Study On Compression Properties And The Vibartion Effect On Postharvest Physiology Quality Of Cucumis Melo Hetao

Quasi-static compression and vibration of Hetao Muskmelons study were conducted, in order to provide theoretical basis for deep-processing, postharvest handling and improvement of storage and transportation conditions. The following conclusions were draw from the experimental results:(1) The mechanical parameters were all significantly affected by the factors,such as indenter, size and compression parts. Bio-yield point exist in flat indenter, but no in cylindrical indenter. Big fruits were break difficultly. The fruit compressed in vertical direction were more easily get to the yield state than that of compression in horizontal direction.(2) Compression curves were affected by firmrness of fruits and loading rate. Force-deformation curve of the initial phase was a clear linear relationship if compression rate of hard fruit was at 5 ~ 15mm/min interval.(3) The firmrness of Hetao Muskmelons may be nondestructively measured by the equation of force/deformation. The regression equation were established between storage time and mechanical properties parameters.(4) Vibartion stress enhanced respiration intensity and increased the organization cell membrane penetration,the influence changed with different vibration way, different vibration time and different vibration frequency: fruit of vibratd in vertical way>horizontal way; fruit of vibrated for 40min>30min>20min; fruit of vibrated by 15Hz>10Hz>5Hz. Vibration stress increased respiration peak or earlied respiration peak time , speeded up the loss of cell membrane integrity process, advanced Vibration stress accelerates senescence of Hetao Muskmelons.(5) Vibartion stress reduced firmrness of Hetao Muskmelons,which debased the stroage quality.Vibartion stress added TSS content and accelerated the degradation of nutrients.The longer time of vertical vibration and the fiercer frequency are, the more obvious of these effects are.(6) There were a certain relevance among respiration intensity, cell membrane penetration, firmrness and TSS. Statistic analysis indicated that firmrness presented a significant largest negative correlation with cell membrane penetration, and a least correlation with respiration intensity.