Total protein content in samples of dry red wine from various manufacturers for quality and authenticity control

Wine quality control is performed, which is based on spectrophotometric determination of total protein content with use of Coomassie G-250 dye, combined with analysis of optical absorbance spectra of wine samples. This approach is characterized by simplicity of procedure, rapidity and high availability of reagents and equipment, and all this makes it applicable for quality control of wine by practically any laboratory, and for visual qualitative analysis in field and home conditions. 10 samples of dry red grape wine are analyzed, and total protein content varies by no more than 35% from the average value among all samples, which is 248 μg/mL. Visual estimation of protein content also yielded results close to the exact ones measured; thus, the method is prospective to be applied for field and home conditions.