Is ammonium hydroxide safe to be used for sanitizing food?
In pure form, aqueous solutions of ammonia ($\ce{NH3}$) cannot be consumed. Solutions containing 5 % ammonia or more are considered “corrosive” (causing severe skin burns and eye damage).

However, in reasonable quantities or in dilute form, aqueous solutions of ammonia can be generally used safely in food. They are sometimes named “ammonium hydroxide”, “ammonia aqueous”, or “aqua ammonia”. The food additive code (the E number, which is commonly found on food labels) of aqueous solutions of ammonia is E 527.

This food additive is approved in the European Union as well as in the United States.

For example, aqueous solutions of ammonia are used in food processing as pH control agent (acidity regulator), leavening agent, surface-finishing agent, or additive to boiling water.