I have a book with several bread recipes that call for 1-2 tablespoons of powdered milk. This isn't something I usually use and I was thinking substituting it with normal milk, and putting less water to compensate for the added liquid. Would this be ok? And if yes, how much milk should I put for one tablespoon of powdered milk?
A general reconstitution of milk with dried powder is 1/4 dry milk and 1 cup water to reconstitute milk. So 2 tablespoons is 1/8 cup to 1/2 cup of water.
If you want to replace 2 tablespoons, replace 1/2 cup water with milk. 1 Tablespoon is 1/4 cup milk instead of water.
I have done this as a replacement for dried milk in bread many times with success.
Yes, you can. I use the King Arthur Flour Small Pain de Mie recipe all the time http://www.kingarthurflour.com/recipes/a-smaller-pain-de-mie-recipe, which calls for non-fat powdered milk. An answer to another question here Why is milk powder used in bread machine recipes? says to scald the milk, a concept reiterated by the folks at King Arthur. So as an experiment, I made two loaves of bread, identical in every way except that in one I substituted 170 ml scalded skim milk for the powdered milk and that volume of water.
Right out of the oven and three days later, I can find no difference between the two loaves of bread.
My package of powdered milk calls for 7 ounces of water to 1/3 cup powder to make 1 cup of milk, so I figured 8 tsp powder + 7 Tbs water = 1/2 cup milk. I converted to metric just to make the math easier, but it doesn't seem to me to require that much precision.