Alpha-glucan mixture, its preparation and uses

Patent metadata

Field	Value
Publication number	US-11408019-B2
Application number	US-201615780706-A
Country	US
Kind code	B2
Filing date	Dec 2, 2016
Priority date	Dec 4, 2015
Publication date	Aug 9, 2022
Grant date	Aug 9, 2022

Abstract

An object of the present invention is to provide an α-glucan mixture in a preferable molecular weight range, which can be made into a transparent film with advantageous strength and water solubility when an edible film is made by using the α-glucan mixture without adding any plasticizer.The above object is solved by providing an α-glucan mixture, which is obtainable by a process comprising the steps of gelatinizing waxy starch and liquefying the resulting gelatinized waxy starch by allowing an amylase to act on it, having the following characteristics (1) and (2):(1) having the weight average molecular weight (Mw) in a range of 150 kDa to 3,000 kDa; and(2) having the value of dividing weight average molecular weight (Mw) with number average molecular weight (Mn), Mw/Mn, of 35.1 or lower.

First claim

The invention claimed is:

1. An α-glucan mixture, which is obtainable by a process comprising the steps of gelatinizing waxy starch and liquefying the resulting gelatinized waxy starch by allowing an amylase to act on it, having the following characteristics (1) to (3):
(1) having the weight average molecular weight (Mw) in a range of 150 kDa to 3,000 kDa;
(2) having the value of dividing weight average molecular weight (Mw) with number average molecular weight (Mn), Mw/Mn, of 35.1 or lower; and
(3) forming a hydrolyzate with isomaltose content of less than 22% by weight, on a dry solid basis of the hydrolyzate, when digested by isomaltodextranase (EC 3.2.1.94).

2. The α-glucan mixture of claim 1 , which contains a-glucan having an isomaltose structure at the non-reducing end.

3. The α-glucan mixture of claim 2 , wherein said α-glucan mixture forms isomaltose in an amount of over 3% by weight but less than 22% by weight, on a dry solid basis of the hydrolyzate, when digested by isomaltodextranase (EC 3.2.1.94).

4. The α-glucan mixture of claim 3 , wherein said waxy starch is waxy corn starch.

5. The α-glucan mixture of claim 3 , which further has the following characteristic:
a film obtained by steps of molding the α-glucan mixture without plasticizer and drying, with a thickness of 40 to 50 mu.m, exhibits a rupture strength of piercing of 2.0 N/mm 2 or higher when analyzed on a piercing test for rupture strength using an adaptor with a sectional area of 1 mm 2 .

6. The α-glucan mixture of claim 3 , which can be made into a homogeneous solution when dissolved into water by admixing with deionized water to give a solid concentration of 20% by weight and stirring at 30° C. for 15 min.

7. An edible film, which is obtainable by steps of molding the α-glucan mixture of claim 3 , without adding any plasticizer and drying and exhibits a rupture strength of piercing of 2.0 N/mm 2 or higher when analyzed on a piercing test for rupture strength using an adaptor with a sectional area of 1 mm 2 .

8. The α-glucan mixture of claim 2 , wherein said waxy starch is waxy corn starch.

9. The α-glucan mixture of claim 2 , which further has the following characteristic:
a film obtained by steps of molding the α-glucan mixture without plasticizer and drying, with a thickness of 40 to 50 mu.m, exhibits a rupture strength of piercing of 2.0 N/mm 2 or higher when analyzed on a piercing test for rupture strength using an adaptor with a sectional area of 1 mm 2 .

10. The α-glucan mixture of claim 2 , which can be made into a homogeneous solution when dissolved into water by admixing with deionized water to give a solid concentration of 20% by weight and stirring at 30° C. for 15 min.

11. An edible film, which is obtainable by steps of molding the α-glucan mixture of claim 2 , without adding any plasticizer and drying and exhibits a rupture strength of piercing of 2.0 N/mm 2 or higher when analyzed on a piercing test for rupture strength using an adaptor with a sectional area of 1 mm 2 .

