Preparation of acid soluble pulse protein hydrolyzates with little or no astringency and pulse protein hydrolyzates of improved amino acid score

A method of processing a pulse protein material, which comprises:

• a) rehydrating dry powder pulse protein product, having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis (d.b.) and a natural pH in aqueous solution of about 1.5 to about 4.0, to provide a pulse protein solution,
• bi) adjusting the pulse protein solution in pH within the range of about 6.0 to about 8.0,
• ci) treating the pH adjusted pulse protein solution with a proteolytic enzyme to effect hydrolysis of the pulse protein, and
• di1) the hydrolyzed pulse protein material is heat treated to inactivate the enzyme, and
• ei1) the pH of the heat treated hydrolyzed pulse protein material is adjusted to an acid pH value, or, alternatively to di1) and ei1):
• di2) the pH of the hydrolyzed pulse protein material is adjusted to an acid pH value, and
• ei2) the acidified hydrolyzed pulse protein material is heat treated to inactivate the enzyme,
• fi) separating the hydrolyzed pulse protein material by centrifugation to form a soluble fraction and residual solids,
• gi) concentrating and optionally diafiltering the soluble fraction to decrease the content of salt and/or other impurities in the soluble fraction and provide a first pulse protein hydrolyzate (retentate), having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis, which is substantially completely soluble throughout the pH range of about 2 to about 7 and which provides a lower astringency than the pulse protein material YP35-K28-16A YP701 when an acidic beverage containing the first pulse protein hydrolyzate is consumed,
• hi) drying the concentrated and optionally diafiltered first pulse protein hydrolyzate (retentate),
• ii) washing the residual solids to provide a second pulse protein hydrolyzate having a protein content of at least about 60 wt % (N×6.25) d.b. and an improved Amino Acid Score, which is improved compared to the pulse protein material, wherein the washing is effected by mixing the residual solids with water and collecting the washed residual solids by centrifugation, and
• ji) drying the washed residual solids, or
• bii) adjusting the pulse protein solution in pH within the range of about 6.0 to about 8.0,
• cii) treating the pH adjusted pulse protein solution with a proteolytic enzyme to effect hydrolysis of the pulse protein,
• dii) the hydrolyzed pulse protein material is heat treated to inactivate the enzyme,
• eii) separating the hydrolyzed pulse protein material by centrifugation to form a soluble fraction and residual solids,
• fii) concentrating and optionally diafiltering the soluble fraction to decrease the content of salt and/or other impurities in the soluble fraction and provide a first pulse protein hydrolyzate (retentate), having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis, which is substantially completely soluble throughout the pH range of about 2 to about 7 and which provides a lower astringency than the pulse protein material YP35-K28-16A YP701 when an acidic beverage containing the first pulse protein hydrolyzate is consumed,
• gii) drying the concentrated and optionally diafiltered first pulse protein hydrolyzate (retentate),
• hii) washing the residual solids to provide a second pulse protein hydrolyzate having a protein content of at least about 60 wt % (N×6.25) d.b. and an improved Amino Acid Score, which is improved compared to the pulse protein material, wherein the washing is effected by mixing the residual solids with water and collecting the washed residual solids by centrifugation, and
• iii) drying the washed residual solids, or
• biii) optionally adjusting the pulse protein solution in pH within the range of about 1.5 to about 4.0,
• ciii) treating the optionally pH adjusted pulse protein solution with a proteolytic enzyme to effect hydrolysis of the pulse protein,
• diii) the hydrolyzed pulse protein material is heat treated to inactivate the enzyme,
• eiii) separating the hydrolyzed pulse protein material by centrifugation to form a soluble fraction and residual solids,
• fiii) concentrating and optionally diafiltering the soluble fraction to decrease the content of salt and/or other impurities in the soluble fraction and provide a first pulse protein hydrolyzate (retentate), having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis, which is substantially completely soluble throughout the pH range of about 2 to about 7 and which provides a lower astringency than the pulse protein material YP35-K28-16A YP701 when an acidic beverage containing the first pulse protein hydrolyzate is consumed,
• giii) drying the concentrated and optionally diafiltered first pulse protein hydrolyzate (retentate),
• hiii) washing the residual solids to provide a second pulse protein hydrolyzate having a protein content of at least about 60 wt % (N×6.25) d.b. and an improved Amino Acid Score, which is improved compared to the pulse protein material, wherein the washing is effected by mixing the residual solids with water and collecting the washed residual solids by centrifugation, and
• iiii) drying the washed residual solids.

