Showing posts with label molecular gastronomy. Show all posts
Showing posts with label molecular gastronomy. Show all posts

Monday, April 24, 2017

The Sealing of the Pot

The CC received a clay pot as a gift recently.

It was a classic meen chatti (मीन चट्टी - literally: fish clay pot). The first word is from Sanskrit (= fish) and the second most likely from the local vernacular.

Instructions were provided to "season it" but the CC needs to understand what that means so he proceeded down the rabbit hole (as he is wont to do) about what that really entails.

Clay is quite porous as a material. However, it can be fired at high temperatures after which it becomes hard. That's how bricks are made which has been known since at least Sumerian times.

Clay is also an extraordinarily poor conductor of heat.

These combined facts act as an advantage in fish cookery.

The critical point about a clay pot is that no matter how hard you try to heat it in a reasonable time (= less than five hours, for example), it's very difficult to raise the temperature of the interior of the pot to above 70°C — which is the outer limit of the temperature that fish proteins denature.

Of course, if you fired the crap out of the pot, eventually it would rise to the temperature of the flame but we're talking cooking here not cremation!

The other critical point is that if you don't raise the temperature beyond the denaturation point of fish proteins, they will stay soft independent of the cooking time. If you held the temperature precisely at a certain point, your fish would stay perfectly tender whether you cooked it for ten minutes or ten hours!

This is how airlines control food, for the record. The temperature is never allowed to get above the denaturation point of the proteins in question — chicken, beef, fish, vegetables, whatever!

The principle of clay-pot cooking is the same as that of sous-vide cooking except that it is being done in an intuitive way rather than formally. It also has a massive advantage over sous-vide in that you can fry or sear the fish and have it cook in the complex juices generated by it. You don't need to worry about the problem of precise timing either which was a useful fact in the frenetic frazzled world of yore unlike modern day times.

There's a price to be paid for this freedom. Nothing comes for free.

The pot is a complex apparatus. If you drop one of your metal pots, it'll get dented. If you drop a clay pot, it shatters and you get to start all over again. (Luckily, they are cheap but that's not the point.)

Poor conduction also goes both ways. It's really hard to raise the temperature and it's equally hard to lower the temperature. A certain boring-ness is required in the usage of a clay pot. You can't just dial the temperature up and down like a metal pot.

Much more importantly, you can't add hot water to a cold pot, or cold water to a hot pot. It will crack. The poor conduction means you cannot have the interior and the exterior at significantly different temperatures.

The seasoning of the pot is really quite simple once you grasp the concepts. You alternate boiling cold water in the pot and toss it out followed by coating it with cooking oil overnight. The water percolates through the pot and mends micro-holes in the clay and the oil conducted via the water generates enough carbon residues to plug the holes. It also generates a non-stick surface at the bottom of the pot over time (exactly like a great cast-iron frying pan.)

There are two fallacies about clay pots and since chez CC, we tend to be the analytic sort, we're going to dismiss them.

The first is that the seasoned clay pot is not porous — it absolutely is! The water inside the seasoned pot has to be going somewhere. It's not evaporating significantly at 70°C so it must be disappearing somehow. It's evaporating through the porosity of the pot. It's being wicked§ away.

This porosity created a bit of a problem for the CC in the second round of water seasoning when the pot had been coated with oil overnight. Enough oil/water was being wicked away through the porous clay that the CC's gas flame went a little crazy. It's basically a baby version of a grease fire. It was such a minuscule amount of oil that it posed no risk whatsoever but it was quite unnerving until the principles had been grasped.

The second which is really the flip of the first is the myth that you can't cook in a dry pot without water. You absolutely can as long if you want to raise the temperature above 70°C. You could quite plausibly cook the clay pot to up to 1000° C but the CC really doubts that your puny stove generates enough BTU's for that. (Your oven only goes up to 275°C!)

Remember, if you do amp up the temperature of the pot, you will not be able to add cold water to it. You must either cool the pot down and start over or heat the water to the same temperature and add it. Most cooks do the former not the later since it's too risky.

In fact, many recipes ask you to first boil stuff till the water disappears, take the fish out, and then use the pot just like a frying pan adding the fish back at the last step. (The reverse is also true. Some recipes ask you to use it like a frying pan and then add the fish and warm water a little at a time thus lowering the temperature back down.)

Let's abstract out the principles of the perfectly seasoned clay pot.

