A.Tilesetter and author Michael Byrne responds: No grout I ever used or heard of contained a built-in sealer, and although latex and epoxy grouts are somewhat more stain resistant than regular Portland cement grouts, a quality high-performance sealer should always be applied — after the grout has cured — to help reduce staining and to make housekeeping easier.
White grout is never the best choice for any tile installation intended for a heavy-use or food service area, and without a sealer, it may turn "antique" white or even gray. Bleach can sometimes be used to remove stains from white grout, but it will fade colored grout. Once grout has been cleaned, it should be allowed to dry thoroughly...
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