Making Starter vs fermenting - what's the difference?

[Want2brew]

I get confused about how a yeast starter works vs a ferment. If I want to grow some yeast to do a larger ferment, I guess I start out making a starter.

If I take a quart of water and add 1/2 cup sugar and then add a packet of yeast, why would this produce yeast vs turning the sugar into alcohol?

What are good amounts of water and sugar to add to make a starter?
how fast can the yeast multiply and does more sugar need to be added at intervals to "feed" the yeast?
-If a cup of sugar is used, will it make an equal amount of yeast or how can I determine how much yeast is produced?

[rad14701]

I use 1 tbsp of sugar in 2 - 3 cups of 115F water for my starters regardless of how much yeast I'm pitching... 1 cup of sugar per quart is WAY too high gravity for a starter...

[rgreen2002]

+1 rad

A starter is just that... a head start for your yeast. It is a micro-environment where the yeast get ready to be part of the bigger picture... your mash/wash. There are several reasons to make a starter. Yeast starters help accelerate fermentation. With a fast start to your fermentation bacteria are prevented from taking over reducing the chance of an infected batch. Starters allow yeast to multiply which helps achieve a lower final gravity and avoid stuck fermentations. Multiplication of yeast is helpful in larger batches as the higher number causes less stress to the yeast. Less stress means less off flavors. You don't always need a starter and that can be a matter of preference in some cases (I don't use starter when I make rum).

When making a starter the recommendation is to aim for a SG around 1.040. This provides enough sugar for cell proliferation without causing the colony to become stressed. Technically you will produce alcohol but not at a substantial quantity to notice(you usually use a small volume for starters and I decant a lot of the excess liquid off myself before pitching...YMMV). The presence of excess oxygen will keep the cells reproducing until the sugar is depleted.

The other benefit of making a yeast starter is decreased cost. I use a white labs liquid bourbon yeast. The damn vial costs $7 and is good for 5 gallons. I'm making up to 30 gallons so I need more... on top of that I want to save some of the yeast for another day. Keeping some of the yeast from the starter keeps it viable and healthy. Taking the yeast after it has run through the mash is also a possibility but if those yeast were stressed during their stay in your fermenter then you have "inherited" that stress for your next batch.

Here is a good video from white labs that will give you some info... https://www.youtube.com/watch?v=1zUYxb- ... e=youtu.be" onclick="window.open(this.href);return false;" rel="nofollow and their website has useful info: http://www.whitelabs.com/resources/home ... arter-tips" onclick="window.open(this.href);return false;" rel="nofollow

Finally if you are going to make a starter I would get a stir plate. It isn't exactly necessary but it is quite useful and it's not too hard to make one(mine took bout an hour and cost about $20). There are about a million youtube vids on how to out there. It helps keep the oxygen content high during multiplication without you around to shake/stir.

After starters...you can move to yeast slants.....

[MitchyBourbon]

I get confused about how a yeast starter works vs a ferment. If I want to grow some yeast to do a larger ferment, I guess I start out making a starter.

If I take a quart of water and add 1/2 cup sugar and then add a packet of yeast, why would this produce yeast vs turning the sugar into alcohol?

What are good amounts of water and sugar to add to make a starter?
how fast can the yeast multiply and does more sugar need to be added at intervals to "feed" the yeast?
-If a cup of sugar is used, will it make an equal amount of yeast or how can I determine how much yeast is produced?

First, as rad pointed out, a starter should be made with a low gravity say 1.03.

Second, you need to add oxygen. If you don't add oxygen, the yeast will reproduce for only as long as there is oxygen in the wort. As soon as that is used up they will stop/slow reproduction and then they will begin producing alcohol. So if you want to make more healthy yeast you need to continually add oxygen. You do this manually by aerating the starter periodically. A stir plate works much better.

I use a stir plate and I like to start my starter 2 days before I intend to pitch it. I start with 1 liter sterilized tap at room temp. Add my yeast and let it rest 30 min. Then stir. Next I add 3 Oz of LME. I place my stir plate and starter in my lab (spare bedroom ) and I close the vent and block the fresh air return. I also do not cap the container for my starter. After the first day, I let turn off my stir plate for an hour or two and let the yeast settle and decant off all the liquid. Then I add 2 liters water and 6 Oz LME and turn on the stir plate again. After the second day I decant again and then I'm ready to pitch... batter up!

