I use knives made from rasps in the kitchen all the time. I just clean them with a brush and warm soapy water. The same as other utensils and cutting boards that can harbor bacteria if not cleaned properly. In fact, I feel that it takes much less effort to clean such a knife thoroughly, than a cutting board for instance. Cutting boards have a multitude of fine to large cuts in the surface that can catch and hold food debris and bacteria much more readily than the remaining rasp pattern on the knifes I make. And cutting boards made of wood are somewhat permeable as well. But you don’t hear people freaking out about using a less than pristine cutting board.
Frankly, I dont know how the idea about cutlery with a brut de forge finish, blacksmith finish, rasp texture, peined texture, or anything else considered a “lack of finish” as being not food safe, got so much traction. Just clean it. It doesn’t need to go into an autoclave, just a good scrub is all that is required.