View Full Version : Alcohol content testing?
If i didn't take correct readings at the beginning of my ferment is it still possible to get an accurate alcohol reading upon the end result?
Ben Brewcat
02-28-2009, 04:08 PM
Not without a lab. However, it can be approximated in a couple ways. Did you keep a record of your ingredients? If so, we can infer the starting gravity based on how much honey went into how much solution with a fair degree of accuracy. Then it's just a matter of comparing final gravity to starting gravity and the alcohol is the difference. See the intro to meadmaking thread for more on gravity calculations, or tell us how many pounds went into making how much must.
There is also a doodad called a vinometer which uses capillary action to indicate the alcohol of a finished DRY mead or wine, but it can't have residual sugars in it and they aren't highly accurate anyways. The only way to know if there are residual sugars, aside from guessing based on taste, is (you guessed it) a hydrometer measurement. Though depending on your starting gravity and yeast strain, we could probably speculate pretty accurately on your residual sugar levels.
Thanks Ben,
I made a blueberry melomel, and measured through 10 lbs of blueberries and got 1.184 as best as i could tell. Which upon reflection was wrong. I should have taken a sample of must without blueberries.
I used 16 lbs of honey for a 5 gallon batch with lavilin EC 1118.
I'm guessing it will be about 13-14 percent, without having taken a final reading yet.
It's no longer fermenting ,i think. I'm just bulk aging it right now.
How do you do a rough estimate?
THis will be nice to know because i just started a batch of orange cinnamon without having taken an origional reading at all.
Ok, i checked out the intro to mead making and have another question!
I previously mentioned the orange cinnamon i just started. This is is my 3rd batch. the first 2 batches I heated and was over anal on the sanitation thing. This time I just heated the must enough to dissolve the honey into the water. I rinsed the carboy with a bleach water then rinsed really well. Added oranges, cinnamon sticks , raisins and other goodies right to the carboy along with the must, pitched the yeast ec 1118 in the carboy and it 's been fermenting nicely for a week now. I didn't heat the must like the others and was planning to keep everythiing in the carboy until it's ALL done ( 6 months).
Questions:
How much of a mistake have i made not heating the must to kill the bad guys?
When do you know if the yeast hasn't killed bad bacteria?
Should I still rack after primary ferment or can I leave everything in the carboy for 6-8 months?
Ben Brewcat
03-01-2009, 02:02 PM
In theory, suspended solids shouldn't affect a gravity reading by themselves (they don't change the density of a liquid), but if they physically move/restrain the thistle then it'll skew. If the hydrometer was placed through the cap of berries, it probably did have a hard time getting a good float.
Um, OK. 16 pounds of honey at 37 ppg (points/pound/gallon) makes for 592 gravity units. 592 GUs divided into a 5-gallon must makes for an estimated OG of 1.118 from the honey (or a potential gravity of a frog's hair over 14%).
It'd be a matter of estimating how many sugars are derived from 10 pounds of bloobs, which is way outta my brain league. Anyone have some gravity figures on blueberries? Were they frozen, pureed or otherwise had the sugars freed or were they whole berries? My guess would be that you had maybe around an 18% potential must, right around the alcohol tolerance of your champagne strain. You might even have some residual sugars in the mead, depending on yeast performance and of course how much sugar came from the bloobs. Yum! I like some sweetness with blueberries; the character seems to disappear in a dry mead but is more evident with a little sweetness.
Note that nerds like me aside, your mead will taste the same whether you know the gravities or not :). But for those who want to target their meads for sweetness or alcohol content, or to know how their yeast is performing, or who miss chemistry class and fun labby toys, a hydrometer is a great idea.
Ben Brewcat
03-01-2009, 02:13 PM
I didn't heat the must like the others and was planning to keep everythiing in the carboy until it's ALL done ( 6 months).
Questions:
How much of a mistake have i made not heating the must to kill the bad guys?
When do you know if the yeast hasn't killed bad bacteria?
Should I still rack after primary ferment or can I leave everything in the carboy for 6-8 months?
Heating or not heating, folks make goods meads both ways. I guess for my $.02 it's not so much not having heated as introducing the spices and their load of microbial hitchers in the primary rather than the secondary (when pH is lower, the yeast is active already and there's alcohol).
It's almost unheard of for there to be NO wild yeast or bacteria in a batch, that's the difference between sterilizing (virtually impossible) and sanitizing. It's a numbers game; the more attrition of the undesirables, the less character they'll contribute. The stronger your yeast, the more it'll outcompete the creepies. Your 1118 is a strong strain; not the "killer strain" like K1-V but hearty nonetheless. It usually does pretty well in that regard.
As to racking, I do like to rack at some point to get off a big pile of spice debris and yeastcake, but there's no real rush. The only thing about racking to insert here (well, besides never suck-start a siphon) is that every racking costs mead, oxidizes a little, and is a potential source of contamination. That said, with careful technique racking is very helpful. It drives off excess CO2, oxygenates just a little for yeast to finish their jobs and start some maturation changes, and can help clarify. You also get to taste a little :) and maybe take a hydrometer reading.
