Why does my beer always end up a couple points below BeerSmith Est. FG.

[anico4704]

Every time I brew, no matter what temp I mash at, I always end up with a FG like 5-6 points below what BeerSmith is estimating. Why could this be?

For example, just brewed a Scottish Ale and mashed at 157. After putting in all my numbers the estimated FG was 1.016. I ended up at 1.010. The beer before that was also around the 156-157 range mashed and had an estimated FG of 1.012 and ended at 1.007. Why would this be? I calibrated my hydro and thermometer. I can tell the beer is drier than it should be just by tasting it, but I don't know why they end up like this?

 

[KeyWestBrewing]

Are you using specialty grains? What yeast are you using? Been adding any honey or table sugar to your beers?
Personally I find Beersmith to be off when it comes to FG but mashing that high in your case shouldn't leave you that dry.

 

[gcdowd]

Mine is always a few points lower too. I just adjust my target down to compensate

 

[unionrdr]

I've only used it on a couple beers so far,but BS2 has been pretty accurate for OG/FG range on mine. But what confuses me is looking at the graph at the bottom of the recipe design page. On the left of the graph,for instance,it'll read Est Original gravity 1.057. On the right,it'll read 1.056-1.075 SG. Then,on the list to the right of that,it'll read Est final gravity 1.009. Measured OG 1.046,when actual was 1.060. Although I may've forgoten my 5 minute stir to mix them. I have been known to forget that part & have to go back & stir/test again.
And measured efficiency on this example reads 136% !? I set the profiles for;
Mash- BIAB,medium body
Carbonation-Corn sugar
Fermentation-Ale,single stage
This besides my profiles for whether it's AE or partial mash,what kettle used & all that. Even set my Est pre-boil volume at 3.5 gallons to accurately reflect what I get after mash & sparge. It does say Tot Efficiency 72%,Est mash Efficiency 76.8%,so that part's pretty good.
It's just the different gravities & "measured efficiency" that throw me a little.
And that's not even getting into how they say to brew it in their instructions.

 

[GASoline71]

Mine is always a few points lower too. I just adjust my target down to compensate

Me too...

I've been farting around with BS2 for about 6 months... still haven't got it nailed down to where I really want it. I need to figure out my efficiency and then I think I will be able to really nail down my numers.

Gary

 

[KeyWestBrewing]

Dialing in your efficiency and inputing all your equipment info really helps.

 

[rklinck]

I would triple check your thermometer. I can't imagine ending up with 1.010 FG mashing at 157 (I'm assuming that OG was somewhere around 1.050).

 

[ifnotuthenwho]

I've only used it on a couple beers so far,but BS2 has been pretty accurate for OG/FG range on mine. But what confuses me is looking at the graph at the bottom of the recipe design page. On the left of the graph,for instance,it'll read Est Original gravity 1.057. On the right,it'll read 1.056-1.075 SG. Then,on the list to the right of that,it'll read Est final gravity 1.009. Measured OG 1.046,when actual was 1.060. Although I may've forgoten my 5 minute stir to mix them. I have been known to forget that part & have to go back & stir/test again.
And measured efficiency on this example reads 136% !? I set the profiles for;
Mash- BIAB,medium body
Carbonation-Corn sugar
Fermentation-Ale,single stage
This besides my profiles for whether it's AE or partial mash,what kettle used & all that. Even set my Est pre-boil volume at 3.5 gallons to accurately reflect what I get after mash & sparge. It does say Tot Efficiency 72%,Est mash Efficiency 76.8%,so that part's pretty good.
It's just the different gravities & "measured efficiency" that throw me a little.
And that's not even getting into how they say to brew it in their instructions.

On BS2, the left side of the graph indicates what FG is expected based on the grain bill. The range on the right side of the graph indicates the acceptable values for the style of beer you have selected in the drop down box.

Regarding the measured OG, I think you are supposed to enter your actual value there, and then it will adjust some of the other calculations based on your input. But I'm not sure about that part because I've only used BS2 twice, and I've never entered my OG.

HTH

 

[rdkopp0153]

+1 on thermometer issues. The floater thermometers tend to read 4-6F higher than my lab grade thermometer. Meaning that if you are intending to mash at 157 F you could "actually" be mashing at 151 or 153 F, which would attenuate out more.

 

[unionrdr]

Thanks. I did enter my measured OG,but I don't think it changed much of the numbers,if any. I did do some set up on my kettle,boil volume,& all that. Might still need some tweaking?....but I'm sure all is closer now than it was. I've only done a couple recipes with BS2. There's a lot to set up & absorb it seems.

 

[anico4704]

I just recalibrated my thermometer last night and I will see how the next batch turns out with it this weekend. My profile and efficieny numbers are almost perfectly setup so I would think maybe it is my thermometer. I have been using some crystal malts in most of these brews and the fem temp has been on the low end range. Gotta be the thermometer

 

[anico4704]

And all different yeast american ale american ale ii scottish ale us05 the hef strain from wyeast forgot the name. No table sugars or other adjunct sugars

 

[rklinck]

And all different yeast american ale american ale ii scottish ale us05 the hef strain from wyeast forgot the name. No table sugars or other adjunct sugars

My experience has been that BeerSmith does a good job of accounting for things (e.g., different yeasts). So as long as you have your system dialed in and you are hitting your OG consistently, it has to be the thermometer.

 

[klnosaj]

I use BeerSmith for all of my calculations and I brew about once a week so I have some familiarity with it. I was having exactly the problem OP describes, but only intermittently. I know that a couple of the yeasts have had attenuation numbers that either didn't match those published by their manufacturers or that don't comport with practical experience. But it turns out that the primary chronic fault was with my thermometer. When I used a Taylor probe thermometer my FG was always too low, usually by about 4 points, which is insanely frustrating and can ruin a beer. When I use my thermapen my numbers usually come in right on target. Turns out that Taylor thermometer was reading several degrees too hot so when I thought I was mashing at 154 I was actually mashing at 150. Never mind what that difference would do to a steak, it totally f*%ks up the beer.

 

[anico4704]

Ill try out the newly calibrated thermometer in cold and boiling water and report back in 3 weeks with results of my fg from this coming weekends brew