[1] With water inside, the temperature will not go above 70°C until the water disappears.

[2] The clay pot is a very poor conductor of heat.

[3] The dry clay pot will allow you to fire it up to 1000°C.

Now that we've grasped the principles, we're ready to roll.

One of the great glories of Mughal cooking is the perfectly cooked daal. This involves the denaturing of lentil proteins and some of these lentils tend to get slimy if the skins split. The clay pot is the ideal apparatus since it preserves the skin perfectly while letting the water and spices to enrich the dish via osmosis but not allowing the lentils to burst.

The truly great dish of Gujarati cooking is undhiyu (ઊંધિયું — literally: upside-down.) The Mughals totally envied this dish! It's a classic mélange of spring vegetables, complex vegetarian meatball-esque preparations, and spices cooked in a sealed upside-down (sic) pot in the dying embers of a fire overnight at low heat. Same logic goes for long-term low-temperature cooking and the denaturing of the proteins.

If you go to North India during winter, you'll find yogurt served in clay pots. The clay pots are being used for two purposes — heat preservation and water-evaporation. Even in the cold temperatures of the North-Indian winter, the clay pots retain the heat of the warm mixture of milk and bacteria and wick away enough water to make the yogurt rich and delicious.

So this device which is at least 20,000 years old (based on Chinese excavations that date back to 18,000 BC) is truly a magic apparatus. It just requires a little understanding.

We're just the latest in a truly ancient lineage.


† You can verify this quickly and empirically by sticking a finger for less than a second into the water that has been boiling in the clay pot for an hour. Nothing much will happen. If you stuck your finger in real boiling water for even less than a second, you would get second-degree burns!

‡ The CC will not bore you with the details but roughly speaking in an environment with no air-flow (e.g. your exhaust fan) the evaporation rate is linear in the temperature differential between water and air for temperatures around 100°C. Estimating your house to be about 25°C (80°F), you are only getting roughly 60% of the evaporation of boiling water. The rest of the water has to be going somewhere!

§ You can test this by covering a pot and heating water in it. It will never boil but soon much of the water will be gone.

¶ The clay pots have the advantage of porosity. The yogurt bacteria are sitting in there and they help develop the culture implicitly particularly if you make yogurt every day or week in the same pot. (The clay pots that they use are small. Individual use, one might say, in modern parlance.)

Friday, April 3, 2015

The Epitome of Simplicity

The name of Ferran Adrià will forever be linked to molecular gastronomy but very few know that is a passionate advocate and practitioner of the simple perfection of Catalan cooking.

The freshest of ingredients, minimally touched, delivering magic on the tongue.

Here's one of his simplest recipes (and the CC paraphrases):
Scrape a vanilla seed into a bowl. Heat up some heavily salted water. Put fresh tagliatelle and cook for 3 minutes. Meanwhile, heat some unsalted butter in a pan, put in the vanilla scrapings at high heat. Add a splash or two of the pasta water. Drain the pasta. Toss with the sauce. Add with a lot of grated parmesan.
Some of you might have spotted the sleight of hand behind the simplicity. Fresh pasta takes some effort and it has to dry out for a few hours.

The rest is actually in the traditional sense of the word "simple".

However, the CC can attest that this recipe indeed is magic. Vanilla which is only seen in a sweet context takes on the starring role in a savory context.

Do make this. Even if you have to use dried pasta. This is ethereal.

Friday, March 11, 2011

Defending Molecular Gastronomy

The CC is aware that the world shits upon this stuff on general purpose in the name of "tradition". The CC could argue at length about why this is wrong but there's a far simpler way of arguing.

Take flaked salt, and mix it with fine olive oil.

Slice tomatoes, and drizzle the above mixture over it. Add strips of basil.

Salt is a polarized molecule. It will not dissolve in non-polarized liquids like oil. That means the crunchy salt will still remain crunchy, and not dissolve in the tomato's watery juices nor will it make the tomato "sweat".

You can use your finest fleur de sel this way, and it will work. The reason it works is science.

You haven't seen this in any book you own because they simply didn't get it.

If this were so obvious, why is this not there in Julia Child, Marcella Hazan, and the zillion others that make a fetish out of tomatoes, olive oil, and salt?

Why is this not present in four hundred years of Italian tradition?

So, fuck you, "tradition"!

Tradition, which can be useful can also be rank superstition. It's done this way, why, well because it has always been done this way. Kinda silly sometimes.