[QUOTE=
Note that nerds like me aside, your mead will taste the same whether you know the gravities or not :). But for those who want to target their meads for sweetness or alcohol content, or to know how their yeast is performing, or who miss chemistry class and fun labby toys, a hydrometer is a great idea.[/QUOTE]
Thanks Ben,
I'm more interested in the flavor, but was curious about the alcohol content.
[QUOTE=Ben Brewcat;399574]Heating or not heating, folks make goods meads both ways. I guess for my $.02 it's not so much not having heated as introducing the spices and their load of microbial hitchers in the primary rather than the secondary (when pH is lower, the yeast is active already and there's alcohol).
So I should have waited to put the spices in after the primary ferment?
When will i know if i have vinigar?
Does the primary kill some of the potential flavors of the cinnamon , cloves and raisins?
Ben Brewcat
03-02-2009, 10:36 PM
So I should have waited to put the spices in after the primary ferment?
Not necessarily "should" have, just an option. I like to for those reasons, and that aromas can get scrubbed by the prodigious CO2 offgassing a primary puts out. But it's not a big deal, I'm personally a bit of a freak about optimizing (it's a nerd thing) and frankly there are bigger fish to fry.
When will i know if i have vinigar?
You won't. Certainly not from adding those spices in the primary, I hope I didn't give that impression. Besides, vinegar comes from a combination of acetobacter inoculation, usually from fruit flies entering a poorly-tended airlock, but then they also need oxygen to convert alcohol into acetic acid. Most contaminations are subtle; slight off-flavors or even loss of flavors, hazes, rings on bottles, and then of course the occasional sour/medicinal/eek drain cleaner :).
Maybe i'll give a touch more spice after a bit of a taste in a few months.
It sure smells great.
cool to see that the primary fermenting has broken the orange cells and released the juice.
thanks for the input.
i'll post the results in a year.......patiently waiting!
nursebee
03-03-2009, 06:42 PM
BJ, send me two bottles and I will run it through my lab set up. I'll let you know the ETOH content. Send me a PM for address.
Not necessarily "should" have, just an option. I like to for those reasons, and that aromas can get scrubbed by the prodigious CO2 offgassing a primary puts out. But it's not a big deal, I'm personally a bit of a freak about optimizing (it's a nerd thing) and frankly there are bigger fish to fry.
You won't. Certainly not from adding those spices in the primary, I hope I didn't give that impression. Besides, vinegar comes from a combination of acetobacter inoculation, usually from fruit flies entering a poorly-tended airlock, but then they also need oxygen to convert alcohol into acetic acid. Most contaminations are subtle; slight off-flavors or even loss of flavors, hazes, rings on bottles, and then of course the occasional sour/medicinal/eek drain cleaner :).
Upon further reflection, I put the primary in a pail with a lid ajar..and put in a a dishwasher converted into a warming box. In late September i did have some fruit flies buzzing in and out...of course infatuated with the smell and sights i was opening the pail every 2 days. I'm sure some flies were in the pail on top of a heavy coating of blub's. After 2 weeks into a carboy. It was still over active and blew the burper off for another week but there was no flies around at that point.
Would this cause a problem? I racked off the mead about 3 weeks ago and had a taste. It was tasting a bit like young wine but certianly wasn't nasty.I thought bulk aging for another 6 months or so would do wonders.
When do you know if this acetobacteria's kicked in?
BJ, send me two bottles and I will run it through my lab set up. I'll let you know the ETOH content. Send me a PM for address.
Thanks for the offer...but i have my own tester in mind...in about 10 months. :D
The cost and hassles to send down there would be insane.
Cheers
nursebee
03-04-2009, 07:39 PM
AY agree. Gives me an idea though.
Well , not quite a year yet.
I actually did two batches: one with my early golden honey and 1122 yeast.
It cleared in the summer and had a REAL nice orange citrus taste and was super smooth...was 1 gallon and didn't last long.
Batch 2 was with different honey and 1118 yeast...wow what a difference in taste and smoothness...this one has a real bite and took longer to clear and isn't smooth yet. Still drinkable but not bragging material like the first. I'll do it again with the first recipe.
Swobee
12-21-2009, 07:56 AM
I have a Vinometer. But have to admit I only used it once or twice and never compared the reading with math formula of Original Gravity vs Ending Gravity. I suppose they are a reasonable guesstimate of content.
hpm08161947
02-03-2010, 06:41 PM
I know this method of Alcohol calc works for wine - wonder if it would work for mead?
If you have both a narrow range hydrometer to get specific gravity and a refractometer you can estimate the alcohol content using the following equation...
=0.365*(4.16*RB-1000*SG+1000)
RB = Refractometer reading in Brix
SG = Hydrometer Specific Gravity
mike haney
02-03-2010, 07:58 PM
I have a Vinometer. But have to admit I only used it once or twice and never compared the reading with math formula of Original Gravity vs Ending Gravity. I suppose they are a reasonable guesstimate of content.
i've got one too and you can get nearly as close by tasteing. good luck,mike