A composition is described that includes: (a) at least one alkali metal hydrogen sulfate anhydrous, such as sodium hydrogen sulfate anhydrous (b) at least one salt, that is different than the alkali metal hydrogen sulfate anhydrous, which is selected from alkali metal salt and/or alkaline earth metal salt, such as sodium chloride and/or magnesium sulfate and (c) optionally a colorant, in which the composition is in the form of a tablet. There is also described a method of forming a treated aqueous stream using the tablet composition. There is further described a method of forming a treated sanitizing aqueous stream that involves combining the treated aqueous stream with a feed sanitizing aqueous stream. In addition, there is described a method of sanitizing a surface that involves applying the treated sanitizing aqueous stream to a surface to be treated, such as animal carcass surfaces.
