Consistently High FG

[Dave2340]

My experience is very limited having only taken up brewing about 6 months ago. At this point I am quite disappointed with the out come of my home brews. I seem to consistently be producing the same result - strong "home brew" taste (not sure how best to describe it), poor head, and poor final gravity. i have tried different kits but have that same after taste and unable to get my FG below 1.020. I have been clinical with my sterilizing, purchased a refractometer for accuracy, and built a STC1000 controlled fridge for fermentation control. Current brew I am chewing on was bottled at the beginning of October - PET bottled with 2 carbonation drops.
Typical brew: Coopers Pale Ale, Brew Enhancer 2, 1Kg LDM, the coopers yeast, 23L of rain water, fermentation temp 22C, and OG of 1.050. Air lock activity dies away at around 7 days at which i have taken a reading of 1.027.
I believe the FG should be between 1.015 and 1.010. I have tried different yeasts with no real improvement.
Is it possible that the rain water is the problem? oxygen?

Thanks in advance for any advise you can offer.

Cheers,

 

[RdeVjun]

Are you correcting the refractometer FG result for alcohol? Eg. http://www.brewersfriend.com/refractometer-calculator/%C2 Or, if you have a hydrometer, test FG with that instead.

I realise that FG is only part of your woes, the poor flavour is probably high-ish temperature kit twang, drop the temperature to 18C and see if pain persists but I'd also be interested to hear what treatment, if any, your rainwater has.

Hope that helps!

 

[Tex083]

You could try a little yeast nutrient, if your doing kits there can be a lack of essential elements for the yeast I believe. With the addition of rain water you may not have enough calcium & zinc for the yeast.

Hope you can get this sorted, try a saison yeast next the belle saison from danstar should chew through everything doewn to 1.005 or lower.

 

[Ciderman]

Refractometers are only good for AG brewing so you can check how the beer is tracking through various stages like mashing, sparging, boiling etc.

Once the beer is in the fermenter, use a hydrometer. I'd say most Brewers do.

 

[Dave2340]

No i don't have a hydrometer (anymore - don't bounce at all) but i have used the temperature correction at http://www.rooftopbrew.net/abv_calculator.php. i am looking at the FG level more as an indication that the fermentation is complete, not too worried about the ABV level.
I can borrow one though to compare

 

[RdeVjun]

Sadly, that's not enough- you will need to correct refractometer for alcohol %, you need the OG and the refractometer value and it will provide a corrected value.

(If I could insert a link reliably, I would, but search for "refractometer correction alcohol", there's one on Brewers Friend.)

 

[Dave2340]

Thanks Tex, how do you use the yeast nutrient? do you create a starter or do you add to the kit as you add the yeast?

 

[Dave2340]

Thanks RdeVjun, i am curious now to compare the two. i am probably making a big assumption that the gravity is the cause of my flavor problem but i have to start somewhere.

 

[RdeVjun]

Yep, at face value it would appear that the problems you outlined are related, but as with many issues in homebrewing, all may not be quite what it seems! You're asking all the right questions IMO, keep it up and I reckon eventually you should be pretty pleased with the beers, you're well on the way.
HTH! :beer:

 

[Newy]

Hi Dave,

If you are getting an uncorrected gravity reading on your refractometer of 1.027 after 7 days then I'm guessing that is a reading of around 7 Brix?

If this is correct and you started with an OG of 1.050 then the actual corrected FG is 1.014 which is right in the ball park, so its not likely to be an attenuation problem.

Flavour wise, I don't have a lot of experience with kits so will not be of much help sorry, but stick with it, its very rewarding when you start to get it right.

 

[Tex083]

Dave it's as simple as adding 3g with 10 mins in the boil. If your not boiling anything just chuck it in some hot water to dissolve it.
If you are using the refrac to check the gravity post fermentation then you need to adjust for alcohol. A refractometer works by the light entering bending based on the sugar content (like when your in the pool and it looks like your legs are broken), in the presence of alcohol the bend is less resulting in a false high number. Alcohol refracts (bends) light less than sugary wort.
Sorry for the science lesson.

 

[pablo_h]

I'm not an expert, in fact I'm fumbling through and have the bad luck of "everything that can go wrong, does". So I just have the experience of everything going wrong and finding fixes.
But the problem is poor yeast health, not enough nutrients.
Things to try:
If using dry yeast, rehydrate in cooled boiled water. Some people say that yeast don't like rehydrating in sugar/malt - it stuffs up their cell walls.
If using liquid yeast, need to build a good starter.

Oxygen: Aerate the wort a lot. Stirring, shaking whatever. In fact I like to make the kit in one fermenter, and pour it loud and proud into another. Two fermenters are handy anyway as you can use one for fermenting, carefully pour into another for bottling/secondary and have the old trub to ferment a new batch into (see below)

Nutrients: buy them in a pack, or once you got one good brew, pitch new brews onto SOME of the last trub/dead yeast

Enzymes. Yeast need amylase- a and amylase-b proteins to break down sugars. You can buy it in a packet (enzyme products are available - usually under "low carb" adjuncts but you really need to make sure it has amylase- b ). Or steep some cracked specialty grain at 65C for the enzymes (main reason why many AG brewers don't have this stalling problem often but many kit or extract brewers do, plus why partials come out better than all extract - no fresh grain/enzymes in all extract)

E: There's a lot of variables, sometimes there's no reason that stands out, just have to make 3x the effort of every other brewer to get your own brew right for no good reason. IE, I struggle to get any BE2 brew, or all malt extract brew to ferment out as well, so I have to do all the tricks in the book. I can do anything with a standard kit and dex and it just works even if I do it lazy/"wrong"

 

[pablo_h]

Also have to add you say it has a "homebrew taste", and temperature isn't an issue for you (high temp often makes a "homebrew" taste due to phenols)
Could be a cleaning issue, or maybe even water pH. Test the water, double down on cleaning and sanitizing. If any of my kit brews were 1020 SG, they'd taste sweet, not "homebrewy", unless that is bacteria are displacing yeast.

