In addition to the requirement that all ingredients (including anti-foam and other production aids) used to make a kosher product must be certified kosher, the equipment used to produce the product must meet kosher requirements as well. As previously discussed, meat and dairy products cannot be mixed or produced on the same equipment. In addition, if a product will be pareve (neutral), it cannot be produced on dairy or meat equipment.
In order to make used equipment suitable for kosher production, or to change a production line from meat or dairy to pareve, a special process, called kosherizing, must take place. Kosherizing is done by the rabbi assigned to your facility and involves a process of cleaning and purging the equipment of its non-kosher status. After all equipment is left idle for 24 hours, it is meticulously cleaned by facility staff and inspected for cleanliness by the rabbi. Then, depending on the type of equipment, the rabbi oversees the actual kosherization. There are a few methods, which vary based on the equipment, and include boiling, use of steam, and purging through direct contact with fire.
Once this process is complete, the production equipment becomes kosher according to Jewish law. Kosherization is also required to produce Passover products in a facility that was used to produce other products during the year.