12. The α-glucan mixture of claim 1 , wherein said waxy starch is waxy corn starch.

13. The α-glucan mixture of claim 1 , which further has the following characteristic:
a film obtained by steps of molding the a-glucan mixture without plasticizer and drying, with a thickness of 40 to 50 mu.m, exhibits a rupture strength of piercing of 2.0 N/mm 2 or higher when analyzed on a piercing test for rupture strength using an adaptor with a sectional area of 1 mm 2 .

14. The α-glucan mixture of claim 1 , which can be made into a homogeneous solution when dissolved into water by admixing with deionized water to give a solid concentration of 20% by weight and stirring at 30° C. for 15 min.

15. A process for producing the α-glucan mixture of claim 1 , comprising the steps of:
gelatinizing waxy starch by heating a waxy starch suspension with a solid concentration of 20% by weight; and
forming α-glucan mixture having the weight average molecular weight (Mw) in a range of 150 kDa to 3,000 kDa by allowing an amylase to act on the resulting gelatinized waxy starch.

16. The process of claim 15 , further comprising a step of allowing an α-glucosyltransferase, which acts on starch hydrolyzate and catalyzes α-1,6 transglucosylation reaction to the non-reducing end of the starch hydrolyzate, to act on the formed α-glucan mixture.

17. The process of claim 16 , wherein said α-glucosyltransferase is derived from a microorganism of the genus Bacillus or Arthrobacter and has the following characteristics (A) to (F):
(A) Action
Acting on maltose and/or α-1,4 glucan having a glucose polymerization degree of 3 or higher, catalyzing mainly α-1,4 transglucosylation reaction and α-1,6 transglucosylation reaction, and transferring glucose to the C-4 or C-6 hydroxyl group of the glucose residue at the non-reducing end;

(B) Molecular weight
90,000±10,000 daltons on SDS-polyacrylamide gel electrophoresis;

(C) Optimum temperature
About 50° C. when reacted at pH 6.0 for 30 min;

(D) Optimum pH
About pH 6.0 when reacted at 40° C. for 30 min;

(E) Thermal stability
Stable up to the temperature of 40° C. when incubated at pH 6.0 for 60 min;
and

(F) pH stability
Stable in the range of pH 4.0 to 8.0 when incubated at 4° C. for 24 hours.

18. An edible film, which is obtainable by the steps of molding the α-glucan mixture of claim 1 , without adding any plasticizer and drying and exhibits a rupture strength of piercing of 2.0 N/mm 2 or higher when analyzed on a piercing test for rupture strength using an adaptor with a sectional area of 1 mm 2 .

Assignees

• Hayashibara Co

Inventors

• Kishishita Seiichiro
• KANASHIMA Shoko
• Miyata Manabu
• Yamamoto Takuo
• Hino Katsuhiko
• Nishimoto Tomoyuki

Classifications

• A23P20/105

  Coating with compositions containing vegetable or microbial fermentation gums, e.g. cellulose or derivatives; Coating with edible polymers, e.g. polyvinyalcohol · CPC title

• A23L5/00

  Preparation or treatment of foods or foodstuffs, in general; Food or foodstuffs obtained thereby; Materials therefor · CPC title

• C12P19/14

  produced by the action of a carbohydrase {(EC 3.2.x)}, e.g. by alpha-amylase {, e.g. by cellulase, hemicellulase} · CPC title

• C08B37/0009

  alpha-D-Glucans, e.g. polydextrose, alternan, glycogen; (alpha-1,4)(alpha-1,6)-D-Glucans; (alpha-1,3)(alpha-1,4)-D-Glucans, e.g. isolichenan or nigeran; (alpha-1,4)-D-Glucans; (alpha-1,3)-D-Glucans, e.g. pseudonigeran; Derivatives thereof · CPC title

• A23L29/20

  containing gelling or thickening agents (marmalades, jams, jellies or other similar fruit or vegetable compositions A23L21/10) · CPC title