OG and FG values are off from Beersmith values

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msa8967

mickaweapon
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My last four brews have all had OG values that have been higher than what is predicted by beersmith and FG gravity values lower that what was predicted. These have been recipes with predicted OG in the 1.054 range but actual OG of 1.060. Final predicted FG of 1.014 and actual of 1.010.

I have let the beers go in the primary for 4 weeks and then cold crash for 48 hours and then use gelatin for extra clarity. Could the presence of the gelatin change the FG this much? Not so sure if it is my crush by my barley crusher on the all grain recipes or something else for the higher OG numbers.

Any ideas and should I be concerned at all with these numbers being off?

Thanks.
 
They look close enough that I wouldn't lose sleep over it. Are your numbers consistently off by about .004 over multiple batches? Most importantly, how is the beer?
 
I doubt gelatin will do anything to affect the fg. I'd be willing to bet that the numbers are off due to the readings, temperature adjustment for the reading, etc. That is a minimal difference and I wouldn't worry about it. The calculators/software take an average og for each grain, lme, etc and yours may vary a bit. RDWHAHB.
 
Sounds like you're getting better efficiency than the beersmith default of 75% and that you're using a highly attenuative yeast. What yeast are you using and what temp are you mashing at?
 
I would echo about the temperature adjustment. I also might say maybe you are mashing too low. A low mash temp will cause better attenuation, but a thinner body on the beer.
 
Contrary to how it appears, Beersmith doesn't really predict your FG. OG, yes. But not the FG. The reason is that it just gives you a 75% flat attenuation figure, regardless of yeast strain and ingredients and/or mash temperature! So, the projected FG is actually a useless bit of the software that I wish was fixed. You'll have to guestimate your FG yourself based on ingredients, yeast strain, mash temp, etc. We can definitely help you with that, so you don't have to do it alone.

As far as the OG, if it's an extract batch it's impossible for the OG to be off, unless your volume is off. What I mean is that there is a set amount of sugars in the extract, and unless you don't use all the ingredients, or you add too much water, it's impossible to miss the OG. It's impossible to "lose" those sugars. But if the recipe is for a 5 gallon batch, and you fill the fermenter 5.5 gallons total, the OG will be lower.

Sometimes false OG readings happen when people do a partial boil and then top up with water. It's very difficult to mix the water with the wort so that it's equalized throughout, and it's very common to get an inaccurate reading. That's fine, as it doesn't really matter since the OG has to be what the ingredients add up to.

If you're doing all grain, the key is to just adjust the efficiency % to YOUR efficiency, and then the numbers will match.

Hope this helps!
 
I have been getting OG numbers that have been too high for the last four brews based on 75% eff via beersmith. I have been using single infusion batch sparging option which has mash temp of 154 F. However, my mash tun (even wrapped with blankets) has its temp drop to under 148 F by the end of the 1 hour mash period. I would prefer to have a fuller body beer (something not so thin) so it sounds like raising the mash temp to around 156 might be in order.

As far as yeast goes I have been using Wyeast 1056 with a starter made. All of these batches have been all grain and I use the temp adjustment option on beersmith to read the gravity numbers. I might move my mashtun indoors for the next two brews because outside temps are in the single digits and I have to brew in the garage or face the wrath of swmbo for taking over the kitchen.
 
I have been getting OG numbers that have been too high for the last four brews based on 75% eff via beersmith. I have been using single infusion batch sparging option which has mash temp of 154 F. However, my mash tun (even wrapped with blankets) has its temp drop to under 148 F by the end of the 1 hour mash period. I would prefer to have a fuller body beer (something not so thin) so it sounds like raising the mash temp to around 156 might be in order.

As far as yeast goes I have been using Wyeast 1056 with a starter made. All of these batches have been all grain and I use the temp adjustment option on beersmith to read the gravity numbers. I might move my mashtun indoors for the next two brews because outside temps are in the single digits and I have to brew in the garage or face the wrath of swmbo for taking over the kitchen.

Just changing the efficiency % until you hit the number you actually got will work. It'll also change the IBU/SG ratio and the IBUs for you, so it's a simple fix. If you're consistently getting 80%, just change that in Beersmith and the accuracy will be fine.

Do you preheat the MLT well before the mash? I put about two gallons fo 180 degree water in mine (I have an Igloo cooler that can take it, without warping- but water hotter than that warps it, as I found out!) and let it sit for at least 20 minutes. By then, the liquid is under 165 degrees in the cooler so I have to add more hot water to get to my strike temperature. Preheating well, as well as wrapping with blankets/sleeping bags might really help.

If you've tried that and it's still dropping that much, you're going to have to mash inside, but maybe figure out a way to only keep the MLT inside and do everything else outside. Maybe a wagon, to haul a full MLT? I can barely lift an MLT with just the grains let alone all the water in it!
 
If you've tried that and it's still dropping that much, you're going to have to mash inside, but maybe figure out a way to only keep the MLT inside and do everything else outside. Maybe a wagon, to haul a full MLT? I can barely lift an MLT with just the grains let alone all the water in it!

