JP2017051112A - Food modifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a food modifier for improving the properties of food and beverage products manufactured by processing starch-containing raw material.SOLUTION: The food and beverage modifier for processing starch-containing raw material by using α-glucosidase. The α-glucosidase acts upon carbohydrates selected from the group consisting of α-type oligosaccharides and α-type polysaccharides so as to produce carbohydrates having an α-1,2 bond and carbohydrates having an α-1,3 bond.SELECTED DRAWING: None

Description

  The present invention relates to a technique for improving food and drink using α-glucosidase. In particular, the present invention uses α-glucosidase that acts on α-type oligosaccharides and polysaccharides to produce saccharides having α-1,2 bonds and saccharides having α-1,3 bonds. TECHNICAL FIELD

  The value of food and drink is greatly influenced by its quality, but in recent years, the quality required for food and drink has increased in diversity. Among the quality of food and drink, the texture is one of the factors that greatly affect the value of food. In recent years, consumer demand for food health functions has also increased. Even in foods and beverages manufactured by processing raw materials containing starches, consumer demands for quality such as texture and health functionality are increasing, and the structure of starch and sugar binding patterns in foods and beverages Is a major factor affecting the quality of food and drink.

  Starch is composed of amylose in which glucose is linearly linked by α-1,4 bonds and amylopectin having a structure branched by α-1,6 bonds in the middle of the straight chain in which α-1,4 bonds are linked. It is a mixture. When water is added to starch and heated, it is gelatinized to a state called gelatinized starch. However, if the gelatinized starch is allowed to stand, water is separated, and a phenomenon called “starch aging” occurs. If the texture of food containing starch such as cooked rice or bread is left at room temperature or lower, it becomes harder with time, which is considered to be caused by aging of starch.

  The use of an enzyme has been proposed as a method for inhibiting starch aging. By causing the enzyme to act on the starch, effects such as improving the storage structure by improving the structure of the starch and suppressing the aging of the starch can be obtained. Transglucosidase (α-glucosidase derived from Aspergillus niger), which is known as α-glucosidase having transglycosylation activity and produces a carbohydrate mainly having a degree of polymerization one greater than that of the substrate, for example, It has been proposed to be used for the manufacture of cooked rice, rice noodles, bread, udon, potato salad (Patent Document 1), processed meat / fishery processed food (Patent Document 2), and modified starch (Patent Document 3). In addition, a method for producing rich, low-alcohol refined sake characterized by mainly containing non-fermentable oligosaccharides by adding α-amylase, the above-described transglucosidase, and acidic protease during sake brewing has been proposed. (Patent Document 4). However, the food texture improvement effect of all obtained food / beverage products is low, and it was inadequate for manufacturing a good quality food.

  Moreover, about the saccharide | sugar which has (alpha) 1, 2 bond, functionality (nonpatent literature 1), such as not being fermented by a cariogenic microbe, has a weak reducing power and weak Maillard reactivity.

  As a characteristic function of a carbohydrate having an α1,3 bond, a food flavor improver (patent document 5) that relaxes the “salt corner” of food containing salt and improves the preference under low salt, In addition to its use as a physical property improving agent such as a pigment fading prevention effect for food (Patent Document 6), as a physiological function, an immunostimulatory effect that induces the production of interleukin 12 when used in combination with bacteria derived from the genus Lactobacillus ( Patent Document 7) and a function that causes plants exposed to pathogenic bacteria to induce and accumulate phytoalexins having antibacterial activity in the plant body as an autoimmune action against the pathogenic bacteria (Patent Document 8) and the like are reported. Has been.

WO2005 / 096839 WO2008 / 156126 WO2011 / 021372 Japanese Patent Publication No.62-10635 JP-A-10-210949 JP 2000-189101 A JP-A-11-228425 JP-A-10-36210

Tomoyuki Nishimoto et al., Japanese Society for Applied Glycoscience 2001 Annual Meeting Abstracts, Vol. 48, 413 (2001)

  The subject of this invention is providing the technique which improves the characteristic about the food-drinks manufactured by processing the raw material containing starch. In particular, in the present invention, it acts on a saccharide selected from the group consisting of α-type oligosaccharides and α-type polysaccharides to generate saccharides having α-1,2 bonds and α-1,3 bonds. The object is to provide a technique for improving the properties of food and drink by using α-glucosidase.

  The present inventors have already found that α-glucosidase belonging to the genus Aspergillus produces carbohydrates having α-1,2 bonds and α-1,3 bonds (Japanese Patent Laid-Open No. 2011-177118). Issue gazette).

  As a result of further investigations by the present inventors, they acted on carbohydrates selected from the group consisting of α-type oligosaccharides and α-type polysaccharides, and have α-1,2 bonds and α-1,3 bonds. Surprisingly, it has been found that the characteristics of food and drink can be greatly improved by using an α-glucosidase that produces the carbohydrates it has, and the present invention has been completed.

  That is, the present invention includes, but is not limited to, the following aspects.

  The food improving agent which is one aspect of the present invention is a food improving agent for foods and drinks produced by processing starch-containing raw materials, which contains α-glucosidase, wherein the α-glucosidase is an α-type oligosaccharide And a saccharide selected from the group consisting of α-type polysaccharides and producing a saccharide having an α-1,2 bond and a saccharide having an α-1,3 bond. It is a food improver.

  The present invention may be for improving the quality of processed rice products, for improving the quality of processed wheat products, and for improving the quality of processed barley products. It may be for improving the quality of processed potatoes.

