| A significant amount of information is available on the mechanical properties of fruits. Both elastic and viscoelastic properties of fruits have been the subjects of intensive research in the post two decades. The most studies generally focused on characterizing some basic mechanical properties without considering the nonhomogeneous and anisotropic properties of fruit. Little detailed information is available on the nonhmogeneus and anisotropic mechanical properties of fruits.There are numerous situations during havesting, handling, transportation, and processing operations in which fruits are subjected to dynamic loading. Accurate prediction of dynamic responses of fruit under these loading conditions requires better understanding of their dynamic properties. Conventional quasi-static creep and stress relaxation loses are not adequate for obtaining dynamic viscoelastic property data due to compuicating dynamic effect. Little information is reported on the dynamic properties. Therefore, dynamic tests are often required or preferable for characterizing the properties of fruits.The objectives of this article are to: (I) Describe distributed difference of anisotropic firmness and sugar content of peach and pear, to provide a valuating quality method. (2) Obtain anisotropic mechanical properties and stress relaxation properties of pear. (3) Report the dynamic complex modulus and phase angle of peach and pear measured using the proposed method.The study was conducted on distributed difference of anisotropic firmness and sugar content of Huanghua pear, Luyung pear, Cangfangzaosheng peach, Daguanshan peach, to determine the effects of ripeness, latitude and longitude. The firmness and sugar content of pear and peach are signficantly influenced by latitude (top, middle and bottom) and ripeness (least, intermediate and most). The two indexes of the pears are either quite small or not significant by longitude-measured points. The distribution of the furriness and sugar content in the pear and peach were analysed, and the relationship between firmness and sugar content were established, and generation mechanism of distributed difference was discussed. The better positions are used to evaluated pear and peach quality were proposed.The study was to determine the effects of ripeness and of specimen orientation and location within fruit on failure stress, strain, and energy, and apparent modulus of elasticity (Young抯 modulus). Compression test were on Dangshan pear. The four mechanical properties significantly influenced by specimen orientation (radial, tangential, vertical), latitude location from stem to calyx (Top, middle, bottom), and depth (from skin to core, inner and outer) and, to a smaller extent, by the orientationX latitude, orientationXdepth, and latitudeX depth. The longitude and its interactions are not sigificant. The distributed equations of the four propertieswere developed. The generation mechanism on distributed difference of mechanical properties was discussed.The stress relaxation work was carried out using various specimens of orientation, location with pear. The decay modulus, the equilibrium modulus, time of relaxation and specific viscosity in the relaxation model are significantly influenced by specimen orientation, latitude, depth and deformation. The longitude of specimen is not significant.The article describes a dynamic method for measuring the complex modulus and phase angle of Huanghua pear, Luyung pear, Cangfangzaosheng peach, Daguanshan peach over a range of frequencies. Experiments were conducted to measure the complex modulus and phase angle, and their relationship with initial stress, vibration input and ripeness of fruit. The magnitudes of the complex modulus and phase angle increased as the frequency increased, from 0 to 200Hz. As expected, initial stress had a significant effect on the magnitude of the complex modulus, but not on the phase angle. Vibration amplitude (power) had little effect on the modulus and phase angle. Especially, the complex modulus a...
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