AG finishing gravity 1.020

Shop deals on ebay
shop deals on amazon
Advertise with us
The Homebrew Forum

Help Support The Homebrew Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
brucestevenson916

brucestevenson916

Beer Apprentice
Joined
Jun 21, 2012
Messages
59
Reaction score
3
4 out of the last 5 AG brews I have done finish at 1.018-20.
Different styles and ingredients, different mash times and temps, tried 64deg 2 hour mash, 67deg 2 hr mash, 3 x 66deg 90min mashes.

The one beer came out at 1.010, the only difference with this beer is it had 100g black malt.
All have had 100-500g of wheat, but that has never mattered before.

I have a temp controlled stc2000 fridge. Normally set to 20deg.

Also tried 3 different hydrometers

Any ideas why? Also I've never tested my water or ph or used salts (don't know how)
 
Different, mostly I date mangrove jack yeasts, Bavarian wheat, bohemian lager, west coast us, and Belgium ale.
 
Dunno then! Seems odd. I've not used any MJ yeasts. Under pitching can cause this I believe, do you rehydrate the yeast? Are they normal batch sizes? I can't think of anything other than a it being yeast related.Old yeast?
 
20-23ltr and rehydrated over night then add dme to get it started on the day.

The only difference is I've moved house and am wondering if it's the water causing the problems. Up in a village in Aberdeenshire.
 
You can send a sample of your water to Murphy and Sons and they'll send you a full test report plus advice on how to treat your water for different beer style for around £22. I had problems with Mangrove Jack Newcastle finishing at 1:023 or thereabouts but it is known to be a low attenuator and I saw reports on their other strains generally performing OK. If you don't want to spend money on water testing, you could try a well known reliable attenuating yeast like Nottingham ..in from Gervin G12 or Wilko Gervin to see if that makes a difference. The batch with black malt reaching 1.010 might indicate a ph issue (ie water too alkaline) but I'm not an expert..and not sure 100gram would have such a significant effect.
First you could check your local water company specs (usually published on their website). They may not give reserve alkalinity but should give total hardness which should give you a starting point ..you could compare with your old water supply company.
 
check this link out from Scottish water. Unless you are in the Orkney's or Shetland there are only a few hard water areas...most are soft. Scottish water even split out Calcium and Magnesium which is handy...no real need to pay for an analysis if you can identify your area...though bearing in mind its 2013 data and not sure of variability.
http://www.scottishwater.co.uk/~/me.../Water Quality/ScottishWaterHardnessData.ashx
Calcium in most supply areas is quite low (in line with my memories of ultra soft water living in Scotland) so you might want to add some in from of Brupaks dry liquor salts...info on dosage info on brupaks water treatment bit of their website. Probably no need to correct alkalinity with acid solution (brupaks CRS) . I am not familiar with the names if the Aberdeenshire supply areas.
 
so my area on that is white hillocks. meaning I've got softy water and the following:-

10.51mgCA/l calcium
0.63mgmg/l
28.80 Hardness as mg/l CaCo3


what does this mean for brewing in English? what is your minimum readings for the average style?
 
I had a problem with the work horse yeast being too floccuant and it dropped out of suspension too quickly causing my beer to be full of diacytl.

If yeast is too floccuant it doesnt ferment the wort fully leading to stuck brews - maybe this was your problem?
 
brucestevenson916 said:
so my area on that is white hillocks. meaning I've got softy water and the following:-

10.51mgCA/l calcium
0.63mgmg/l
28.80 Hardness as mg/l CaCo3


what does this mean for brewing in English? what is your minimum readings for the average style?
Click to expand...
Try the water calculator at the top of the site, in 'calculators'. You'll probably find it tells you to add some gypsum amongst other things...
 
MyQul said:
I had a problem with the work horse yeast being too floccuant and it dropped out of suspension too quickly causing my beer to be full of diacytl.

If yeast is too floccuant it doesnt ferment the wort fully leading to stuck brews - maybe this was your problem?
Click to expand...

I bought some of the work horse yeast to use when it gets a bit warmer as it says it can cope up to 32c. Is it not worth using then?
 
Hops_and_Dreams said:
I bought some of the work horse yeast to use when it gets a bit warmer as it says it can cope up to 32c. Is it not worth using then?
Click to expand...

Not sure tbh. I also bought it to use during the summer so I thought I'd test it out during the winter.

It was quite an odd yeast. It seemed to floc out too quick which I'm fairly sure caused it to then not reabsorb diacetyl - I don't think I brewed too warm or anything the ferment temp stayed around 20c maybe 21c max (plus it's supposed to be able to cope with temps up to 32C).
I then roused the yeast back into suspention. After it had settled out again a few days later it formed a second kraused and started to ferment again, which I've never had before.
The tast of the beer (a mild) was definatle not the best I've ever made. Although drinkable, it has a slight twang almost like a kit.

I don't think I'd use it again. I'm going to have a go at the mauribrew english ale yeast during the summer as that also has a max temp of 32C. That or going back to using a water bath and ice (which can be a bit of a faff)
 
Could you not rouse the work horse yeast to encourage it back into action?
 
You might want to give it a go on a small brew and then harvest the yeast if it turns out ok. I might of done something that caused it to be not very good - can't think what though. There also doesn't seem to be that much info out there on the forums either
 
I had some really odd readings and realised it was not the beer but the method of reading with the hydrometer. It would seem there are 20ºC and 60ºF hydrometers so first one has to find which type you have I hope 20ºC as getting sample to 15.5ºC is not that easy. Second any gas in the sample will also cause error so needs leaving to allow any gas to leave the sample. At first I thought I could use correction charts but it turned out glass is not one substance but a collection and the coefficient of liner expansion varies a lot so unless the conversion scale came with the hydrometer it's useless as we have no idea of the glass used.
I have two 60ºF hydrometers one glass one plastic at 60ºF they match but at 20ºC they don't. Since I normally brew at 20ºC this is clearly a problem. Plastic one is now no longer used.
 
Bruce916,
Base don you water profile, you don't need to do any acid treatment, but should a something in the order of 6 grams each of calcium sulphate (gypsum) and calcium chloride to get the calcium levles up to the desired levels (100ppm) and to optimse mash ph. Since your magnesium is low I'd also add 4 grams Epsom Salts (magnesium sulphate) if it were me. Alternatively, to simplify things you could add 12 grams Brupaks DLS (dry liquor salts) instead...it'll do the same thing and get to around 100ppm Calcium. For pale ales and bitters you my want to add a little more,...check out their water treatment page on their website. All above assumes 23ltr brew size....add the salts to the mash.
http://www.brupaks.com/water treatment.htm
 

Similar threads

Berry454
Adding hops at the start of fermentation and hot fermentation temperatures?
Replies
4
Views
603
MashBag
MashBag
gingerneil
Dry Hopping AG Italian Pilsner
Replies
4
Views
649
Leon103
Leon103
David Woods
Undercarbed All Grain - can it be fixed?
Replies
10
Views
668
Twostage
Twostage
M
Floating oily balls post fermentation - Help please
Replies
3
Views
516
Rwilts
Rwilts
Nottsbeer
Stuck fermentation?
Replies
13
Views
867
peebee
peebee

Latest posts

Back
Top