If you prefer a high alkaline, solvent fortified chemical to deal with heavy soil on hard surfaces, you want Viper Venom.
The original tile and grout cleaner, it removes years of built-up grease, dirt and stains.
Dilute it 1:1 for tough jobs, more for lighter jobs. You'll see the dirt start to lift out of the grout even before you begin using your machine. Rinse well.