I've been teaching a series on cleaning science these past 4 newsletters. Last week, I gave some examples of how to think through the cleaning of soap scum and glass etching in showers. This week, we're going to share my biggest secrets... "Ken, how do you get the kitchen sink so clean?"
Tarnish on Stainless Steel – This is formed through chemistry (oxidation and mineral ions in hard water). The tarnish layer is acidic and requires only A & C to clean. You need a product like Bar Keeper’s Friend™, which has an acidic pH of 1.5 to 2.5. It eats the tarnish instantly, thus temperature and time are not relevant. With the soft part of a sponge or cloth, you can use light agitation to remove the tarnish. For stubbornly tarnished sinks, use more product and more agitation like a scrub pad or light steel wool.
Discoloration on White Ceramic or Stone-Based Sinks – These surfaces are very porous and react with food and the metal in wet silverware. The reaction that occurs discolors the white to a yellow, blue, or orange (rust) color. The most effective solution requires C & T. Use a heavy alkaline like ammonia or bleach with a pH of 11-13. Allow the chemistry to work with a 2-5 minute dwell time (from experience). The stronger the alkaline, the less time is needed.