Abstract: This experiment was designed to study the effect of preventing milled and filtered potato liquid from browning by sour liquor which was fermented naturally from pea. Results showed that sour liquor possesses the action of preventing milled and filtered potato liquid from browning, and the factor of brown-preventing in sour liquor is not its major metabolic acid, but is its microodanism and some thermolabile substance in the supernatant liquid which can efficiently inhibit the activity of polyphenoloxidase (PPO) from potato.

Key words: Sour liquor from pea Milled and filtered potato liquid Browning density (BD) Polyphenoloxidase (PPO)