Cold Pitching Yeast

    If you harvest and reuse yeast from your fermenter, you should try cold pitching. This is done by pitching the yeast directly from refrigerated storage, into wort that has been cooled to about 4-5 degrees below the optimal temperature for the yeast strain and beer style. Cold pitching can give you shorter lag times, more vigorous fermentation and more complete attenuation.

     When harvesting yeast from the fermenter, leave a small amount of beer behind, then swirl to re-suspend the yeast in the liquid, and carefully pour into a sanitized growler or other glass vessel. Cap and place into the fridge. You want to keep the yeast at about 34° F. Cold enough to virtually stop autolysis (when the enzymes in dead cells begin breaking down the cell structure), but not cold enough to freeze.

     When pitching, some elect to pour off most of the beer, leaving only enough to rouse the yeast, others pitch the whole works. The yeast quickly warm up to the wort temp, and start taking in oxygen and nutrients, so be sure to oxygenate as well as you can. The activity from the respiration phase and beginning fermentation will raise the wort the remaining few degrees to your optimum temp.

     Don't have harvested yeast? You can also use cold pitching with a starter. Grow it up as usual, allowing an extra day or two for refrigeration and settling.

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