| 摘要 |
The invention provides a process for enabling the production of a particulate composition containing anhydrous crystalline ascorbic acid 2-glucoside that does not significantly cake even when the production yield of ascorbic acid 2-glucoside does not reach 35% by weight. The process for producing a particulate composition containing anhydrous crystalline ascorbic acid 2-glucoside, which comprises allowing a CGTase to act on a solution containing either liquefied starch or dextrin and L-ascorbic acid and then allowing a glucoamylase to act on the resulting solution to obtain a solution with an ascorbic acid 2-glucoside production yield of at least 27%, purifying the obtained solution to increase the ascorbic acid 2-glucoside content to a level of over 86% by weight, precipitating anhydrous crystalline ascorbic acid 2-glucoside by a controlled cooling method or pseudo-controlled cooling method, collecting the precipitated anhydrous crystalline ascorbic acid 2-glucoside, and ageing and drying the collected anhydrous crystalline ascorbic acid 2-glucoside. |
| 主权项 |
1. A process for producing a particulate composition comprising anhydrous crystalline 2-O-α-D-glucosyl-L-ascorbic acid, said process comprising the following steps (a) to (e):
(a) incubating an aqueous solution comprising cyclomaltodextrin glucanotransferase, ascorbic acid, and either liquefied starch or dextrin to obtain a reaction mixture and then further incubating the reaction mixture along with glucoamylase to obtain a resulting solution with a 2-O-α-D-glucosyl-L-ascorbic acid content of at least 27% but less than 35% by weight, on a dry solid basis; (b) purifying the resulting solution comprising 2-O-α-D-glucosyl-L-ascorbic acid to give a purified solution with a 2-O-α-D-glucosyl-L-ascorbic acid content of over 86% by weight, on a dry solid basis; (c) crystallizing 2-O-α-D-glucosyl-L-ascorbic acid from the purified solution in the presence of seed crystals in the amount of 0.1% to 5% (w/v) by a controlled cooling method or pseudo-controlled cooling method; (d) collecting the crystallized anhydrous 2-O-α-D glucosyl-L-ascorbic acid; and (e) ageing and drying the crystals to obtain the particulate composition which contains over 98.0% but below 99.9% by weight of 2-O-α-D-glucosyl-L-ascorbic has a degree of crystallinity of at least 90%, when calculated based on the powder X-ray diffraction profile of the particulate composition, and has a reducing power of the whole particulate composition of less than 1% by weight; wherein, in step (c), said controlled cooling method is defined by the equation T=T0−(T0−Tf)(t/τ)3, where “T” is the liquid temperature at the time “t”, “τ” is the operation time established for a crystallization step, “T0” is the liquid temperature at the initiation of crystallization, and “Tf” is the targeted liquid temperature at the termination of crystallization; and said pseudo-controlled cooling method is defined by the equation above, where the liquid temperature “T” at the time “t” is allowed to linearly or stepwisely decrease with the time “t” in order to keep the variation (T0−Tm) of the liquid temperature “T” at time “t=τ/2” to be at least 5% but less than 50% of the total temperature change (T0−Tf), with “Tm” being the liquid temperature at time “t=τ/2”. |
