Re: Harvesting the Coopers Yeast Video
Keep re-using the cultured bottle yeast numerous times by doing a "yeast wash" to save the yeast in your fridge for future use. Some good picture posts if you Google it.
Summary: The purpose of yeast washing is to separate the healthy living yeast out while they are still mixed in suspension(cloudy water) and the heavier trub goop has settled out to the bottom.
1. After racking the beer add 2L of distilled water to the primary fermentation pail trub, swirl around to completely mix and pour it all into a clear glass jug.
2. Wait 20-30 minutes for the liquid to stratify(separate) into three layers: top layer is beer, middle milky layer is the yeast+water you want to collect, bottom is waste solids, hops, etc. that you do not want. If there is too much solid goop and not enough yeast+water mixture then pour/siphon to another jar leaving the solid goop behind and repeat this washing step.
3. Then use a turkey baster to siphon off the middle yeast+water milky layer and fill each beer bottle 100% full with liquid(no airspace), then cap airtight for long term storage. Beer bottles are safer and easier to fill airtight which theoretically stores yeast longer than mason jars. Your bottling anyway and already have extra sanitized beer bottles.
4. Store in the back of fridge, 1/4 inch of solid off-white colored yeast settle out after a day or two.
5. Before using warm a bottle to room temp(wort temp) and then pour off some of the top liquid, swirl around to mix up the compacted yeast and add directly to the wort, no starter is required.
6. Others state they have reused 5,10, 20 generations using good sanitization until the yeast mutates or dies. Each generation lasts in the fridge up to a year or until it turns brown, peanut butter color. Replace the yeast if it is not fermenting normally, is taking forever to start up, or if you get odd flavors.
7. Use the yeast and make a batch of beer is the 1st generation. The 2nd generation is created when you wash your 1st generation yeast and collect about six bottles of yeast. The 3rd generation is created when you wash the yeast from the last bottle of 2nd generation beer and collect 6 new bottles of yeast. Continue creating new 4th, 5th, etc. generations as needed assuming you brew with all those saved yeasts before they go bad as the yeast does not survive indefinitely. By harvesting the yeast again from each subsequent yearly batch you can keep a liquid live strain regenerating each year for say 5 generations = 5 years give or take the quality.
By Doug on
3/17/2010 3:08 PM