A method of processing a pulse protein material, which comprises:

• a) extracting a pulse protein source with water to form an aqueous pulse protein solution,
• b) at least partially separating the aqueous pulse protein solution from residual pulse protein source,
• c) adjusting the pH of the aqueous pulse protein solution to a pH of about 1.5 to about 3.4 to solubilize the bulk of the protein and form an acidified pulse protein solution,
• d) separating the acidified pulse protein solution from the acid insoluble solid material,
• e) optionally concentrating, diafiltering and diluting the acidified pulse protein solution,
• fi) adjusting the optionally concentrated, diafiltered and diluted pulse protein solution in pH within the range of about 6.0 to about 8.0,
• gi) treating the pH adjusted pulse protein solution with a proteolytic enzyme to effect hydrolysis of the pulse protein, and
• hi1) the hydrolyzed pulse protein material is heat treated to inactivate the enzyme, and
• ii1) the pH of the heat treated hydrolyzed pulse protein material is adjusted to an acid pH value, or, alternatively to hi1) and ii1):
• hi2) the pH of the hydrolyzed pulse protein material is adjusted to an acid pH value, and
• ii2) the acidified hydrolyzed pulse protein material is heat treated to inactivate the enzyme,
• ji) separating the hydrolyzed pulse protein material by centrifugation to form a soluble fraction and residual solids,
• ki) concentrating and optionally diafiltering the soluble fraction to decrease the content of salt and/or other impurities in the soluble fraction and provide a first pulse protein hydrolyzate (retentate), having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis, which is substantially completely soluble throughout the pH range of about 2 to about 7 and which provides a lower astringency than the pulse protein material YP35-K28-16A YP701 when an acidic beverage containing the first pulse protein hydrolyzate is consumed,
• li) drying the concentrated and optionally diafiltered first pulse protein hydrolyzate (retentate),
• mi) washing the residual solids to provide a second pulse protein hydrolyzate having a protein content of at least about 60 wt % (N×6.25) d.b. and an improved Amino Acid Score, which is improved compared to the pulse protein material, wherein the washing is effected by mixing the residual solids with water and collecting the washed residual solids by centrifugation, and
• ni) drying the washed residual solids, or
• fii) adjusting the optionally concentrated, diafiltered and diluted pulse protein pulse protein solution in pH within the range of about 6.0 to about 8.0,
• gii) treating the pH adjusted pulse protein solution with a proteolytic enzyme to effect hydrolysis of the pulse protein,
• hii) the hydrolyzed pulse protein material is heat treated to inactivate the enzyme,
• iii) separating the hydrolyzed pulse protein material by centrifugation to form a soluble fraction and residual solids,
• jii) concentrating and optionally diafiltering the soluble fraction to decrease the content of salt and/or other impurities in the soluble fraction and provide a first pulse protein hydrolyzate (retentate), having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis, which is substantially completely soluble throughout the pH range of about 2 to about 7 and which provides a lower astringency than the pulse protein material YP35-K28-16A YP701 when an acidic beverage containing the first pulse protein hydrolyzate is consumed,
• kii) drying the concentrated and optionally diafiltered first pulse protein hydrolyzate (retentate),
• lii) washing the residual solids to provide a second pulse protein hydrolyzate having a protein content of at least about 60 wt % (N×6.25) d.b. and an improved Amino Acid Score, which is improved compared to the pulse protein material, wherein the washing is effected by mixing the residual solids with water and collecting the washed residual solids by centrifugation, and
• iii) drying the washed residual solids, or
• fiii) optionally adjusting the optionally concentrated, diafiltered and diluted pulse protein solution in pH within the range of about 1.5 to about 4.0,
• giii) treating the optionally pH adjusted pulse protein solution with a proteolytic enzyme to effect hydrolysis of the pulse protein,
• hiii) the hydrolyzed pulse protein material is heat treated to inactivate the enzyme,
• iiii) separating the hydrolyzed pulse protein material by centrifugation to form a soluble fraction and residual solids,
• jiii) concentrating and optionally diafiltering the soluble fraction to decrease the content of salt and/or other impurities in the soluble fraction and provide a first pulse protein hydrolyzate (retentate), having a protein content of at least about 60 wt % (N×6.25) on a dry weight basis, which is substantially completely soluble throughout the pH range of about 2 to about 7 and which provides a lower astringency than the pulse protein material YP35-K28-16A YP701 when an acidic beverage containing the first pulse protein hydrolyzate is consumed,
• kiii) drying the concentrated and optionally diafiltered first pulse protein hydrolyzate (retentate),
• liii) washing the residual solids to provide a second pulse protein hydrolyzate having a protein content of at least about 60 wt % (N×6.25) d.b. and an improved Amino Acid Score, which is improved compared to the pulse protein material, wherein the washing is effected by mixing the residual solids with water and collecting the washed residual solids by centrifugation, and
• miii) drying the washed residual solids.