[rgreen2002]

Then I add 2 liters water and 6 Oz LME and turn on the stir plate again. After the second day I decant again and then I'm ready to pitch... batter up!

MB I've taken a lot of my yeast info from you and was wondering why the second run of LME? Is this to increase the colony #'s further, or condition for the pitch, or something else?

Also....I need a lab.

[3d0g]

Your starter medium should be similar to the target fermentables as well. A starter fed on pure sugar may be reluctant to switch to maltose / maltotriose.

[FreeMountainHermit]

Your starter medium should be similar to the target fermentables as well

As in using a sample of your intended wash for the starter environment ?

Seem to recall reading that here somewhere.

[der wo]

Your starter medium should be similar to the target fermentables as well. A starter fed on pure sugar may be reluctant to switch to maltose / maltotriose.

I often wonder, why it needs always time after pitching the starter into the mash, until the mash starts off. Sometimes more sometimes less. I have the feeling, it's much about different pHs.

[rad14701]

Your starter medium should be similar to the target fermentables as well. A starter fed on pure sugar may be reluctant to switch to maltose / maltotriose.

I often wonder, why it needs always time after pitching the starter into the mash, until the mash starts off. Sometimes more sometimes less. I have the feeling, it's much about different pHs.

A little bit of everything... pH, temperature, osmotic stress, etc, are all factors... My lag times are rarely longer than 15 - 30 minutes before I see activity when using a starter...

[der wo]

My lag times are much longer often. But it's no problem. Sometimes I will find out, if I can make it start faster by changing one of the little details...

[MitchyBourbon]

Then I add 2 liters water and 6 Oz LME and turn on the stir plate again. After the second day I decant again and then I'm ready to pitch... batter up!

MB I've taken a lot of my yeast info from you and was wondering why the second run of LME? Is this to increase the colony #'s further, or condition for the pitch, or something else?

Also....I need a lab.

That's a good question. The answer is that I don't always do this. Sometimes I only make a one liter starter that I add just 3 Oz of LME. Sometimes i don't even make a starter. So what could possibly be going on here. I mean a pack of yeast without a starter is supposed to work just fine right?

Maybe... I did it on a dare.

The truth is I am adjusting my pitch rate based on how much flavor influence I want from my yeast. My one liter starter multiplies the size of the yeast colony 4x and the 2 liter 10x (guesstimate). So if I want a lot of influence from the yeast I won't make a starter, I just rehydrate the yeast packet, aerate the wort well and pitch. If I want to minimize any flavor from the yeast I will make a 2 liter starter, decant the liquid off, skip the aeration step and pitch just the thick yeast cake. Notice that I don't aerate when I make a big starter. Also, I allow the starter to settle and then decant as much liquid off as I can. That liquid contains a lot of the precursors that might otherwise contribute various flavor components.

Bottom line... there are lots of things we can do with the yeast we use. There is no one right way. We should think about what we want out of the yeast and treat it accordingly. Currently, I am working out how I can make them grant me 3 wishes.

I think the Byrds said it best...

Ferment everything (turn, turn, turn)
There is a reason (turn, turn, turn)
And a time to every bourbon, under heaven…

[Kegg_jam]

I make starters for yeast that I paid a little more money for. Sometimes after a long break and if the yeast is of unknown quality.

But mainly I use DADY and it is pretty cheap so I'll just do the direct pitch method. Probably over pitch because I don't really measure anymore.

[rgreen2002]

Ferment everything (turn, turn, turn)
There is a reason (turn, turn, turn)
And a time to every bourbon, under heaven…

This.....is.....classic!

I get ya. I never really thought of throwing in a second run of DME/LME but I may want to double my colony #'s depending on the flavor of this current run. Gracias.

KJ - I'm with you on cost.... For $7 a vial that bourbon yeast is going to have to do some work! With Mitchy's idea I may double it next time and pull even more off to save for later dates.