Glucose Repression ?

[cleaninglady]

Greetings to All , good to be here !

I have a bit of a question about a beer i started the other day.

I have done four brews since starting a month ago and this is my fifth so please excuse any shortcomings in descriptions etc.

I have been studying as hard as time permits ; reading Charlie Papazian's : The Complete Joy of Homebrewing and Brewing Crafts by Mike Rodgers-Wilson but the info is still soaking in...

I made what i suppose could be called a Dark IPA or Dark Ale using :

Muntons Blonde All Malt Can 1.5Kg

Brewcraft Irish Stout Converter Kit. 1Kg (Breakdown probably : Dark MDE 500g , 250g Corn Sugar , 250g Dextrose also containing Some Chocolate Malt grain approx 50g and 15g Goldings Hop Pellets).

250g Crystal Malt Grain ,

1Kg Glucose/Dextrose (This is maybe my problem...)

25g Amarillo Hop Pellets (used as bittering and finishing hops)

After pitching the yeast (Munton's Gold 6g at around 22C) ; it took around 20 hrs to get active and krausen was very thin (about one inch maximum) and had already subsided by this morning.(I pitched at Midday yesterday and view it at 10am this morning).

No Airlock action yet.

I usually get action from Muntons Gold within a couple of hours (even in Hot weather) and the Fermenter will bubble away happily for about a 4 days before slowing down a little.

I am concerned that the addition of the 1Kg of Glucose has caused Glucose Repression ? ( I use this term Extremely Loosely...)

I came across the researching yesterday , can anyone shed light on whether this is what is happening.

The yeast does not look like it has fully rehydrated , there are patches of brownish yeast on top of the Krausen that look either dead or inactive.

I have attached my recipe and method from my Homebrewing records , apologies if it looks like a bit of a Frankenbier !!

cL

View attachment Brew___0005.rtf

 

[Pennywise]

Nothing sounds strange to me, krause size and how long it hangs around will all depend on temp and how healthy the yeast is, I would check your gravity over the next couple of days to make sure it's still dropping. IMO one 6g pack of yeast in that quite strong brew is not enough, I'd prolly have use 3

Edit: Welcome to the forums

 

[manticle]

A good amount of information there. What you haven't provided is the original gravity and the subsequent gravity. Not all fermentations are visually vigorous but the brew may still be fermenting.

At a rough guess though, the brew might be struggling because there's a fait bit of extra stuff in there (not just the dex) and you've only provided it with 6g of yeast. Is this a usual kind of brew for you or a bit heavier?

Supposedly, yeast can sometimes feed on simpler sugars first (like dex) and then get a bit lazy and refuse to digest the maltose. That's why you may read suggestions to add at least some of the glucose or dextrose in after high krausen - done with some Belgian styles for example. A lot of brews use sucrose or glucose pre-ferment though so that's not absolute. I would suggest it's a good idea with high gravity brews though.

If the gravity is still dropping it's fermenting. If the gravity is stable and where it should be, it's finished although I doubt that it would be yet.

 

[cleaninglady]

Wow !! Thanks Homebrewer79 and manticle for that quick reply !

I was thinking maybe it might need more yeast , i bought the Muntons Gold i used from the local brew shop and didn't use the yeast from the Muntons Blonde can.

Do you think i can use the can yeast or should i get more Munton's Gold ?

cL

 

[Dazza_devil]

I've done 3 Muntons kits in the past and found the yeast in the cans to be quite acceptable but this would depend upon how old the kit is.
I'm not sure but the Blonde yeast with the can could possibly be a Lager yeast which would ferment at lower temps than the Gold.

 

[manticle]

Fair bit of malt in addition to the dex in this one though Boagsy.

@cleaning lady - check the gravity first before worrying about new yeast. If it's stalled there are better ways of rousing than just sprinkling in new yeast. Sometimes sprinkling dried yeast on a stalled brew does nothing.

 

[cleaninglady]

A good amount of information there. What you haven't provided is the original gravity and the subsequent gravity. Not all fermentations are visually vigorous but the brew may still be fermenting.

At a rough guess though, the brew might be struggling because there's a fait bit of extra stuff in there (not just the dex) and you've only provided it with 6g of yeast. Is this a usual kind of brew for you or a bit heavier?

Supposedly, yeast can sometimes feed on simpler sugars first (like dex) and then get a bit lazy and refuse to digest the maltose. That's why you may read suggestions to add at least some of the glucose or dextrose in after high krausen - done with some Belgian styles for example. A lot of brews use sucrose or glucose pre-ferment though so that's not absolute. I would suggest it's a good idea with high gravity brews though.

If the gravity is still dropping it's fermenting. If the gravity is stable and where it should be, it's finished although I doubt that it would be yet.

Thanks for this info , really helpful.

I suppose this is reasonably similar heaviness wise to the other brews i've done so far (this being only the 5th) ; i've gone big and ambitious from the start , no real failures or infections yet.

I've done two IPAs , a Kaiser Weissen and an Imperial Stout ; all partial recipes.

I have so far used DME rather than glucose but it's just what i had at hand the other day and i couldn't be bothered riding my bike the the Richmond Brewcraft store from Northcote to get more DME (saving money too...)

I was a little worried that the dextrose might compromise the flavour as i've tried to stay all malt up until now.

