For Better Beer, Make a Yeast Starter

Are You Pitching Enough Yeast?

Maybe.  Professional brewers use certain pitch rates for styles and different strains.  Let’s get the geeky calculation out of the way.  For an ale, brewers use 0.75 million yeast cells per milliliter per degree Plato.  A five gallon batch has roughly 20,000 milliliter of wort. What’s a Plato?  Oddly brewers tend to use a different gravity measurement than homebrewers.  To convert, drop the 1.0 and divide by 4.  ie. Change 1.048 OG to 48 then divide by 4.  1.048 SG = 12 Plato.  Running the math and remembering all those zeros, a 1.048 wort needs 180 Billion cells for ales.  For Lagers, we need twice as much.  A 1.048 SG needs 360 Billion Cells.

So How Many Cells are You Pitching?

A dry yeast pack typically has 160 Billion cells and WYEAST and White Labs typically have 100 Billion cells. Viability (the percentage that are alive) goes down over time, much faster with liquid.  If you are making 5% ales and pitching 1 pack of dry, you are doing well.  If you are using one pack of liquid, you are likely under-pitching.  You are likely making very good beer no matter what, but we want you to make even better beer, on a budget.

Make a Starter!

A starter is simple.  You can grow your liquid yeast up to the desired pitch quantity.  We use Mr. Malty to make an estimate  You will need a 2 or 5 liter flask, 5 Star Dr-Foamer, Briess Dry Malt Extract (DME), Yeast Nutrient and Aluminum Foil.  We carry everything you need.  Making a starter is simply making a small batch of beer and letting the yeast multiply before pitching into the wort. Use DME that closely represents your style or make sure you decant the yeast.  We will go over that later.

The goal is to make a 1.040 wort.  Mix 1 cup of DME with 1 liter of water, add a drop of de-foamer and a tiny pinch of nutrient.  Boil the flask directly on the stove for 10 minutes and let cool. Watch out for boil overs, they’re sticky.  Add your yeast after it cools below 80.  Put sanitized foil on top.  No need for a stopper, we want oxygen.  Don’t use a foam cap common on internet retailers.  Foam is a pain to sanitize.  Agitate the starter by hand frequently for about 24 hours and pitch.

According to Mr. Malty, if we are planning a 1.048 wort, we need a 1 liter starter and 1 WYEAST Smack pack.  If you are doing bigger beers often, you may want to consider a stir plate.  Stir plates constantly agitate and produce more yeast cells.

If your starter is large or you feel it will dilute and effect your beer, decant it.  Let it stand in a cool place and the yeast will settle to the bottom.  Decant the “beer” off the top and pitch.

Dry Yeast Starter?

We do not recommend dry yeast starters, though they do work. Dry yeast is dehydrated with maximum energy stores.  They are ready to go and a starter will deplete these stores.  Dry yeast is also generally cheap enough that a starter is only minimally cost effective. For big beers and lagers, pitch two dry yeast packs.

What Happens When I Under-Pitch?

The less yeast you pitch, the longer the Reproductive Phase of Fermentation. This is the phase that produces the most flavors and aromas, some of which may not be desirable.  Of course, for certain styles, this may be your goal and you will need to experiment.  For bigger beers and lagers, they may not finish fermenting the wort.

All of our staff are ready to help you learn to make a starter and make great beer.   It sounds intimidating but it is incredibly simple and a great skill to add to your hobby.

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