Pimping a Coopers Kit with a Partial Mash

[Bribie G]

In my original post I boil for an hour, but hops in at 30 minutes. The idea of the first half hour of boil is to coagulate stuff from the partial mash that might cause haze in the finished beer, then half an hour of hops.
There probably wouldn't be much difference in simply boiling for 30 minutes with the hops.

As the hops are boiled in the wort from the partial mash then the length of boil depends how bitter you want the beer. If it's a well hopped kit such as Coopers Real Ale and you are using the hops for flavour and aroma then a ten minute boil would be fine.

On the other hand if you are doing something really light in flavour such as a Cerveza kit plus some plain base malt and need a bit of background bitterness, then probably the half hour boil with a small amount of bittering hops (say Magnum or Galena) would be more appropriate as you aren't looking for much aroma, just a bit more bitterness than you would get from the Cerveza or Canadian kits. I did that myself just recently (kegged yesterday) with a "Blonde Ale" partial and a few grams of Super Alpha.

 

[Dae Tripper]

So it is just haze problems?

I am doing full extract, the 10min IPA was 230g of Amarillo for a boil of 10min so that's all the boiling I did after having the crystal grains in there for 30min at 66*c or so.

 

[Alex.Tas]

During the mashing process the S-Methyl Methionine (SMM) present in the grain will break down into dimethyl sulfide (DMS) and DMSO - an oxide variation of DMS.
Some grain contains more SMM than others which is primarily (as afar as I'm aware) due to the kilning temp of the grain. Lower temps means more SMM. Pilsner malt therefore contains more SMM than Munich for example.

DMS is a problem in beers as it has a flavour of cooked/creamed corn. All beers contain DMS, but some more than others and usually you want to reduce it as much as possible.
You can do this by boiling your wort for an extended period of time (60 min or more) as DMS is fairly volatile, which means it boils off at a low temp and is removed from your beer.
The half life during a rolling boil of DMS is 40 min so theoretically you reduce the DMS in your beer by half by boiling for 40 min, 75% after 80 min 87% by 120 min. Due to this evaporation of DMS, you should keep the lid off your boil kettle so it's doesn't just drip back into your beer.

The oxide variation of DMS isn't as volatile unfortunately and may be converted to DMS during fermentation. This is more common for cold fermenting lager yeasts. Ale yeasts if fermented vigorously can scrub some of the DMS out.
DMS can also be formed from SMM after the boil while the wort is still hot, so it's beneficial to cool the wort as quickly as possible to prevent this creating too much DMS.
I no-chill some of my beers (mostly lagers) and haven't had any issues with DMS, but I always do a 90min boil.

So, theoretically and generally speaking:

• Pils malt will give you more DMS
• lager yeast will convert more SMM into DMS during fermentation
• slower chill times post boil will increase DMS in your beer (like I said i haven;t had any issues with nochilling my lagers, but that may be due to some other reason, I'm not sure.)

ways to reduce DMS

• boil with the lid off your kettle
• boil for longer
• chill as fast as you can (also helps prevent infection and can help preserve hop flavour/aroma but i don't mean to discuss that as no-chill works very well for most people who do it, and can produce very hop heavy beers)
• use grain that contains less SMM - but this obviously isn't practical if you want to brew light lagers.
• using a vigorous ale yeast can reduce DMS in your beer

The reason you don't need to boil for 90 min with extract is because its likely been boiled for an extended period prior to packaging and the concentration stage (either to dry powder or thick gooey liquid malt) would have reduced most of the DMS for you.

That's a basic run down, hope it helps.

Edit: sorry i just read the last two posts, i didn't see them when i wrote my response. I should also add, that if you use 50% of your fermentables from kit/extract cans/powder then your DMS content would be dramatically reduced.

 

[Dae Tripper]

Thanks Alex, that was what I was after

 

[wynnum1]

Use a big pot nothing like a stove top boil over .

 

[ekul]

How does this beer compare to your AG beers bribie?

 

[Bribie G]

With the hop driven ones they are almost indistinguishable but the lighter brews such as blonde ales are definitely not as clean or crisp as an AG version, just a bit of fruitiness coming in.
As I only have one fermenting fridge I use a 60L fermenter during summer to do double batches and my "partials" are, nowadays, 75% AG and 25% da tin.

even these have a slight fruity "twang" but not bad for quaffers.

For newcomers who don't have the equipment yet for going full AG, a pimped kit is a good way of getting within striking difference.

 

[Killer Brew]

Question. Planning to do a partial in the esky today and just did an ingredient check....forgot to get any DME and LHBS not open today. Have worked out if I can get around 3kg grain in my mash (which I do have on hand) then I can get my beer up over 4% with good body.
Clearly can't do this in my esky but I do have my 15L stock pot. Plan would be to get 10L of strike water holding at around 70 degrees on the gas stove top then add the bag with 3kg of grain in it and cover for an hour. Hopefully the same setting on the stove will maintain temp around the right level for me. After that sparge and boil as per normal. Am I missing anything?

