Hosed up my FG by.....

[jarrod521]

....getting the bright idea to keep my mash temperature up. So here's what I did. I noticed the top of the kettle was 125 degrees but the bottom was 155. So I got the bright idea 30 minutes into my mash to take some of that 155 degree water from the bottom, open up my kettle valve, drain about a gallon off, and pour it on the top. Did this a couple times 30 minutes in to my 60 minute mash. My FG was supposed to be 1.064. It was 1.034.

Did I basically do a mashout at the 30-minute mark and stop extracting fermentable sugars?

Thanks in advance for the responses--I'm new at this and am learning a lot through this forum.

 

[porterpounder]

155 is not high enough to stop enzyme activity, i.e. a mashout step. That is a huge stratification difference in temps. Any areas hovering below 135-140 are not likely to convert due to lack of beta activity. Next time try insulating your mash tun better and if you see a discrepancy like that stir the mash, take a more uniform temp reading and add boiling water if needed, stir and continue until you are up to your desired temp.

 

[jarrod521]

Thank you!

Live and learn, I suppose. We'll see what it tastes like in 6 weeks.

Again, thanks for taking the time to share and have a good weekend!

 

[kh54s10]

I agree that the temperature was not enough to have any chance of stopping enzyme activity. Have you been hitting your target OG? If so, what other changes might have been made. Grain crush is usually the first place to look for low OG performance.

 

[TexasWine]

....getting the bright idea to keep my mash temperature up. So here's what I did. I noticed the top of the kettle was 125 degrees but the bottom was 155. So I got the bright idea 30 minutes into my mash to take some of that 155 degree water from the bottom, open up my kettle valve, drain about a gallon off, and pour it on the top. Did this a couple times 30 minutes in to my 60 minute mash. My FG was supposed to be 1.064. It was 1.034.

Did I basically do a mashout at the 30-minute mark and stop extracting fermentable sugars?

Thanks in advance for the responses--I'm new at this and am learning a lot through this forum.

Are you confusing final gravity (FG), which is after fermentation, and original gravity (OG), which is before fermentation? What you did was essentially a mid mash Vorlauf. Without an external heat source, if you're sitting at 155°F max temp there would be no way for this to stop enzymatic activity.

So I think what you're asking is why was your OG so low? And without more information, no one will be able to tell you why. What was your grain bill along with volume measurements and gravity readings at various steps, like during the mash, pre and post boil.

Hope this helps.

 

[jarrod521]

Good catch--my *OG* is 1.034.

This is my third BIAB. After reviewing my brew notes, here are some errors I see.

1) I have one more gallon of water in the kettle than the recipe calls for.

2) I could only fit 10 of the 12 pounds of grain in the bag, and it was packed in pretty tight. Grain bill was 11 lbs of two row and 1 pound of Caramel 40.

3) Refractometer reading at the 30 minute mark when I got creative was 1.034--it never got any higher.

Thank you all for helping me learn. Clearly, I'm a beginner.

 

[wilserbrewer]

Ideally your grain bag should be large enough to line the entire inside of the kettle, and fold over the top rim of the kettle, resulting in the full volume of the mash to be inside the bag. This way when you stir the mash, the temp will be even throughout.

If your grain was packet tightly in a small bag, that may likely be a problem???

 

[jarrod521]

Thanks, wilserbrewer. I'll ask the Mrs. to make me a larger bag and I'll try again. There was zero room to stir.

 

[Yooper]

Thanks, wilserbrewer. I'll ask the Mrs. to make me a larger bag and I'll try again. There was zero room to stir.

Make sure that the grain is very loose in the bag, almost like no bag at all. The only use for the bag is to remove the grain from the wort once the mash is over, and the grain and water need to be very fluid and stirred very very well. I'm sure that is why the OG is so low- if the grain was packed in and not in contact with the water.

 

[Sadu]

Yep that sounds like the problem. You need the water to be able to freely move around the grains. If most of the water is outside the bag then you aren't going to get good efficiency.

Also leaving out 2 pounds of grain is going to drop your OG by quite a bit. You might be better off brewing a smaller beer (1.040 - 1.050 OG) until you get these issues ironed out. I find even after 30 brews, that smaller beers are a lot easier to brew than bigger beers. And there's a huge range of insanely good-tasting beer in the 4-5% abv range.

 

[jarrod521]

Thanks to all--I have another carboy, so I'm going to try again Tuesday!

 

[atcsat]

Keep at it, Jarrod, BIAB is really a good way to brew. I'm continually working out the kinks and upping my game with each brew, as you will also!