Reader Ellen writes:
[Milk powder] is the bane of anyone who is substantially lactose intolerant…a lot of breads, cookies, doughnuts, salt & vinegar chips, and even flour tortillas…have unknown amounts of lactose. Joe, any thoughts on non-dairy additions that could provide the same texture improvements? More egg yolks?
I can see where that might be a problem, reader Ellen! The good news, at least for home bakers, is that there is no end of substitutes for milk powder when it comes to tenderizing a bread, cookie or crust. Fat (or oil) is probably the most common tenderizer. But really anything that is finely ground and non-wheat can work to undermine gluten or otherwise make the crumb of a baked good less uniform and stable.
One of my go-to’s in that department is corn starch, which, like milk powder is mostly neutral-tasting and performs a lot of the same jobs. Potato flour or even cooked (riced or mashed) potato, depending on the application, is just as good. Nice thing about the cooked potato is that it also brings moisture to the party. Use it for cookies or doughnuts. I put a lot of it in my Chicago-style pizza crust.
You mentioned egg yolks. Raw yolks work very well, though depending on what you’re making, the extra liquid can make a dough or batter too soft or thin. However cooked yolks, pushed through a very fine sieve, make a stellar secret weapon when it comes to tenderizing. They add some nice color and rich flavor too!
Aside from those faves, the world of non-wheat…anything…is open to you, provided the ingredient you choose can disperse fairly well in a mixture: alternative grain flours, nut flours, rice flours, chickpea flour, coconut flour, cooked (mashed) beans, tapioca/cassava flour, arrowroot, agar, carrageenan, ground coffee, coffee flour (yes, there is such thing), cocoa powder, chocolate, cocoa butter, oils of all kinds, shortening, animal fats…I’m starting to get dizzy. But I think you get the point here, reader Ella. The food manufacturing world may not be entirely creative when it comes to finding milk powder alternatives, but we sure can be. So have at it, and let me know if you have any specific questions!