  In the present invention, the amino acid sequence encoding the α-glucosidase may have 60% or more identity with the amino acid sequence described in any one of SEQ ID NOs: 1 to 10.

In the present invention, the amino acid sequence encoding the α-glucosidase is
Sequence 1: FQSQY,
Sequence 2: LWIMNNEA,
Sequence 3: EYDTHNLYG,
Sequence 4: VGHWLGDN,
Sequence 5: GEPFL and
Sequence 6: FYDWYTG,
Any one or more sequences selected from the group consisting of:

  In the present invention, the α-glucosidase may be α-glucosidase derived from Aspergillus.

  Another aspect of the present invention is a method for improving a food or drink produced by processing a starch-containing raw material, which comprises allowing α-glucosidase to act on starch, wherein the α-glucosidase is an α-type oligo. A food or drink that acts on a saccharide selected from the group consisting of saccharides and α-type polysaccharides to produce a saccharide having an α-1,2 bond and a saccharide having an α-1,3 bond. This is an improved method.

Another aspect of the present invention is:
Treating starch with α-glucosidase;
Adding processed starch to processed foods,
A method for improving the quality of processed foods, comprising:
α-Glucosidase acts on a saccharide selected from the group consisting of α-type oligosaccharides and α-type polysaccharides to generate saccharides having α1,2 bonds and saccharides having α-1,3 bonds. This is a method for improving the quality of processed food.

  The present invention may be for improving the quality of processed meat products or processed fish products.

  Based on the present invention, it is possible to improve the properties of food and drink by using an α-glucosidase that produces a carbohydrate having α-1,2 bonds and α-1,3 bonds.

FIG. 1 is a graph showing the composition of di- and trisaccharide components in the reaction product obtained using the purified enzyme derived from Aspergillus niger ATCC 10254 obtained in Experimental Example 1-2. FIG. 2 shows a plasmid vector incorporating an Aspergillus niger CBS513.88 strain α-glucosidase (Accession no. XP_001389510) gene together with a promoter region of the translation elongation factor TEF1 derived from Aspergillus oryzae RIB40. FIG. FIG. 3 is a diagram showing conditions for measuring gelatinization characteristics performed in Experimental Example 2-1.

Raw materials containing starch (starch-containing raw materials)
The present invention relates to a food or drink produced by processing a raw material containing starch. In the present invention, starch is a storage substance present in plant tissues such as cereals, potatoes and beans, and is a water-insoluble glucan composed of D-glucose. Starch is composed of amylose, which is a chain molecule, and amylopectin that is divergently branched. The starch contained in the starch-containing raw material of the present invention is not particularly limited, but the degree of glucose polymerization is preferably 100 or more, more preferably 1,000 or more, and further preferably 10,000 or more.

  In the present invention, the raw material containing starch is not particularly limited, but grains such as rice, wheat, corn and barley, potatoes, sweet potatoes, potatoes such as cassava, beans such as soybeans and peas, and these And starch extracted from these raw materials by a known method. Examples of starch extracted by a known method include, but are not limited to, rice starch, wheat starch, potato starch, tapioca starch, and corn starch. Furthermore, the processed starch etc. which performed the physical process or the chemical process individually or in combination of 2 or more types to the starch extracted by the well-known method are mentioned. Examples of physically processed processed starch include pregelatinized starch and wet heat-treated starch. Examples of chemically processed processed starch include etherified derivatives such as hydroxypropyl starch and esters such as acetate starch. And cross-linked derivatives such as phosphoric acid cross-linked starch.

Food / beverage products In the present invention, the food / beverage products are not particularly limited as long as they are produced by processing raw materials containing starch, and examples thereof include processed cereal products, processed potato products, processed legume products, and the like. Moreover, the food / beverage products which processed the raw material containing the starch extracted by the said well-known method are also contained. Examples of processed cereal products include processed rice products (boiled rice, rice cake, sake, amazake, Japanese sweets made from rice flour, etc.), processed wheat products (bread, noodles, Chinese buns and dumpling skins, visa dough, pie dough, Baked confectionery, fresh confectionery, etc.), processed barley products (bread, beer, beer-like beverages, etc.), and processed corn products (corn meal, corn flakes, corn whiskey, etc.), but are not limited thereto. Examples of processed potato products include, but are not limited to, potato processed products (mashed potatoes, french fries, hashed potatoes, gnocchi, potato chips, etc.) and sweet potato processed products (sweet potatoes, imoyokan, etc.). In addition, the food and drink of the present invention are processed by subjecting starch extracted by a known method to the α-glucosidase of the present invention, followed by physical treatment or chemical treatment alone or in combination of two or more. Starch is also included.

α-Glucosidase The present invention acts on a carbohydrate selected from the group consisting of α-type oligosaccharides and α-type polysaccharides, and generates α-1,2 bonds and α-1,3 bonds. It relates to the use of α-glucosidase that can be produced. In the present invention, α-glucosidase is allowed to act directly on the starch itself contained in the starch-containing raw material, thereby changing the properties of the starch in the raw material. The starch having a changed property has a glucose polymerization degree of preferably 100 or more, more preferably 1,000 or more, and still more preferably 10,000 or more. The food and drink produced using the raw material containing starch whose properties have changed have higher quality as food and drink than the food and drink produced using raw materials containing starch whose properties are not changed. For example, according to the present invention, it is possible to produce a softer food than using a raw material containing starch whose properties are not changed.

