Why does potato gratin taste cheesy?

[hawthorne]

There’s no cheese (in mine at least) but it tastes distinctly cheesy. Sure it’s got milk and cream and salt in it, but other things have those and don’t seem to taste cheesy. It’s not a bad thing; I’m just curious.

[Contrapuntal]

I’ve never heard of a gratin *without *cheese. Huh.

[An_Arky]

Yeah, are you thinking about Scalloped Potatoes?

[hawthorne]

@An Arky

Yeah, are you thinking about Scalloped Potatoes?

Ah, didn’t think to check the language thing. Apparently so:[

A potato gratin with béchamel sauce is one of the most common of gratins and is known by various names. In the midwestern United States, the dish will be referred to as scalloped potatoes.

](Gratin - Wikipedia)

[Lissla_Lissar]

There’s an essay about that phenomenon in It Must Have Been Something I Ate, by Jeffrey Steingarten. I think it’s called Scraping by. Anyway, as I recall, when you heat up the cream to a specific temperature (reached during the baking) it starts to break down, separating into butter and a curd substance, which gives it that cheese taste. See the book for further details.

[hawthorne]

Thanks Lissla Lissar. Searching with your information I get [

The miracle of the best gratin dauphinois, he says, “is that they acquire a rich and cheesy taste even when they contain no cheese at all! That’s why I consider sprinkling parmesan or gruyère on or in a gratin dauphinois to be a gross and pitiful imposture, an admission of failure.”

He is right; but why? Steingarten is not one to let a miracle rest. He rings a friend in France and another in Atlanta. I am in the middle of reading their explanation (to do with fat, protein and solubles forming like cheese curds) when he arrives at our table.

](The Times & The Sunday Times: breaking news & today's latest headlines)which is enough to suggest I want the book.

[Lissla_Lissar]

You’re welcome. Jeffrey Steingarten is an extremely fun and interesting writer. You won’t regret getting the book.

[hawthorne]

I got the book and it looks up my street. For anyone interested, here’s the bit from Harold McGee quoted by Steingarten on p 164:

The potatoes absorb water from the liquid, which also evaporates, so you get a concentration of the fat and protein and solubles, much as you would in fresh [cheese] curds. Then the heat will encourage rapid reactions, some of the products of which will resemble the products of slow ripening [in cheese]. They have found pyrazines (typical of Maillard browning reactions) in Gruyere, for example.

So it’s two steps - the first is kind of like making ricotta with the potatoes taking up the moisture to leave curds. I guess this is why whisking in a little flour into the milk prevents what my cookbook calls a curdled appearance - they’re pretty much literally curds. The the cooking happens to produce a reaction much the same as aged cheese. And indeed, sniffing my leftovers confirms that it smells not just generically cheesy but quite like mid-aged Gruyere.

[Uga_VI]

@hawthorne

Ah, didn’t think to check the language thing. Apparently so:[url=http://en.wikipedia.org/wiki/Gratin]

No, your language is fine. Though some people in the US call them “scalloped potatoes”, the definition & common usage of Gratin in the US is the same as Australia, England, France, etc.