 

[Rocker1986]

If you do a mash-out and then boil an all grain batch, which is pretty much what happens on every batch (boiling at least), the enzymes are de-natured anyway. So I can't see how they'd do anything in the wort. Those enzymes break down starches into fermentable sugars during the mash, that is their job. The enzymes in specialty grains are also de-natured so these are of no use either.

I would be looking elsewhere for the issue personally. Probably the refractometer readings being false due to the alcohol content.

 

[Barge]

- strong "home brew" taste (not sure how best to describe it), poor head, and poor final gravity.

Typical brew: Coopers Pale Ale, Brew Enhancer 2, 1Kg LDM, the coopers yeast, 23L of rain water, fermentation temp 22C,

Cheers,

Rain water aside, I would say this is your problem. The yeast that comes with the coopers aussie pale ale is actually 2 yeasts, a lager yeast and an ale yeast. I think coopers do this so that the yeast will ferment across a wide temp range. They also don't provide enough for a 23L batch @ 1.050, which means you are underpitching. The result is, in your case, that the lager yeast is fermenting much to warm and producing off flavours.

Another thing to consider is the difference between ambient temp in the fridge and the temp in the FV. If the fridge is set to 22C, then the beer is probably at least 24C. Fermentation is an exothermic process, which means that heat is produced.

I typically set my thermostat to 16C so the FV sits at about 18C. You need to ditch the coopers yeast for something better. Try Us-05 or Nottingham. Both produce clean ales at 18C and come in 11g packets so you should get away with pitching one, as long as it is as fresh as possible.

I agree with others that you are better off with a hydrometer. Much more reliable than a refractometer for ferment(ing)/ed wort. Even for unfermented wort, most refractometer readings need a correction value that is unique to the device and must be determined by the user. (Google it - basically need to compare refrac reading of unfermented wort to hydro reading). I occasionally brew AG and typically only use it to determine the S.G. into the boil.

As far as nutrient goes, if you are boiling up some extra hops, grain, etc, just throw the coopers yeast into the boil. This will obviously kill the yeast, but dry yeasts are packaged with lipids that the yeast needs to build cell walls, which can't hurt.

 

[Dave2340]

Thanks everyone for the replies. I am thinking now that i have two unrelated issues.

The first is the High FG readings. Newy is spot on here. I found a calculator on Brewers Friend that matches his figures and explanation. If my brews were under-fermented, as my unaltered readings would suggest, i would be experiencing secondary problems with my bottles - that I'm not. From now on i will be using the calculated figures as my guide and recorded in my logs.

Second issue is my rain water that you all have suggested plus one additional variable that Anthony from my local home brew shop enlightened me to - wild yeast in my rain water tank. I have tried a number of different styles and have experienced the same after taste flavor, seems to agree with the suggestion that the same wild yeast is present in each of my brews. After all the water came from the same source.

Next brew i am going to boil all the water used prior and to use a yeast nutrient to compensate for the lack of essentials in my water source. I will post the results for future reference.

Thank you all again for taking the time to look into this for me.

Cheers
Dave

 

[djsmi4]

wild yeast in my rain water tank

Spewing :-(

Dave - I'm no expert but I'll add my experience with my recent APA brew here - I had the fridge temp set to 18*C and it stalled after just a couple of days. A gentle shake of the fermenter & bumping the temp up to 20*C and it was right for the rest of the fermentation period. I put this down to 2 things:

1. Barge's comment on exothermic activity (18*C got it through the first part)
2. My particular (Coopers APA) yeast sachet probably didn't have much lager yeast in it by chance?

I hope you find simply boiling your tankwater & adding yeast nutrient will do the trick for you. Let us know how it goes, I'll keep it in mind if I ever have any water quality issues.

Cheers

Dave

 

[RdeVjun]

Yep, IMO your LHBS' Anthony is quite right and this is why I asked about your rainwater treatment back at the start.
Campden tablet might be another way to treat it if firstly boiling and then cooling it all is a PITA. FWIW the Poms seem to dose their water in that way quite a bit but not so much here.
I doubt if yeast nutrient would be that helpful, kits should have all of the nutrition it needs already, but I guess it won't hurt.
I'd also add that it isn't too late to test bottled beer for the FG with your hydrometer, if there's any left then you just need to decarbonate it and allow it to come up to room/ hydrometer temperature. You could also confirm the refractometer correlation if you are so inclined.
Also your LHBS and local homebrew clubs should be able to advise on specific issues from a sample, if not then ditch them and try to find another!

 

[yumpet]

Mate, i'm on tank water aswell, i've started filtering the water before i throw it in the FV, it has made quite a difference, i found that most of my beers had a similar taste regardless of the style i was making, after filtering it properly its stopped doing that.

 

[warra48]

Just to put another spin on why the OP has an apparent high FG is to look at the recipe makeup, with all of this in a 23 litre brew, and only a single pack of dry yeast:

1. Coopers Pale Ale
2. Brew Enhancer 2
3. 1kg Light Dry Malt Extract

It'll bet it will never go lower than the 1.017 calculated by some others on here. The culprit is probably the amount of LDME.

I'd suggest putting the ingredients through a reliable brewing software program to obtain a predicted OG, then calculate say 75% apparent attenuation to give a suggested FG. I'd be very surprised if it will be less than 1.017.
(I'm not doing it, because my settings on BS2 are for AG, but someone else may volunteer).

Look at rejigging the recipe if I'm correct.