Yeast starter with dry yeast

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

jemmy818

Member
Joined
Jul 17, 2013
Messages
6
Reaction score
0
I am brewing Bavarian Dunkel with saflager w 34/70 yeast. Can I do a yeast starter and stir plate the same way with liquid yeast? I just wondering if there were any thoughts on this.
 
For a lager, I'd just rehydrate and pitch two packs. No starter.

If you just have one pack, rehydrate it first before pitching into the starter wort. That helps you begin with more live cells in the wort. Aerate the heck out of the starter wort before pitching (either with O2 or by putting it in a big sanitized jar and shaking it vigorously a few times).
 
Dried yeast were packaged at a specific stage in their life cycle to ensure they wake up with full energy reserves ready to multiply and eat sugar. By making a starter you get more yeast, but you may not pitch them at their optimum vitality.
BigFloyd has given the current best practice: rehydrate 2 packs and pitch.
 
Dried yeast were packaged at a specific stage in their life cycle to ensure they wake up with full energy reserves ready to multiply and eat sugar. By making a starter you get more yeast, but you may not pitch them at their optimum vitality.
BigFloyd has given the current best practice: rehydrate 2 packs and pitch.

Even worse, by pitching dry yeast straight into wort (even starter wort), you kill up to 1/2 the cells before they have a chance to reproduce. You then have to work to build the cell count back up just to get to where you began.

This has to do with the dry yeast needing to rebuild their protective cell walls. The rebuilding takes about 15-20 minutes and happens best in warm (95-105*F), sterilized (by boiling) tap water (not distilled).
 
Another thing to remember is that with dry yeast you do not need to aerate the wort.
 
You can make a starter from a pack of dry yeast. Just rehydrate before pitching the yeast into the starter. I did this about a month ago as I had a dry yeast pack that was close to the 2 year mark and didnt realize it until about 48 hours before I was going to brew. I had starter activity within about 2 hrs. About a 3 hour lag after pitching the starter into the wort.
 
Another thing to remember is that with dry yeast you do not need to aerate the wort.

True. I always oxygenate (with O2) when using liquid yeast, but not if I'm simply rehydrating and pitching dry yeast.
 
The packaging should specify, but if it doesn't: place the yeast in a few ounces of warm (90) degree water about 15 min prior to pitching. Some people add yeast nutrient or a tiny bit of sugar. You just have to be careful that there isn't too much dissolved in the water otherwise it stresses the yeast.
 
Any recommendations on how to rehydrate the yeast?

Rehydrate using these steps (for an 11g pack):

1) When you are about to start your boil, put 1 cup water (not distilled) in a Pyrex cup in the microwave. Boil it for about 6 minutes down to about 1/2 cup.

2) Cover the cup with a piece of sanitized foil (sprayed with Star-San). Set it aside to cool to about 95-100*F.

3) Once the water has cooled, sanitize the yeast packet and cut open with sanitized scissors.

4) Sprinkle it on the water (do not stir yet), cover and let sit 15 minutes.

5) Stir well, cover, and let sit 5 more minutes.

6) Hopefully by now, you have your wort chilled (about 62-64*F for a typical ale) and ready for the yeast.

7) The yeast slurry needs to be "attemperated" before you pitch it in the wort. That means you have to add small amounts of the cooler wort into the yeast slurry, stir and let it sit a few minutes. You'll probably have to do this a few times to get it to within 10*F of the wort temperature. Once it's within 10*F, pitch away.

Dry yeast has its own nutrients. I would not add sugar, yeast nutrients or anything else to the tap water.
 
Or don't rehydrate and just pitch dry... the net result is the same. While it is true that rehydration gives you more viable cells, the cells that don't survive when pitched dry become nutrients for the remaining cells. I have experimented with this at this at the commercial level and came to the conclusion that there is no noticeable difference in the end product. I always pitch dry, adding my yeast to the fermenter before adding wort, and I have active signs of fermentation in 8 hours or less consistently. By rehydrating you are adding steps and potential avenues of contamination, it really isn't worth it in my opinion.

Here is a vid someone made with a basic experiment:
 
Last edited by a moderator:
Rehydrate using these steps ... The yeast slurry needs to be "attemperated" before you pitch it in the wort. That means you have to add small amounts of the cooler wort into the yeast slurry, stir and let it sit a few minutes. You'll probably have to do this a few times to get it to within 10*F of the wort temperature. Once it's within 10*F, pitch away...

I've never before heard of this "attemperation" step for dry yeast -- is this to prevent temperature shock at pitching? Why would it be different for dry versus liquid yeast, especially if it's to combat temp shock?

A quick google search pulls up some results of a 2000 interview with Clayton Cone at Lallemand discussing attemperation, and a few posts from yourself here on HBT discussing it. It's an interesting idea, though I'm unsure as to why you would go through the trouble versus simply letting the rehydrated yeast cool to within 15f of pitching temp (which in many cases would be room temp, or slightly below.
 
It's an interesting idea, though I'm unsure as to why you would go through the trouble versus simply letting the rehydrated yeast cool to within 15f of pitching temp (which in many cases would be room temp, or slightly below.

Because it takes longer just sitting on the counter for it to cool down to within 10*F of wort temp than the amount of time that you should allow the yeast to simply sit around after being rehydrated.

Room temp here right now is 75*F. That's too warm to pitch. I'm typically pitching with my ale wort at around 62*F and letting it come up to 63-64*F to start fermenting. The only way to get the rehydrated yeast slurry within 10*F of that is to attemperate it. It takes just a little bit of time and is extremely easy to do.
 
Back
Top