View Full Version : ABV/yeast questions

08-28-2008, 08:44 AM
To begin, here's my recipe:
- 21 pounds of clover honey
- 10g Lalvin 71B
- Enough distilled water to top to 6 gallons

Process - Batch created August 2nd, 2008 <American Homebrewers Association Mead Day>:
- I chose to pasteurize the must at 160 degrees for 10 minute (instead of boiling)
- Cooled in 7.9 gallon wine bucket set in a larger bucket filled with ice. Still took a consderable time to cool to pitching temp (time for a wort chiller I think)
- Transferred cooled must to 6-gallon glass carboy prior to pitching yeast
- Rehydrated the yeast with 12.5g of GO-FERM @ 102 degrees distilled water and pitched
- I followed the staggered nutrient plan per Hightest's site:
- At inoculation - 4.5g Superfood [or Fermaid-K] & 4.5g DAP
- At active fermentation - 2.8g Superfood [or Fermaid-K] & 2.8g DAP
- Just before fermentation mid-point - 1.8g Superfood [or Fermaid-K] & 1.8g DAP

- Before pitching the rehydrated yeast, and adjusting OG for temperature (around 80 degrees) OG reading was 1.136. That seemed high, but I wanted a sweet mead so I was not complaining.
- Fermentation was going full-bore by the time I woke up 8 hours later. The staggered approach apparently works well. Or maybe the 71B was just more responsive. Either way - this was the most vigorous fermentation I had seen since the cyser I made last year. In comparison, I have used liquid White Labs Mead Yeast and it was definitely a slow starter and took 2 days before fermentation began. Anyways -

There seems to be alot of differing opinions on the amount of time to leave in the primary. I think I had read not to leave on the lees for too long when using 71B. Bubbles had also slowed considerably - about every 45 seconds. With that in mind, I decided to rack to secondary last night August 27, 2008. I took a finished gravity reading and it was 1.015! Wow, I wasn't expecting it to be that low. My questions are:

- With those gravities - is the ABV really around 18%? Using brewcalcs.com, the ABV result is 18.4% - wow, that's high.
- Can 71B reach that ABV? I've read 14% was the max
- Did it have to do with using 2 packages (10g) instead of just 1 package of 71B?
- If so, do you think the staggered nutrient approach had anything to do with these results?
- I had covered the carboy and put in a cool spot in the house so I don't think it ever got warmer than 72-74 degrees in my house...

I wasn't expecting this end result. I racked in to 4, 2-gallon buckets with 1.5lbs of mangos, 1.5lbs of blackberries, 1.5lbs of strawberries and 1.5 pounds of blueberries. I jsut hope it doesn't end up "too hot".

Medsen Fey
08-28-2008, 09:50 AM
I'm not sure how that ABV calculation was done, but if you follow the formula outlined Here (http://recipes.howstuffworks.com/question532.htm) the result is about 15.5% ABV.

71B, if it is rehydrated properly and well nourished, can definitely hit the 15% range. And yes, the staggered nutrients help yeast to reach their maximal alcohol tolerance. Using more yeast will not increase their tolerance for alcohol.

Will it taste hot? That depends on your palate. Everything I taste with alcohol above about 14% tastes hot to me, but I'm a light-weight. With your temps in the low 70s you may have some fusels adding to the perceived "hotness." If it does seem hot to you, my advice is to give it plenty of time to age - that will allow it to mellow and smooth out which usually reduces the alcohol sensation.

Having it sweet helps mask the "hotness". Also the fruit flavors (and sugars) may also blend in to prevent the perception of "hotness."

You have heard correctly that leaving the mead on the lees with 71B will give off flavors, so it is good to rack it early.

It sounds like you should have several batches of very tasty mead!



08-28-2008, 02:07 PM
Thanks for your input Medsen Fey,

I used the http://brewcalcs.com site to get ABV. I think I'll use that link you included for the ABV calculations because obviously there is something different in their formula. I can live with 15.5%. Is there some variable that they may have used that is beer specific do you think?

08-28-2008, 02:50 PM
Hey, Fishbone! Let me jump in here to say that according to my calculations, your original SG should have been more like 1.124. This is based on an "average" honey SG of 1.417 and your statement that you topped up to 6 gallons with plain water. I'm thinking that you may have not had your honey completely dissolved in the must, and that could have given you an artificially high SG reading.

When I find discrepancies in brewing calculation tools, I always double check with this equation: S1*V1 + S2*V2 = St*Vt where S1 is the SG of ingredient 1, V1 is the volume of that ingredient, S2 is the SG of ingredient 2, V2 is its volume, and St and Vt are the SG and volume, respectively, of the mixed result.

Assuming S1 and V1 are the SG and volume of your honey (1.417 and 1.78 gal), S2 and V2 are the water addition (1.000 and 4.22 gal), and the results are St and Vt (with Vt = 6.0 gal in this case), solving the equation for St yields: (1.417*1.78 + 1.000*4.22)/6.0 = 1.124.

