Have a few quick questions - calculations etc..

[gkannon77]

So i made my first 2 batches of mead.
1 gallon carboy, each. I did not have a hydrometer at the time, so sadly I did not obtain OG readings. I have since purchased one and have been taking readings.

Both of the following batches used D47 yeast. I also followed yeast nutrients schedule of day 1, day 2 and day 5. I degassed regularly by shaking.

1st batch was made on 12/4. It has 3# honey, 1/2 gal honeycrisp apple cider, the other 1/2 gal spring water (although I used a bit less of each of course due to the honey and fruit volume offsets, as well as making sure I didn't fill past the curve... so I'd expect this OG to be a decent bit higher than 1.110). I also added chopped fresh blueberries (learned frozen may be better due to cell wall rupture), some hibiscus flowers, and some raspberry tea. Was shooting for a sweet, mildly tart, berry flavored reddish mead. I realized I should have K.I.S.S, and decided to make my second batch a little more basic, the following day.

2nd batch was made the next day on 12/5. It has 3# of honey and 1 gal spring water. A few craisins (didn't have raisins) and black tea was tossed in (some dude on YT said to toss these in, didn't think it would hurt).

My best guesses on OG for these 2 (correct met if this is wrong):

1st batch:
(1/2 apple cider and 1/2 water)
From a cursory search it appears that sweet apple cider has a SG of ~1.050. however since I used 1/2 cider and 1/2 water, I'm guessing the OG of liquid before adding 3# honey was around 1.025.... fair? Now, I also read that adding 1# honey per 1 gal water adds 0.035 SG points. I don't imagine it will.do the exact same to a mix of sweet cider and water, but for the sake of simplicity, I'll assume it adds 0.030 to that mix. So 3# will add 0.090 to my 1.025 cider/water = 1.115.

Not familiar with SG in various musts... Does that sound close to right?? Ok, on to the easy one.

2nd batch:
since I followed an exact recipe on YT for this batch (3#/1gal water) I'll assume my OG is close to his, which was 1.110.

-----------------------------------
Readings so far:

1st Readings - Dec 7th
1st batch: (3 days in) -> 1.056
2nd batch: (2 days in) -> 1.046

2nd Readings - Dec 14th (no activity at either airlock)
1st batch: (10 days in) -> 1.013 -> 13.7%
2nd batch: (9 days in) -> 0.993 -> 15.5%

Some questions:

- Are my assumptions and calculations about the potential OG of batch #1 acceptable?

- Can meads be done fermenting this quick (9 days)? I mean from what I've read if it's <1.000 it's definitely done... yeah?

- I am assuming batch 1 may still be fermenting, just very slow, since it had the added sugar from the sweet cider, and it's not down to 1.000 yet

- if I'd prefer to have that batch (1) a bit sweet, can I add potassium sorbate now while still in primary carboy, or is it better to let finish fermentation and back sweeten? I'm leaning towards the latter, but that adds another step to this process and I've never done any of this before.

 

[CKuhns]

1st batch i would suggest is 1.130 OG.
1.050 estimated cider cut in half with water = 1.025. Sounds correct to me.
3 pounds of honey to make a total volume of 1 gallon (Assumes 1 gallon volume) will in fact be betweemn .032 and .038 per pound depending on the honey and whatever calculator you believe. I generally default to .035. As such .035 X 3 = 1.105

Finally .105 + .025 gives you 1.130 when you add it to the water.

To calculate alcohol:
OG - FG X 131.25 = ABV
OG 1.130 - FG 1.013 = 0.117 X 131.25 = 15.3 ABV
Note this is not 100% accurate as it is not completely linear and the higher ABV the worse it gets. But gets you within a few tenths.

2nd batch
Same calculation
1.110 - 0.993 = 0.117 interestingly the same as above. 15.3 ABV

Can meads be finished in 9 days? I suppose they can... If your hydrometer says its done then you are. Good one on ya.
- I have been making mead for nearly 11 years and with an OG of 1.110 to 1.130 i have never had one finish that quickly. Although i have only done 5 gallon batches.

Batch one certainly may be still fermenting very slowly. D47 can slow down but will continue to work. The rule of thumb i use is if 2 gravity readings 7 to 10 days apart with no change then your likely done.

Yes you can add the chemicals to inhibit the yeast now as long as an active ferment is not ongoing. Then sweeten. I prefer to wait until its done sweeten and pasteurize. ( I am sensative to the chemicals and dont use them.)

Someone else should probably weigh in as my assunptions are just that. But i certainly think you are on the right track.

 

[gkannon77]

Gotcha, I rounded down on the first batches OG because intuitively adding honey to a non-water non1.000 SG didn't seem like it would add the 0.35 that it adds to a water 1.000.

But I'll certainly take the extra points

I noticed I used the same abv formula as you, except I used x135, whereas you use x131.25. Is there a consensus on which one is correct? I've read both.

When you say active fermentation, what do you mean? I mean, I've noticed that (1) restarted bubbling after those measurements, so I'd consider that active fermentation right? And what is the downfall of adding potassium sorbate to it while it's actively fermenting, except that it stops the fermentation... Which is kind of what I was going for.

Tbh, I'm really leaning towards letting it fully ferment, get two stable readings a week apart, and then stabilize and back sweeten. Although never read up on pasteurizing it instead, very interested in that now....


By the way thanks for insight, very helpful.

 

[CKuhns]

1 pound of honey in a total vilume of 1 gallon will always increase the SG .035 regardless of the gravity of the solution.

131.25 or 135 both can be used. I use 131.25 as the factor as it is the Mol Wt. Of alcohol produced and a constant for estimated amount of entrained CO2. I am not sure what the difference is between the two but have checked the ABV using 131.25 against a gas chromatograph in a lab and it matched pretty well.

Active ferment is just that a ferment that is still dropping your gravity at a brisk rate or showing lots of CO2 production. Both yours appear to not be too active so shouldn't be an issue. The downfall is if very active it will likely not inhibit the yeast.

 

[gkannon77]

Very helpful. I think I’m on the right track with my thinking so far. It’s cool you have access to a gas chromatograph. Haven’t seen one of those since grad school!

I guess what I was thinking is if you (hypothetically) added 1 lb of honey to a solution of 100% honey, to equal a total of one full gallon of all honey "must" (I know, bear with me), I wouldn’t expect the SG of the honey solution to change from before adding the 1 lb of honey to after adding the 1 lb honey, right? Because it's all the same honey, and so has the same specific gravity. (Quick google query show the SG of good honey is ~1.425). Using that logic I assumed that the specific gravity of sugary apple cider is probably similar to apple juice around 1.050. Since that’s 5% “denser” than water, I assumed adding 1 lb honey to something 5% denser would “thicken” it that much less... 5% less. So somewhere near 0.03325. I didn’t bother to do the math (until now) so in my earlier post I rounded down to 0.030.

But you are saying adding honey to ANY solution with any SG... will still add 0.035?

Trying to understand this better....

 

[gkannon77]

edit: double post

 

[CKuhns]

Agree honey to honey addition of the same type wouldnt change the SG as they are the same or nearly the same.

I dont know that i can answer the difference if starting with anything but a water or juice base. For me close enough is good enough.

I may check with one of the chemists I know.