Like all the other maintenance programs, milk system cleaning frequency depends on how often the coffee machine is used. Milk is a food product and has an especially short expiration date. Due to this reason, we recommend that the parts that are used for making beverages with milk be cleaned as often as possible. If milk frother is rinsed every evening with warm water or is left to soak overnight then cleaning with an antibacterial liquid once a week is enough. If the daily maintenance was skipped for at least a couple of days, due to hygiene reasons perform the disinfection immediately, before making another cup of coffee.