What Is a Laundry Enzyme Presoak? - The Spruce
Laundry Enzyme Presoak . Laundry enzyme presoaks are a pre-washing stain removal treatment used to break down protein stains like grass, blood, and baby formula so they can be more efficiently removed during the regular wash cycle. A presoak is necessary when clothes are heavily soiled or stained with oil, protein or tannin stains.