Very high FG - Help!

[philly.dunne]

Hey guys,

I did my first all grain brew about 10 days ago. I had bought the Big Book of Brewing by David Line, so I modified his suggested first brew to make it a bit hoppier  The recipe was this:

3.5kg pale ale malt mashed for 90 minutes. I may have mashed the grain a little hot, as I was unused to the process

60 minute boil with 30g Chinook hops (0 minutes) and 100g Cascade hops (10 minutes). I also added approx 500g of demarara sugar to the boil

I pitched in two sachets of lallamand Bry 97 yeast and left it in my shed overnight as I was under the mistaken impression that cooler temperatures would be better. When there wasn't much fermentation after 24 hours, I brought it indoors and fermentation started. It didn't form much of a krausen, but seemed to be merrily bubbling away. I didn't have a hydrometer to measure og, but when I measured the specific gravity today (10 days later), it's 1.040, which seems very high. The krausen has died away and fermentation seems to have mostly stopped. Since I have no og reading, I can't figure out how much alcohol is in the wort. It tastes delicious, very malty and with a nice smooth hop character, but I'm worried there is very little booze in it!

Is this fg reading very high?

Is there anything I could do to bring the fg down/increase the amount of alcohol in the brew?

Should I pitch more yeast or add more sugar?

Any help would be very gratefully received.

Cheers,

Phil

[philly.dunne]

Yes, measured it with a brand new hydrometer. I didn't check the hydrometer against water though, maybe I should do that to make sure it's working properly....

[Kieran the Human]

What was your OG? What temp did you mash at?

[JD]

You say you mashed at a high temp. This is probably at the root of what's happened. Mashing normally occurs between 63^oC and 69^oC. The higher mash temp means more complex sugars are extracted but these are not that fermentable. You say it tastes delicious and is quite malty. This suggest that there was extraction, but not necessarily the kind that produces fermentable sugars. You added demarera sugar, which is 100% fermentable, but only half a kilo.

A second alternative is that your yeast packets were duds. It can happen. The fact that you used two, probably makes this unlikely.

Finally, a third alternative is that you have a dodgy hydrometer.

My money is on the mash temps.

I suspect the stuff you made will not ferment down much more as it stands. All is not lost though. You'll just need to brew a second batch, this time mashing at 63^oC. You'll get no body worth talking about at temps this low, but you will get plenty of fermentable sugars. Once this brew has fermented, you can blend it with the first batch. Make sure the first batch is healthy before you blend. It probably doesn't have enough alchohol to be antiseptic, but it probably does have enough hops to keep the bugs at bay.

Next brew, keep a good eye on your temperatures and do measure your OG. It is one of the most important measurements you make when brewing. Do take the wort temperature at the same time so you can correct your hydrometer reading. Write your measurements down on something before you adjust them.

/JD

[DEMPSEY]

When you say you mashed high temp,how high  : . If you mash at a higher temp then you may have killed off the B amylase that don't work at the high temp. The A amylase work at the higher temp making big Dextrines that are considered the non fermentables. The B amylase take these Dextrines  and chop them up into Maltose which are your fermentables.
Alpha Amylase is happy at between 67c to 72c
Beta Amylase is happy at between 55c to 66c
mashing at around 66c to 67c is what most people do. If you are mashing too low the Alpha's work very slowly but if you mash too high the Beta's die a horrible death and so no lovely Maltose babies foe the nice yeasti's to eat

[philly.dunne]

Thanks for the help lads, very much appreciated 

Ok, so the good news is that I checked my hydrometer against water and it read 1. Then I checked another sample of the wort in a different measuring jar (the first time I had checked it in the tube that the hydrometer came in, which the manufacturers said would work as a measuring tube) and got 1.020, which sounds a lot better. There might be some alcohol in it after all!!

I don't have a figure for OG unfortunately. I am a total newb to this (this is my first ever brew) and didn't have a hydrometer when I did my brew day. Must have forgotten to order one when I bought the rest of my kit.

I probably mashed at slightly over 70 degrees. Definitely less than 80, so perhaps things are not lost? I was mashing in a boiler and trying to keep the element down as low as possible/turn it off and on to keep the temperature constant. Just inexperience I guess.

Thanks for the tip about blending it with another batch JD, I might just do that. 1.020 seems to be just outside the usual range for FG for ales, do you think it might be worth just bottling it as is anyway? if it hits between 3 and 4% ABV, I'd probably be happy to chalk it up to experience and just drink it....

Today has been a lesson in both taking gravity readings, keeping notes and being fastidious about mashing temperatures, thanks again

[nigel_c]

I'd say leave it a few more days. A few days in the shed would have caused the yeast to slow do completely. If you mashed in the low 70's it will finish high but I'd bet it will drop a few more points before it finished up. I'd up the temp slightly and even stir up the yeast at the bottom with a sterilised spoon and that should tick start the fermentation. 

[donnchadhc]

1.020 isn't too high, as said above try stirring up the yeast with a sterilized spoon. You only need to get it down a few more points.

Failing that, pitch a new pack of yeast, something neutral like Nottingham ( which will also tolerate cooler temps) Try pitching in an extra 100 g of sugar (boil it in 300 odd ml of water and allow cool before pitching). This will help restart the fermentation and help dry the beer .

[JD]

One other thing about taking gravity readings (your two widely varying readings suggest it might be relevant): you need to ensure no bubbles are stuck to the hydrometer. These will increase the buoyancy of the device and give a false high reading.

Most people will spin the hydrometer after they immerse it to throw off the bubbles before they take a reading.

[DEMPSEY]

If it is too high he could dissolve some sugar in water and add it to the fermenter. It will increase the amount of liquid and the sugar will be fermentable so the final sg will be lower.