Crystallisation of beta-lactoglobulin using multiple protein feeds
The present invention relates to an improved method of producing beta-lactoglobulin (BLG) compositions by crystallisation of BLG. The invention makes use of at least two different BLG-containing protein feeds which are mixed to prepare a supersaturated protein solution in which BLG is crystallized. One of the protein feeds must have a pH of at least 5.6 and one of the protein feeds must have a pH of at most 5.4.
1 . A method of preparing an edible composition comprising beta-lactoglobulin (BLG), the method comprising the steps of:
a) preparing an initial protein solution comprising BLG, wherein said initial protein solution is supersaturated with respect to BLG and has a pH in the range of 5-6,
b) crystallising BLG in the supersaturated, initial protein solution in salting-in mode, thereby obtaining a BLG crystal-containing solution, and
c) separating BLG crystals from the remaining liquid of the BLG crystal-containing solution,
wherein step a) involves preparing the initial protein solution by mixing one or more type A protein feed(s) with one or more type B protein feed(s),
and wherein:
a “type A protein feed” is defined as a protein feed which comprises BLG and has a pH of at least 5.6, and
a “type B protein feed” is defined as a protein feed which comprises BLG and has a pH of at most 5.4.
2 . The method according to claim 1 wherein:
in relation to the one or more type A protein feed(s):
if only a single type A protein feed is used it has, or
if two or more type A protein feeds are used they would, if mixed, have a pH of at least 5.6, and
in relation to the one or more type B protein feed(s):
if only a single type B protein feed is used it has, or
if two or more type B protein feeds are used they would, if mixed, have a pH of at most 5.4.
3 . The method according to claim 1 , wherein:
in relation to the one or more type A protein feed(s):
if only a single type A protein feed is used it has, or
if two or more type A protein feeds are used they would, if mixed, have a pH of at least 6.0, and
in relation to the one or more type B protein feed(s):
if only a single type B protein feed is used it has, or
if two or more type B protein feeds are used they would, if mixed, have a pH of at most 5.0.
4 . The method according to claim 1 , wherein in relation to the one or more type A protein feed(s):
if only a single type A protein feed is used it has, or
if two or more type A protein feeds are used they would, if mixed, have a pH of in the range of 5.6-10.
5 . The method according to claim 1 , wherein in relation to the one or more type A protein feed(s):
if only a single type A protein feed is used it has, or
if two or more type A protein feeds are used they would, if mixed, have a pH of in the range of 6.0-8.
6 . The method according to claim 1 , wherein in relation to the one or more type B protein feed(s):
if only a single type B protein feed is used it has, or
if two or more type B protein feeds are used they would, if mixed, have a pH of in the range of 2-5.4.
7 . The method according to claim 1 , wherein in relation to the one or more type B protein feed(s):
if only a single type B protein feed is used it has, or
if two or more type B protein feeds are used they would, if mixed, have a pH of in the range of 4.0-5.0.
8 . The method according to claim 1 , wherein at least one of the one or more type A protein feed(s) does not contain BLG crystals and/or wherein at least one of the one or more type B protein feed(s) do not contain BLG crystals.
9 . The method according to claim 1 , wherein at least one of the one or more type A protein feed(s) is not supersaturated with respect to BLG and/or wherein at least one of the one or more type B protein feed(s) is not supersaturated with respect to BLG.
10 . The method according to claim 1 , wherein type A and type B protein feed(s) that do not contain BLG crystals contribute with at least 1% w/w of the BLG content of the initial protein solution.
11 . The method according to claim 1 , wherein type A and type B protein feed(s) that do not contain BLG crystals contribute with at least 50% w/w of the BLG content of the initial protein solution.
12 . The method according to claim 1 , wherein in relation to the one or more type A protein feed(s):
if only a single type A protein feed is used it has, or
if two or more type A protein feeds are used they would, if mixed, have a temperature of at most 60 degrees C.
13 . The method according to claim 1 , wherein in relation to the one or more type B protein feed(s):
if only a single type B protein feed is used it has, or
if two or more type B protein feeds are used they would, if mixed, have a temperature of at most 60 degrees C.
14 . The method according to claim 1 , wherein in relation to the one or more type A protein feed(s):
if only a single type A protein feed is used it comprises, or
if two or more type A protein feeds are used they would, if mixed, comprise at least 1% w/w BLG relative to the total weight of the one or more type A protein feed(s).
15 . The method according to claim 1 , wherein in relation to the one or more type B protein feed(s):
if only a single type B protein feed is used it comprises, or
if two or more type B protein feeds are used they would, if mixed, comprise at least 1% w/w BLG relative to the total weight of the one or more type B protein feed(s).
16 . The method according to claim 1 , wherein the initial protein solution comprises a total amount of the one or more type A protein feed(s) in the range of 1-99% w/w relative to the weight of the initial protein solution.
17 . The method according to claim 1 , wherein the initial protein solution comprises a total amount of the one or more type B protein feed(s) in the range of 1-99% w/w relative to the weight of the initial protein solution.
18 . The method according to claim 1 , wherein the initial protein solution comprises:
a total amount of type A protein feed(s) having a pH of 5.8-8 in the range of 5-90% w/w relative to the weight of the initial protein solution, and
a total amount of type B protein feed(s) having a pH of 3-5.2 in the range of 5-90% w/w relative to the weight of the initial protein solution.
19 . The method according to claim 1 , wherein the initial protein solution comprises:
a total amount of type A protein feed(s) having a pH of 6.0-8 in the range of 5-90% w/w relative to the weight of the initial protein solution, and
a total amount of type B protein feed(s) having a pH of 3-5.0 in the range of 5-90% w/w relative to the weight of the initial protein solution.
20 . The method according to claim 1 , wherein the one or more type A protein feed(s) and the one or more type B protein feed(s) contribute with at least 50% w/w of the protein content of the initial protein solution.
21 . The method according to claim 1 , wherein the one or more type A protein feed(s) and the one or more type B protein feed(s) contribute with at least 92% w/w of the protein content of the initial protein solution.
22 . The method according to claim 1 , wherein the one or more type A protein feed(s) and the one or more type B protein feed(s) contribute with at least 50% w/w of the solids content of the initial protein solution.
23 . The method according to claim 1 , wherein the one or more type A protein feed(s) and the one or more type B protein feed(s) contribute with at least 92% w/w of the solids content of the initial protein solution.
24 . The method according to claim 1 , wherein the one or more type A protein feed(s) and the one or more type B protein feed(s) contribute with at least 50% w/w of the weight of the initial protein solution.
25 . The method according to claim 1 , wherein the one or more type A protein feed(s) and the one or more type B protein feed(s) contribute with at least 92% w/w of the weight of the initial protein solution.
26 . The method according to claim 1 , wherein the degree of supersaturation of BLG of the initial protein solution is higher than both the degree of supersaturation of:
the type A protein feed if only a single type A protein feed is used, or
the type A protein foods, if combined, if two or more type A protein foods are used, and of:
the type B protein feed if only a single type B protein feed is used, or
the type B protein foods, if combined, if two or more type B protein feeds are used.