Steep in a Thermos flask?

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Racehunter

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I am going to steep a small amount (150g) of crystal malt to add to a Cooper's AuPa kit but wondered if I can achieve this in a Thermos flask?

My thinking is that it should hold the 75°C temp for 30 mins rather than maintain that over a flame?
 
I am going to steep a small amount (150g) of crystal malt to add to a Cooper's AuPa kit but wondered if I can achieve this in a Thermos flask?

My thinking is that it should hold the 75°C temp for 30 mins rather than maintain that over a flame?
Certainly worth a try but what size is your flask and the reason I ask is that your grain shall swell as it absorbs water to around twice its size and you will also lose the same liquid as too weight of grain.
I'm assuming you'll fill a kettle then preheat the flask so as to prevent heat loss when adding your grain then wait until the kettle has cooled to temperature then soak for 30 mins.
It's also dependent on what size of a batch your brewing for and TBH you'll probably spend as much time preparing and stabilising temps.
Heat in a saucepan, put on the lid and wrap in a towel and it will be fine though the flask idea does intrigue me as I have a 1.5l flask... 🤔🤔
 
I have a large 1.8L flask, so expansion shouldn't be a problem. I use a similar method to cook hempseed for fishing and that always produces consistent results. My kettle is temperature adjustable so I would heat 1.5L water to 75°, use a small volume to heat the flask, then in with the crystal malt and 1L water, lid on and leave for 30 mins.

I will give it a go and report back
 
Yes I seen that but I'm wondering what he wants from the crystal malt..and if he is copying a recipe from somewhere.
I ask as there's a few recipes on the Cooper's site that cold steep some grains over night,whereas holding the crystal at 75* sounds more like a hot end mash.
 
Yes I seen that but I'm wondering what he wants from the crystal malt..and if he is copying a recipe from somewhere.
I ask as there's a few recipes on the Cooper's site that cold steep some grains over night,whereas holding the crystal at 75* sounds more like a hot end mash.
I C what you mean...
 
Hi @Racehunter and @Gerryjo

As a general rule of thumb, for mash-tun sizing, dry grain displaces around 0.75lts/kg of water ... so 150g of grain in say 375ml of water (2.5 lts/kg) will end up as just under a half a litre of mash ... I occasionally do a mash just a little bigger than this in a 1 ltr thermos to make around 1lts of (AG) starter wort when I don't have any DME.

But for steeping crystal malt, like Clint says, you really don't need to worry about steeping temperature nearly as much for mashing ... cold steeping, or steeping in water at/around 65C won't make that much difference ;)

Cheers, PhilB
 
Hi @Racehunter and @Gerryjo

As a general rule of thumb, for mash-tun sizing, dry grain displaces around 0.75lts/kg of water ... so 150g of grain in say 375ml of water (2.5 lts/kg) will end up as just under a half a litre of mash ... I occasionally do a mash just a little bigger than this in a 1 ltr thermos to make around 1lts of (AG) starter wort when I don't have any DME.

But for steeping crystal malt, like Clint says, you really don't need to worry about steeping temperature nearly as much for mashing ... cold steeping, or steeping in water at/around 65C won't make that much difference ;)

Cheers, PhilB
Interesting as I would never have thought to try that but will certainly keep it on my list for handiness 👍
 
The 30 minute soak at 75°C ish followed by a sparge of the grain with another litre of hot water was suggested by terrym, who also said that the liquid should be boiled for 15 minutes to sterilise it before cooling and adding to the wort.

This is an experiment using Cooper's AuPa as the base, the adding the steep liquid and 500g of dextrose and 500g of DME. I will then split the volume between 2 FV's of 11L and use a different hop tea in each. Just wanting to add colour and body to the kit and different hop qualities
 
Hi
The 30 minute soak at 75°C ish followed by a sparge of the grain with another litre of hot water was suggested by terrym, who also said that the liquid should be boiled for 15 minutes to sterilise it before cooling and adding to the wort.
... and I'm sure @terrym will come along and disagree with me if he thinks I'm wrong on this, but ... steeping crystal malt (and/or cara-malts, roasted malts ... stuff generally know as "speciality malts") isn't that temperature dependant ... when mashing base-malts maintaining the temperature of the mash is important, because you're looking to have particular enzymes work in particular ways ... but steeping isn't mashing, the kilning/roasting of speciality malts have denatured (making them ineffective) the enzymes in those grains, and all you're looking to do when steeping is dissolve some of the sugars and colours in those speciality malts, into the water you're steeping them in ... if you've ever tried to get sugar to dissolve into water, you'll know it dissolves quicker if warmed up, but given time, it'd get there eventually even if using cooler water :?:

Cheers, PhilB
 
Hi
... and I'm sure @terrym will come along and disagree with me if he thinks I'm wrong on this, but ... steeping crystal malt (and/or cara-malts, roasted malts ... stuff generally know as "speciality malts") isn't that temperature dependant ... when mashing base-malts maintaining the temperature of the mash is important, because you're looking to have particular enzymes work in particular ways ... but steeping isn't mashing, the kilning/roasting of speciality malts have denatured (making them ineffective) the enzymes in those grains, and all you're looking to do when steeping is dissolve some of the sugars and colours in those speciality malts, into the water you're steeping them in ... if you've ever tried to get sugar to dissolve into water, you'll know it dissolves quicker if warmed up, but given time, it'd get there eventually even if using cooler water :?:

Cheers, PhilB
@Racehunter and @PhilBrew
You are both correct as far as I'm concerned.
Speciality grains like crystal malt don't need mashing because the starches in the original malt have been converted to sugars by the kilning process, so a steep to extract those sugars is all that is required. I would have suggested a 75*C steep since that hastens the sugars leaching from the grain. Any higher than 75*C may start to leach out tannins from what I understand. However there is no reason why lower temperatures cant be used, it just takes progressively longer that's all.
 

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