Urnex Biocaf Milk Frother Cleaning Liquid Urnex Biocaf Milk Frother Cleaning Liquid is formulated to break down build-up left behind from milk proteins and fat in your espresso machine milk delivery system. Also cycles through automatic milk frothers for easy cleanup and cleans traditional steam wands and milk frothers. Urnex Full Circle Espresso Machine Milk Cleaning Liquid is biodegradable, phosphate free, and odorless. It is recommended to use Full Circle Milk Cleaning Liquid after each machine use. Contains a single 1L Bottle for approximately 33 uses. Use 30ml of cleaning liquid per 500ml of water.