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Temp and activity

PostPosted: Tue Apr 08, 2014 8:08 pm
by flamehawk
I have two batches on the go right now

Put down at the same time. One at 35deg and the other at 32deg

The one at 32 has double the co2 output and the only change in the recipe was to add some malted wheat.

Is the wheat assisting in some way or is 32 a better temp

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 8:50 pm
by kelbygreen
did you mash the malted wheat to convert the sugars? At a guess the wheats added more nutrient or the fact yeast is living and will do its own thing. To have 2 ferments identical you need a lab setting and have everything exact the same otherwise it will act a little different.

No yeast expert but there is prob 1000 reasons why it might be different but yes temp can be one of them, also I wouldnt be pushing yeast much higher then 30 deg anyway as it can stress them and they will produce different flavours and usually really unwanted ones.

My first beer I brewed I read on forum and went to the HBS got all the gear and asked him if it was to hot to brew. He said no its 35+ it will just ferment faster. That it did 3 days later was done :clap: bottled it waited cracked my great creation :ymsick: tasted like some one done a burn out scrapped the rubber off the road and dumped it in the fermenter :laughing-rolling:

Few morals learnt there. 1 dont believe the HBS when the forums are saying ferment at 18 deg and 2 well yeast make beer taste like crap when fermented high :roll:

For distilling we usually use bakers yeast this is a higher temp tolerant yeast as it is made to activate around 25+ to create co2 to raise the bread but we dont do that so use it to convert the sugar :P still pushing it to high I would be worried, though not sure the affects of it at high temps have always kept things on the cooler side since my first experiance :))

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 9:01 pm
by flamehawk
I was reading a thread the other day on this forum a guy was brewing at 38deg. Rum if I recall

What do you mean by mashing the grain. I simply boil it for an hour???

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 9:21 pm
by kelbygreen
malted grain (if its home brew shop kind) needs to be mashed to convert the sugars. So to do this the grain has to be crushed first then you have to soak it in like 65deg water for well 30mins will do it but usually a hour. But if its just to add colour and little flavour (like a caramalt) alot of guys steep in boiling water but it extracts tannins.

Mashing is a pretty complex thing. For what your doing by the sounds of it, it wouldnt be needed but instead of boiling I would be steeping it at 60-70 deg for 30 mins least you will get some conversion out of the grain

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 9:34 pm
by Yummyrum
flamehawk wrote:I was reading a thread the other day on this forum a guy was brewing at 38deg. Rum if I recall


Yes I did :handgestures-thumbupleft: ....for Rums it works great and the flavours are better at higher Temps ...for other washes ,maybe not .

I do agree with Kelby that trying to do Identical washes is hard .There are lots of variables start temp , slight variations of ingredient , slightly different aeration times Etc .I have been doing 2x washes for a while now with TPW and WBAB and even at same temp ( side by side in the same corner of the Room) ,there will be differences in Final SG ,ferment time and clearing between washes .and yes I try to keep these under 30 degC for this type of wash

However as a general rule .higher temp = faster ferment

I think you need to repeat this sort of thing several times to gauge any variations. :-B.....but you are a man after my own heart .love your work :handgestures-thumbupleft:

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 9:44 pm
by flamehawk
I am going to drop the temp to 32. See if I can get an increase in co2.
After 24hours I'll add wheat and see what happens.

I like to experiment with all this stuff!

The wheat was ground or milled. It was stored whole and as you buy it he shoves it into some blender/grinder widget.

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 10:34 pm
by Sam.
flamehawk wrote:I am going to drop the temp to 32. See if I can get an increase in co2.


Are you relying on an airlock for your CO2 production rates?

A SG reading may be more helpful. :handgestures-thumbupleft:

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 11:03 pm
by flamehawk
Yeah I was relying on the airlock. Would that not be an indicator?

What would I be looking for on SG

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 11:08 pm
by kelbygreen
air lock is no good if the vessel is not 100% airtight which they usually are not. never gauge fermentation on airlock its so false and wrong. I use glad wrap or a loose fitted lid as airlocks are over rated and give you no indication of fermentation or if its finished.

only need a slight leak in the seals and airlock may not work at all and people think nothing is happening when it is. Forget the airlock and just worry about the wash :handgestures-thumbupleft:

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 11:19 pm
by Sam.
kelbygreen wrote:air lock is no good if the vessel is not 100% airtight which they usually are not. never gauge fermentation on airlock its so false and wrong. I use glad wrap or a loose fitted lid as airlocks are over rated and give you no indication of fermentation or if its finished.

only need a slight leak in the seals and airlock may not work at all and people think nothing is happening when it is. Forget the airlock and just worry about the wash :handgestures-thumbupleft:


:text-+1: your specific gravity reading will tell you exactly where your ferment is at :handgestures-thumbupleft:

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 11:28 pm
by flamehawk
Thanks guys.

Re: Temp and activity

PostPosted: Tue Apr 08, 2014 11:30 pm
by Yummyrum
While the airlock gives an apparent visualization of activity ,it is nothing more than that .

Specific Gravity measures the "thickness" of the wash .A bucket of Water has a specific Gravity of 1.000 at 20 deg C .

As you add sugar ,it gets thicker and the SG rises...tables will allow you to calculate the amount of alcohol you can expect from how much sugar is present as measured by the SG.

