Gypsum

[Rossa]

Without going online where can I pick up gypsum in the Dublin area?

[Eoin]

I got mine in one of the Chinese supermarkets in town.

Pretty sure it was in the one on Drury Street.

[UpsidedownA (Andrew)]

One question I've always had is how close gypsum is to plaster of Paris or even just plaster really. That would surely be the cheapest source if the plaster is pure enough.

[Spud395]

When we're on the subject, how about sources for calcium cloride?

Anyone find a different source for that other than online?

[Eoin]

Gypsum plaster (plaster of Paris)

Gypsum plaster, or plaster of Paris, is produced by heating gypsum to about 300°F (150 °C):[1]

    CaSO4·2H2O + Heat [ch8594] CaSO4·½H2O + 1½ H2O (released as steam).

When the dry plaster powder is mixed with water, it re-forms into gypsum.

http://en.wikipedia.org/wiki/Plaster

[Will_D]

Most of the HB online stores stock Calcium Sulphate and Calcium Chloride to Food Grade Specs. ( several €'s per 100's of grams )

If you want to add spoonfulls of plaster of paris or the pink, Gyproc finishing plaster ( several €'s per 25Kgs ) then so be it!

Will

[Eoin]

Most of the HB online stores stock Calcium Sulphate and Calcium Chloride to Food Grade Specs. ( several €'s per 100's of grams )

If you want to add spoonfulls of plaster of paris or the pink, Gyproc finishing plaster ( several €'s per 25Kgs ) then so be it!

Will

I'd not use plaster of paris in stead of gypsum myself, regarding the food safety of it. The bag of stuff I got in the Chinese shop over two years ago is still going strong and I'd use one tsp per brew.
It's really really good at helping the hot break and is great if you like to skim the boil as it creates a large amount of skimmable stuff, as a biab brewer I feel this skimming is pretty much essential to producing good beer.

[Eoin]

I just had to check it now and the Chinese use gypsum in producing Tofu, so if you're as curious as me.....