  In the present invention, the α-type oligosaccharide refers to a disaccharide to 9-saccharide carbohydrate having an α-glucoside bond in the molecule. Examples of α-type oligosaccharides include maltose, cordobiose, nigerose, isomaltose, trehalose, maltotriose, panose, isomaltotriose, maltotetraose, isomalttetraose, maltopentaose, maltohexaose, malto Although heptaose, (alpha) -cyclodextrin, (beta) -cyclodextrin, (gamma) -cyclodextrin etc. are mentioned, It is not limited to these.

  In the present invention, the α-type polysaccharide refers to a saccharide having 10 or more sugars having an α-glucoside bond in the molecule. Examples of α-type polysaccharides include, but are not limited to, glycogen, dextran, amylose, soluble starch and the like.

  The α-glucosidase used in the present invention can produce a carbohydrate having an α-1,2 bond and an α-1,3 bond. A saccharide having an α-1,2 bond refers to a saccharide having an α-1,2 bond in the molecule, and a saccharide having an α-1,3 bond is an α-1,3 in the molecule. A carbohydrate having a bond. Whether or not a carbohydrate has an α-1,2 bond or an α-1,3 bond is determined by, for example, NMR analysis, methylation analysis (Journal of Biochemistry 55, 205, 1964), etc. Can do.

The α-glucosidase used in the present invention is not limited to the organism from which it is derived,
Filamentous fungi (Absidia, Acremonium, Actinomadura, Alternaria, Aspergillus, Chaetomium, Coprinus, Coriolus, Geotrichum, Humicola, Monascus, Mortierella, Mucor, Nocardiopsis, Oidiodendron, Penicillium, Rhizomucor, Rhizopustic, Trichoderma, Ver.
Basidiomycetes (Coliolus, Corticium, Cyathus, Irpexs, Polyporus, Pycnoporus, Trametes, etc.),
Bacteria (Aeromonas, Agrobacterium, Alcaligenes, Agrobacterium, Alteromonas, Arthrobacter, Bacillus, Brevibacterium, Chromobacterium, Corynebacterium, Crypnohectria, Erwinia, Escherichia, Flavobacterium, Klebsiella, Lactobacillus, Lactococactus, Leuconimetactoccus, Leuconostactus Serratia, Streptococcus, Streptoverticillium, Sulfolobus, Thermus, Xanthomonas etc.)
Actinomycetes (Actinomadura, Actinomyces, Actinoplanes, Amycolatopsis, Eupenicillium, Nocardiopsis, Streptomyces, Thermomonospora, etc.)
A strain having a use example in food production such as yeast (Aureobasidium, Candida, Irpex, Kluyveromyces, Pycnoporus, Saccharomyces, Trichosporon, etc.) is desirable.

  The α-glucosidase used in the present invention is selected from the group consisting of, for example, filamentous fungi belonging to the genus Aspergillus (hereinafter simply referred to as Aspergillus), from the group consisting of α-type oligosaccharides and α-type polysaccharides. It can be obtained as an enzyme that acts on a saccharide and produces a saccharide having an α-1,2 bond and a saccharide having an α-1,3 bond.

The α-glucosidase used in the present invention is preferably an enzyme further having the following enzyme chemical properties. Thereby, even when manufacturing food-drinks industrially on high temperature conditions or acidic conditions, the quality of food-drinks can be improved efficiently.
(1) Temperature stability: pH 4.0, maintained for 30 minutes, remaining at 90% or more of initial activity at 65 ° C .;
(2) pH stability: pH 3.0 to 5.5 at 4 ° C., maintained for 24 hours.

Moreover, the α-glucosidase used in the present invention may be an enzyme having the following enzyme chemical properties:
(3) Substrate specificity: Decomposes α-glucooligosaccharides such as maltose, nigerose, cordobiose, malto-oligosaccharide and non-reducing end α-glucoside bond of α-glucan such as amylose and soluble starch to release glucose. Also has activity of degrading sucrose;
(4) Molecular weight: 48,000 daltons and 59,000 daltons by SDS-polyacrylamide gel electrophoresis;
(5) Isoelectric point: pI 4.9 to 5.5 (central value 5.2);
(6) Optimal temperature: pH 4.0, reaction for 10 minutes, 65 ° C .;
(7) Optimal pH: pH 3.5 at 50 ° C. for 10 minutes reaction.

  Examples of the genus Aspergillus for obtaining α-glucosidase used in the present invention include Aspergillus sojae, Aspergillus oryzae, Aspergillus nidulans, and Aspergillus niger. Bacteria belonging to Aspergillus kawachii and Aspergillus aculeatus can be preferably used. Among them, Aspergillus nijur ATCC10254, Aspergillus nijur NBRC4043, Aspergillus nijur CBS513.88, Aspergillus nijur ATCC1015, Aspergillus nijur NBRC4066, Aspergillus oryzae RIB40, Aspergillus oryzalis 163 Aspergillus acuretus ATCC16872 strain, Aspergillus soya NBRC4239 strain, etc. are mentioned as suitable strains.

  The aforementioned Aspergillus spp. Is cultured using a known culture method such as liquid culture and solid culture, and an enzyme having α-glucosidase activity is collected from the culture by a known method and used in the present invention. α-Glucosidase can be obtained.

