Using brix refractometry to measure the total protein level in chicken egg whites: Preliminary data

Abstract

This study was conducted to investigate the feasibility of using Brix refractometry as a rapid method to measure the total protein level in chicken egg white samples. A total of 39 chicken eggs were purchased from local grocery stores and analyzed using three techniques: UV–Vis spectrophotometry, Brix refractometry, and the Bradford protein assay. Data shows that there is a strong positive correlation between the total protein levels as determined by UV–Vis absorbance values and the Brix values. No correlation (positive or negative) was found between the total protein levels as determined by the Bradford assay and either the Brix refractometry or the UV–Vis spectrophotometry. In comparison to UV–Vis spectrophotometry and the Bradford assay, Brix refractometry is both rapid and simple. It requires no sample processing steps, no special personnel training and can be conducted in any facility. We conclude that Brix refractometry is a suitable technique for rapid assessment of total protein level in chicken egg whites, although additional large-scale studies should be conducted to further validate the method.