Enzymatic corn wet milling process: Enzyme optimization & commercial trial

An enzymatic corn wet milling process has been developed that replaces or reduces the use of sulfur dioxide (SO₂) by using proteolytic enzymes. An acid fungal protease (GC106) was evaluated in this process, and its dose was optimized for starch yield using a laboratory enzymatic wet milling procedure. Starch yields from enzymatic wet milling treatments were compared to a conventional control treatment using 2 000 ppm SO₂. To reduce enzyme dose, a treatment with a low level of SO₂ (600 ppm), along with enzyme, was evaluated and compared to the control treatment. Starch yields increased from 58.7% to 70.9%, with an increase in GC106 dose from 0 to 10 mL. Enzymatic wet milling treatment with 1 mL of GC106 and a reduced amount of SO₂ (600 ppm) resulted in a starch yield similar to that of the conventional control.