Wheat Beer Refuses to Ferment

Australia & New Zealand Homebrewing Forum

Help Support Australia & New Zealand Homebrewing Forum:

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

citizensnips

Well-Known Member
Joined
9/7/07
Messages
769
Reaction score
127
Hi all, on Tuesday I brewed a wheat beer, pitched the yeast the following day (US-05) and saw very little activity the following 48 hours. Original gravity was spot on at 1.050 and it said it had fermented down to 1.046. As the yeast was sent during the massive heat wave last week from Queensland I figured it was most likely dead and purchased another packet, pitched that yesterday and still no activity today. There is almost a little crema on top but that is it. All the while the airlock has shown no signs of fermentation.....even though I know not to rely on it, I have tested it and it is air tight and does work just by simply applying a little pressure to the sides. Anyway here is the grain bill below, it is meant to be my take on an Australian Wheat beer with some different ingredients. Only a little test batch in case it was terrible, the annoying thing is it tastes fantastic as wort. Im guessing it's something to do with the mash and conversion of the unmalted flaked wheat perhaps? It was from Bluelake if it makes any difference. From my all my reading I was led to believe it was fine to do this mash schedule....and the rolled oats were Uncle Toby's that are pre steamed and gelatanised or what ever it is so figured they would be right for the job.
If anyone has any pointers or thoughts it would be much apreciated.
Cheers
Snips
Code:
Recipe Specifications
--------------------------
Boil Size: 23.94 l
Post Boil Volume: 19.24 l
Batch Size (fermenter): 17.00 l   
Bottling Volume: 16.20 l
Estimated OG: 1.050 SG
Estimated Color: 6.6 EBC
Estimated IBU: 21.0 IBUs
Brewhouse Efficiency: 68.00 %
Est Mash Efficiency: 74.0 %
Boil Time: 60 Minutes

Ingredients:
------------
Amt                   Name                                     Type          #        %/IBU         
1.65 kg               Pilsner (2 Row) Ger (3.9 EBC)            Grain         1        40.2 %        
1.65 kg               Wheat, Flaked (3.5 EBC)                   Grain         2        40.2 %        
0.60 kg               Oats, Flaked (2.0 EBC)                   Grain         3        14.6 %        
0.20 kg               Cara-Pils/Dextrine (3.9 EBC)             Grain         4        4.9 %         
8.50 g                Galaxy [14.30 %] - Boil 60.0 min         Hop           5        18.4 IBUs     
6.00 g                Galaxy [14.30 %] - Boil 5.0 min          Hop           6        2.6 IBUs      
5.50 g                Coriander Seed (Boil 5.0 mins)           Spice         7        -             
125.00 g              Marmalade Jam (Orange) (Boil 0.0 mins)   Other         8        -             
9.00 g                Grapefruit Peel (Boil 0.0 mins)          Spice         9        -             
1.0 pkg               Safale American  (DCL/Fermentis #US-05)  Yeast         10       -             


Mash Schedule: BIAB, Medium Body
Total Grain Weight: 4.10 kg
----------------------------
Name              Description                             Step Temperat Step Time     
Saccharification  Add 26.45 l of water and heat to 66.0 C 66.0 C        90 min        
Mash Step         Add -0.00 l of water at 72.0 C          72.0 C        10 min        
Mash Out          Add -0.00 l of water and heat to 75.0 C 75.0 C        0 min
 
I believe (from a Weyermann lecture a few years ago) that German pilsener malts have enough diastatic power to handle 30% of their weight of non malted adjuncts. I"ve forgotten whether that referred to a kilo of pils plus 300g of adjunct or a mixture of 70% pils and 30% adjunct. Which are slightly different ratios. However in your case your non malted adjuncts are more than your diastatic pils malt. So I would guess that there's a lot of unconverted wheat and oat starch left in the mixture that could be giving a high gravity reading, and perhaps the first lot of yeast went as far as it could go with the available sugars in the wort.