  The α-glucosidase used in the present invention is an amino acid sequence of α-glucosidase derived from Aspergillus nidu CBS513.88 (Accession no .: XP_001389510, SEQ ID NO: 1), α-glucosidase derived from Aspergillus nidu ATCC1015 (Accession no. .: EHA26885, SEQ ID NO: 2), Aspergillus kawachi IFO4308-derived α-glucosidase (Accession no .: GAA87366, SEQ ID NO: 3), α-glucosidase having the sequence described in SEQ ID NO: 4, Aspergillus nidu Α-glucosidase derived from NBRC4066 strain (SEQ ID NO: 5), α-glucosidase derived from Aspergillus nidulans ATCC38163 strain (Accession no .: ABF50846, SEQ ID NO: 6), α-glucosidase derived from Aspergillus oryzae RIB40 strain (Accession no. : XP_001818060, SEQ ID NO: 7), Aspergillus nidulans ATCC Α-glucosidase derived from 38163 strain (Accession no .: ABF50883, SEQ ID NO: 8), α-glucosidase derived from Aspergillus acuretas ATCC16872 strain (Accession no .: Aacu16872_025147, SEQ ID NO: 9), or derived from Aspergillus soja NBRC4239 Based on α-glucosidase (SEQ ID NO: 10), it preferably has 60% or 65% identity, more preferably 70% or 75% identity, more preferably 80%, 85%, 90% % Or 95% or more, and more preferably 60% or more based on the amino acid sequence of α-glucosidase (Accession no .: XP_001389510, SEQ ID NO: 1) derived from Aspergillus nidu CBS513.88 strain Most preferably, they have identity.

The α-glucosidase used in the present invention preferably contains any one or more sequences selected from the group consisting of the following sequences 1 to 6 in the amino acid sequence.
Sequence 1: FQSQY
Array 2: LWIMNNEA
Sequence 3: EYDTHNLYG
Array 4: VGHWLGDN
Sequence 5: GEPFL
Sequence 6: FYDWYTG
The percent identity between two amino acid sequences can be determined by visual inspection and mathematical calculation. The percent identity can also be determined using a computer program. Examples of such computer programs include BLAST, FASTA (Altschul et al., J. Mol. Biol., 215: 403-410 (1990)), and ClustalW (http://www.genome.jp/tools/clustalw). /) Etc., and default parameters can be used. Various conditions (parameters) for identity searches using the BLAST program are described in “Altschul et al. (Nucl. Acids. Res., 25, p.3389-3402, 1997)”. US Biotechnology Information Center (NCBI) and DNA Data Bank of Japan (DDBJ) website (BLAST Manual, Altschul et al. NCB / NLM / NIH Bethesda, MD 20894). It can also be determined using a program such as genetic information processing software GENETYX (manufactured by Genetics), DNASIS Pro (manufactured by Hitachi Software), Vector NTI (manufactured by Infomax).

  A specific alignment scheme that juxtaposes multiple amino acid sequences can also show a match of a specific short region of the sequence, so even if there is no significant relationship between the full length sequences of the sequences used, In such a region, a region having a very high specific sequence identity can also be detected. In addition, the BLAST algorithm can use the BLOSUM62 amino acid scoring matrix, but the following can be used as selection parameters: (A) Segments of query sequences with low composition complexity (Wootton and Federhen's Determined by the SEG program (Computers and Chemistry, 1993); Wootton and Federhen, 1996 “Analysis of compositionally biased regions in sequence databases” Methods Enzymol., 266: 544-71 Including filters to mask segments consisting of short-period internal repeats (determined by the XNU program of Claverie and States (Computers and Chemistry, 1993)), and (B) the database Statistical significance threshold for reporting fits to sequences, or E-score According to the statistical model of Karlin and Altschul, 1990, the expected probability of a match found by chance only; if the statistically significant difference due to a match is greater than the E-score threshold, this match is not reported .

  A protein comprising an amino acid sequence having 60% or more identity with the amino acid sequence represented by any one of SEQ ID NOs: 1 to 10 can be appropriately prepared by a known technique. For example, any one of SEQ ID NOs: 1 to 10 1 or a plurality of amino acid sequences represented by (for example, 1 to 190, 1 to 90, 1 to 50, 1 to 30, 1 to 25, 1 to 20, 1 to 15, more preferably (10, 9, 8, 7, 6, 5, 4, 3, 2, or 1) amino acids may be deleted, substituted or added.

  Of the above, the substitution is preferably a conservative substitution. A conservative substitution is the replacement of a particular amino acid residue with a residue having similar physicochemical characteristics, but any substitution that does not substantially change the structural characteristics of the original sequence. For example, any substitution may be made so long as the substituted amino acid does not destroy the helix present in the original sequence or other types of secondary structures characterizing the original sequence.

  Conservative substitutions are generally introduced by biological synthesis or chemical peptide synthesis, but preferably by chemical peptide synthesis. In this case, the non-natural amino acid residue may be included in the substituent, and the reversed type or the same region in which the non-substituted region is reversed in the peptidomimetic or amino acid sequence is reversed. Inverted types are also included.

In the following, amino acid residues are classified and exemplified for each substitutable residue, but the substitutable amino acid residues are not limited to those described below.
Group A: leucine, isoleucine, norleucine, valine, norvaline, alanine, 2-aminobutanoic acid, methionine, O-methylserine, t-butylglycine, t-butylalanine and cyclohexylalanine Group B: aspartic acid, glutamic acid, isoaspartic acid, Isoglutamic acid, 2-aminoadipic acid and 2-aminosuberic acid group C: asparagine and glutamine group D: lysine, arginine, ornithine, 2,4-diaminobutanoic acid and 2,3-diaminopropionic acid group E: proline, 3 -Hydroxyproline and 4-hydroxyproline group F: serine, threonine and homoserine Group G: phenylalanine and tyrosine In the case of non-conservative substitution, one member of the above types is exchanged for another type of member. In this case, it is preferable to consider the amino acid hydropathic index (hydropathic amino acid index) in order to retain the biological function of the protein used in the present invention (Kyte et al., J. Mol). Biol., 157: 105-131 (1982)).

