Yeast----1 gallon vs 5 gallon batches

Sorry if this has been posted before but I haven’t been able to find it.
Any 1 gallon kit that NB sells calls for a 1/2 package of yeast to be used in a 1 gallon batch. Yet, only a full package of yeast will do the trick for a 5 gallon brew. Why do you need 1/2 the amount of yeast to service a wort 1/5 of the size?It seems that you should be able to get away with a lot less yeast in the smaller batch.

IMO 1/2 is a lot but if your not brewing anything other then one, one gal batch its ok. some will say its overkill. Myself ,I will do four allgrain, one gal batches, each with different dry hops additions and fermentation temps when I’m experimenting. then I make a 24 0z starter with one dry yeast packet , let it run 6-8 hours , split it up 4 ways , pitch them in the one gallon jugs. I never had a problem with to little or to much yeast. The one thing that 1/2 packet of yeast will do for sure is shorten your fermentation time. it may finish faster and have a different taste then if you use 1/5. Its better to over pitch then under pitch. good luck dwhahb.

Many thanks for your quick reply. Besides wasting the yeast, I was afraid of a major blow-off.

I was thinking also of using a yeast starter and dividing it 3 or 4 ways. You say you use dry yeast. Would the same hold true using Wyeast liquid packets?

Starters are typically not done with dry yeasts. They’re generally cheap enough that buying extra packs is worth the time and DME savings. There are other very technical reasons that dry-yeast starters aren’t recommended, but honestly the microbiology is kinda beyond me.

For dry yeasts, 1 pack generally gets the job done for most beers, but for liquid yeasts one pack/vial is usually considered under pitching, that’s where starters come in.

I would bet they recommend 1/2 pack because over pitching is better than under pitching and they’re erring on the side of making better beer.

using Wyeast liquid packets, it is common to do a starter when doing a five gal batch. I would say its necessary, but to me cus I’m so cheap, I would not waste the money on that for small batches or experiments. on the other hand ,yes you could split one that way, but you need to let the starter go a lot longer because there are fewer cells in them I believe.
the thing about Wyeast liquid packets , the yeast are in mush better shape then the dry stuff, and you can expect better results from starters. by better I mean healthy and vigorous .
this is about the limits of my knowledge since I have not done 1 gal splits with weast , just the dry yeast.
oh ya ,with using starters on dry yeast, I feel the lag time is less and less lag time is always good. on top of that you can make sure the yeast are good when you do a starter. Win win to me.

I’ve not seen a significant difference in lag time between my liquid yeast starters, and my re-hydrated dry yeasts. My rehydration procedure is to put the dry yeast on my stir plate with 1/2 - 3/4 cup water that had been boiled and cooled to under 85F; 5-10 minutes spinning max, then into the pool. I only use the stir plate because I made it myself and feel cheated if I don’t get to play with it.

I usually can detect activity starting by bedtime on brew day, with more vigorous activity by morning.

I still wouldn’t recommend a dry-yeast starter, but whatever makes tasty beer for you is fine by me. :cheers:

[quote=“Jasperjuice”]Sorry if this has been posted before but I haven’t been able to find it.
Any 1 gallon kit that NB sells calls for a 1/2 package of yeast to be used in a 1 gallon batch. Yet, only a full package of yeast will do the trick for a 5 gallon brew. Why do you need 1/2 the amount of yeast to service a wort 1/5 of the size?It seems that you should be able to get away with a lot less yeast in the smaller batch.[/quote]

Some dry yeasts come in smaller packs and half of one of those would be less of an “over pitch.”
A lot of brewers look down on Munton’s regular yeast, but I just brewed a fantastic mild ale with it. I was also happy with a bitter brewed with it.

I use partial packs of yeast for all my small batches. For example, for a 1.67 gallon batch, I will use 1.67/5 = 1/3 of one packet. If dry yeast, I just sprinkle it in. If liquid yeast, I usually make a starter, or else I pitch more, like 2/3 pack or a full pack of yeast.

Hi guys, been a while since I’ve been on here. Was in a small place for the summer and not enough space for brewing (sob). I have about 5 weeks before I have to move again, but am dying to brew. I have one packet of Safeale K97 dry yeast that has been kicking around for 8 months mostly in but sometimes out of refrigeration. I want to brew 2 one gallon batches with my yeast and split it between the two. Am hoping for a twice as fast fermentation time so I will have time to bottle and condition before moving again on 11/7. Sound doable? Thanks

Nope. K-97 is one of the slowest yeasts in existence.

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Ah thank you! May just have to wait for the next stop👍

hey glad you checked back in. I think trying to force a fermentation by an over pitch does’nt change much. You mite try pitching on the higher temperature range, depends what your trying to make