All my FG's are high

[maltMonkey]

I've really learned a lot from this thread so far. I didn't just jump into AG, I read a couple books, did a lot of internet searching etc. Nothing I've seen so far would have lead me to believe that mashing at the high end of the range would affect attenuation so drastically. I mean, I've got around 50% attenuation (as of my last gravity check) on the two beers. That seems really low regardless of my mash.

This is also the first place where I've seen a 158° rest referred to as too high--all my other sources just have mentioned in passing that this is the range you want to mash in if you want a malty beer, which is what I like.....

I have no problems chalking these up to a learning experience---maybe they'll still be good, who knows?

 

[kenb]

I've really learned a lot from this thread so far. I didn't just jump into AG, I read a couple books, did a lot of internet searching etc. Nothing I've seen so far would have lead me to believe that mashing at the high end of the range would affect attenuation so drastically. I mean, I've got around 50% attenuation (as of my last gravity check) on the two beers. That seems really low regardless of my mash.

This is also the first place where I've seen a 158° rest referred to as too high--all my other sources just have mentioned in passing that this is the range you want to mash in if you want a malty beer, which is what I like.....

I have no problems chalking these up to a learning experience---maybe they'll still be good, who knows?

Try mashing at 150f. Then mash the same recipe at 159f....I bet you will see a final gravity difference of between 5-10%...

 

[Soulive]

This is also the first place where I've seen a 158° rest referred to as too high--all my other sources just have mentioned in passing that this is the range you want to mash in if you want a malty beer, which is what I like.....

I've never mashed that high. Even if I'm doing an English ale, I only go up to 156F. Its not horrible to mash that high, but it definitely is on the high end of mash temps...

 

[cefmel]

Here are all the things I can think of to improve fermentation.

1. Use the correct yeast pitch rates. About 200 billion yeast cells for a 5 gal batch of ale. This usually means using a yeast starter.

2. Oxygen. Use the air stone with pure oxygen before pitching the yeast.

3. Use Wyeast nutrient. It has all the trace elements like zinc, amino acids, minarals etc. that yeast need to be healthy. You can order it at northernbrewer.com.

 

[maltMonkey]

Well I checked the 2 beers again tonight. The amber dropped a couple points but looks to be sticking at 1.024. The brown hasn't moved. Screw it--I'm bottling it tonight.

More on the high gravities--I took a reading on my RIS that's been fermenting for 2 weeks.....OG was .1085. It's 1.034 -- about 60% attenuation (the yeast avg is 71%). I capped the carboy, shook the #&$* out of it and we'll see if it drops more.

On a happier note I've started mashing at 154° on my last 2 beers, and the hefe & APA are happily fermenting along -- I have higher hopes for them.

 

[kenb]

Well I checked the 2 beers again tonight. The amber dropped a couple points but looks to be sticking at 1.024. The brown hasn't moved. Screw it--I'm bottling it tonight.

More on the high gravities--I took a reading on my RIS that's been fermenting for 2 weeks.....OG was .1085. It's 1.034 -- about 60% attenuation (the yeast avg is 71%). I capped the carboy, shook the #&$* out of it and we'll see if it drops more.

On a happier note I've started mashing at 154° on my last 2 beers, and the hefe & APA are happily fermenting along -- I have higher hopes for them.

Keep in mind that 'shaking the hell' out of a carboy this late in the fermentation cycle is likely to cause oxidation issues..ie off flavors.

 

[Denny's Evil Concoctions]

I'm not sure if anyone aske dthis but do you use direct heat or infusion mash?

Direct heat is often hotter on the bottom even after you've turned off the flame than the first 10 inches of the mash (10g batcH. That 158 reading might actually be quite higer. Happened to me. I started using an elctronic probe and teh bottom temp was 163 and the top/mid layer was around 158.

Also what are you using for a thermometer?

 

[Bearcat Brewmeister]

Keep in mind that 'shaking the hell' out of a carboy this late in the fermentation cycle is likely to cause oxidation issues..ie off flavors.

Actually, the carboy should not contain any oxygen near the end of fermentation. CO2 is heavier than O2 and its release from the fermenting wort quickly pushes all of the oxygen out. IMHO, oxygen is not the issue. If it is a primary fermenter, I wouldn't want to stir up the trub late in fermentation.

158F is fine for a Scottish ale and maybe a English mild or Southern brown, but I don't go higher than 154F on anything else (and I like malty beers). I can't remember where I read it, but the middle of the attenuation range you read for a yeast is most accurate at 154F. For each degree change in mash temperature, the difference in FG is somewhere just under 0.001. I think I remember the study said that the experiment tested mashes of 154F and 160F, and a wort with SG of 1.050 ended at 0.005 higher than the wort that mashed at 154F. I have found this to be close, but since there are other factors at work, not exact.

 

[kenb]

Actually, the carboy should not contain any oxygen near the end of fermentation. CO2 is heavier than O2 and its release from the fermenting wort quickly pushes all of the oxygen out. IMHO, oxygen is not the issue. If it is a primary fermenter, I wouldn't want to stir up the trub late in fermentation.

Unless you take off the airlock and let oxygen back in before shaking the carboy. Something to think about anyways. Either way i wouldn't risk it...

 

[maltMonkey]

I'm not sure if anyone aske dthis but do you use direct heat or infusion mash?

