Topic: Steam distillation, essential oils, KD, and "What do we know about oil in BIRs"

[Peripatetic Phil]

I have been following Jerry M's thread on "What do we know about oil in BIRs ?" with interest, but felt that there was nothing I could usefully contribute until I adopted as my bedtime reading Dr J S Pruthi's Spices and Condiments, on the recommendation of Ajoy Joshi.  What I learned from Dr Pruthi is that the majority of essential oils are extracted by steam distillation, and a little research disclosed that during steam distillation the oils are often yielded at lower temperatures than they would be if the spice were heated dry.  This led me to think about Kris Dhillon's methodology, which is radically different from that which is most commonly recommended here : whereas much of CR0's current thinking is that one needs to virtually "cremate" the spices in oil and perhaps a little tomato paste, Kris's method requires the spices to be added to a boiling stock that is 95% base and only 5% oil.  And whilst I know that not all CR0 members accept that Kris's methodology leads to real BIR, IMHO it does, and it is the method that I use preferentially and reliably, all other methods having led to too many failures in the past. 

So, what is the connection between steam distillation, Kris Dhillon, and Jerry's quest to learn "what do we know about oil in BIRs" ?  Well, it seems to me that Kris Dhillon's methodology is, in fact, well-disguised steam distillation : disguised because the essential oils are not condensed and recovered, as in lab distillation, but rather are yielded during the 10 minutes or so for which the sauce is heated, and are then recovered in the layer of oil that forms on the surface of the curry.  This might also explain why Kris recommends at least two different heat settings : high heat for the chillies, lower heat for the cumin and fenugreek (different essential oils being driven off at different temperatures).

And so it seems to me that, if Jerry has not already done so, he might consider trying to make his spiced oil by heating his "chef's masala" not just in oil, but rather in an aqueous base with a sufficient excess of oil to ensure that all the essential oils are either absorbed into the base or collected in the oil (i.e., rather than there being so little oil that there is a risk that some essential oils may be driven off and just sucked up by the hob extractor, which would be a terrible waste). 

What do Jerry, and others, think ?
** Phil.

[Stephen Lindsay]

Phil, another interesting post from your good self and I am responding to your question at the end of the post.

Given that most chefs don't scientifically or empirically test their cooking methods (heston being the most obvious exception) I wondered when you said "well-disguised steam distillation" if you mean KD has done this by accident rather than design? I would have imagined if it was by design that she would have mentioned this as a cornerstone of her cookery methods? Just a thought.

I also wonder if the same claim could be made for the Taz base which of course differs from the norm in that there is no oil added and no pre-frying of spices in the initial stage. Everything is basically just chucked in; base, tom puree, spices etc. and reduced. The other thing about the Taz base is that there is no need to use incendiary levels of heat, you can reduce quickly or slowly depending on your preference (I choose to do the latter - less mess and I'm in no hurry).

Perhaps one important difference with the Taz base is the amount of oil, which is much greater than other bases. Nevertheless the spices are not simply being fried in oil. When observing the Taz base reducing whislt cooking a curry sauce you can see there is some frying going on but as the base also contains water, the spices are being simmered whilst the water evaporates. Maybe the Taz works in a similar way to what you suggest is happening in KD's base?

[Peripatetic Phil]

Given that most chefs don't scientifically or empirically test their cooking methods (heston being the most obvious exception) I wondered when you said "well-disguised steam distillation" if you mean KD has done this by accident rather than design? I would have imagined if it was by design that she would have mentioned this as a cornerstone of her cookery methods? Just a thought.

Not exactly "by accident", more "by following the received wisdom of her own family and community", rather than by setting out to emulate in the kitchen the processes that normally take place in a laboratory or commercial premises for the production of essential oils.  In other words, I believe that Kris does what she does because it works; she may also understand the scientific basis, but such an understanding would be rare amongst chefs (as you yourself have observed, above) rather than common.

In other words, the "well-disguised" was not meant to imply an act of volition but rather a simple fact.

