Measuring electrochemical fruit quality of refrigerated `Hanita' plum by Bioelectric Vincent method

Abstract

`Hanita' plums were stored at 0, 5 and 12 degrees C for up to 15 days plus 1 day at 25 degrees C to investigate the temperature effects on the electrochemical parameters measured by Bioelectric Vincent method, and on physical and physiochemical attributes as well. Weight and firmness loss was the lowest in plums refrigerated at 0 degrees C during the storage period. Plums stored at 0 and 5 degrees C retained vitamin C content in the course of storage while those stored at 12 degrees C did not. Marked changes in fruit skin and flesh colour were recorded regardless of the temperatures but the changes were the lowest in plums stored at 0 degrees C. Significant changes in electrochemical parameters were also noted for plums regardless of the storage temperatures. At the end of their storage period, plums had lower redox potential values, higher pH values and lower resistivity values irrespective of the temperatures. P-value, on the other hand, increased markedly for plums at 0 degrees C, less markedly for plums at 5 degrees C and slightly decreased for plums at 12 degrees C at the end of storage period. Plums refrigerated at 0 degrees C performed very well by resisting weight, firmness, soluble solids and vitamin C loss, and changes in colour parameters. However, plums at 0 degrees C exhibited the highest P-value indicating the lowest vital activity according to Bioelectric Vincent method.