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Aggie4You
11-11-2004, 10:22 PM
I've been thinking about the different meads I've put together so far and I I came up with a few observations/queries that I thought I'd throw out there based on the sizing of a batch.

I'm sure we'd all like to be able to make super huge batches and still be able to work with them, but that isn't always practical. It seems that the most common sizes for homebrewing are 1, 3, and 5 gallons with a fair number of 6-7 gallon batches being created.

I was wondering if anyone had noticed a time differential in any of the different stages of the process (fermentation, clearing, aging) based on the size of the batch. Specifically, do you find that a mead clears faster in a smaller container? In my case, it would because I can put the smaller container (1 gallon) in my refrigerator while my larger container (5 gallon) wouldn't fit. Also, do you find that there is generally more lees, less lees, or about the same depending on the size of the batch (per volume). How about loss during racking (more, less, about the same)?

It also seems reasonable to me to expect a smaller batch to ferment (slightly) faster. Here's my thought process on this issue. Generally, when I make a batch (1 or 5 gallon), I start with a single packet of yeast. The yeast then multiply until all of the nutrients/oxygen are used up. Then, they begin the process of creating goodness. A single packet of yeast should exhaust the nutrients/oxygen in a small batch considerably faster than a large batch (probably not a linear curve though... a one gallon might go finish this stage twice as fast as a 5 gallon). This means that it would be able to start fermenting faster (although, probably only by a number of hours). I don't know what the fermentation curve looks like, but I'd guess that it starts really fast and the speed of fermentation drops logarithically (exponentially?) as it goes. It seems to me that this means that once the 5 gallon started, it would be going faster than the 1 gallon at any particular point in time. I wouldn't ever catch up exactly, but it would always be heading that direction. At any rate, it may be able to make up a good deal of the original time differential. My guess would be that technically, the smaller batch would ferment faster, but realistically, it wouldn't matter.

It seems to me that a large batch might be more resitant to environment changes (temperature, etc) and that it would almost assuredly be more tolerant to changes in ingredients. While a smaller batch would be more easily controlled environment wise but would require a more precise ingredient mix.

As far as I can tell, here are the pros and cons of different batch sizes

Larger batches:
pros:
more uniform taste across a larger number of bottles (when finished)
one batch yeilds a much higher final volume

cons:
more expensive
harder to deal with (move, etc...)

neutral:
More resistant to changes (environment, recipe, etc...)


Smaller Batches
pros:
less expensive per batch (allowing for greater experimentation possibilities)
easier to "deal" with

cons:
requires extra effort to get the same final volume
Takes up more floor/shelf space for an identical volume

neutral:
More easily manipulated (moved, racked, etc...)

Please add to these lists as you feel necessary.

Jmattioli
11-12-2004, 01:12 AM
I was wondering if anyone had noticed a time differential in any of the different stages of the process (fermentation, clearing, aging) based on the size of the batch. Specifically, do you find that a mead clears faster in a smaller container? In my case, it would because I can put the smaller container (1 gallon) in my refrigerator while my larger container (5 gallon) wouldn't fit. Also, do you find that there is generally more lees, less lees, or about the same depending on the size of the batch (per volume). How about loss during racking (more, less, about the same)?


Yes, I noticed small batches fermented faster. In my case this was due to 2 things. #1 The percentage of yeast pitched was always greater with my 1 gallon batches. #2 Most yeast I use come automatically prepackaged with some nurients and minerals to get them going. I add very little if any additional nurients. With 1 gallon batches I am fine but the yeast have to multiply more for larger batches and my fermentation speed suffers. Adding more nutrients solves this problem.

As far as lees goes, the difference per gallon is negilible. So a 5 gallon has about 5 times as much as 1 gallon. (About the same per volume.

A 1 gallon seems to clear faster for me.

Joe

ScottS
11-12-2004, 01:23 AM
My simplified understanding of the fermentation process is that the yeast multiply to a critical density, then fermentation starts. The multiplication doesn't really take all that long. When you pitch a single packet of yeast into a 5 gal container vs a 1 gal, you start with 1/5 the density of yeast. So the 5 gal batch is slightly more than 2 multiplication cycles behind the 1 gal batch. Not that long in the grand scheme of things. Assuming everything else is equal, I wouldn't expect a whole lot of difference between the two.

I haven't noticed a whole lot of difference between 1 gal, 5 gal, 20 gal, and 40 gal. All take 10-14 days. I did notice though that the 40 gal had a several day lag, even with a 5 gallon starter.

Oskaar
11-12-2004, 01:30 AM
I generally use no less than 10 g of yeast per five gallon batch. I'll mix the ingredients up in one of my 20 gallon brew kettles (not using any heat currently) and then pitch the yeast. I do add more yeast for higher gravity musts, and will on occaision make a starter at the rate of 1 litre per gallon for high gravity musts. Then I pitch the yeast, keep stirring, and decant the must into the carboys.

I don't have a real problem moving carboys or kegs around because I have some little dollys that my dad and I made that I set them on. So if I have a twenty gallon batch I'll fill up four carboys and put two on each dolly, move them over by the refrigerator in the brewhouse, and cover them to keep the light off of them.

I've had a primary fermentation rate of about two weeks per batch. Usually by that time they've slowed down enough to be racked.

Oskaar

Suzy_Q_Brewmistres
11-12-2004, 05:21 AM
I have always wondered.... what does the dark do for the mead?
Or perhaps I should ask... what does light do to the mead?
I currently have most of my batches covered with black plastic garbage bags.. but the two in the kitchen aren't. They are so pretty... I like to see them. I prolly should cover them too and move them into the nursery (bathroom)
:-* Suzy Q, Brewmistress.

Oskaar
11-12-2004, 05:28 AM
Yeasts work better in the dark, too much light can slow/kill them off to a point where the ferementation becomes stuck, or so slow you think it's stuck.

I just cover my carboys to keep the variances in the temperature a little more smooth, and to keep the yeasties happy!

Oskaar

Suzy_Q_Brewmistres
11-13-2004, 11:56 PM
Thanks Oskaar.

:-* Suzy Q, Brewmistress