Using 6 month old yeast package?

[gregfreemyer]

I bought a Wyeast 3944 Belgium Wit package a while back. It was packaged at the end of September.

I ended up not using it (I poured my wort on an existing yeast cake). It's been in my fridge the whole time since then.

I want to brew a belgium wit this weekend and I'm wondering what I need to do special to use that 6-month old yeast package:

- pop the bag a day or so early and leave it at 70. The extra time will let the live yeast replace the dead.

- Make a starter a day or so ahead and let the yeast do it's thing

- Throw it away and buy a new bag.

Thanks
Greg

 

[JimRausch]

There are still live yeast in there, but definitely fewer than original(if you're interested, the 'Mr.Malty'site could give you an estimate of how many).
So, yes you will need to make a starter to build up the numbers. How much? Mr. Malty will tell you, depending on the projected OG of your brew. It'll probably take more than one day to grow it up to optimal numbers and may take a multi step starter or a large one. Can be done!

 

[weirdboy]

You'll want to make a starter. Ideally, you should step it up since you're probably down to around 20-25% viability on that package.

I don't know what you are doing for aeration on your starters. If you have a stir plate, a step from 0.5L to 1L will get you pretty close, and just repitching your 1L starter into another 1L starter (that is, crash your yeast, wash it, and pitch into a new 1L starter) should get you more than enough viable cells.

If you are shaking it occasionally, you'll want to go bigger if possible, but I would stay at 1L or less for the first step personally.

You can play around with the calculator here to see what you can do with your equipment:

http://yeastcalculator.com/


I would also note that when you are stepping up a starter, you'll generally want to plan ahead well in advance of brew day, as it takes time to crash/wash the yeast, and you will also want to be sure to let the yeast slowly acclimate to pitching temps for each step, including on brew day.



One other note about this:

You may look at how much you'd spend on DME (if that's what you're using for starters) to make all those starters, and the time investment, and then decide it's just not worth the effort involved compared to going out and buying a new package of 3944, which you could even combine with your old yeast package on brew day. I generally make my starter wort from AG, either using a bit of milled grain, or leftovers from a previous batch, so the cost of making a starter is almost nothing compared to buying a new vial/package of yeast. However, DME is rather pricey, so it's a closer trade-off in my opinion if you are using that for your starters.

 

[gregfreemyer]

Thanks,

This will be my first starter and I'll use the "occasional shake" method.

I found these instructions which is what I will pseudo follow:

http://www.howtobrew.com/section1/chapter6-5.html

That says to treat the smack pack as a 4 oz mini-starter, so I'm warming the pack now and will pop it when it gets to room temp.

Those instructions say nothing about crashing / washing. Do I have to do that?

If not, I interpret the (attached) Yeast Calculator data to say I can then transfer the Liquid Yeast Package to a 0.75 quart starter. And from there to a 1.5 quart starter and I only need 5 oz of DME total.

When do I add the DME? ie. 2 oz for the 0.75 quart and 3 oz for the 1.5 quart?

Or do I make up wort with no yeast from 1.5 quarts of water and 5 oz of DME, then add half of it as step one, give the yeast a day or two to grow, then add the other half of the wort.

BTW: I think dme is about $4/lb locally and I only need 5 oz I think. Not a great cost savings, but I'm intrigued to do my first starter regardless. Longer term I'd like to do bigger batches, so knowing how to use a starter to keep the cost of yeast down would be cool.

Greg

View attachment YeastCalc Yeast Calculator.pdf

 

[weirdboy]

I wouldn't worry too much about washing the yeast if it's your first time making a starter or working with yeast in this fashion. The only caveat there is that you will end up with a slurry that contains a lot of dead cells in it, in addition to your active cells. But you will still want to cold crash each step in the fridge for maybe 24 hours, and then carefully decant the clear liquid off the top, unless you are pitching into much larger containers.

