Batch size calculation

I made a mead today with 12.75 pounds of honey and topped it with water to make 5 gallons total.

On beersmith I'm trying to calculate the gravity/ABV so would batch size be 3.50 gallons or 5 gallons? I think the 12.75 pounds of honey was roughly 1.5 gallons so there would be 3.5 gallons of water. Thanks in advance!

Your batch size is 5 gallons, if you made a 5 gallon batch.

If you want a simple method to do this calculation (and others), then download the Mead Calculator Spreadsheet (XLS) for the Mead FAQ topic.

Enter 12.75 in the Honey Lbs cell, and then adjust the water volume column "V(C)" to 63 and you find that your batch size is 5.02 gal, the OG is 1.090, and the expected ABV at a FG of 1.000 is 11.9%.

If you employ a staggered nutrient protocol, the spreadsheet automatically calculates the corresponding nutrient add points.

And , if you use a refractometer, it provides the means to determine SG readings (adjusted for the presence of alchol) as the fermentation progresses...

This does bring up a point I've been muddling around---an issue with recipes:

I've pieced together the idea that the ratio of honey to water can vary between 1lbs per "gallon" to 5lbs per "gallon"

Of course, honey (having a mass of its own) takes up space too...

So I think its best to read this as 1 - 5 lbs of honey per gallon of must.

Therefore all those recipes you read that say "for a 5 gallon batch you need 5 gallons of water, 10 lbs of honey..." are just plain lying to us! Or maybe that extra water is for cleanup...

Driftless said:

...Of course, honey (having a mass of its own) takes up space too...

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The Mead calculator spreadsheet accounts for the honey volume in the final results.

True...

However, the point I think I am making (if there is a point here) is the inconsistency in reporting... Which probably is just "one of those things."

For example, in reporting a 3 Gallon recipe many say:

3 Gallons water
10 lbs honey

When, the recipe should be 2.15 gallons of water, 10 lbs honey...

Of course it would be most useful to say: 4.64 lbs of honey per gallon of water, or 3.333 lbs of honey per gallon of must for recipe scaling.

Unless someone has the spreadsheet in front of them, it could be confusing.

Minor point... just rambling. Of course, the only formula one really needs to know is: water + sugars + yeast + time = happiness

I have noticed this as well. It can be a bit confusing, even on the spreadsheet. Its all good though, most of us get there in the end.

Driftless said:

True... However, the point I think I am making (if there is a point here) is the inconsistency in reporting... Unless someone has the spreadsheet in front of them, it could be confusing.

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Your point is most valid. One may find recipe inconsistencies, oversights, and errors in many places - even Ken Schramm's book has them. Newer brewers, who lack the experience to identify these issues, simply follow the recipe and find the results are not always successful.

I'm not suggesting that this happens intentionally, but it happens and it is why I always check as much information as possible about a new recipe before making it. One reason the mead spreadsheet was developed was to give others the means to do the same...

I don't even deal with units of honey. I just start with about 3.5 gallons of water and keep adding until I get my desired sg.

Ive seen a lot of recipes written as: 10 lbs honey, and water to reach 5 gallons.
Would that be a more accurate way to write it?
Generally, how much does honey weigh? Like a liter or a gallon of honey would generally weigh how much?

1 gallon = 12 lbs. But this will vary based on moisture content.

So 10 lbs of my honey won't have the same amount of sugar as 10 lbs of your honey.

BigStone777 said:

..Generally, how much does honey weigh?

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The weight of honey is dependant upon its moisture content. Typically, most honey is ~17.2% moisture, and at that level its weight per gallon is 11.808 Lbm/gal. Some use a thumb rule of 12Lbs/gal.

A study by the National Honey Board (NHB) in Sept. 2003 found a statistical sampling of honey had a moisture content range from 13.4-22.9%. The average of their honey samples was 17.2% (with a SD of 1.46%).

Are we talking about the volume honey displaces in water when dissolved?
I know I am always under/over stating my efforts; trying to find a better way.
If I could work out displacement for a quantity of water, would have it sussed.

petes said:

Are we talking about the volume honey displaces in water when dissolved?

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I'm not sure I understand what you're trying to understand.

However, 1 gal of honey having a typical moisture content of 18% weighs about 11.8 Lbm. When mixed with "x" gallons of water the total volume of the mixture follows the equation: ChVh +CwVw = CtVt (where C is a concentration, V is volume, h is honey, w is water, and t is total). It is the basic dilution equation used in the mead calculator spreadsheet, and it can be easily used to adjust mead recipes to fit into particular size of primary (I do it all the time...)

Well maths was never my strong point so whilst I was aware of the spreadsheet, I've stayed away from it.
Trying to keep things simple, I know that a quantity of honey dissolved in water increases its volume.
Typically I've been weighing my honey out of bulk - it's solid - and dissolving it in my measuring jug adding hot water to the 2 litre mark. Except I've been completely overlooking the fact that for final must volumes, my 2 litres wasn't; so I wondered if there's a 'rule-of-thumb' that could apply?
I'm putting down an ugli melomel this arv and smartening my act so I'll finally get it right. (Perhaps too I'm just doing it all arse about )

petes said:

Well maths was never my strong point so whilst I was aware of the spreadsheet, I've stayed away from it.

Click to expand...

That's the beauty of the spreadsheet - you don't need to do the math, it does it for you.

The spreadsheet is also protected so that you can't inadvertently erase any of the important "stuff".

Unfortunately, I'm not a "rule of thumb" type of person. Details, and knowing how (and why) things work is my forté...

Damn... anyone know a good way to test the moisture content?

Not that it matters tooo much, but after I've had a few, I either don't give a sh*t or I turn into a formula geek and try to hash it all out...

The spreadsheet isn't working for me. I change values, and none of the calculations change.

It may be because I'm using Excel 2007.
It opened in compatability mode, and wouldn't calculate, so I converted it, and it still doesn't work.

Driftless said:

Damn... anyone know a good way to test the moisture content?

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Accurately measure the weight of a known volume of honey, or measure the SG...

Plan9 said:

The spreadsheet isn't working for me. I change values, and none of the calculations change. It may be because I'm using Excel 2007.

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I'm sorry you're not able to use the spreadsheet. It was built using Excel 2003. Is Excel 2007 not backwards compatible with the 2003 version?

So far, you're the only person who's mentioned this issue. I wonder if other Excel 2007 users are having the same problem?

Are you certain you're not try to change a protected cell value? See the spreadsheet's legend.

plan9,

I did a little research and there is a compatibility issue using Excel 2007 with XLS files. However, there is a way in which you should be able to use the Calculator Spreadsheet.

Microsoft has a Microsoft Office Compatibility Pack that is designed to allow Office 2007 users to work with earlier office files. I hope it works for you.

I use excel 2007 and didn't have a problem. The spreadsheet is very helpful by the way, thanks.

BBBF said:

1 gallon = 12 lbs. But this will vary based on moisture content.

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This is a very marginal amount of fluctuation. Unless your honey looks runny, or you're making a 10,000 gallon batch, the variation is a moot point. It simply won't throw off your calcs by that much. You will likely have more of a variation in where you consider the "Full Mark" on your carboy than the moisture content in a gallon of honey.