Detergent composition and methods of preventing aluminum discoloration

A method of warewashing comprising:

• obtaining a solid, alkaline, non-staining detergent composition comprising:
• from about 60 wt-% to about 70 wt-% of a sodium carbonate alkalinity source;
• from 12 wt-% to about 15 wt-% (by actives) of an alkali metal silicate;
• from 5 wt-% to about 10 wt-% (by actives) of an ethylenediaminetetraacetic acid (EDTA) or salts thereof;
• from about 1 wt-% to about 10 wt-% (by actives) of a methylglycine-N,N-diacetic acid (MGDA) or salts thereof;
• from 2.5 wt-% to about 5 wt-% (by actives) of at least one water conditioning polymer comprising polymaleic acid homopolymer, a polyacrylic acid homopolymer, or combinations thereof;
• and
• from about 1 wt-% to about 5 wt-% of an alcohol alkoxylate nonionic surfactant defoaming agent;
• wherein a weight ratio by actives of ethylenediaminetetraacetic acid or salt thereof to methylglycine-N,N-diacetic acid (MGDA) or salt thereof is at least about 1:1;
• wherein the composition is substantially free of nitrilotriacetic acid (NTA) diluting the detergent composition to provide a use solution with a concentration of at least about 1500 ppm detergent;
• contacting a ware with the use solution;
• and
• removing soils from the ware without causing discoloration thereof.