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Mishram
01-19-2016, 03:33 PM
This is my first post so please take it easy on me.

I have a muscadine mead that I'm ready to bottle. I would like to back sweeten to a semi-sweet mead and according to "The Compleat Meadmaker" the SG of a semi-sweet would fall in the SG range of 1.006-1.015. I don't like very sweet meads so I want it in the lower range of sweetness. My FG is 0.996. It seems like if I aim for 1.06 it's going to be overly sweetened, since it will take a certain amount of sugar just to bring it up to 1.00. Am I even thinking about this correctly? Is there a better way to do this and be consistent when FG can vary 0.994 to 0.998 from one batch to the next?

I had a couple batches last year that I sweetened to taste, then when they mellowed out they were way too sweet. So this time around I am taking a different approach. Ideally I would like to bulk age it and sweeten after it has mellowed but I need this carboy for my next batch.

Thank you in advance.

Squatchy
01-19-2016, 08:47 PM
It wouldn't really matter where your "g" started at. It's the hydrometer that will give you your final figure. If your worried about it bring it up to half of what you think you might like. Once you get there go slower and bring it up slowly and test it a few different times spread over a couple days so you have a good feel for things.

Mazer828
01-20-2016, 02:01 AM
One way to start is to pick a yeast with a fairly predictable track record, like 71B-1122. It'll take you right to 13-14% ABV every time if you treat it right. And if you rack from the primary to a secondary you can almost always guarantee it'll go about 10 more points and stop. So set up a recipe that will start you off with about 13-14% ABV worth of fermentable sugars (OG of about 1.100-1.110), a little more if you want it to end up sweeter, a little less if you want it to end up drier. Then when it gets around 10 points higher than you want it to stop, rack it. It's not an exact science but it works fairly well.

Mishram
01-20-2016, 05:46 PM
Thanks Mazer, I was not aware of that little tidbit about the gravity change after racking! I will have to try that on my next batch. My method has always been just put enough sugar to get my target abv because I was afraid otherwise it could get too boozy. I need to have more faith in my yeast.

Squatchy
01-21-2016, 04:52 AM
Thanks Mazer, I was not aware of that little tidbit about the gravity change after racking! I will have to try that on my next batch. My method has always been just put enough sugar to get my target abv because I was afraid otherwise it could get too boozy. I need to have more faith in my yeast.

It's always easy enough to just add some juice to it if it's "too boozy"

EJM3
01-21-2016, 03:47 PM
Also when back sweetening I have found the best success when: I would mix well until completely dissolved, wait half of an hour to an hour, swirl lightly then pour. I would find that if I sampled it after everything looked dissolved it would taste so so, then later it would taste too sweet. IME YMMV

Mishram
01-21-2016, 04:18 PM
It's always easy enough to just add some juice to it if it's "too boozy"

Very true. It's easier to fix "too boozy" than "not boozy enough".

Squatchy
01-21-2016, 04:55 PM
That's just as easy. Add vodka, rum or everclear

Sent from my SAMSUNG-SM-G870A using Tapatalk

Mishram
01-27-2016, 03:47 PM
Here's an update on the batch I back sweetened.

I wanted to shoot for a semi sweet to semi dry mead, so I plugged numbers into the mead batch calculator to figure out much honey to add to bring the SG up to 1.006 in 3.5 gal (I'm not sure if this is the right way to calculate this, but I have no idea how else to do it). So I added the amount, stirred, waited, stirred again, tasted, decided to make it a little sweeter. So I recalculated for 1.01, stirred, waited, stirred. I dropped the hydrometer in and it read 1.004

The conclusion that I am coming to is the residual sugar in a batch where the ferment stopped at 1.01 will be less than the amount of sugar added to a fully fermented batch that was back sweetened to 1.01. I know there is some science here that I just don't understand and I would really like to understand it.

Can someone shine a light on this?

zpeckler
01-27-2016, 04:52 PM
You're on the right track... Specific gravity is a measure of the density of a fluid relative to pure (i.e. distilled) water. A fluid with the same density has a gravity of 1.000. A fluid with a gravity of 1.050 is 1.050x as dense as pure water. In the world of alcoholic beverage making we know that adding sugar increases the density of the must, and thus the specific gravity. Gravity is not a direct measure of sugar concentration.

Alcohol, on the other hand, is less dense than water. As your yeast go to work and ferment all the sugar into alcohol, the gravity decreases because there is less sugar (which makes the must more dense) and more alcohol (which makes the must less dense). This is why a dry mead can sometimes have a FG less than 1.000, because the alcohol in the final mead makes it slightly less dense than water. When making bone dry traditionals I routinely see a FG of about 0.995.