A typical Sugar wash will ferment out to below 1.000 or around 0.990 or there abouts ...at that point it will go no further and is considered finished

As SG is simply a measure of the thickness of a liquard , it does not take into account other unfermentable stuff .This is where Rum makers using Mollases which is only 50% fermentable get confused .A Rum wash may start at 1.110 and finish at 1.050 ...which is perfectly OK ..the rest of the thickness is due to cellulose and other shit in the mollases.

It is the change in SG which is important , SG is fairly accurate at the lower ( close to 1.000 end of the scale ) ...however there are slight inaccuracies in SG which occur at the upper end which can be accounted for if this is where you spend your time :roll:


Repeated measurements will allow you to gauge what is Normal :handgestures-thumbupleft:

You just have to be careful when taking SG readings .Do not keep opening your fermenter as you expose it to infection every time ......if it has a tap,draw off a sample ....just don't do it every day .You need around 100 ml each time ,so the level soon drops if you are an eager beaver :-D

Actually this is where the combo of an air lock and SG readings is helpful .While the airlock is busy popping off don't waste your time sampling .When the Pop-off slows down to a stop .ish ...start to have a look

Re: Temp and activity

PostPosted: Wed Apr 09, 2014 9:28 pm
by Boots
:text-thankyoublue: Hi all, I've been brewing in Brisvegas all summer, keeping my wash in the garage. The average temp is around 30, and this has been working very well. As we move into winter my garage temp will fall and so will the activity of the yeast. I'd just like to know what other guys are doing in the colder months to keep the wash warm?

Re: Temp and activity

PostPosted: Wed Apr 09, 2014 9:50 pm
by SBB
.G'day Boots, there are a number of ways you can go. Fish tank heaters, Heat pads from home brew shops, electric blankets and even wrapping an old Doona or quilt around your fermenter are some of the methods people use. With most yeasts its more important to keep a constant temp rather than one specific temperature. While your here it would be good if you could pop over to the forums "Welcome Center" and introduce your self to everyone.

Re: Temp and activity

PostPosted: Wed Apr 09, 2014 9:51 pm
by kelbygreen
I thank you for asking this in a already created thread to start with :clap:

Well there are a few options you can use some, I will run threw a few I use.

easiest is to get a blanket (I use insulation bats) and wrap the fermenter up in them. You have to remember yeast will heat the wash as it ferments so if you pitch the yeast at a warmer temp and wrap it up the thermal mass of the fermenter and the yeast fermenting will keep it warm, In brisbane I wouldnt go much over this unless its truly needed.

I do the above for washes but have a heat pad I jamb in the layer and turn on for a couple of hours a night to boost the temp but I am in newcastle and it may not be needed there.

Another option is a heating pad/belt as I said above but wrapping it to prevent heat lose is also as important I wouldnt run it 24/7 but just at night when it gets cool and turn off when you go to bed or what ever works

One more if you have a dead fridge or a spare one in the shed that the fermenter can fit in sit it in there again pitch the yeast around 30 deg and close the door don't be opening it thats the biggest thing here as once you open that door all the stored heat just goes straight out so be confident that its working and open it when the days at its warmest if you have to, not at 4am when its -2 lol

one other thing I done (more beer brewing as you want a stable temp) is ferment in a fridge, have temp control hooked up to the fridge for cooling and have a heat pad or ceramic reptile light hooked up inside for heating. I used to have it set to .3 deg variant but usually used heating or cooling not both at once as by the time it shuts off it will keep cooling or heating and you will be left with the fridge and the heater going one after the other to try to keep it in range. some use a 750ml bottle to put the prob in as it will have quicker response then 30lts and it all equals out in the end.

can be as simple and as complicated as you like :P

Re: Temp and activity

PostPosted: Thu Apr 10, 2014 10:46 am
by Boots
Thanks fellas, I think I'll be wrapping the wash in a blanket first and see how i go from there,
Also, I have put down my first TPW (your recipe) yesterday and this morning I'm not seeing any obvious signs of activity. Normally I use Turbo Yeast and it kicks almost straight away. I'm thinking the bakers yeast is too old, I bought it during the Brisbane Floods back in 2012 when we had a bread shortage. So it's probably in-active now. Can't wait to try some spirit with your wash recipe.

Re: Temp and activity

PostPosted: Thu Apr 10, 2014 12:46 pm
by Yummyrum
Boots, that TPW sgould be going off its head by now.
You probably are right about the yeast.Get some new stuff in there ASAP and don't forget to aerate the wash with a paint stirrer in a drill.You need this to start fermenting now.

Re: Temp and activity

PostPosted: Thu Apr 10, 2014 1:20 pm
by SBB
I reckon it will go even without the stir.

Temp and activity

PostPosted: Fri Apr 11, 2014 6:25 pm
by Dusty_ben
Got the same problem
ATM. Two 25l batches of gen4 macrum. Both put down on same day. One in a fridge set at 30c. On in spare room which is at 28 or 30c every time I check it. One in fridge is on 1100sg. Other one is way of the end of the hydrometer. Maybe 1400. Might swap positions

Re: Temp and activity

PostPosted: Fri Apr 11, 2014 6:35 pm
by kelbygreen
gen 4 in a rum it is most prob the PH issue at a guess. Or you pitched to high and killed the yeast?