I'm not familiar with wheat beers, but that's just my 2 cents based on the chemistry.
 
+1 for Bribie's comments. Not enough Pils malt for diastatic conversion with the flaked wheat and oats content.
 
Faaaark so in other words this has to go down the lawn/garden/drain?? :( If the recipe was to be done again would I be better off just to sub the flaked for malted wheat i.e. the barret burston on CB that says it can be used for up to 80% of the grain bill?
 
Yes I'd use malted as opposed to flaked wheat. Also with a lot of adjuncts I'd use Aussie malt, especially Barrett Burston Galaxy that's a diastatic monster. In fact I'd bet that if you had used BB in your recipe as opposed to the German you might actually have got away with it. I've always used Aussie Malts when doing cereal mashes and they are very powerful.

I've been told that BB even have a malt that's for the Asian market (who value high diastatic malts for converting rice for domestic beers) that can zap huge amounts of adjunct. Not available for home brew market apparently.
 
Cheers for the help Bribie, I did actually use BB Pilsner Pale Malt and Blue Lake for the flaked wheat. Guess maybe next time I'll go nearly all malted wheat and maybe 10% faked or so. Damn shame I lost her all, guess its a learning curve none the less.
 
I can't believe something with 40% pilsner mashed for 90mins in the middle of sweet spot for the enzymes would only drop four points. Back of a fag packet would give an apparent attenuation of the base malt of 4/20 ( 20%). I would be checking mash temps for your next brew with a couple of thermometers.
 
Wey Pils has a diastatic power of 110 lintner, both flaked wheat and oats have zero.

Wey Pils: 1.65kg x 110 = 181.5
Flaked Wheat: 1.65kg x 0 = 0
Flaked Oats: 0.60kg x 0 = 0

So Total DP 181.5 / Total grain 3.9 = 46.5 Lintner
You need >= 30 Lintner. So 46.5 is plenty.
And as you said you hit the OG, so this is not an issue. It it was a too much adjunct for conversion you don't get the gravity points as you have not converted all the starches to sugar.


Even mash temperatures, I don't think you could actually hit the OG and get such an unfermentable wort with just 5% attenuation.

Give the fresh yeast some time to wake up, it may just be old stock. What temperature is the wort currently at? By eye, is there any signs of fermenting?
 
Not that I've got much experience with adjunct brewing, but I certainly wouldn't tip it out just yet.
Give it a few more days and take a reading then. If you're lucky you're just having some 'yeast issues'.

As malt shovel says, you have 40% pils in there, you should be seeing some drop in gravity.
 
[SIZE=medium]Definitely too much adjunct in the mix, under ideal conditions and with a very well managed mash regime 40% W/W adjunct is close to the upper limit, without resorting to using additional enzyme preparations.[/SIZE]
[SIZE=medium]malt_shovel and a couple of others also raises a very good point, the 1.6Kg of Pilsner and whatever amount of the adjunct it converted should give you more fermentables than are apparent – so a good long look at your processes could be well worth while, as could be a bit of patience.[/SIZE]