I think what's going on here is that the batch calculator is crunching the numbers under the assumption that there's no alcohol in the batch. Let's say you add enough honey to get the expected 1.010 but it's only 1.004 when you measure it; I think it's because the alcohol is making the must less dense than the batch calculator expects.

TL;DR... Batch calculators are great to get rough estimates, but the numbers are just starting points. Keep adding small amounts of honey until you're satisfied with the taste!



(Also... What's an additional variable is the moisture content of honey. In general is about 75-80% sugar, 20-25% moisture, but there is a bit of wiggle room. For example, if you made two musts with the same amount of two different honeys they will probably have slightly different starting gravities.)

Mishram
01-27-2016, 05:48 PM
You're on the right track... Specific gravity is a measure of the density of a fluid relative to pure (i.e. distilled) water. A fluid with the same density has a gravity of 1.000. A fluid with a gravity of 1.050 is 1.050x as dense as pure water. In the world of alcoholic beverage making we know that adding sugar increases the density of the must, and thus the specific gravity. Gravity is not a direct measure of sugar concentration.

Alcohol, on the other hand, is less dense than water. As your yeast go to work and ferment all the sugar into alcohol, the gravity decreases because there is less sugar (which makes the must more dense) and more alcohol (which makes the must less dense). This is why a dry mead can sometimes have a FG less than 1.000, because the alcohol in the final mead makes it slightly less dense than water. When making bone dry traditionals I routinely see a FG of about 0.995.

I think what's going on here is that the batch calculator is crunching the numbers under the assumption that there's no alcohol in the batch. Let's say you add enough honey to get the expected 1.010 but it's only 1.004 when you measure it; I think it's because the alcohol is making the must less dense than the batch calculator expects.

TL;DR... Batch calculators are great to get rough estimates, but the numbers are just starting points. Keep adding small amounts of honey until you're satisfied with the taste!



(Also... What's an additional variable is the moisture content of honey. In general is about 75-80% sugar, 20-25% moisture, but there is a bit of wiggle room. For example, if you made two musts with the same amount of two different honeys they will probably have slightly different starting gravities.)

Great! I knew the density of alcohol had involvement in this somehow, your explanation really helped things come together in my head.

This opens the door to more questions though! I'm still stuck/confused about the gravity range for dry, semi sweet, sweet, dessert. A mead at 19% ABV and a hydromel at 6% that are both semi sweet would not be close to the same gravity because of the difference in alcohol, right? So, if you want to get into submitting your meads into competition or to sell, and your goal is to create a semi sweet, how do you go about measuring the sweetness in your mead to make sure it in the correct range? Do you just have to be that experienced in tasting it and then go by taste? It seems like you have to throw out the hydrometer at this point. Or are there rules when it comes to back sweetening, instead of going by gravity you go by a measurable amount of sugar/gal?

Mazer828
01-27-2016, 06:29 PM
Taste is not an exact science. Let's just start there. Because every qualifier of taste is subjective, so don't look for hard and fast answers.

That being said, the sweetness or dryness of a mead CAN be related to its final gravity. Remaining, or residual, sugars in the mead play a large part in determining whether the taster will perceive the mead dry or sweet. There is also something called perceived sweetness, which can be present even in a mead with little actual residual sugar. I find that body/mouthfeel can make a mead seem sweeter, even though it isn't necessarily sweet. Likewise, certain acids like citric acid can give a candy-like flavor that makes the taster perceive sweetness. More experienced mead tasters can probably weigh in here and use this as a spring board to launch into a ton of other factors, but I hope I've made my point.

If you want some rough guidelines, I believe the BJCP/MJCP guidelines actually help provide some boundaries to help properly categorize a mead as either sweet, semi-sweet, or dry.

Hope that helps.

Mazer828
01-27-2016, 06:35 PM
Here's what the BJCP guidelines actually say about sweetness:

Sweetness. A mead may be dry, semi-sweet, or sweet.
Sweetness simply refers to the amount of residual sugar
in the mead. Sweetness is often confused with fruitiness
in a dry mead. Body is related to sweetness, but dry
meads can still have some body. Dry meads do not have
to be bone dry. Sweet meads should not be cloyingly
sweet, and should not have a raw, unfermented honey
character. Sweetness is independent of strength. Note
that tannin levels can affect the perceived sweetness of
mead (more tannin makes a mead seem drier), but
acidity is more related to the quality, balance, and
enjoyment of the sweetness. The purpose of identifying
a sweetness level is primarily to aid in the ordering of a
flight. Minor differences from stated sweetness level
should not be heavily-penalized or considered a
disqualifying fault.

zpeckler
01-27-2016, 06:48 PM
This opens the door to more questions though! I'm still stuck/confused about the gravity range for dry, semi sweet, sweet, dessert. A mead at 19% ABV and a hydromel at 6% that are both semi sweet would not be close to the same gravity because of the difference in alcohol, right? So, if you want to get into submitting your meads into competition or to sell, and your goal is to create a semi sweet, how do you go about measuring the sweetness in your mead to make sure it in the correct range? Do you just have to be that experienced in tasting it and then go by taste? It seems like you have to throw out the hydrometer at this point. Or are there rules when it comes to back sweetening, instead of going by gravity you go by a measurable amount of sugar/gal?