  In the case of non-conservative substitution, amino acid substitution can be performed based on hydrophilicity.

  In the present specification and drawings, bases and amino acids and their abbreviations follow IUPAC-IUB Commission on Biochemical Nomenclature or, for example, Immunology-A Synthesis (2nd edition, supervised by ES Golub and DR Gren, Sinauer Associates, Mass.) Based on abbreviations commonly used in the industry, such as those described in Sunderland (1991). In addition, when there is an optical isomer with respect to an amino acid, L form is shown unless otherwise specified.

  The stereoisomers of the above amino acids such as D-amino acids, unnatural amino acids such as α, α-disubstituted amino acids, N-alkyl amino acids, lactic acid, and other unconventional amino acids are also used in the present invention. Can be a component of

  As described above, a protein comprising an amino acid sequence in which one or more amino acids are deleted, substituted, or added in the amino acid sequence represented by any of SEQ ID NOs: 1 to 10 is “Molecular Cloning, A Laboratory Manual 3rd”. ed. "(Cold Spring Harbor Press (2001))," Current Protocols in Molecular Biology "(John Wiley & Sons (1987-1997)," Kunkel (1985) Proc. Natl. Acad. Sci. USA 82: 488-92 , Kunkel (1988) Method. Enzymol. 85: 2763-6, etc.] and the like, and such mutations such as deletion, substitution or addition of amino acids. For example, a mutant introduction kit using a site-directed mutagenesis method such as the Kunkel method or the Gapped duplex method, for example, QuikChangeTM Site-Directed Mutagenesis Kit (Stratagene) , GeneTailorTM Site-Directed Mutagenesis S ystem (manufactured by Invitrogen), TaKaRa Site-Directed Mutagenesis System (Mutan-K, Mutan-Super Express Km, etc .: manufactured by Takara Bio Inc.) and the like can be used.

  In addition to the site-directed mutagenesis method described above, a gene can be used as a method for introducing a deletion, substitution, or addition of one or more amino acids into a protein amino acid sequence while retaining its activity. Examples thereof include a method of treating with a mutation source and a method of ligating after selectively cleaving a gene to remove, substitute or add selected nucleotides.

  The protein notation used herein is based on standard usage and notation commonly used in the art, with the left direction being the amino terminal direction and the right direction being the carboxy terminal direction.

  One skilled in the art can design and generate suitable variants of the α-glucosidase described herein using techniques known in the art. For example, by targeting a region that is considered to be less important for the biological activity of the α-glucosidase used in the present invention, the structure of the protein used in the present invention is changed without impairing the biological activity. Can do. Appropriate regions in the protein molecule can be identified. Residues and regions conserved among similar proteins can also be identified. Furthermore, conservative amino acid substitutions may be made in regions believed to be important for the biological activity or structure of the protein used in the present invention without compromising biological activity and without adversely affecting the polypeptide structure of the protein. Can also be introduced.

  In addition, a protein comprising an amino acid sequence having 60% or more identity with the amino acid sequence represented by any one of SEQ ID NOs: 1 to 10 may be isolated from a microorganism such as Aspergillus having α-glucosidase activity. , By using a publicly available sequence database (for example, NCBI database http://www.ncbi.nlm.nih.gov/), the amino acid sequence represented by any one of SEQ ID NOs: 1 to 10 has an identity of 60% or more. A microorganism having an amino acid sequence having the amino acid sequence may be searched and isolated from the microorganism. In addition, as will be described later, a nucleic acid encoding α-glucosidase is cloned from Aspergillus, and based on the nucleic acid, the amino acid sequence represented by any one of SEQ ID NOs: 1 to 10 has an identity of 60% or more. You may obtain the protein which consists of an amino acid sequence which has. Further, as will be described later, using a publicly available sequence database (for example, NCBI database http://www.ncbi.nlm.nih.gov/), a nucleic acid encoding α-glucosidase is searched, and the nucleic acid is detected. Based on the amino acid sequence represented by any one of SEQ ID NOs: 1 to 10, a protein comprising an amino acid sequence having 60% or more identity may be obtained.

  A person skilled in the art identifies residues of peptides that are important for the biological activity or structure of the protein used in the present invention and are similar to the peptides of the proteins, and compares the amino acid residues of the two peptides. So-called structure-function studies that predict which residues in proteins similar to those used in the present invention are amino acid residues corresponding to amino acid residues important for biological activity or structure. It can be carried out. Furthermore, by selecting a chemically similar amino acid substitution of the amino acid residue predicted in this way, a mutant that retains the biological activity of the protein used in the present invention can be selected. Moreover, those skilled in the art can analyze the three-dimensional structure and amino acid sequence of the mutant of this protein. Furthermore, the alignment of amino acid residues with respect to the three-dimensional structure of a protein can be predicted from the obtained analysis results. Amino acid residues predicted to be on the protein surface may be involved in important interactions with other molecules, but those skilled in the art will be able to do this based on the analysis results described above. Mutants can be made that do not change the amino acid residues predicted to be on the surface of various proteins. Furthermore, those skilled in the art can also produce mutants that substitute only one amino acid residue among the amino acid residues constituting the protein used in the present invention. Such mutants can be screened by known assay methods and information on individual mutants can be collected. Thereby, when the biological activity of the mutant in which a specific amino acid residue is substituted is reduced compared to the biological activity of the protein used in the present invention, such a biological activity is exhibited. The usefulness of the individual amino acid residues constituting the protein used in the present invention by comparing the cases in which the protein is used in the present invention. Can be evaluated. In addition, those skilled in the art will recognize amino acid substitutions that are undesirable as variants of the protein used in the present invention, either alone or in combination with other mutations, based on information collected from such routine experiments. Can be easily analyzed.

