Short answer: depends Long answer: The “inside” of particle accelerators is a chamber kept under ultra high vacuum conditions (about equal to the atmosphere on the dark side of the moon), which would already be kind of like ultra air drying a steak using some pretty large turbo pumps. If we ignore that aspect, the next likely “cooking” scenario would be long before the particles are “accelerated.” Inert fuel sources need to be ionized in order to manipulate the particles to do the accelerating. The ionization of those gases come in a lot of forms, and at least one type is essentially high frequency high energy current that creates a sort of microwave effect on the fuel source to separate the electrons from the protons of a fuel source. Should be mildly effective at heating a steak, but the system would likely destroy itself due to trying to run continuously for long enough to cook the steak all the way through. TLDR; steak would either be dried via vacuum or the ionization system would melt down trying to heat the mass of the steak.