Like most things in meadmaking, it's all relative. ;)

The gravities in The Compleat Meadmaker are the commonly accepted ranges for the different sweetness levels in a final mead. It's perfectly ok to say that because your mead has a certain final gravity it's in one category or another.

The drinker's perception of the sweetness of the beverage is what can be relative. There are innumerable things that can change how sweet a mead seems to someone's pallet. For example, higher acidity can make a mead taste less sweet, and lower acidity can make the same mead taste sweeter.

If you want to get reeeaaaalllly technical about it, a 19% and a 6% mead at the same gravity will have different concentrations of sugar thanks to the changes in gravity from the different amounts of alcohol. The effect is slight, though. I don't know what the equation would be to compensate, but honestly going to the trouble to do all that math is outside the scope of a commercial meadmaker, much less a guy in his basement with a few carboys. Without a sophisticated lab I don't know of a way for a home meadmaker to directly measure sugar/gal.

At the end of the day, figure out what FG you generally like your meads to be at and shoot for that. It'll probably vary batch to batch, recipe to recipe. The numbers should be a guide, but ultimately meadmaking is an art so let the taste of your mead and your growing experience make the final decision. Don't add all the honey you think you'll need right away, though. Add a little honey, dissolve, taste. If it needs more, add more. You can always make it sweeter, but if you overshoot it's more is a difficult situation to correct.

Mishram
01-27-2016, 09:35 PM
Thanks for the replies. this has been a huge help. I've been a home wine maker for a while and have only been into mead making for a year. Since honey is pricier than sugar I hate to mess up a batch so I want to do everything right. It would be so much easier if I could crunch numbers to get it exactly how I want it. This does explain a lot about past wines I've made. I had a lot of comments on how sweet an elderberry wine was, and I kept saying it's actually on the dry side...but apparently I was tunnel visioned on the hydrometer reading while everyone else was just TASTING it.

Stasis
01-28-2016, 03:23 AM
If you want to get reeeaaaalllly technical about it, a 19% and a 6% mead at the same gravity will have different concentrations of sugar thanks to the changes in gravity from the different amounts of alcohol. The effect is slight, though. I don't know what the equation would be to compensate, but honestly going to the trouble to do all that math is outside the scope of a commercial meadmaker, much less a guy in his basement with a few carboys. Without a sophisticated lab I don't know of a way for a home meadmaker to directly measure sugar/gal.

Actually it's really simple. If you grab an amount of mead and boil it down to half its volume the remaining volume would be absent of practically all alcohol. I have tried this and measured with a precision scale hydrometer and confirmed it to be true. The remaining volume would therefore show a hydrometer reading influenced only through sugars. So if you had two dry meads of different strength and did this test you can see that one of them, in fact, has a certain amount of gravity points more. However, this increase in sugar would still not translate directly to increased perception in sweetness since more alcohol probably negates some of that extra sugar.

You could also calculate how much more sugar a batch should have through this link https://www.google.com.mt/url?sa=t&source=web&rct=j&url=http://valleyvintner.com/Tips%26Links/MeasuringAlcohol.pdf&ved=0ahUKEwiRz-Gc9cvKAhVC6RoKHb4tBsEQFggYMAA&usg=AFQjCNGi2J2FTxLq0sGlvTZdQFRc-8Nm7w&sig2=qvXoDA6sOMUQw6VJNWwrvQ
Now that link is used to calculate alcohol when it is an unknown. But if you are sure you know the exact alcohol you could reverse engineer it to calculate the difference in gravity points from unboiled to boiled... from the table provided we see that at higher gravities 16% and up, each extra 1% abv would provide an extra 0.001 gravity. At lower alcohol levels this ratio changes and 12%, for example, it is nearer to 0.9% meaning an extra 0.001. At lower still it would be 0.8%...... but this is overly complex and unnecessarily precise.
You could just assume 1% abv difference translates to roughly 0.001 sg difference unless the gravities are as extreme as your example. In your example you might add an extra 0.001 to be precise

zpeckler
01-28-2016, 06:59 AM
Must... resist... urge.... to nerd out over a new data point.... :D

Mishram
01-28-2016, 11:37 PM
Must... resist... urge.... to nerd out over a new data point.... :D

I was under the impression this was a "nerd out" safe zone ;)

Mazer828
01-29-2016, 01:19 AM
I could agree with you. But then we'd both be wrong.