The traditional process of reducing the foam in maple syrup has included the use of lard. Previously, local producers would hang pork fat over a tub of maple syrup and let drops of fat drip into the syrup. Others used milk, cream or butter. If animal products are used in the form of lard or milk, the amount is minute. For example, eight to ten gallons of syrup will involve a quarter of a teaspoon of cream or a pea-sized drop of butter.
Vegetable oil is a common defoaming agent.
It can be applied to the end of a wooden stick and dipped into the foaming part of the maple syrup. Most manufacturers of maple syrup now use vegetable oil or synthetic defoamers instead of lard. Corn syrup is the main ingredient of most pancake syrups. Most syrups do not use lard, with the exception of certain small-scale products. Brands which are kosher certified, such as Spring Tree or Maple Groves, are unlikely to contain animal products in their defoamers.