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Need help finding out what my original gravity is after adjustments

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YOpassDAmike

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I ended up brewing an all grain batch yesterday and missed my predicted original gravity by a lot. My predicted gravity was 1.047, my actual original gravity was 1.022, I terribly missed my mark. In my carboy I had 3.75 gallons of 1.022 wort; therefore, I decided to bump up my gravity by adding dme and honey. I boiled 0.5 gallons of water and added 1lb of light dme and 21 oz by weight of honey. I got the gravity reading for my half gallon, which was 1.044. I added the half gallon batch to the carboy. Therefore, I know have 4.25 gallons in my carboy. How do i figure out my new original gravity after bumping it up with the half gallon batch? Thank you guys.
 
Ummm...something's either way off with your measurements, or way off with your gravity readings. 0.5 gallons with 1lb of DME alone (not including ~1.3 lbs of honey) should be WELL above 1.044. DME should be approximately 1.045 at 1 lb per ONE GALLON (give or take, depending on the specific extract manufacturer), and thus closer to 1.090 in 0.5 gallon. That amount of honey would almost double it again from there.

Are your gravity readings at the right temperature, or properly corrected? Please describe your process for taking readings...
 
I'm glad you asked, I have done about 7 all grain batches and I have never hit my predicted original gravity. In the past I would use a hydrometer but I just got a refractometer, which I used for this past batch. I made sure I calibratd my refractometer using distilled water. I also made sure my theremometer was calibrated, which it was (I used the ice water method). I got a water report from ward labs, therefore I adjust my water using gypsum and lactic acid to get appropriate ph level and mineral content for my mash. Mashing methods I have used are fly sparging and batch sparging. I used brew toad software for making recipes and used a water calculator for adjusting my water. I have a 10 gallon igloo cooler with a false bottom that I use for mashing (it always holds the appropriate temperature well).

Anyways brew toad said for a half gallon of water with 1lb of light dme added and 21 oz of honey added, my original gravity should be 1.057, which seemed low in my eyes. Both refractometer reading I took at 70*F. I do not know how I got such a low gravity.

However, would you know how to find the gravity.

3.75 gallons of 1.022 + 0.5 gallons of 1.044= 4.25 gallons at 1.0?? (what gravity).

Thanks for all the help.
 
I'm glad you asked, I have done about 7 all grain batches and I have never hit my predicted original gravity. In the past I would use a hydrometer but I just got a refractometer, which I used for this past batch. I made sure I calibratd my refractometer using distilled water. I also made sure my theremometer was calibrated, which it was (I used the ice water method). I got a water report from ward labs, therefore I adjust my water using gypsum and lactic acid to get appropriate ph level and mineral content for my mash. Mashing methods I have used are fly sparging and batch sparging. I used brew toad software for making recipes and used a water calculator for adjusting my water. I have a 10 gallon igloo cooler with a false bottom that I use for mashing (it always holds the appropriate temperature well).

Anyways brew toad said for a half gallon of water with 1lb of light dme added and 21 oz of honey added, my original gravity should be 1.057, which seemed low in my eyes. Both refractometer reading I took at 70*F. I do not know how I got such a low gravity.

However, would you know how to find the gravity.

3.75 gallons of 1.022 + 0.5 gallons of 1.044= 4.25 gallons at 1.0?? (what gravity).

Thanks for all the help.
 
Well, either Brew Toad got the addition wrong somehow, or it was input incorrectly. 0.5 gallons w/ 1 lb DME and 21 oz honey comes out to 1.194 (just entered it in Brew Toad myself) which is far more accurate.

Are you by chance reading in Brix and not in SG on your refractometer? Because 44 Brix isn't too far from 1.194
 
And your batch, was that by chance a 5 gallon batch? Because 3.75 gallons at 22 Brix works out to 16.5 Brix at 5 gallons, and Brix is *roughly* 1/4 SG, leading to ~1.066, much more where you should have been.

I ask, because many refractometers are Brix only, and not SG (and even the dual scale ones, the SG is often incorrect).
 
However, would you know how to find the gravity.

3.75 gallons of 1.022 + 0.5 gallons of 1.044= 4.25 gallons at 1.0?? (what gravity)..

