THE NATURAL OPTION:
Below are ingredients for a natural solution commonly used to address tough-to-remove kitchen grease:
Combine one part lemon juice and one part vinegar. Add two parts baking soda to the mixture and stir to make a paste. Spread the paste over the grout and tile. Make sure it has good contact with the hardest hit grease areas. A soda glass backsplash may get filmy during this process but won't be harmed by the gentle grease remover. Simply buff out the glass until its former shine returns.
WHAT THE PROS USE:
Tech Grout Cleaner is a little more serious and is sold at most home improvement stores. It's what professionals try for tough jobs. It's nonacidic, odorless and 100 percent biodegradable.