A number of methods to isolate and quantify protein in Pinot noir wines were evaluated. The combination of precipitation by acetone containing 10% w/v trichloroacetic acid followed by quantification with the Bradford assay, reported in yeast invertase equivalents yielded the most accurate results when compared to micro-Kjeldahl analysis. The technique was validated by dialysis and proteolysis experiments and was used to assay protein in 57 Pinot noir wines. These wines were found to contain protein concentrations ranging from 49 to 102 mg/L. The mannan and tannin content of the wines was also measured, but no correlation between protein content and concentrations of these components was found. The presence of protein in red wines greater than 30 years old at concentrations typically found in white wines contradicts the notion that interactions with tannin severely reduce protein levels. / Graduation date: 2011