I used to powderize the food, but it gets eaten just fine whole. I heard of many who wet the food but i don't check on them for several days sometimes and worry about mold. I mostly try to check often enough to not run out of water crystals usually every 2-3 days. I use a variety of cat, dog and fish foods. I add fruits and veggies 2-3 times a week.
I grind mine in a coffee bean grinder and check daily. I feed a lot of fruits and veggies. I have also found that my B.dubia LOVE fish flake food, which I had heard from roach breeders was not usually the case.