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Paladin906
10-28-2014, 11:23 PM
My question regarding residual sugar is twofold: 1) How can I accurately measure the residual sugar of my final product without using the clinitest strips or requiring the use of a small chemistry lab? 2) Is their a method to use OG and SG to end your mead with the desired ABV and residual sugar? For example, if I am shooting for an ABV level of 18% I know that I need an OG = 1.14 and an ending SG of 1.004. But what if I wanted to also end with a residual sugar of say 7%? Is there a calculator that can tell me what changes in OG or end SG is needed to achieve this?

Paladin906
10-30-2014, 03:43 PM
For all who are interested, my research has revealed this thread on another forum. Very interesting read.

http://www.winepress.us/forums/index.php?/topic/39644-figuring-residual-sugar/

Midnight Sun
10-30-2014, 04:33 PM
Try the mead calculator here (http://www.gotmead.com/2014-04-16-20-10-09/mead-calculator.html), see potential alcohol converter somewhere near the middle. Use the Brix scale, Brix ~ %sugar.

Using your example of 18%ABV, 7% residual sugar, I get: OG = 38Brix, FG = 7Brix.
Converting to gravity: OG = 1.169, FG = 1.028.

Note that this would just be an approximation. The difference in alcohol probably throws off the calcs a little. Would be good too if someone checks my work.

Paladin906
10-31-2014, 12:10 AM
Thanks Midnight,

I didn't realize that brix approximates residual sugar.

Chevette Girl
10-31-2014, 01:34 AM
Just a comment... the yeast haven't read the package and don't always stop where the lab says they're supposed to, and starting with a really high SG is not going to get you a really high alcohol content because it's too hard on the yeast.

By all means calculate out the amount of honey you'd need and use that in a batch so you know how much alcohol you'll have at the end of it all, but if you add it all up front (especially something like 1.169), your yeast are not going to be at their best and will probably poop out early and leave you with something way sweeter than anticipated.

If you want a residual sugar and the yeast maxxed out for alcohol percent, step-feeding is your friend.

If you just want a particular residual sugar for taste, go conservative, ferment dry, stabilize and backsweeten to taste.

Even just measuring the finishing SG you're not going to be as accurate as you'd like, you can still end up with small amounts of sugar present in a must below 1.000 because of the ethanol.

Paladin906
11-02-2014, 11:16 PM
Just a comment... the yeast haven't read the package and don't always stop where the lab says they're supposed to, and starting with a really high SG is not going to get you a really high alcohol content because it's too hard on the yeast.

By all means calculate out the amount of honey you'd need and use that in a batch so you know how much alcohol you'll have at the end of it all, but if you add it all up front (especially something like 1.169), your yeast are not going to be at their best and will probably poop out early and leave you with something way sweeter than anticipated.

If you want a residual sugar and the yeast maxxed out for alcohol percent, step-feeding is your friend.

If you just want a particular residual sugar for taste, go conservative, ferment dry, stabilize and backsweeten to taste.

Even just measuring the finishing SG you're not going to be as accurate as you'd like, you can still end up with small amounts of sugar present in a must below 1.000 because of the ethanol.

Thanks for the input. I like the idea of step feeding because I'd rather practice and develop techniques that would end my ferment at a predetermined alcohol and residual sugar level so that I can avoid back sweetening. However, I do realize that the best laid plans go awry. I worked with yeast in a microbiology lab when I was in college. Getting them to do what I wanted was a challenge back then as it is now.

Chevette Girl
11-02-2014, 11:37 PM
Thanks for the input. I like the idea of step feeding because I'd rather practice and develop techniques that would end my ferment at a predetermined alcohol and residual sugar level so that I can avoid back sweetening.

...actually, if you want a predetermined alcohol content, then you will predetermine your alcohol content by using a specific amount of honey, ferment it dry, and then to prevent any further change in the alcohol level, stabilizing and backsweetening is the way to go. Step feeding will end it with a residual sugar level within the range you set, but the alcohol level could be anywhere between a few percent below the lowest expected rating and a few percent above the highest expected rating. Because, you know, yeast.

And as usual, there are risks with step-feeding. The closer you get to the end of the yeast's alcohol tolerance, the more stressed the yeast will be so the slower it will get and the more likely it will be to throw off flavours or odours as it struggles to survive in an environment that's getting more and more toxic. Most of the time when step-feeding, you end up with something strong and sweet enough to cover anything like that, but there's always the risk. And it's also something that's going to need more aging because of the higher alcohol content, it'll taste "hot" for longer than a lower-gravity ferment.

Now, if you'd said you didn't want to backsweeten because you don't like using chemicals, that's different, it's a choice you make and most of us can respect that. Just don't assume that you might make a better or more controlled product without using the chemicals.

joemirando
11-03-2014, 12:01 AM
Thanks for the input. I like the idea of step feeding because I'd rather practice and develop techniques that would end my ferment at a predetermined alcohol and residual sugar level so that I can avoid back sweetening. However, I do realize that the best laid plans go awry. I worked with yeast in a microbiology lab when I was in college. Getting them to do what I wanted was a challenge back then as it is now.

I had one batch that I had planned on/provided honey for an ABV of 16%, but when it got to 14, I liked the balance of taste and kick, so I cold-crashed it, racked it onto campden tablets and K-sorbate, and bottled the sucker a day or two later. It turned out quite nice.

My point is not that you need to cold crash, but that there's more than one way to skin a mead. <Grin>
Step feeding is a very interesting experience. It'll take you back to microbiology. Just remember to leave room for the honey you will/might add down the line. For instance, if you're making a gallon batch and are going to be step feeding a pound of honey each time for three feedings (this is just an example), you need to leave about a quart of space for that honey from the start.

To quote Norm Crosby: A word to the wise is deficient! <grin>

Joe

Paladin906
11-03-2014, 09:13 PM
Just remember to leave room for the honey you will/might add down the line. For instance, if you're making a gallon batch and are going to be step feeding a pound of honey each time for three feedings (this is just an example), you need to leave about a quart of space for that honey from the start.


Joe

This was a lesson learned on my first batch and was my first posting on this forum. I definitely leave room in my primary for foam, add ins, etc.