Topic: filtering oil

[Peripatetic Phil]

How did you extract the spiced oil in the first place, Goncalo ?  It looks very much to me as if the lower layer is aqueous, whence the fact that the fresh (odourless) oil floats on the top.

** Phil.

[goncalo]

I simply sieved it with a relatively fine sieve. Is there anything I can do/should have done to make it "blend" properly?

[Peripatetic Phil]

I simply sieved it with a relatively fine sieve. Is there anything I can do/should have done to make it "blend" properly?

Hmmm, then I don't think you started with spiced oil in the first place !  I think you started with a spiced emulsion, which  you would then have needed to heat gently and then leave to rest undisturbed until the oil had settled out on top.  You should then have poured off and reserved the spiced oil, leaving the aqueous residue behind.

** Phil.

[goncalo]

and can I still do the emulsion at this stage?

[Peripatetic Phil]

and can I still do the emulsion at this stage?

Should work fine.  Heat gently in a saucepan, stir well, then decant (ideally into a heatproof transparent Pyrex ^(R) jug), leave to cool, then carefully pour off the spiced oil from the top.

** Phil.

[goncalo]

I'm a bit confused Phil. Any chance you could break it down a bit further?
What should I expect to see at each stage?

update: I can see some froth building up on top of the oil which is heating up slowly. Should I try to spoon the froth out into the pyrex?

[haldi]

It's difficult to create this takeaway oil at home
Two takeaway places, that let me in their kitchens, just ladle off the oil from their cooked curry gravy into an large empty white tower tomato puree cans
So all the gunk drops to the bottom
They spoon off pure cooked oil from the top

Then when they make the next curry gravy, any remaining oil and the stuff at the bottom of the can, goes into the curry gravy pot
And you should smell this when they do
This , for me, is what makes takeaways taste and smell so wonderful

[Peripatetic Phil]

I'm a bit confused Phil. Any chance you could break it down a bit further? What should I expect to see at each stage? update: I can see some froth building up on top of the oil which is heating up slowly. Should I try to spoon the froth out into the pyrex?

Sorry, wasn't intentionally cryptic -- let me try to be even more clear, with apologies if you already know/understand anything that follows :

The most important point is that oil is lighter than water; second is that in the presence of ground spices, water and oil when mixed together tend to form an emulsion.  You need to persuade the emulsion to break down so that it liberates free spiced oil.  So.  You put everything into a saucepan, heat gently (it does not need to boil) and stir thoroughly so that everything mixes together (the emulsion); then, while it is still hot (very important) you pour it into a tall clear heatproof (usually Pyrex^(R)) container so that you can clearly see the line of separation between the oil (at the top) and the solid and aqueous matter (at the bottom).  You then leave it undisturbed to cool.  When cooling is complete, the (spiced) oil will be at the top, the solid and aqueous matter at the bottom.  You then carefully decant the (spiced) oil from the top, which is the part you want, and do what you like with what remains.

Oh, and no : the scum (frothy stuff) that forms on the top contains particulate matter by definition, so it has no place in your spiced oil.

** Phil.

[Naga]

You could always siphon the oil off the top using some cheap clear plastic tubing from an aquarium or home-brewing shop.

[goncalo]

Thanks Haldi, Phil and naga for your tips. Also, I didn't meant to say you sounded cryptic, Phil. I suppose I just never had an interest in chemistry to begin with

However, I was wondering whether if I'd heat it over 100C, wouldn't the aqueous content form bubbles, rise to the surface and form a steam cloud, in other words, evaporating the aqueous content.