Effect of Yolk or Buttermilk in Pie Crust?

[Martin Baadsgaard]

Hello, just out of pure curiosity, does anyone know the practical and/or theoretical reason to use buttermilk or egg yolks in a pie crust?

I do not make nearly enough pie to test this through,

but initially I didn't see much difference in using egg yolks, compared to same recipe without.

Buttermilk crust also tends to be a more crisp kind of crust, but it doesn't seem to be because of the buttermilk especially.

Maybe it is for emulsifying? But how and why? Or maybe it is for browning?

Hope someone has a little bit of knowledge and experience on this matter

[AnnieWilliams]

I think with egg yolks, the purpose is to have the fat to protect the flour from becoming over mixed. I think the acid in the buttermilk does the same. Usually you see vinegar in the egg yolk pie crust recipes too.

[Martin Baadsgaard]

Aaah, good point with the vinegar. Vinegar weakens the gluten connections, so it makes it more tender (In contrast to salt, btw..)

I don't get the idea with the fat though? You mean it acts as a shortener, like if you mixed in room temperature butter?

That would make sense actually...

[AnnieWilliams]

Yes, generally it coats the particles of flour and makes it less susceptible to forming gluten when water is added. Think reverse creaming when baking cakes.

[Martin Baadsgaard]

Well thankyou for the reply

I am expanding my pie crust versatility, so trying to figure out what all the parameters are good for...

[AnnieWilliams]

Martin, I went on a pie spree several months ago. I bought several books off Amazon. Pie it Forward by Gesine Bullock-Prado, The Lost Art of Pie Making by Barbara Swell, and Mrs. Rowe's Little Book of Southern Pies by Mollie Cox Bryan. The last one is my favorite. The book discusses the recipes used in Mrs. Rowe's Restaurant and Bakery. She was an elderly lady who made the best pies. And believe me, when it comes to pies, I am more inclined to learn from an elderly lady who's been baking them for 70 years as opposed to a pastry chef (no offense to the awesome pastry chefs here). She does give a yolk recipe and a couple of other recipes for crusts.

[Martin Baadsgaard]

Cool, thanks, I'll have a look into those