** Phil.

[George]

What do...others, think ?

I think it's highly unlikely that Kris was thinking of steam distillation but simply takes the view that it produces good results to cook spices in a mix of oil and water. It sounds like it works for you, too.

What does Dr Pruthi's book say about steam distillation? How are oils extracted by this method in industry or anywhere? Could it be scaled down and tried at home?

[Peripatetic Phil]

What do...others, think ?

I think it's highly unlikely that Kris was thinking of steam distillation but simply takes the view that it produces good results to cook spices in a mix of oil and water. It sounds like it works for you, too.

Yes, I tried to explain in my follow-up post that I wasn't setting out to suggest that Kris is consciously re-creating a laboratory process in the kitchen, but that empirically that is (in effect) what she is achieving.

What does Dr Pruthi's book say about steam distillation? How are oils extracted by this method in industry or anywhere? Could it be scaled down and tried at home?

I'll address that later : off to the local pet show now

** Phil.

[Malc.]

Can I refer to my comments in the following post: http://www.curry-recipes.co.uk/curry/index.php?topic=4407.msg40691#msg40691

[Peripatetic Phil]

What does Dr Pruthi's book say about steam distillation? How are oils extracted by this method in industry or anywhere? Could it be scaled down and tried at home?

This is perhaps as good a description as any : probably beyond the reach of most erstwhile chefs, unless they have access to a decent analytical laboratory setup.

Thanks also for your contribution to the thread, Axe : are you willing to offer any observations on similarities between the two approaches ?

** Phil.

[George]

This is perhaps as good a description as any : probably beyond the reach of most erstwhile chefs, unless they have access to a decent analytical laboratory setup.

Many thanks for the link to the excellent description of what's involved. I'll look into buying the flasks and other kit, as well as the legality of buying ether. Perhaps it's some kind of controlled substance, given it could also be used to knock someone out!

[Peripatetic Phil]

Many thanks for the link to the excellent description of what's involved.

You're very welcome, George.

I'll look into [...] the legality of buying ether.

I've never had any problem buying solvent ether, but your local friendly pharmacist is unlikely to sell you anaesthetic ether unless he knows you very well !  What the chemical difference is between solvent ether and anaesthetic ether I don't know : it may be just a question of purity, it may be more fundamental.

** Phil.

[JerryM]

Phil,

many thanks for taking this effort - really appreciated.

i know i don't have the full picture and as Razor has effectively spotted - i've been guessing my way through the oil question. guessing meaning that i have no access to the inside world of BIR.

there is a lot to take in on what you've presented.

1st and very important for all members - the heat question on spices - spices are very delicate and burn at 120C. the "singe" terminology was not intended to imply cremate. it's the associated quench that's important to instantly stop the cooking further. for info i still take pan off heat after garlic/ginger fry to add 60ml of base, the puree, the spice. then mix and return to heat until the water has almost gone. it's better to stop earlier than to cook to much as there is very little improvement in spice taste once the fry in water is underway.

back to the main topic. i agree with your findings totally.

i have tried the clear stock identified by axe (and parker21) which we now know as Akhni. i use the method to make pilau rice if i want top notch result (rest of time i just add some of the chef garam). it's suprising how well the spice infuses into the water.

for me it's the oil that makes BIR. after reclaiming oil (ie making it as part of the base as you suggest) for along time now i feel it gives the best of both world - the whole spice gets into the oil and into the base (effectively akhni). this spice has potential for significant impact on the final curry.

the essential oil is the strongest flavour provider and it can't dissolve in water. hence the weakness in solely relying on akhni.

the test oil that i've just made did taste good but lacked strength. my plan on increasing the strength is to recycle reclaimed oil through successive bases.

your post raises a doubt - could purchased essential oils be in use in BIR's. this for me would produce the strength and zing that i've experienced in BIR oil that so far i've not got near at home.

ps for me KD knows her stuff. i feel she and others are restricted by the commercial barrier.