  As the carbon source of the medium used for culturing Aspergillus, for example, glucose, fructose, sucrose, lactose, starch, glycerin, dextrin, lecithin and the like are used alone or in combination, and as the nitrogen source Any of organic and inorganic nitrogen sources can be used. Among them, for example, peptone, yeast extract, soybean, kinako, rice bran, corn steep liquor, meat extract, casein, amino acid, etc. are used as the organic nitrogen source. On the other hand, as the inorganic nitrogen source, ammonium sulfate, ammonium nitrate, ammonium phosphate, diammonium phosphate, ammonium chloride and the like are used. Furthermore, examples of inorganic salts and micronutrients added to such a medium include sodium, magnesium, potassium, iron, zinc, calcium, manganese salts, vitamins, and the like. Moreover, it is also possible to use natural products, such as wheat bran, as a culture medium component containing said various components.

  The culture of Aspergillus is generally carried out at a temperature of 10 to 40 ° C., preferably a culture temperature of 25 to 30 ° C. is advantageously employed, and the medium pH may be 2.5 to 8.0. . The necessary culture period varies depending on the bacterial cell concentration, medium pH, medium temperature, medium composition, etc., but is usually about 3 to 9 days, and when the target α-glucosidase reaches the maximum. Then, the culture is stopped.

  Thus, after culture | cultivating Aspergillus genus microbe, (alpha) -glucosidase used by this invention is collect | recovered. The activity of α-glucosidase used in the present invention is found in both the cells of the culture and the medium, and can be purified and used by a known method. As an example, the crude enzyme solution obtained by concentrating the processed product of the culture solution is purified by collecting the fraction with high glucosidase activity by column chromatography or the like, and then the purified fraction is purified by Native-polyacrylamide gel electrophoresis. A single purified α-glucosidase can be obtained by subjecting to electrophoresis (for example, “PhastSystem” manufactured by GE Healthcare) and collecting and purifying a single band.

The modification | reformation of the food / beverage products which use (alpha) -glucosidase This invention relates to the improvement method of the food / beverage products obtained by processing the raw material containing starch using said (alpha) -glucosidase. By changing the characteristics of starch according to the present invention, the texture and taste of food and drink can be improved.

  The starch having changed properties obtained by the present invention has a glucose polymerization degree of preferably 100 or more, more preferably 1,000 or more, and further preferably 10,000 or more, and α-1,2 bond and α-1,3 bond. It is preferable to have.

  In the present invention, in consideration of the purpose or effect, α-glucosidase may be applied at any stage of the production of food and drink that processes a raw material containing starch. For example, what made (alpha) -glucosidase act on the raw material of food-drinks may be used for the process of the subsequent manufacture or process. Moreover, you may use for the process of the subsequent manufacture or processing what made alpha-glucosidase act on the intermediate product or intermediate processed product of food-drinks. Further, α-glucosidase may be added at the final stage of the production or processing of the food or drink, and the α-glucosidase may act until the food or drink is used for consumers.

  Moreover, in this invention, you may add what processed the raw material containing starch with (alpha) -glucosidase to processed food. The processed food is not particularly limited as long as it is a food obtained by subjecting the raw material to some kind of processing, and examples thereof include livestock processed foods, marine processed foods, milk processed foods, seasonings and the like.

  Furthermore, this invention is the foodstuff improving agent for food-drinks containing the said alpha-glucosidase in one aspect. The food improver for food and drink according to the present invention contains the α-glucosidase, and can improve the properties of the food and drink manufactured from the raw material containing starch. The food improving agent of the present invention may contain additional components such as excipients, preservatives, flavoring agents, antioxidants, and vitamins as long as the effects of the α-glucosidase are not impaired.

  The food improver of the present invention may contain 1 to 99% of the above α-glucosidase as a dry weight, may contain 5% to 80%, and may contain 10% to 50%. .

  The food improver of the present invention can be used for various foods and drinks as a food texture and physical properties improver after preparation and after sterilizing treatment as necessary.

  Hereinafter, the present invention will be described more specifically with reference to experimental examples, but the present invention is not limited to the following experimental examples. Unless otherwise specified, in this specification, the concentration and the like are based on weight, and the numerical range is described as including the end points.

Experimental Example 1: Acquisition of an enzyme that produces a carbohydrate having an α-1,2 bond and an α-1,3 bond (Experimental Example 1-1) Analytical method 1) Analytical method of α-glucosidase activity Using maltose as a substrate The hydrolysis activity was evaluated. Specifically, 10 μL of a 5% maltose aqueous solution and 20 μL of 100 mM acetate buffer (pH 4.0) are added to a 70 μL sample, reacted at 50 ° C. for 10 minutes, and then treated in a boiling bath for 5 minutes. The reaction was stopped. The amount of glucose produced in the reaction solution was measured with Glucose CII Test Wako (manufactured by Wako Pure Chemical Industries). The amount of enzyme that decomposes 1 μmol of maltose per minute was defined as 1 U.