So, with a final gravity of 1.015, the Brew Calcs tool says your ABV is 16.3% but my calculation indicates an ABV of 14.4%. If the brew had actually fermented to dryness (1.000), then the ABV would have been 16.3%. I can't see the formula used for ABV calculation in the Brew Calcs tool, but I believe that there are some biases in there that are drawn from assumptions about the percentage of fermentable sugar to total dissolved solids when measuring your original gravity -- those are OK approximations for beer, but are not valid for meads since honey sugars are 100% fermentable. Even with those assumptions accounted for, I don't think that the Brew Calcs tool is correct. Well, you do somewhat get what you pay for on the internet! ;)

08-28-2008, 03:35 PM
I created a spreadsheet using the formulas from your link. I also did some research and found quite a few alternate formulas for computing ABW and ABV. When using these formulas with my OGs and FG, none of them broke 16% so I assume that the brewcalcs.com calculations are incorrect. Needless to say, I will not be using that site again. Including the formula in your link and formulas that I found elsewhere, averaging the results of what look like 3 reliable methods results is about 15.6% for the mead that I racked last night. I can live with that. Like you said - even if it was hot, the fruit that I racked it on to and aging should do the trick...but it looks like I have nothing to worry about now.

Wayneb, thanks for that other formula - another thing to put into my bag of tricks.

08-28-2008, 03:51 PM
OK dude, looks like some great advice from Medsen and WayneB below.

Here's some recipe advice from me.

1. Distilled water has been stripped of everything so you'll need to really aerate/oxygenate before, during and after you pitch your yeast. Also there are other minerals that help to add to the vigor of the fermentation. It's always a good idea to get an info pamphlet from your local city/county seat about water quality and content in your area. If a standard water filter isn't going to make your water palatable then it's time for bottled water. Rather than distilled water, get spring water (taste before using obviously) and use the spring water. The distillation process also affects the O2 level in the water which is why you have to work extra hard to aerate.

2. Heating your honey. Not necessary, not the best way to treat your honey and adds unnecessary time to the mead making process. There is no need to heat your honey from a sanitization standpoint. I see below that you used brewcalcs.com (well address that one next) so my guess is that you're coming at this from a brewing perspective rather than a mead or wine-making perspective. Honey is inherently bacteriostatic and will only ferment when diluted to such a gravity that yeast, bacteria, etc. may begin to divide and grow. Sanitizing the honey is unnecessary not only because of this, but because the yeast you are pitching into the must are designed to outcompete other organisms especially other yeast. Some yeast produce a competitive factor (mitochondrial protien) that actually kills off other sensitive yeasts by interrupting the magnesium processing in the target yeast cells. This protein disrupts the magnesium metabolism which in turn causes the death of the cell.

Heating also denatures or outright destroys fermentation friendly proteins and enzymes that are present in the honey. Most importantly though, heating cooks off desirable floral and varietal aromas, flavors and characters that would not be lost if the honey was not heated. I look at it this way, the honey I buy is expensive and I'm paying for the things that makes the honey unique and desirable. I don't want to alter the character, aroma or flavor of the honey before I even begin fermentation. I want all of those components to be present in the mead in their newly fermented forms. Finally, from a winemaking perspective, I don't heat my grape must before I pitch my yeast, it would alter the flavor of the finished product (not for the better in my opinion having tried it) and really do a disservice to the time, money, labor and selection regimen spent on picking out the grapes I use to make my wines.

3. Using brew calculators for meadmaking. PUNT! 'Nuff said. Use Wayne's formulae below, and go here (http://www.gotmead.com/Making-Mead/Mead-Making-Calculator.html) to use the Got Mead mead calculator.

Hope this helps,


08-28-2008, 09:01 PM
One thing I forgot to mention in the process that I followed is aeration - I used a lees stirrer for 10 minutes at pitching, then aerated again at each nutrient addition per Ken Schramm's (slightly different than Hightests') stepped nutrient approach. It foamed like crazy and I lost a little mead on that second aeration because of the foam, but I think worked.

I never considered the loss of O2 indistilled water lacks, but thanks Oskaar - now I know - spring water it will be. I think I will take your advice on heating as well - in the least, it will shorten the time considerably. So far, I haven't splurged on expensive varietal honies. It's been mostly clover and wildflower. When I do break the bank open and by some raspberry honey, it will definitely not be heated.

Which brings up another question...how do you mix the honey and water to ensure it's thoroughly mixed? Spoon and good ol' muscle power or would the lees stirrer do the trick?

08-29-2008, 12:22 AM
Once you get the honey at least partly liquified in the must, then your lees stirrer does double duty -- helping you to get the must completely mixed, if you raise it a bit and tilt it right, you'll aerate the batch, too!