If you don't have an Erlenmeyer flask, your process is going to be different from what I do. But you'll probably want to boil your starter wort for about 15 minutes and then let it cool to room temp before pitching for each step you do. I would create a starter wort of the desired size, put it in a suitable sanitized container, and then pitch the yeast onto that just like it's a mini batch of beer.

I work in metric when dealing with starters because the arithmetic is easier to do. 100g of DME per 1L of wort gives you about a 1.040 starter wort.

You should not create a 0.75 quart wort, and then adding another 0.75 quarts to make a step to 1.5 quarts. That is basically making two 0.75 quart starters. Instead, you should make a 0.75 starter wort, pitch, let that go for 24 hours or so, then cold crash, decant, and make another fresh 1.5 quart starter wort in a separate container, into which you pitch your yeast slurry.


Also don't forget that the DME occupies volume as well. If you add DME to 0.75 quart of water, you'll end up with something closer to 1 quart of wort. So, add the DME to a dry container, then add the water to the desired volume, then boil.

 

[flars]

Forget the "How To Brew" instructions. They are old and generic.
Try the Brewers Friend calculator. It is fairly easy to use.
http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

Complete the first step starter. Chill and decant the spent starter wort. Add fresh wort for step two to propagate more cells.

We can talk you through it if you give us the estimated OG of your beer, production date of the yeast, and volume you will have in the fermentor.

 

[gregfreemyer]

Forget the "How To Brew" instructions. They are old and generic.
Try the Brewers Friend calculator. It is fairly easy to use.
http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

Complete the first step starter. Chill and decant the spent starter wort. Add fresh wort for step two to propagate more cells.

We can talk you through it if you give us the estimated OG of your beer, production date of the yeast, and volume you will have in the fermentor.

I just popped the smash pack, so that is 4.25 oz per the package and fermentation has commenced inside the bag. I've put it up above my refrigerator for now. That's about 80 degrees, as recommended by something I read.

It was manufactured Sept 26, 2013

The OG for the beer is 1.051

I'm doing a 5 gallon batch going into the fermenter.

== issue #1
When I put my manufacturer date into:

http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

It says there is no viable yeast. The other 2 sites I tried said 24%. I guess I'll know by morning if the the smack pack has swelled any.

== current plan

I hope to pitch the final beer Saturday around 7pm, but I can hold off pitching a day or two if required. I'm brewing Saturday for sure, but I assume I can wait a day or two to pitch.

For tomorrow: I assume there is no way to decant the yeast out of the package, so tomorrow around noon I will make up 0.75 liters of wort, boil it to sanitize, cool to room temp and pour the package of yeast into it, then leave it at 70 to ferment.

Then Friday around noon I will put it in the fridge to cold crash for about 21 hours.

Saturday about 9am, I will decant off the clear liquid on top and discard. The "yeast cake" I will add to a 1.5 liter starter.

I will let that ferment at 70 degrees for about 9 hours, then use it to pitch into my freshly boiled and cooled wort.

I'm not used to pitching such a big volume of liquid. Do I need to adjust my water volumes to allow for that?

(I'm not sure exactly how much my carboy will hold. Maybe 5 1/4 gallons? If so, I may overflow it when I rack to secondary if I do a full 5 gallons + 1.5 liters of starter.)

Also, am I shooting for 1.051 OG before pitching, or after?

 

[weirdboy]

9 hours is a bit on the short side for the starter before pitching. I would give it 12 at a bare minimum, and personally would be more happy with ~16 or so. Ideally, you'd also cold crash and decant that before pitching as well, but you don't seem to have that much time unless you can brew on another day.

I wouldn't worry too much about adjusting the volumes over 1.5 quarts of starter. Also, you shouldn't need to secondary a witbier. They are ready to drink pretty fast usually anyway, but if you want to give it more time, just leave it in the primary longer. My typical process would be to let it ferment out and then let it sit there without touching it for another ~2-3 weeks before packaging.

