Biospeckle activity measurement of Indian fruits using the methods of cross-correlation and inertia moments

This paper presents biospeckle activity evaluation using two methods namely spatial-temporal speckle correlation and inertia moment applied for three different Indian fruits namely apple, pear and tomato for the first time. The bioactivity was determined by means of the cross-correlation functions of the intensity fluctuations and using inertia moment of the THSP image of biospeckles. Significant changes in bioactivity were observed during their shelf lives. From the study, it is found that the activity is higher for pear in comparison to the apple and tomato as predicted by IM method. Biospeckle activity decreases with aging of the fruits but the decrease is more in pear & relatively less in the case of apple and tomato as predicted by cross correlation technique. Further it is also concluded that the activity changes according to their respiration rates. By the comparative study between the two methods it is found that IM is more reliable to predict the bioactivity levels in fruits in comparison to the cross-correlation technique as IM measures the bioactivity directly. (C) 2012 Elsevier GmbH. All rights reserved.