Research On Mechanical Damage Of Different Types And Varieties On Apple And The Effects Of Chitosan On Damage Fruit

In this paper, with the apple fruit as material, the influences of different mechanicaldamage on the storage effect of Red fuji apple was studied, and the response to mechanicalinjury was compared between different apple variety, meanwhile, the effect of chitosan onmechanical damage apple was researched too. The result showed as follows:(1) Mechanical damage had reduced the storage effect of 'Red Fuji' apple, but there weredifferences among the compression, vibration and impact injury. Smaller compression andvibration injury could make a similar result to bigger impact injury. Meanwhile, effect of eachkind of mechanical damage was enhanced with the increase of strength. Therefore, theprediction of storage ability for damage apple should considerate the two aspect with thetypes and intensity of the injury.(2)'Red Fuji' apple damaged easily than 'Qinguan'. As time passed, the woundbrowning volume was expansion, more serious towards tangent and less serious towardsvertical tangent direction.'Red Fuji' apple expanded more than 'Qinguan'. After damaged,storage quality had reduced of both apple varieties,'Red Fuji' apple reduced by a smallermargin than 'Qinguan' of fruit firmness, titrable acidity and weight loss. The changes ofsoluble solid had no differences between each other.(3) The resistance response to damage by60cm height drop of 'Red Fuji' and 'Qinguan'apple was different. After injured, their PPO, POD, PAL activity increased. The enzymeactivity peak of 'Red Fuji' apple was headed, and with a lower activity in later period. Theenzyme activity peak of 'Qinguan' obviously increased but not headed, and with a higheractivity in later period. The Total phenol content was decreased, and 'Red Fuji' appledecreased more.(4) Chitosan reduced the expansion trend of wound browning volume in 'Red Fuji' apple,weakened the bad influence in initial stage, and slowed down the decrease of storage quality.It reduced the respiratory peak value and weight loss, increased firmness, soluble solid andtitrable acidity. It lowered the enzyme activity peak in aging process, increased the resistancein later period and storability.