Can instant milk be substituted for regular milk in recipes?
First, some background information: Milk is turned into powder either through vacuum evaporation or freeze-drying. Instant milk made from whole milk turns rancid quickly, so nonfat versions (shelf-stable for up to 12 months) are much more common.
In the test kitchen, we reconstituted Carnation Instant Nonfat Dry Milk with water and used it in béchamel, crème anglaise, and yellow cake, comparing these to versions using regular whole milk. Somewhat to our surprise, the instant milk proved a reasonable contender. In béchamel, while most tasters favored the whole-milk batch, some endorsed the instant-milk sauce for its “lighter consistency” and “buttery flavor.” The crème anglaise was another close call, with more than half of tasters choosing the instant-milk version for its “bright taste.” Instant milk had somewhat less success in the yellow cake test. Though acceptable, tasters felt the instant-milk cake had a tougher crust and a slightly drier texture than the whole-milk version.
Our conclusion: If you’re not one to stock milk in your refrigerator and you can live with small but acceptable compromises in recipes, it makes sense to keep instant milk on hand.