Fruit quality evaluation using biospeckle techniques

This paper presents a spatial-temporal speckle correlation technique applied for the quality assessment of different Indian fruits namely apple, pear and guava for the first time. The method is noncontact, noninvasive and non-destructive and is based on the study of variations in biospeckles with time. Temporal and spatial changes of subjective speckle patterns of the fruits have been measured. Using the above technique the cross-correlation coefficients of biospeckle patterns have been calculated. The cross-correlation coefficients change subject to the freshness and the storage conditions of the fruits. Significant changes of cross-correlation coefficient values were observed during their shelf lives. We have plotted cross-correlation coefficients for all the fruits on inter day basis. From the study, it is found that the cross-correlation coefficient value difference decreases with the increase of shelf-life storage time. It is also concluded that shelf life of the guava is smaller than that of the apple and pear. Significant exponential changes of the cross-correlation coefficient value difference were also observed during their shelf lives. This show that the method can be utilized for quality evaluation of different Indian fruits namely apple, pear and guava.