FERMENTED MILK-BASED PRODUCT COMPRISING GALACTO-OLIGOSACCHARIDES AND METHODS THEREOF
The present invention relates to a fermented milk-based product comprising a combination of low levels of lactose and stable levels of galacto-oligosaccharides (GOS) produced in-situ and methods thereof.
1 . A method for producing a yogurt comprising galacto-oligosaccharides, wherein the method comprises
(a) treating a milk-based substrate comprising at least 1% w/w lactose with a beta-galactosidase enzyme to generate galacto-oligosaccharides;
(b) before or after said treating, fermenting the milk-based substrate until a pH below 5 is reached; and
(c) inactivating the beta-galactosidase enzyme by subjecting the fermented milk-based substrate comprising galacto-oligosaccharides having a pH below 5 to heat treatment at a temperature from 70° C. to 85° C.,
thereby producing the yogurt comprising galacto-oligosaccharides.
2 . The method according to claim 1 , further comprising storing the yogurt at a temperature of 15-37° C. and at a pressure of 1 atm.
3 . The method according to claim 1 , wherein the galacto-oligosacharides comprised in the yogurt are stable for at least 5 days when the yogurt is stored at a temperature of 15-37° C. and at a pressure of 1 atm.
4 . The method according to claim 1 , wherein the step of treating the milk-based substrate with a beta-galactosidase enzyme is carried out with from 0.1-10 g enzyme per L milk-based substrate.
5 . The method according to claim 1 , wherein the beta-galactosidase enzyme is a Bifidobacterium beta-galactosidase.
6 . The method according to claim 1 , wherein the step of inactivating the beta-galactosidase enzyme is carried out at a temperature from 72° C. to 80° C.
7 . The method according to claim 1 , wherein the step of inactivating the beta-galactosidase enzyme is carried out at a temperature from 70° C. to 75° C. for 5 seconds to 60 seconds.
8 . The method according to claim 1 , wherein the step of inactivating the beta-galactosidase is carried out at a temperature from 70° C. to 75° C. for 10 seconds to 60 seconds and at a pH of 4.3.
9 . The method according to claim 1 , wherein the yogurt is a post-pasteurization stirred yogurt or a post-pasteurization drinking yogurt.
10 . The method according to claim 1 , wherein the yogurt comprises at least 0.5% w/w galacto-oligosaccharides.
11 . A yogurt prepared by a process according to claim 1 , comprising at least 0.5% w/w galacto-oligosaccharides, and having a pH below 5.
12 . A yogurt comprising at least 0.5% w/w galacto-oligosaccharides and having a pH below 5, further comprising an inactivated beta-galactosidase enzyme.
13 . The yogurt according to claim 12 , wherein the galacto-oligosaccharides have a polymerization degree of at least 3.
14 . The yogurt according to claim 12 , wherein the yogurt is a post-pasteurization stirred yogurt or a post-pasteurization drinking yogurt.
15 . The yogurt according to claim 12 , wherein the galacto-oligosacharides are stable for at least 5 days when the yogurt is stored at a temperature of 15-37° C. and at a pressure of 1 atm.
16 . The method according to claim 1 , wherein the fermenting is carried out at 43° C.
17 . The method according to claim 1 , wherein the step of inactivating the beta-galactosidase enzyme is carried out at a temperature from 70° C. to 75° C.
18 . The method according to claim 5 , wherein the beta-galactosidase enzyme has at least 90% sequence identity to any one of SEQ ID NOs 1-15.
19 . The method according to claim 1 , wherein the yogurt comprises 0.5-4% w/w galacto-oligosaccharides.