Facts and evidence (= science) matter more.

Wednesday, April 1, 2009

Molecular Gastronomy

A group of influential international chefs have sequestered since yesterday in Alicia, Spain. Their mission has been to find a more palatable term for the dreaded “Molecular Gastronomy”. The consensus seems to be leaning towards ORGASMIC, an acronym for ORganoleptics, Gastronomy, Art, & Science Meet In Cuisine. A final vote on the proposed name change is scheduled for tomorrow morning, followed by the unveiling at a press conference.

Monday, January 5, 2009

Least Counts

Whenever the CC reads a cookbook with the phrase, "This makes one cup of the spice mixture. It can be stored for future use", he rolls his eyes, and contempates ordering takeout.

Yes, we love cooking; yes, we are perfectly capable of spending hours to perfect a fine dish; and yes, we are willing to spend hours and days traveling great distances to find obscure ingredients.

But no, we do not wish to eat the same thing for the rest of the year, or even for lunch the next morning.

Shouldn't this be freakin' obvious?

So one cup of a complex spice mixture which takes an hour to make where the recipe calls for two tablespoons is a bit more than the CC's patience can endure.

What's the real problem? It's one of least counts really. To accurately render a recipe, you need to get down to fractional quantities which is not always possible.

What to do?

Scale down the recipe.

The CC has no problem down to 1/4th or even 1/8th of a tsp. He is perfectly capable of smashing an appropriate spice with his trusty pestle, keeping the appropriate amount, and discarding the rest.

However, scaling down is trickier than it sounds. To "correctly" scale down a "suitably large" spice recipe, one cannot just divide everything by 4 (or whatever.) Typically (but not always!), to do a good job, if you scale the largest stuff by 4 then you must scale the "intermediate" stuff by 3, and the smaller stuff by 2, and the smallest stuff not at all.

There is an intrinsic non-linear twist in the scaling down (the reverse for scaling up.)

Amateur chefs make this mistake all the time. They don't understand this.

And no, inspite of the CC's ultra-rational bent, he does not know why this is the "right" way to do things. He just knows empirically that this is the thing to do in many (but not all) cases.

Does the CC contradict himself? Very well then, the CC contradicts himself. The CC is small, and yet he contains multitudes.

Maybe the molecular gastronomy people would like to weigh in?

What to do after you've made the spice mix and used some but not all?

[1] Store some, and dump the rest, and call it a boredom tax. Yes, this is wasteful but eminently rational. (The spice mix will lose its potency before you ever reuse it.)

[2] Make the 1 cup version, and hand out as gifts to all your friends who will never make the recipe anyway. It will assuage your soul while it languishes in their spice cabinet, and they will toss it out at a future date. (You can short-circuit this process by tossing it out right away.)

[3] Buy a micro-scale (although it just might be cheaper to do the tossing because micro-scales are more expensive than spices. Yep, the CC is rational.)

[4] Have an array of powders some refrigerated and others not (as appropriate.) This assumes you don't live in Manhattan, London, Hong Kong, or San Francisco where space trades at a premium.

[5] Some pastes/powders freeze well. This actually works out in practice.

Anybody have better ideas on the subject?

Monday, December 31, 2007

Friday, October 19, 2007

French Classical Sauces

Escoffier may list hundreds but there are only 23.

W
O
W/S
O/W
S/W
(O + S)/W
(W/S)/W
O + (W/S)
(G + O)/W
(G + O + S)/W
(O + (W/S))/W
(S + (W/S))/W
((W + S)/O)/S
(O + S + (W/S))/W
((W/S) + (S ⊂ W))/W
(O + (W/S)/W)/S
((O + (W/S))/W)/S
(O/W) + ((G + O)/W)
(O + (W/S) + (S ⊂ W))/W
(S + (W/S) + (S ⊂ W))/W
(((W/S) + (S ⊂ W))/W)/S
(O + S +(W/S) + (S ⊂ W))/W
(O + S +((G + O)/W))/W


Key (letters): O = oil, W = water, G = gas, S = solid
Key (operators): + = mixed into, / = dispersed into, ⊂ = included into

For example, both broth or vinegar are just W, and butter is (W/O)/S.

Note that in a given formula, the multiple W's and S'es may be different.

This is the work of the magnificent Hervé This, co-inventor of the field of molecular gastronomy.

See if you can come up with examples of the above sauces, fellow gastronauts!