Well this math is easy to do:
3.75 x 22 = 82.5 gravity pts
0.5 x 44 = 22 gravity pts

82.5 + 22 = 104.5 pts, in 4.25 gals that is 1.025 approx

But I'm with Qhrumphf your measurements look off. The 0.5 gal with 1 lb of DME will be 1.090 as mentioned. The 21 oz of honey you have to remember also adds volume, a quick search looks like that 1.31 lbs of honey at 1.035 contributes 14 fluid oz (.11 gal)

If you actually trust your initial 1.022 reading it's:
22 x 3.75 +
90 x 0.5 +
35 x 1.31 = 173 pts total, in 4.36 gal = 1.040

(edited - corrected addition of honey)
 
Well this upsets me, I reentered the 1lb of dme and 21 oz of honey for a volume of 0.5 gallons and I got a predicted gravity of 1.194. Yesterday, when I entered the same information, I got 1.057. Luckly I actually saved what I input for the half gallon batch and I just reopened the recipe and it is totally something different that I did not create. This recipe includes malt that I have never heard of and this unknow recipe has an original gravity of 1.057. Brew toad inaccurately input a random recipe for me. This is actually the second time brew toad did this to me, I once created a recipe but was unable to save it because I was not a pro member at the time and had limited save space; therefore, I wrote my recipe on a piece of paper. I later became a pro memeber and inputted the same recipe in brew toad and the ibu, abv, and other readings were different from the first time I inputted the same recipe. Is brew toad reliable, so far from my experience, brew toad seems very inconsistent to me.

Anyways my refractometer only reads in brix. The line on the scale was the first tiny line right above 11 brix. If my refractometer was calibrated and I tested my sample at an appropriate temperature, why did I not get a higher gravity reading?
 
I liked Hopville in years past, before I moved on to better software. Once I moved on, I still input stuff on there for free cloud storage. However, once Hopville migrated to Brew Toad, I was so disgusted with it and its clunky awkward functionality that I stopped using it altogether. So, my personal opinion here, but no, Brew Toad is not reliable. There's some great free programs out there (I know a lot like BrewTarget or the Brewer's Friend website), but I'm partial to BeerSmith (that one costs money though, but entirely worth it once you get past the learning curve).

My best suggestion would be to actually try a different calibration of your refractometer. Brix is a measure of w/w% dissolved sucrose, if I recall correctly. If you dissolve 1 gram of table sugar into 9 grams (should be 9ml) of distilled water, I that should equate to 10 Brix. I would calibrate your refractometer in distilled water first, and then use the sucrose solution as see if it lines up. You may have a bad refractometer.

There's got to be something wrong with your measurements, whether that's weight of fermentables, or volumes, or something. I'd suggest stratification, but that shouldn't be enough to cause the differential that you're seeing. There is absolutely no way that your DME/honey solution was only 11 Brix unless either there was a lot less added, or the volume was a lot more.
 
I want to thank everyone for their responses, they were all informative and very helpful. I will try the sugar with distilled water method to test the accuracy of my refractometer. I will be upgrading to beer smith in the near future. I thought only 11 brix was odd, when I was mixing the half gallon solution, it appeared similar to a thin syrup (very sugary). Quick question though, primary fermentation of this batch had already started, is there anyway now to estimate, test, or guess what my original gravity was, or is there a device to directly measure abv of a solution? For bottling carbonating, I would like to know roughly what my alochol percentage is, thanks again.
 
Were this an entirely extract batch, you can predict the OG with enough accuracy that there's really no point is measuring it. However, since your starting beer was all grain, where it's indeed possible to have poor enough efficiency for a low gravity, it's hard to say. @chickypad already did that math for you if we assume your 1.022 @ 3.5 gallons was accurate. The wrench, however, is that I highly suspect that your gravity readings are off for some reason, and that your OG was probably higher than that. Either that, or Brew Toad screwed up an overestimated the recipe, which is also possible.

To get a better idea, will need full grain bill, and post-boil volume (if different than your 3.5 gallons, not sure if any additional was left behind with hops/trub in the kettle).
 
At this point, I recommend you just relax and drink the results. There's always next time to dial in your process and hit your targets.. But for now, just drink some beer.
 
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