2) Analytical method of di- and trisaccharide components Of disaccharide and trisaccharide components in a sample, oligosaccharides having α-1,2, α-1,3, α-1,4, α-1,6 linkages. The composition was calculated by subjecting the sample to analysis using an amino column under the following conditions. Each peak was identified by comparison with the elution time of a standard sugar analyzed in advance under the same conditions.
Standard sugar:
Commercially available reagents were used as standard sugars for disaccharides, and commercially available reagents or compositions obtained by the following procedures were used as standard sugars for trisaccharides. Nigerotriose and nigerosyl glucose were prepared according to the procedure described in Biochimica et Biophysica Acta Vol. 1700, page 189, 2004, and used as standard sugars. Kojibiosyl glucose was prepared as a standard sugar according to the method described in JP-A No. 2003-169665.
HPLC measurement conditions:
Column: Unison UK-Amino 250 x 3mm (Intact)
Column temperature: 50 ° C
Solvent gradient:

(Experimental example 1-2) Production and purification of α-glucosidase derived from Aspergillus niger ATCC10254 strain α-glucosidase derived from Aspergillus niger ATCC10254 strain described in JP2011-177118A is as follows. Prepared.

  As media, starch: 2%, peptone: 0.25%, yeast extract: 0.25%, soybean flour: 1%, monopotassium phosphate: 0.03%, magnesium sulfate: 0.01%, calcium chloride: Prepare a solution containing 0.01% and sodium chloride: 0.01% and pH 6.5, put 100 mL of the medium into a 500 mL Erlenmeyer flask and sterilize by steam, and then remove Aspergillus niger ATCC 10254 strain. Inoculated and cultured with shaking at 30 ° C. for 3 days.

  Dilute the above seed 80 times with sterilized water, add 10 mL of it into a 500 mL Erlenmeyer flask, add 10 g of wheat bran that has been sterilized by autoclaving, and stir well so that the water content becomes uniform. The solid culture was performed for 4 days. After completion of the culture, the wheat bran was washed with 100 g of sterilized water, and centrifuged at 16,000 × g for 30 minutes at 4 ° C. to obtain a culture solution from which insoluble matters were removed.

  The obtained culture solution was concentrated, and the following four steps of chromatographic separation were performed.

  (A) Anion exchange chromatography (first time): The culture solution was replaced with 20 mM sodium acetate buffer pH 5.5 by ultrafiltration, and the solution passed through a 0.2 μm filter was used as the enzyme stock solution. The separation resin was TOYOPEARL DEAE-650M (manufactured by Tosoh Corporation), and the amount of resin (hereinafter referred to as CV) was 100 mL.

  Elution was performed using a linear concentration gradient (8 CV) of 0 to 0.4 M sodium chloride using 20 mM sodium acetate buffer pH 5.5 as an initial buffer. The eluate was analyzed according to the method of (Experimental Example 1-1) and 1), and fractions containing maltose decomposition activity were collected.

  (B) Anion exchange chromatography (second time): The fraction obtained in the step (A) is replaced with the same initial buffer as in (A) by ultrafiltration, and again separated by an anion exchange resin. went. CV = 25 mL, eluting with a linear concentration gradient of 0 to 0.25 M sodium chloride (10 CV), the eluate was analyzed according to the method of (Experimental Example 1-1), 1), and maltose decomposition Fractions containing activity were collected.

  (C) Gel filtration chromatography: The fraction obtained in the step (B) was fractionated by gel filtration chromatography. The fraction obtained in the step (B) was replaced with 20 mM acetate buffer pH 5.5 containing 0.2 M sodium chloride by ultrafiltration and simultaneously concentrated to 1 mL. Fractions were applied to a column equilibrated with the same buffer. The obtained fraction was analyzed according to the method of (Experimental Example 1-1) and 1), and the fraction containing maltose-degrading activity was collected. For the fractionation, a column in which two HiLoad 16/60 Superdex 200 pg (manufactured by GE Healthcare Japan) and one HiLoad 16/60 Superdex 75 pg (manufactured by GE Healthcare Japan) were connected was used.

  (D) Isoelectric focusing (chromatographic focusing): The fraction obtained in the step (C) was collected and chromatofocused. MonoP 5/200 GL (manufactured by GE Healthcare Japan) was used as the column. The initial buffer is 25 mM histidine-hydrochloric acid buffer pH 5.5, and the elution buffer is Polybuffer 74-hydrochloric acid buffer pH 3.5 (manufactured by GE Healthcare Japan) with a gradient of pH 5.5 to 3.5. did. The eluate was analyzed according to the method of (Experimental Example 1-1) and 1), and fractions containing maltose decomposition activity were collected. The obtained fraction was used as a purified enzyme for α-glucosidase.

(Experimental example 1-3) Analysis of maltose transfer product by α-glucosidase derived from Aspergillus niger ATCC10254 strain Purified enzyme derived from Aspergillus niger ATCC10254 strain obtained in (Experimental example 1-2) 0.5 mL (0.9 U / mL) was allowed to act on 1 mL of 45% maltose (final concentration 30%), reacted at 55 ° C. for 48 hours, and then heated in a boiling bath for 10 minutes to deactivate the enzyme. The obtained reaction product was analyzed for the composition of the di- and trisaccharide components according to the method of (Experimental Example 1-1) and 2). The results are shown in FIG. Carbohydrates having α-1,2 bonds and α-1,3 bonds were observed in the reaction product.

(Experimental Example 1-4) Production and purification of α-glucosidase derived from Aspergillus niger NBRC4043 strain and analysis of transferred product Aspergillus niger NBRC4043 strain described in JP-A-2011-177118 is cultured. A purified enzyme of α-glucosidase was prepared from the obtained culture broth. The purification method of α-glucosidase was the same as the purification method performed in (Experimental Example 1-2). Using the purified enzyme thus obtained, the transferred product in the case where maltose was used as a substrate was analyzed in the same manner as in the analysis method performed in (Experimental Example 1-3). The reaction product obtained using α-glucosidase derived from Aspergillus niger NBRC4043 contains α-glucosidase in the same manner as the reaction product obtained using α-glucosidase derived from Aspergillus niger ATCC10254. Carbohydrates having 1,2 bonds and α-1,3 bonds were observed.

