Using oven to maintain temps

[AJ_Rowley]

Hey guys,

Would anyone know if is possible to use my oven to maintain mash temperatures? I have a Hotpoint fan assisted oven, and its lowest temp is 80°. I use a 10 litre stock pot and with such a small batch temps don't hold that well even when wrapped in everything but the kitchen sink.

Also could this be used to maintain temps for a sour mash?

Cheers
AJ

[Will_D]

I seem to remember that the very first NHC Brewing champion used just that method for his stout!

[Parky]

Hi AJ,

This is pretty much the method I use for my all-grain batches, and it's worked pretty well so far for maintaining any particular mash temperature I'm aiming for. Some pointers from my own experience -

1. Leave at least 1L headspace in the stockpot in case the mash goes cool and you need to top up with boiling water.
2. Stir the mash every 10-15 minutes to distribute the heat evenly and ensure all the grains are exposed to the water.
3. After stirring check the temperature and adjust up or down as required - this way the temp won't go off target for too long.
4. Sounds obvious, but keep the stock pot lid on while mashing.

That's all fine for producing a sweet wort, but looking at the minimum temp of your oven it may be a bit high for a sour mash. If I'm understanding correctly you'll be adding a lacto culture to the wort, and this is generally done at temps between 35 - 50^oC, with the temp held there for a few days. Despite any efforts to insulate your stock pot the temp of the sour mash will inevitably drop over time, and you could use the oven to give it a temp boost to keep it within a given range. Maybe putting it in the oven for 30 minutes twice a day might do the trick, but try not to tip the temp above 54^oC.

Hope it turns out well 

[AJ_Rowley]

Thank you parky, good to know.

@Will I vaguely remember reading something about that

[shweeney]

I did my first BIAB at the weekend and this is exactly the method I used - brought the pot to mash temp on the stove then put it in the oven on low heat.  The dial on the oven starts at 50 and it isn't that easy to see where 66 is so I put a meat thermometer in beside the pot to monitor the temp.  An hour later the mash was still dead on 66.  This was with a 19L pot with about 16L of water+grain in it.

[UpsidedownA (Andrew)]

Fair play to you guys for giving this a try. I'm amazed it's possible. Home brewers are truly the champions of the brewing world when it comes to innovation.