Why do you use shortening in pie crust?
Isn’t it bad for you? So asks reader Victoria. Victoria, the main reason pie makers use shortening (or lard) in their pie crusts is to keep the moisture content as low as possible. Butter can be up to 18% water, and that can be a very bad thing for the texture of a crust.
We talk about gluten a lot on the site and for good reason. North American gluten can be a real pain to work with, as it’s elastic in nature and tends to make pastry tough and prone to shrinkage in the oven. Gluten is always present in flour, but it takes the addition of water to “activate” it, i.e., cause the individual gluten molecules to bond to one another in a springy network. So we try our best to minimize the amount of water in the crust, especially at the start of the recipe where we’re working the dough a lot, because agitation also helps activate gluten.
If we were French we could probably find some of their “dry butter” to use, but we aren’t, so we make do with whatever soft-firm fats we can find. Normally that’s vegetable shortening, but historically home bakers have used lard. Some country bakers use 100% lard in their crusts, but that taste can be a little “piggy” for some people, especially with a sweet pie. Vegetable shortening offers a neutral flavor and brings no water whatsoever to the party.
So I guess the short answer to the question, now that I’ve droned on for so long, is that we use butter for flavor and shortening for a flaky texture. Make sense? As for whether shortening is bad for you, I’ve never believed that trans fats are bad for you (there’s not terribly much data to prove it). However if you’re worried about that you can buy trans-free shortening now. Or, for a more home-spun answer, find some leaf lard at a local farmer’s market (it’s milder tasting than store-bought lard), render it and use it! I can tell you that lard is great for biscuits too!
I bought some butter at the farmer’s market a while back, and when I pulled it out of the ‘frig it had water on it, like sweat. I wrapped it with paper towels, later using it for a pie crust. It had a tangy flavor, and wrapping it seemed to reduce the water to such a degree that I only added one tablespoon of water. My neighbors and husband were quite happy with the results. I wonder if the water is too bound in commercial butter – maybe chop it up a bit first, then wrap it?
Hey Naomi!
That’s fascinating. I’d assume that’s condensation, but it’s possible that if the butter is really fresh you could still have buttermilk leeching out. The giveaway would be the color. If it’s white, it’s buttermilk. If it was clear it was probably condensation. Probably. 😉
Thanks for the comment!
– Joe
Hi Joe!
I’m glad you posted this because it allows me to ask about a hypothesis I’ve been thinking about for a while. For the last 7 or 8 years or so, I’ve only made pastry with pure butter instead of shortening as I used to do. (I got into the habit of using butter while living in Europe, where vegetable shortening is hard to come by). Yet, my short crust is very flaky and especially has been over the last few years, to the point where people sometimes think it’s puff. (Admittedly, those saying that clearly don’t know real puff if they’re saying that, but it is indicative of a lot of flakiness.) Yet I never buy expensive butter. I always buy the regular domestic butter on sale and stow it away in the freezer in a plastic bag.
In my current home, I have one of those old fridges where the freezer manages to suck all the moisture out of everything (disappearing ice cube phenomenon), and one day, as I was thinking about just how crumbly one of my newly thawed blocks of butter was, it dawned on me: could the freezer be the solution to creating “dry butter”? I know from experience that even things in my freezer that I consider to be sealed manage to dry out at least somewhat, so I would not be at all surprised if the plastic bags I put the butter into before freezing are letting moisture escape from the butter.
What do you think? If I’m right about this, I might have resign myself to a lifetime of thirsty freezers just to ensure an unending supply of flaky short crush 🙂
Jen
Hey Jen!
That’s very interesting indeed. I suppose it depends on how long you’re freezing your butter and how well it’s covered, since air exposure accelerates so-called “freezer burn” or the migration of water out of the food. It’s very possible, though I’d think that the butter would have lost flavor and/or picked up off flavors in the freezer by then. But who really knows? Thanks for an interesting question!
Cheers,
– Joe
Yes! I did a whole side by side comparison of this last year when I lucked into some leaf lard. The lard and the shortening made pretty good crust, but I just couldn’t resist the flavor of the butter.
http://www.fchem101.com/2014/08/pie-crust-battle-of-the-fats/
Hey Janelle!
A perfectly reasonable conclusion! Which reminds me that I need to find some more leaf lard. I’m out!
Cheers,
– Joe
There is a fancy cheese & wine place here & they often have European butter in packages, mostly Irish but I have seen French. One thing I have noticed about it is that a a 1/2 kilo looks a bit smaller than a pound of Land-O-Lakes. Could it be because it is less moist? I supposed it was because they beat more air in but I have not bought a block to compare.
Hey Frankly!
That’s a very interesting question. My sense is that it would be larger since fat is a little lighter than water. Air is another thought, though I’m not aware of any beating that goes on in the butter making process. Hmm…something else to investigate!
Cheers,
– Joe
Just throwing it out there, but I would think you could use unsalted butter as long as you clarified it: basically simmer it until the water evaporates. This is how ghee is made. As a side-effect, the proteins separate and then you end up with a cooking oil with a very high smoke-point suitable for high-heat cooking.
Joe,
In your now abundant free time, take a look at “The Trans Fat Solution” by Kim Severson of the NY Times. Made a believer out of me and didn’t take too long to read.
Enjoy your summer.