The measurement of traditional laser biospeckle is significantly affected by experimental parameters. To address this problem, dynamic light scattering and fluorescence correlation spectroscopy were used to characterize the biospeckle activity. An experimental setup was built and tested with traditional Chinese medicine syrup, yogurt, old yogurt, tomatoes, and apples. The results show that the constructed metric based on the correlation coefficient with a clear physical meaning is mainly determined by the speed of particle movement in the sample, which has an average error less than 5%. As the metric is almost independent of the exposure time of camera and region of interest, it is beneficial for the biospeckle technology to be used in practical applications. Since various characteristics of biological samples in the agricultural and pharmaceutical fields are related to the speed of particle movement, this method is expected to provide a new non-destructive testing tool for food and pharmaceutical industries.