We are supplier of Cold Brew Coffee Dripper Cold brew or cold press refers to the process of steeping coffee grounds in room temperature or cold water for an extended period. The cold-press process requires coarse-ground beans are soaked in water for a prolonged period of time (5 hours). The water is normally kept at room temperature, but chilled water can also be used. The grounds must be filtered out of the water after they have been steeped using a paper coffee filter, a fine stainless steel sieve. The result is a coffee concentrate that is often diluted with water or milk, and can be served hot, over ice, or blended with ice and other ingredients such as chocolate.