[SIZE=medium]Galaxy isn’t the answer and I wish we could put to bed this often repeated bit of AHB conventional wisdom, OK it’s a pet hate I know that but it always gets me riled.[/SIZE]
[SIZE=medium]Galaxy can be very helpful when making high adjunct beers because it is extremely high in B-Glucanase, which is only a benefit if you are doing a Glucan rest (mid 30’s), but if you mashed in at normal temperatures you will have denature it. What I mentioned before about a well managed mash regime in this case means a good step mash starting around 30o[/SIZE]C.
[SIZE=medium]Apart from its high (and it’s the highest available) B-Glucanase content Galaxy isn’t anything special when it comes to Diastatic Power (Starch Reducing), that is measured in o[/SIZE]WK (Windisch Kolbach) or [SIZE=small]o[/SIZE]L (degrees Lintner in American literature). If you have a look at information provided on the Barrette Burstone website you can see that its [SIZE=small]o[/SIZE]WK is about the same as their Pilsner Malt (250-330 [SIZE=small]o[/SIZE]WK for the Pilsner and 270-325 [SIZE=small]o[/SIZE]WK for Galaxy).
[SIZE=medium]Most of the information on the web about Diastatic Power will be American and all the malts we get in Australia will have specifications in o[/SIZE]WK, if you want to convert between [SIZE=small]o[/SIZE]L and [SIZE=small]o[/SIZE]WK, the equation can be found on Wikipedia.
[SIZE=medium]A bit of reading on what Diastatic Power means could be helpful if you are designing high adjunct beer.[/SIZE]
[SIZE=medium]As QLDKev points out, you have hit your target OG, however there is a lot of difference between Extract (anything pulled into the wort from the grain) and a wort that will ferment to make good beer. Using a lot of adjunct can give worts with very high Glucan (and other protein) and starch contents, that all contribute to the OG. But they don’t really explain the very small drop in gravity.[/SIZE]
[SIZE=medium]It almost looks like you have created a “Perfect Storm” where everything that can go wrong has, might be best to put this one down to experience, but if you want to make high adjunct beer you really do need to be step mashing, if you don’t want to spend money on a more complicated brew rig it might be worth looking at decocting. You would need a decent sized pot and a kitchen stove, just take your decocts (soup ladle works well) and heat them slowly to a boil before stirring them back into the main mash.[/SIZE]
[SIZE=medium]I would mash in with a lower than normal for BIAB water to grain ratio (say 3:1), in the low 30’s (Glucanase) then step to mid 50’s (Protease) then to saccrification (personally I would spend some time in the low 60’s to give the Beta a chance) and maybe be just do a hot water addition to 65-67) and to mash out. Mashing in a bit stiffer will leave you plenty of water to do the last couple of steps. But for god’s sake plan those decoctions and hot water additions in advance.[/SIZE]
Mark
 
Here is a little table to show the optimum temps
table2.gif
Sorry about the small size but I borrowed it from BYO magazine.
Click to expand !
Nev
 
Thank you all for the replies, MHB appreciate the long response. I have just checked the gravity and it has dropped to 1.026 :super: . Obviously the co2 is escaping somewhere other than the airlock even though it appears airtight. There was the tiniest mark from krausen which got about 5mm above the wort. It never really looked to active, just kind of a little yeast slurry on top. I've got it set on 18.5 where its been the whole time. Anyway hopefully by some miracle it keeps dropping points, although I'm not holding my breath. As you have all said its most likely the pilsner fermenting out. Anyway I shall keep you all updated.
Cheers
 
Oright so an update. As of yesterday or maybe even the day before she is at 1.020. I turned the stc to about 20 degrees and gave her a gentle stir with the brewing spoon to rouse the yeast up to see if there was a possibility of dropping a couple more points. The interesting thing is though that the beer doesn't actually taste that sweet, hence I'm guessing all the sugar has fermented out and what's left over is starch?? I'm wanting to know if there is any problem bottling a beer like this with left overs still in it? Hoping to get some advice from anyone who knows and what the potential pitfalls of this situation are? Because at the moment the beer doesn't taste to bad at all and if anything has a nice body to it :p
 
Complete and utter decimation of the entire North Eastern colony of sugar gliders. Don't do it!

* N-B: I have no idea.
 
My regular wheat beer I brew has 50/50 (3kg/3kg) BB Pale malt and Bel. Wheat malt. I use 2x packs of WB-06 in a 20litre batch and the airlock never bubbles . Starting with a high OG it gets down to about 1.024ish in about 5 days on a cycle of 18 - 20 deg. C. Freaked me out the first time until I checked with refractometer daily. Sometimes it takes a good 24 hrs to kick in. Is it possible that wheat absorbs more CO2 somehow? Not sure but it always ferments regardless.
 
Back
Top