Production of soluble protein products from pulses

A method of producing a pulse protein product having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis, which comprises:

• (a) mixing a pulse protein source with water and separating the resulting slurry into a water-soluble fraction and fractions of coarse, water insoluble solids and fine, water-insoluble solids,
• (b) concentrating the water-soluble fraction from step (a) while maintaining the ionic strength substantially constant by membrane filtration to provide a concentrated soluble fraction having about 25 to about 75% of the volume of the initial water-soluble fraction,
• (d) combining the concentrated soluble fraction with the water-insoluble solids fractions from step (a) to provide a mixture,
• (e) adding a calcium salt to the mixture to provide a calcium salt concentration of less than about 1.0 M and to provide an aqueous solution of pulse protein and residual solids material,
• (fi) separating the aqueous solution of pulse protein from the residual solids material,
• (gi) optionally diluting the aqueous solution of pulse protein, and
• (hi) adjusting the pH of the aqueous solution of pulse protein to a pH of about 1.5 to about 4.4 to produce an acidified aqueous pulse protein solution, or
• (fii) optionally diluting the aqueous pulse protein solution and residual solids material,
• (gii) adjusting the pH of the aqueous pulse protein solution and residual solids material to a pH of about 1.5 to about 4.4 to produce an acidified pulse protein solution, and
• (hii) separating the acidified aqueous pulse protein solution from residual solids material,
• (i) optionally clarifying the acidified pulse protein solution if it is not already clear,
• (j) optionally concentrating the acidified aqueous pulse protein solution while maintaining the ionic strength substantially constant by a selective membrane technique,
• (k) optionally diafiltering the optionally concentrated pulse protein solution, and
• (l) optionally drying the optionally concentrated and optionally diafiltered pulse protein solution.