View Full Version : Forgot To Measure Initial Specific Gravity!

10-24-2009, 01:48 PM
I started my first batch of mead 6 days ago and completely forgot to take the inital specific gravity reading. I'm pretty new to this whole thing...is there any way to start my readings now and make any use of it all with no baseline to compare to?

10-24-2009, 02:05 PM
You can get an estimate of your OG by using your recipe. And yes, tracking the SG now is still very useful.

10-24-2009, 02:14 PM
My original recipe is as follows:
12 lbs of orange blossom honey
4.5 gallons of water
2 packets of d-47 lalvin yeast
yeast nutrient (not sure what exactly, the homebrew store lady said it was the right stuff)
4-5 sliced pears
2 slitted vanilla beans.

How do I go about estimating my OG based on that?

I went to go take a SG reading just now, and cannot find my hydrometer anywhere. I guess I will go get a new one and take it tonight.

10-24-2009, 03:02 PM
Check out the mead calculator (linked from the main page). There are instructions for use there and many, many threads on the forum about it. By entering the ingredients you used, it will estimate the OG. The pears will probably have a negligible effect so you could leave those out for a first approximation. Be sure to enter the total volume for the "volume" slot, not the volume of water you used.

10-24-2009, 08:12 PM
Thanks so much for your advice thus far...it really means a lot, you taking the time to reply.

My meads current stats are this: temperature is an even 65 degrees f. Current specific gravity appears to be 1.080. Current aroma and taste is very sweet. It's been on since the afternoon of Sunday 10/18/09. All is bubbling nicely.

I went to the mead calulator, but couldn't seem to find the box that tells me the OG. I may have a learning disability. :icon_blackeye:

10-24-2009, 08:58 PM
Bottom left corner. ;)

10-24-2009, 09:17 PM
So then if I did it right, at current 1.080 SG and 65 dgrees f, 12lbs of honey, and a target volume of 5 gallons, I would have had an OG of 1.168?

10-25-2009, 12:19 AM
I'm guessing you entered in your current gravity at the top, that serves a different purpose, like to figure out how much of one ingredient to add to get what you have to a specific gravity, or to figure out what sg the stuff you just added will take you to. In this case you told it you added 12lbs of honey to your must with 1.080 SG. Its ok, it took me a bit to figure out how to use it, the instructions in the newbie guide don't go over the more "advanced" uses of the calculator.

What you want to do for this is check the 1st "additional sugars" box, put in your amount, then check the "target volume" box enter your total volume. And click "calculate" if it hasn't automatically done it.

At five gallons(thats what you put in right?) with honey only should be in the ballpark of 1.088, but honeys are all different and don't necessarily have that same 79.6% sugar across the boad, you can however get a good number with a refractometer that reads up to 90% sucrose, but thats a different subject entirely.

With the small amount of pears you added, they wont change it very much, i figure 4 or 5 pears will run aroun 1-2 lbs depending on the size of the pears, so 1.089-1.090. As with the honey there are minor variables, but for these purposes I doubt that the actual starting gravity was more than 1.093, unless the honey was over 83% sugar.

You batch seems to be going pretty slow. Find out what kind of nutrient you bought, that could shed some light on why its going slow.

10-25-2009, 12:29 AM
Yes, sounds like you calculated an addition of 12lb of honey into your current must. Leave the 1.000 on the top for additions of honey into water (like an initial must).

12 lb of honey is roughly one gallon, so I'm guessing your total volume is around 5.5 gallons? This calculates to 1.080.

Good news is that if it is bubbling, it is fermenting. The gas in solution will stick to your hydrometer and lift it up, so be sure to degas your sample (spinning the hydrometer will dislodge the bubbles stuck to it) before taking a reading.

Some questions about your process:
Did you rehydrate the yeast? How?
Did you aerate your must? When?
How much yeast nutrient did you use?

Chances are good the next advice will be to aerate your mead and add some more nutrients.

10-25-2009, 12:52 PM
Yes, 5.5 gallons is about right, give or take.

I removed the airlock about 24 hours after airlocking the initial must and stirred vigorously. I did this again yesterday (6 days into primary fermentation). Am I correct that this is what is meant by aeration?

I put the yeast in a warm bowl of water for about 15 minutes prior to pitching. I also used "yeast nutrient" that the homebrew shop owner sold me, in a little baggie without much in the way of description.

The whole SG/OG/FG thing is really not clicking in my brain. I'm just not getting what I should expect, etc. etc. I am beginning to think I am not bright enough to be brewing, and that makes me sad. :(

10-25-2009, 01:36 PM
Oh, I'm sure you're bright enough, Joe, never fear. After all I manage to do it, and if I can, you surely can.

It does seem confusing at first, which is why I recommend (in all my newbeeness) to read through the Newbee Guide a couple of times before you get started, but in short, the OG is the original gravity, before you pitch the yeast. You really need that so you know how your mead is progressing, as it drops as sugar is converted to alcohol (which is less dense). You need to pay attention to the gravity as the days pass, because you're looking for the 1/3 sugar break (when one third of the sugar has been converted to alcohol) and the 2/3 sugar break (yep, when two thirds of the sugar has been converted to alcohol) to monitor the fermentation process.

You calculate those breaks by taking the amount of sugar over 1 (in a 1.100 must that would be 100) and divide it by 3 (which would make the 1/3 break at around 33 and the 2/3 break around 66). The problem with not doing the OG is that you can't easily calculate those breaks otherwise (Aaron's trick with the scale notwithstanding) and since they tell you when to stir and feed, they're rather important.

Generally you aerate only to the 1/3 break, and depending on what kind of a must you have going you feed at least then, and probably at the 2/3 break as well.

SG just stands for Specific Gravity, which is a ratio of the density of the must when compared to water. FG is the ending gravity, which can be pretty well predicted by plugging the sugars into the mead calculator, but you can measure it with the hydrometer too. It's fun to see how close you get to your calculations, and once you have the OG and the FG to put the numbers into this calculator (http://www.grapestompers.com/calculations.htm) to see what your ABV is. :)

But another piece of advice I can give you that served me well was to read MANY recipes similar to the one I was thinking of trying. That has kept me from screwing up too too badly and I haven't mucked any batch up too badly to drink. Yet. I don't think.

10-25-2009, 01:56 PM
How much nutrient did you use? Most instructions on nutrient packages are geared towards wine musts, not honey musts, so if you follow the directions you are still underfeeding your yeast.

What does the nutrient powder look like? Brownish fine dust or larger white crystals? Some of both? You'll probably need 10-20 g of nutrient (at least) to get the nitrogen content high enough.