 

[flars]

I usually start out a little more conservative with old yeast. The yeast is very weak. A full wort of 1.040 OG may be to much stress for the yeast. I would recommend beginning with a 1.015 OG wort. I do not adjust the volume of water used because the DME occupies volume. A 1 liter starter has the DME added to 1 liter of water.

Starting cell estimate 21 billion
0.75 liter 1.015 OG 1.1 oz DME 68 billion cells
1.5 liter 1.036 OG 5.4 oz DME 182 billion cells

This is about the minimum number of cells for a 1.051 OG beer. You could make a larger step 2 starter.
2.0 liter 1.036 OG 7.2 oz DME 203 billion cells

Begin step 1 as soon as the yeast pack begins to swell to save a little time. It will take time for the yeast to settle after fermentation complete. A completed starter can be refrigerated if it is completed early. You would also have time for step 3 if step 1 did not produce as many viable cells as anticipated.

The yeast pack has a nutrient pouch in it. Add some nutrient to your step 2 starter if you have it.

Are you fermenting in a bucket then planning to rack to a 5 gallon secondary for clearing? You could leave your wit in the primary and accomplish the same clearing.

 

[weirdboy]

I usually start out a little more conservative with old yeast. The yeast is very weak. A full wort of 1.040 OG may be to much stress for the yeast. .

Now, this is just my way of thinking about these things, so take it with a grain of salt:


Think of this 5 gallons x 1.050ish SG wort as containing 5 x 50 = 250 "gravity points" worth of sugar.

In an ideal fermentation scenario, we want ~200 billion healthy cells for 250 gravity points, or roughly 800 million healthy cells per point.

Going by standard degradation rates, we still have over 20 billion healthy yeast cells floating around in that packet.

In a 0.75 quart starter of 1.040 wort, we have 40 x 0.25 x 0.75 = 7.5 "gravity points" worth of sugars in that solution.

20 billion / 7.5 = 2.67 billion

So, we are pitching over three times the number of healthy cells needed to ferment that tiny starter.

 

[gregfreemyer]

I usually start out a little more conservative with old yeast. The yeast is very weak. A full wort of 1.040 OG may be to much stress for the yeast. I would recommend beginning with a 1.015 OG wort. I do not adjust the volume of water used because the DME occupies volume. A 1 liter starter has the DME added to 1 liter of water.

Starting cell estimate 21 billion
0.75 liter 1.015 OG 1.1 oz DME 68 billion cells
1.5 liter 1.036 OG 5.4 oz DME 182 billion cells

This is about the minimum number of cells for a 1.051 OG beer. You could make a larger step 2 starter.
2.0 liter 1.036 OG 7.2 oz DME 203 billion cells

Begin step 1 as soon as the yeast pack begins to swell to save a little time. It will take time for the yeast to settle after fermentation complete. A completed starter can be refrigerated if it is completed early. You would also have time for step 3 if step 1 did not produce as many viable cells as anticipated.

The yeast pack has a nutrient pouch in it. Add some nutrient to your step 2 starter if you have it.

Are you fermenting in a bucket then planning to rack to a 5 gallon secondary for clearing? You could leave your wit in the primary and accomplish the same clearing.

I followed your steps, but only gave step 2 9-hours to ferment before pitching.

The step-2 starter had almost a 1 inch krausen on it when I pitched, so the yeast was very active. I don't what that means as far as new cells propagating.

This morning (about 36-hours after pitching) I had a slight krausen overflow from my fermenter. I put 5 gallons into the fermenter (a 6.8 gallon bucket). I've done this recipe before and never had any overflow at all, but I raised the OG from 1.050 to 1.053.

So either the higher OG or healthier Yeast population caused a bigger krausen. I assume a bigger krausen is a good thing?

 

[flars]

Two reasons for heavy krausen. Very good pitch of healthy yeast or fermenting wort is much to warm.

I'm sure at this stage you know about having you fermenting wort within the ideal fermentation temperature range of the yeast being used.

Must be a good pitch of healthy yeast.