A method of producing a canola protein isolate having a canola protein content of at least 90 wt% (N x 6.25) d.b., which comprises: (a) extracting canola oil seed meal at a temperature of at least 5°C to cause solubilization of canola protein from meal and to form an aqueous protein solution having a protein content of 5 to 40 g/L and a pH of 5 to 6.8, (b) separating the aqueous protein solution from the spent oil seed meal, (ci) increasing the protein concentration of the aqueous protein solution to 50 g/L or less while maintaining the ionic strength substantially constant by using a selective membrane technique to provide a partially concentrated protein solution, (di) adding calcium salt solution to the partially concentrated protein solution to a conductivity of 15 to 25 mS to cause a precipitate to form in the partially concentrated protein solution, and removing the precipitate from the partially concentrated protein solution, (ei) diluting the partially concentrated protein solution with 0.5 to 20 volumes of water having a temperature of 2° to 90°C, or (cii) adding calcium salt solution to the aqueous protein solution to a conductivity of 15 to 25 mS to cause a precipitate to form in the protein solution, (dii) removing the precipitate from the protein solution, (eii) diluting the aqueous protein solution with 0.5 to 10 volumes of water having a temperature of 2° to 90°C, (f) acidifying the resulting solution to a pH of 2.5 to 4.0 to produce an acidified clear protein solution, (g) increasing the concentration of the acidified clear protein solution to 50 to 250 g/L while maintaining the ionic strength substantially constant by using a selective membrane technique to provide a concentrated protein solution, (h) optionally diafiltering the protein solution, and (j) optionally drying the concentrated protein solution to provide a canola protein isolate having a protein content of at least 90 wt% (N x 6.25) d.b.. (a) extracting canola oil seed meal at a temperature of at least 5°C to cause solubilization of canola protein from meal and to form an aqueous protein solution having a protein content of 5 to 40 g/L and a pH of 5 to 6.8, (b) separating the aqueous protein solution from the spent oil seed meal, (ci) increasing the protein concentration of the aqueous protein solution to 50 g/L or less while maintaining the ionic strength substantially constant by using a selective membrane technique to provide a partially concentrated protein solution, (di) adding calcium salt solution to the partially concentrated protein solution to a conductivity of 15 to 25 mS to cause a precipitate to form in the partially concentrated protein solution, and removing the precipitate from the partially concentrated protein solution, (ei) diluting the partially concentrated protein solution with 0.5 to 20 volumes of water having a temperature of 2° to 90°C, or (cii) adding calcium salt solution to the aqueous protein solution to a conductivity of 15 to 25 mS to cause a precipitate to form in the protein solution, (dii) removing the precipitate from the protein solution, (eii) diluting the aqueous protein solution with 0.5 to 10 volumes of water having a temperature of 2° to 90°C, (f) acidifying the resulting solution to a pH of 2.5 to 4.0 to produce an acidified clear protein solution, (g) increasing the concentration of the acidified clear protein solution to 50 to 250 g/L while maintaining the ionic strength substantially constant by using a selective membrane technique to provide a concentrated protein solution, (h) optionally diafiltering the protein solution, and (j) optionally drying the concentrated protein solution to provide a canola protein isolate having a protein content of at least 90 wt% (N x 6.25) d.b..