This is similar to what I've been doing since it started getting cold. This is my first winter as an all grain, outdoor brewer, so figuring out ways to keep from freezing my ass off while brewing has been fun. I heat my strike and sparge water on my electric stove, mash in my kitchen and then do the boil outside. Not only does this save propane, but I stay nice and toasty and only have to quickly run outside for my hop additions.
 
Have you calibrated your hydrometer? Mine is off by 4 points. Your data is not entirely consistent with this theory (OG is higher and FG is lower). But maybe you are making very fermentable wort.
 
I mash in an Igloo Ice Cube cooler, one of the first things I did was to cover the top of the lid with masking tape and drill several holes in the hollow lid from the top, I then shot "Great Stuff" expanding foam into the lid to insulate it, the excess foam oozes out of the holes and onto the tape. when dry it is pretty easy to lift off the tape and do some finish trimming to the foam at the holes, you wont have the messy foam all over your lid, and it will hold heat much better! wrap that in blankets and you should be holding temp much better!
 
I have calibrated two hydrometers and used both to obtain virtually the same readings. I do preheat my mash tun with the strike water set to be about 5-8 F over what beersmith calculates to use and let the temp fall until it gets to 165 F and then add the grain and stir.

Most people would probably like having a higher ABV% but it does reduce the IBU/SG ratio and I would prefer more body and perhaps less alcohol. I am brewing today and have moved the mash tun indoors and will wrap with a blanket to see if it holds the temp better.
 
I have calibrated two hydrometers and used both to obtain virtually the same readings. I do preheat my mash tun with the strike water set to be about 5-8 F over what beersmith calculates to use and let the temp fall until it gets to 165 F and then add the grain and stir.

Most people would probably like having a higher ABV% but it does reduce the IBU/SG ratio and I would prefer more body and perhaps less alcohol. I am brewing today and have moved the mash tun indoors and will wrap with a blanket to see if it holds the temp better.

I'd try again with the preheating, but way more than 5 degrees above strike temp. Like I said, even in my indoor (but cool) brewery, I have to use 180 degree water to preheat my cooler. It drops 15 degrees very quickly. But then, after about 15 minutes, it doesn't lose any more heat so I add the rest of my strike water at the correct temperature and then mash in.
 
I took your advice mentioned earlier for the batch going on right now. I preheated the mash tun with 1 gallon of water at 185 F and then shut the lid for 15 minutes and then emptied the cooler. Next I added my 3 gallons of strike water at 180 and it took about another 10 minutes for this to fall to the proper temp of 170 F prior to adding the crushed grain. I have the mash tun moved indoors and covered with both a wool blanket and a heavy parka. After 60 minutes I opened the mash tun and the temp was still at 145 F (instead of the desired 154 F). This is the same result I have got when I had been brewing outdoors with air temps in the upper 40's.

Guess it might be time to build a new mash tun using a new cooler instead of $4 garage sale one I tried when I started all grain.
 
I took your advice mentioned earlier for the batch going on right now. I preheated the mash tun with 1 gallon of water at 185 F and then shut the lid for 15 minutes and then emptied the cooler. Next I added my 3 gallons of strike water at 180 and it took about another 10 minutes for this to fall to the proper temp of 170 F prior to adding the crushed grain. I have the mash tun moved indoors and covered with both a wool blanket and a heavy parka. After 60 minutes I opened the mash tun and the temp was still at 145 F (instead of the desired 154 F). This is the same result I have got when I had been brewing outdoors with air temps in the upper 40's.

Guess it might be time to build a new mash tun using a new cooler instead of $4 garage sale one I tried when I started all grain.

Or move to a warmer climate! :D

I tell you, I love brewing indoors. The only time I think it would be better outdoors are those few days when it's 75 degrees with a light breeze. Otherwise, I'm happy as can be inside!
 
My wife and I had our first baby 7 months ago and decided to move to a bigger house. Unfortunately the "new" house has an electric stove top that can't boil much more than 2-3 gallons on the largest burner. We had a gas stove in the previous home and that was great to do all grain with. I could get batches done indoors then. Now I am subject to using a turkey fryer outdoors and limited to one batch per day.

I might try to run a natural gas line to the kitchen next spring and replace the stove we currently use with a gas stove so I can do these indoors.

Thanks everyone for your comments and advice.
 
Or move to a warmer climate! :D

I tell you, I love brewing indoors. The only time I think it would be better outdoors are those few days when it's 75 degrees with a light breeze. Otherwise, I'm happy as can be inside!

The warm weather locale is a whole different set of issues to deal with, I insulated my cooler lid because if I was mashing out back in the summer I would have issues with the mash temp RISING by several degrees, I have documented the temp inside my car here in the summer to be 270°, same type of heat transfer goes on in a mash tun!, you also have the dilemma of trying to chill your wort, not an easy task when your cold tap water is an average of 100.3°. I do agree that I love brewing outside when it is 75° with a light breeze, I brewed 10 gallons of English mild last weekend in those conditions! :D
 
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