Sprouting Inhibition Mechanism And Processing Quality Of Potato Tubers Influenced By Exogenous Ethylene

Ethylene had been used as a potato sprout suppressant with better storage effect in many countries,with no toxicity residual compared with other chemical sprout suppressants.However,its mechanism of sprout inhibition was unclear,and the influence on further potato processing attributes have not been defined.In the present study,solid exogenous ethylene releaser was used to inhibit the sprouting of potatoes,the variation of carbohydrate metabolism and involved enzymes were determined to reveal the machanism for the inhibiting effect of ethylene.In addition,effect of exogenous ethylene on processing attributes of patato products,such as fresh-cut and deep-fried potatoes,were studied.Research results were showed as follows:1.Exogenous ethylene could restrain the potato sprout effectively and reduced germination index,however,little effect on its initial germination time was observed.The germination indexs in the Ethylene treatment group(Eth)and control(CK)were 69.2% and 43.1%,respectively,which was significant difference between them(P<0.05).The order of germination index was ranked CK > 91.7?L/L > 193.3?L/L,the germination index was reduced by 12% and 23% respectively.2.Exogenous ethylene affected glycometabolism and the activity of related enzymes significantly during sprouting.For specific performance,exogenous ethylene can improve activity of acid invertase,sucrose synthase,sucrose phosphate synthase and amylase,improve the content of total sugar and reducing sugar,accelerate the degradation of sucrose and starch,reduce the content of sugar and starch;Exogenous ethylene were not significantly affected the activity of neutral invertase and starch phosphate synthetase.3.After the treatment of ethylene and 1-methylcyclopropene(1-MCP),the accumulation of total phenol in potato tubers were reduced,and the increasing trend of chlorogenic acid was delayed.To some extent,ethylene and 1-MCP affected the potato enzymatic browning reaction.Exogenous ethylene can improve the respiratory intensity of fresh-cut potato,increase the browning degree,improve the activity of polyphenol oxidase(PPO)and peroxidase(POD),promote the browning of fresh-cut potato.1-MCP can reduce the activity of PPO and POD,and inhibit the potato browning.ethylene and 1-MCP can suppress the phenylalanine ammonia enzyme(PAL)activity.For color parameters,there were a negative correlation between L* and b* with browning degree,PAL activity,and POD activity.4.To some extent,exogenous ethylene and 1-MCP affected the sensory quality of the fried potato chips,the exogenous ethylene lowered the sensory quality of potato chips,in the contrary,1-MCP improved the quality of potato chips.Exogenous ethylene and 1-MCP improved the moisture content and oil content in fried potato chips.Meanwhile,exogenous ethylene increased the content of acrylamide,and 1-MCP reduced it.