Direct heat is often hotter on the bottom even after you've turned off the flame than the first 10 inches of the mash (10g batcH. That 158 reading might actually be quite higer. Happened to me. I started using an elctronic probe and teh bottom temp was 163 and the top/mid layer was around 158.

Also what are you using for a thermometer?

It was an infusion mash in a 60qt cooler - Here are the thermometers I use (One is installed in the MLT). I thought about the thermometers being off.....I might try calibrating them, or at least double checking with a different thermometer next time. Nice thought.

 

[maltMonkey]

Actually, the carboy should not contain any oxygen near the end of fermentation. CO2 is heavier than O2 and its release from the fermenting wort quickly pushes all of the oxygen out. IMHO, oxygen is not the issue. If it is a primary fermenter, I wouldn't want to stir up the trub late in fermentation.

I guess I'm just not worried about either scenario--when you shake a carboy like I did it immediately starts spitting out more CO2, so 3 minutes after you replug it all the oxygen is pushed out.....the trub will resettle pretty quickly, I'll leave it in primary for another week and then a couple weeks in secondary.....

 

[kenb]

I guess I'm just not worried about either scenario--when you shake a carboy like I did it immediately starts spitting out more CO2, so 3 minutes after you replug it all the oxygen is pushed out.....the trub will resettle pretty quickly, I'll leave it in primary for another week and then a couple weeks in secondary.....

Except the oxygen that you just dissolved into the beer via the shaking is NOT ALL pushed out . Trust me, i did it on my first few batches that were finished too high and did not realize at the time, that is what was causing my oxidation issues with my finished product. When i stopped doing that, my oxidation issues magically dissappeared.

 

[Denny's Evil Concoctions]

Usually escaping co2 scrubs o2 out of the beer.

 

[CEMaine]

I rarely get a beer to finish below about 1.018. One theory to consider is whether or not you are adequately aerating the wort before pitching yeast. I think it could be the root cause of some of my problems. Just shaking the fermenter only gives a certain percentage of oxygen, using a aeration stone is better, and pure oxygen with the stone is the best.

Someplace I read how much each method affects the oxygen content of the wort, but I can't remember where right now.

That made a huge dif for me. Was in the 1.020 range for most brews until I built an aeration rig. Now I get 1.010 to 1.013 an almost every brew.

 

[maltMonkey]

Except the oxygen that you just dissolved into the beer via the shaking is NOT ALL pushed out . Trust me, i did it on my first few batches that were finished too high and did not realize at the time, that is what was causing my oxidation issues with my finished product. When i stopped doing that, my oxidation issues magically dissappeared.

I will take your word for it--hopefully since it's an RIS it won't have as much negative impact as it would on say a pilsner. I'm sure you can understand my frustrations with these high final gravities

 

[kenb]

I will take your word for it--hopefully since it's an RIS it won't have as much negative impact as it would on say a pilsner. I'm sure you can understand my frustrations with these high final gravities

Will not be noticeable on an RIS..at first....maybe after 4-6 months you may notice it.

 

[maltMonkey]

Well, I checked the thermometer built into my MLT tonight against my digital probe thermometer, and it's dead on.....

Also, the amber ale FG is at 1.024 and done....so I'm still scratching my head a bit over this.

 

[kenb]

Well, I checked the thermometer built into my MLT tonight against my digital probe thermometer, and it's dead on.....

Also, the amber ale FG is at 1.024 and done....so I'm still scratching my head a bit over this.

Is that the one you mashed at 158? if so, it doesn't matter how much yeast/aerating you do, unfermentables are unfermentables...just mash at a much lower temp next time.

 

[maltMonkey]

Yep, mashed at 158. I've been mashing at 153°-154° ever since I discovered the issue. I'll be checking the gravities on the last 2 I mashed at this temp range in less than a week (fingers crossed).

 

[maltMonkey]

Just a quick update.....I just checked on my last 2 batches that I mashed @ 154°....One finished at 1.013 (70% att), and the other is almost done @ 1.015 (also about 70% att).

So I think I think that it definitely was mash temp keeping the FGs up. I never thought it would make such a huge difference, but you live & learn, I guess.

 

[Denny's Evil Concoctions]

Yeah, I mashed an ale at 158f once and my fg was so bloody high I think it could have been used as a meal replacement.

 

[rnrchemnerd]

I'm surprised that nobody mentioned fermentation temperatures! I just racked a nice maibock style ale to the secondary and was surprised to find an FG of 1.024 when I was expecting something around 1.014. I almost always get between 70 and 80% attenuation, so my technique is pretty good. My problem was the temperature. SWMBO always keeps the heat pretty high during winter, so after the yeast took hold, I put the primary out into a hallway by the back door. It's significantly cooler out there than it is in the apartment, so I thought it would be an easy solution. I didn't realize that the temperature drops down below 50° overnight. I'm pretty sure most of my yeast fell asleep or just really slowed down. I'm going to let this one sit in a much warmer place for a few weeks and see what happens...

 

[Denny's Evil Concoctions]

Yeah, place it warmer amd give the carboy a swirl to rouse the yeast.

 

[z987k]

If you still have this problem after mashing at 152 and reducing the crystal grains and such... go to 148. I mashed a beer at 148(on purpose) once... had only a pound ofg crystal 10, pitched us-05 and it came down to 1.002 very dry.