottle
  • Airlock
  • Butane lighter or propane torch
  • Can of Lysol or store-brand disinfectant
  • Sanitizing bleach solution
  • One-quart mason jar or larger non-heat-sensitive glass container
  • Cellophane
  • Rubber band


Method:

Step 1: If you come across that ever-so-hard-to-find bottle with a wisp of yeast floating on the bottom, consider yourself blessed. You may want to say a prayer.

Step 2: Boil about seven ounces of wort with an original gravity of 1.030 to 1.050. Add four or five hop pellets for their preservative value to inhibit bacterial growth. Boil 15 to 20 minutes. Strain out hops and return to boil for 10 minutes.

Step 3: Pour the boiling wort into a sanitized beer bottle, cap with a sanitized cap, and cool overnight or until pitching temperature is between 58° and 65° F.

Step 4: Wipe countertop with a mild bleach solution. Spray the room with disinfectant 15 to 30 minutes prior to work period.

Step 5: Pop the top off the bottle-conditioned beer and pour all but the last inch and a half into a serving vessel to enjoy.

Step 6: Torch the top of the bottle containing the yeast very briefly with the lighter or torch.

Step 7: Carefully open the previously prepared wort and, with a cotton swab dipped in vodka (or isopropyl or grain alcohol), swab the bottle opening.

Step 8: Pour yeast into the wort.
Step 9: Reclean the bottle top with alcohol or vodka, seal it with a stopper and airlock, and allow it to ferment at room temperature.

Step 10: After fermentation is complete, the bottle may be capped with a sanitized bottle cap and saved in the refrigerator for later stepping up and use. The yeast can generally be stored for two to six weeks without further propagation. To propagate again use this same technique, taking a sample from the first propagation.

Stepping Up

After you have prepared the initial culture you will need to step it up for use. This can be done at a later date or at the initial floccu­lation time. A one-pint to one-quart yeast starter is the recommended pitching rate for a five-gallon batch.

Step 1: Wipe down countertop and spray room with disinfectant.

Step 2: Boil approximately
20 ounces of wort, 1.030 to 1.050 original gravity, and pour into a sanitized, non-shatterable glass container such as a mason jar.

Step 3: Cover with cellophane (attach to jar with a rubber band) and allow to cool to pitching
temperature.

Step 4: Remove bottle cap or airlock from previous culture, torch the bottle top briefly, and pour into the cooled wort.

Step 5: Re-cover the container with cellophane (or airlock for growler), and allow to ferment.

Step 6: Pitch starter to five-gallon batch as fermentation starts to subside (flocculation period).

All of these techniques for increasing the culture can also be applied to commercial yeast or yeast from brewpubs. To use commercial yeast simply prepare the initial wort as described but increase the amount tenfold. The packet or vial is then pitched into the wort, fer­mented, and capped for storage.

Thinking Ahead

You can keep a store of sterile wort for propagation or starters by boiling wort and canning it in one-quart mason jars. You know that the canned wort is clean, cooled, and ready for use should the perfect yeast-in-the-bottom bottle come your way. To can wort use the water bath method: Boil the filled jars for 45 minutes, remove from water, and cool. You know that the jar is sealed if the center of the lid indents. A pressure cooker will also do the trick. Refer to your favorite cookbook for canning methods.

Have fun and be sure to drink your work with pride.

Issue: May 1998