Journal of Food Physics, 1998-1999
Original papers - P. László, E. Vozáry, J. Zana: Physical properties of the apple varieties during piking and storage
3 PHYSICAL PROPERTIES OF THE APPLE VARIETIES DURING PICKING AND STORAGE P. László, E. Vozáry, J. Zana Szent István University, Department of Physics-Control 1118 Budapest, Hungary, Somlói út 14-16. ABSTRACT Change of quality of 6 apple varieties were tested during the harvesting period apple varieties. Rheological tests were carried out measuring the yield stress, rupture stress, their ratio and the area below the rheogram (the labour of deformation). Alsó colorimetry tests were applied using a reflection spectro-colorimeter. The results were evaluated in the Nemcsics’s COLOROID system. Electrical properties were tested by a Hewlett-Packard instmment in the rangé írom 10 Hz to 20 Hz and the resistance and electric capacity were calculated. The resistance measurement can be applied succesful fór characterization of harvesting period. INTRODUCTION Fór testing the mechanical properties the deforming force at the rupture point was measured using a computerised data acquiring method. The colour of the fruits was tested by getting a continuous colour spectrum in the rangé of 400-700 nm. We made a comparison between the varieties using well known and new colour properties. The bio-electric properties were tested below the epidermis, in the cells of the collenchime and the parenchime. The absolute value of the impedance was the linear function of the frequency at a probability level greater than 95 percent. Journal of Food Physics 1998-1999