Prevention of Browning in Mushroom by Onion Extract

The inhibitory effect of onion extract on mushroon tyrosinase activity was investigated. The enzyme activity was inhibited by 96.3% with th addition of onion extract. The inhibitor action of onion extract toward mushroom tyrosinase activity slightly increased after heat treatment at 10$0^{\circ}C$ for 10 mn (97.5%) and decreased after incubation of the extract at pH 2.3 for 3hrs (79.9%). However, the inhibitor action of the extract after dialysis decreased to18.8%. The onion extract showed drastic inhibition of the browning in mushroom.