 

[Bribie G]

One way of maintaining mash temperature is to sit your stockpot on a towel and put a cardboard box upside down over it, as close a fit as possible. I've seen a guy do that with his urn using the box it came in, and he only lost a degree and a half.

Or use a doonah.

Being a smaller volume with less thermal mass you may need to do a mid mash adjustment on the stove.

 

[Killer Brew]

Interesting. I do have some thin panels of polystyrene foam i kept so could probably line a box and fit over the stockpot. One thing is for sure and that is I will be learning something!

 

[Yob]

Question. Planning to do a partial in the esky today and just did an ingredient check....forgot to get any DME and LHBS not open today. Have worked out if I can get around 3kg grain in my mash (which I do have on hand) then I can get my beer up over 4% with good body.
Clearly can't do this in my esky but I do have my 15L stock pot. Plan would be to get 10L of strike water holding at around 70 degrees on the gas stove top then add the bag with 3kg of grain in it and cover for an hour. Hopefully the same setting on the stove will maintain temp around the right level for me. After that sparge and boil as per normal. Am I missing anything?

Consider not insulating for a reverse mash and letting it drop over the hour.

Personally, if you are doing it on the stove, you could also consider a small step mash, 64 for 30 minutes, add a bit heat and stir until you get to 68.

Yum..

 

[perko8]

I've got a coopers Devils Half ruby porter nearly finished fermenting. Thinking about splitting it in secondary as I don't drink heaps of dark beer but would like to try variations..

Three things I'm thinking of:
1- Bottle a third as is.
2- add choc malt and cold steeped coffee
3 - three kg of figs to put it over.

How does that sound?

Alternatively I could hop it up to a dark ipa ish thing - boil some hops in crystal/ caramalt and cool to rack over.

 

[Gigantorus]

Other way to hold at temp when doing partial-mash is to sit your pot (with grains in a grain bag) in your oven at low temp. I do this for all my steeps/mini-mash/partial-mash.

I just pull out the top 2 shelves and run the oven at 70C (I also use an oven thermometer to confirm my oven temp). My 18Litre pot fits just perfect in the oven.

Cheers,

Pete

 

[Bribie G]

I know a lot of American BIABers do the oven thing.

 

[Gigantorus]

I got told this some time back and it's has served me well.

I've got a coopers Devils Half ruby porter nearly finished fermenting. Thinking about splitting it in secondary as I don't drink heaps of dark beer but would like to try variations..

Three things I'm thinking of:
1- Bottle a third as is.
2- add choc malt and cold steeped coffee
3 - three kg of figs to put it over.

How does that sound?

Alternatively I could hop it up to a dark ipa ish thing - boil some hops in crystal/ caramalt and cool to rack over.

Perko,

Also consider cold steeping the choc malt overnight in the fridge - it will give it a less harsh flavour and bigger choc hit. Of course you'll then need to boil the liquid to pasturise.

Cheers,

Pete

 

[Hermies]

I like the Coopers IPA kit . I usually add another 2 - 3 kg of malt mash it for an hour ( I just put it in my 19lt pot and stick it the oven for an hour and then mash out and sparge ) I mix the wort with the Coopers can and then proceed to boil adding hops as I go . Once in the fermenter I usually dry hop and then bottle once the ferment has finished .Very drinkable . In fact a stout I made with a kit and kilo got 3rd in a state comp . So you can make good beer with a can of goo.

 

[AussieBrew]

Thia is a great write up. Muchly appreciated. I'm stepping up to partial from simple kits and steeping.

 

[Hermies]

Interesting. I do have some thin panels of polystyrene foam i kept so could probably line a box and fit over the stockpot. One thing is for sure and that is I will be learning something!

You could also stick it in the oven at mash temp .

 

[Jangles]

Oh telepathic dude, I just kegged it off five minutes before you posted :lol:

It's very good indeed, in fact mate and myself are drinking the extra couple of litres right out of primary.


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There's a slight "isohop" type bitterness but I don't know what the raw kit would taste like. Mate reckons it doesn't taste unpleasantly bitter to him - more like an old time beer he used to drink. However no perceivable "kit" twang in the malt portion, very smooth indeed, and those POR and the Coopers yeast have done their trick. And it's still cloudy and flat and warm.

BTW no real need to use a mini biab, I originally used a large $4 kitchen wire flour strainer from a two dollar shop to strain the grain into the stockpot then do a sparge with an electric jug, but a wee BIAB is more handle-able.

I'd really recommend doing this to step up from kits for anyone who needs "training wheels". When I did my very first AG I kept thinking "hey this is easy, I know this".

On ya bribie , ta for sharing this , its a good next step up from the can mans out there currently like myself .

 

[Hangover68]

I'm about to do a coopers pale ale with added crystal malt and cluster hops, how much difference does altering the amount of added malt make on the final product ? ie i have 1kg so should i use all or just use 500g and see how i like it ?
I'll stick to the 10g hop addition.