 

[cleaninglady]

yep , i'll give it a day or two then rouse and check the gravity.

I probably shouldn't worry about no airlock action , my Wheat beer didn't bubble and still turned out ok.

@boagsy , you are right , i completely forgot that was a Lager yeast in the can.

thanks again to all

cL

 

[Pennywise]

yep , i'll give it a day or two then rouse and check the gravity.

Check you gravity now, then in a day or 2 check it again to see if it has fallen, if it hasn't then you have a stuck ferment on your hands.

 

[cleaninglady]

Check you gravity now, then in a day or 2 check it again to see if it has fallen, if it hasn't then you have a stuck ferment on your hands.

Cheers , will do...just checked : 1.053 down from O.G. of 1.063 (24 hours ago when pitched) , huge amount of head when pouring into the test tube.

Wort is tasting far too sweet up front ; Goldings are there , Amarillo not so prominent.

I'm really regretting this glucose now...hopefully i can adjust the sweetness somehow.

I was thinking Dry Hopping with Cascade in about a week.

Any ideas ?

 

[Dazza_devil]

I have thrown a bit extra (1.056, 1.060) in with my Muntons kits and they took off OK eventually with just a sprinkle from the kit yeast but found that they had a tendency to finish high with regards to FG. Never used quite that much dex. though (250g,500g) but I doubt it would be a problem, some people have used just the kit and a kilo of dex without any problems. The dextrose could help your brew to finish at a lower FG giving a drier result, a bit thinner with less body but should still be OK from what I can see.
I'd recommend relying upon your hydrometer for fermentation progress and look into rehydrating/making starters/using more yeast for higher gravity beers in future.
Check out this http://www.mrmalty.com/calc/calc.html site which can be handy for recommended pitching rates.

 

[Faithy]

You could try stirring it with a big sanitized spoon to get more yeast in suspension again.

I think your fermenter lid may not be sealing properly if you had an inch thick krausen and no air lock activity. Try undoing the lid and turning it anticlockwise until it sits flat, then screw it up again. You might want to use some kind of lube on the O ring and air lock grommet in future.

Dry hopping a darker beer with Cascade hops seems strange to me too.

Good luck.

 

[Pennywise]

Well it's fermenting so I'd just let it go, check the gravity every few days to make sure it's still firing, hopefully it doesn't stall, when you reach your target (or close to) gravity leave it for another week, check gravity again to make sure it hasn't fallen any more, bang, ready to bottle/keg.

 

[cleaninglady]

Does anyone have any ideas for balancing out excessive sweetness or do you think it might right itself by the end of Fermentation ?

cL

 

[Dazza_devil]

I doubt it will end sweet with all that dextrose in there.
See how it goes mate, it's only just started to ferment.
Hopefully it will finish nicely and mature in the bottle even better.

 

[cleaninglady]

Yep , patience !

cheers

cL

 

[QldKev]

Supprised no one has asked you what temp is it at now? You pitched at 22; but did it drop dramatically overnight?

QldKev

 

[Screwtop]

Munton's Gold 6g at around 22C

Any fermentation problems, stalled ferment or finishes high - refer here: http://www.mrmalty.com/calc/calc.html

Screwy

 

[manticle]

Cheers , will do...just checked : 1.053 down from O.G. of 1.063 (24 hours ago when pitched) , huge amount of head when pouring into the test tube.

Wort is tasting far too sweet up front ; Goldings are there , Amarillo not so prominent.

I'm really regretting this glucose now...hopefully i can adjust the sweetness somehow.

I was thinking Dry Hopping with Cascade in about a week.

Any ideas ?

The malt is what is giving the sweetness - the glucose will ferment right out and actually potentially balance up the malty sweetness. How it tastes now though is not how it will taste when it's ready. You put sugars in a big container of water and yeats, it will taste sweet until the yeast have fermented the sugars.

Particularly in extract brews like this which are heavy on malt, some dex can be a great thing to help balance things as extract brews can often underattenuate. It's up to you exactly how much to use - I'd shy away from using the full kilo but a dex addition in an all extract brew can be a very good thing. No need to regret it though.

Check screwy's link and take into account Kev's question (if temp drops too low the brew may stall although too high will make estery beer).

In future, if you need malt extract, you can order from grain and grape. They deliver via Australia Post which will be $7.45 up to 20 kg. Obviously if you put a few things together in a box at once you can make the postage worth it. You can get grain, hops, yeast - basically everything you need for any level of brewing. Easier than driving to Richmond. Thye also do larger bags if you want to buy a bit more bulk.

There are other suppliers worth a look - see if the craftbrewer prices compare to GG and then add the postage from QLD - a lot of people here use both suppliers. I suggest GG because that's where I go and they are Melbourne based but shop around. Brewcraft is probably not your best bet. Links to both stores top right of the page.

 

[QldKev]

(Munton's Gold 6g at around 22C)

Any fermentation problems, stalled ferment or finishes high - refer here: http://www.mrmalty.com/calc/calc.html

Screwy

But putting that in context of the full sentence

After pitching the yeast (Munton's Gold 6g at around 22C) ; it took around 20 hrs to get active and krausen was very thin (about one inch maximum) and had already subsided by this morning.(I pitched at Midday yesterday and view it at 10am this morning).

It was pitched at 22, has it now dropped to 5 degrees?

QldKev