Effect of 1-MCP,ClO_2and Na HSO_3 on lipid oxidation and antioxidant activities of green walnut kernel

The effect of 1- MCP(1 mg / L) + ClO_2(50 mg /L) 、1- MCP( 1 mg /L) + Na HSO_3( 50 mg /L) and 1- MCP( 1 mg /L) with PE films( 40 μm) was examined on the lipid oxidation and antioxidant activities of green walnut kernel during storage at 4 ℃,RH 70% ~80%.Acid value,peroxide value,Lipoxygenase( LOX) activities,reducing power,DPPH free radical scavenging activity,superoxide anion( O_2~-·) scavenging activity and total phenols content of the kernel were measured at regular intervals. Results showed that acid value and peroxide value reduced with1- MCP,Cl O_2 and Na HSO_3,especially 1-MCP + NaHSO_3( p < 0.05),and they were 0.518 mg /g and 0.125 meq /kg respectively at 30 d,but CK were 1.103 mg / g and 0.214 meq / kg. LOX activities followed the increasing order:1- MCP + ClO_2< 1- MCP + Na HSO_3< 1- MCP < CK at 30 d. Reducing power,DPPH· scavenging activity,O_2~-·scavenging activity and total phenols content increased more with 1- MCP + ClO_2 than CK,and maximum were0.571,52.78%,31.46% and 4.28 mg / g respectively.