(Experimental Example 1-5) Production of a genetically modified strain that strongly expresses α-glucosidase derived from Aspergillus niger CBS513.88 strain (Accession no. XP — 001389510) The present inventors disclosed in JP2011-177118A Aspergillus niger ATCC 10254 strain-derived α-glucosidase has been confirmed to contain the following amino acid sequence groups (a) to (e).
Sequence (a): LLVEYQTDERLHVMIYDADEVYQVPESVLPR,
Sequence (b): TWLPDDPYVYGLGEHSDPMR,
Sequence (c): IPLETMWTDIDYMDKR,
Sequence (d): VFTLDPQR,
Sequence (e): WASLGAFYTFYR
As an α-glucosidase having all five of the above-mentioned sequence groups, a gene that strongly expresses α-glucosidase (Accession no. XP_001389510) derived from Aspergillus niger CBS513.88 strain described in JP2011-177118A A recombinant strain was produced. A PCR product obtained by amplifying from the start codon of the DNA encoding the amino acid sequence of Aspergillus niger CBS513.88 strain-derived α-glucosidase (Accession no. XP_001389510) to 300 bp downstream of the start codon so as to include a terminator , PPTR II digested with restriction enzymes Kpn I and Hind III together with the promoter region of translation elongation factor TEF1 derived from Aspergillus oryzae RIB40 as a high expression promoter using In Fusion HD Cloning Kit (Clontech) The plasmid vector was constructed by introducing the product into Takara Bio. The plasmid design is shown in FIG. Then, a protoplast-PEG method (Agricultural and Biological Chemistry Vol. 51, page 2549, 1987) was carried out using Aspergillus nidulans ATCC38163 as a host to produce a genetically modified strain.

(Experimental Example 1-6) Production of α-glucosidase derived from Aspergillus niger CBS513.88 strain (Accession no. XP — 001389510) and analysis of transferred product Recombinant strain prepared in (Experimental Example 1-5) After culturing, an α-glucosidase solution was prepared. Into a 2 L Erlenmeyer flask, 1 L of Czapek Dox's medium in which the carbon source is changed to glycerol is put, steam sterilized, pyrithiamine is added, the genetically modified strain is inoculated, and shaken at a temperature of 37 ° C. for 4 days. Culture was performed. Then, the cells were collected with Miracloth (manufactured by Merck Millipore), washed with distilled water, and the water was squeezed well.

  200 mL of 20 mM sodium acetate buffer solution (pH 5.5) was added to 100 g of the obtained bacterial cells, and disruption was repeated 5 times with Hiscotron (manufactured by Nisshin Medical Science Instrument Co., Ltd.) at 20,000 rpm for 5 seconds. The supernatant was recovered by centrifugation at 10,000 rpm for 20 minutes to obtain an α-glucosidase solution. The acquired enzyme analyzed the transfer thing at the time of making maltose a substrate by the method similar to the method performed by (Experimental example 1-3). As a result, α-glucosidase derived from Aspergillus niger CBS513.88 strain (Accession no. XP_001389510) was used as the reaction product obtained from Aspergillus niger ATCC10254 strain. Similar to the reaction product obtained, carbohydrates having α-1,2 bonds and α-1,3 bonds were observed.

(Experimental Example 1-7) Production of α-glucosidase derived from Aspergillus niger ATCC1015 strain and Aspergillus kawachii IFO4308 strain and analysis of transferred product
Using the NCBI database (http://www.ncbi.nlm.nih.gov/), a sequence presumed to be α-glucosidase having all five amino acid sequences of the above amino acid sequence groups (a) to (e) Searched for. As a result, an Aspergillus niger ATCC1015 strain (α-glucosidase Accession no .: EHA26885) and an Aspergillus kawachii IFO4308 strain (α-glucosidase Accession no .: GAA87366) are amino acid sequence groups ( It was found to have all five of a) to (e).

  Α-glucosidase derived from Aspergillus niger ATCC1015 strain (Accession no .: EHA26885, SEQ ID NO: 2) and α-glucosidase derived from Aspergillus kawachii IFO4308 strain (Accession no .: GAA87366, SEQ ID NO: 3) PCR was performed using a primer for amplifying from the start codon of DNA encoding each amino acid sequence to 300 bp downstream of the termination codon so as to include a terminator, and the obtained PCR product was used (Experimental example) A genetically modified strain was prepared in the same manner as the method for preparing a genetically modified strain performed in 1-5). CDNA was synthesized by reverse transcription using mRNA extracted from a gene recombinant strain obtained by introducing an α-glucosidase gene derived from ATCC1015 strain as a template. This cDNA was subjected to sequence analysis to determine the full-length sequence of the cDNA. Furthermore, the amino acid sequence of α-glucosidase was determined from the cDNA sequence. The determined amino acid sequence is shown in SEQ ID NO: 4. When this amino acid sequence was compared with that published as an amino acid sequence of α-glucosidase (Accession no .: EHA26885, SEQ ID NO: 2) derived from the Aspergillus niger ATCC1015 strain in the NCBI database, 76 residues The amino acid sequence was long.

  An α-glucosidase solution is obtained in the same manner as in (Experimental Example 1-6), and the transferred product when maltose is used as a substrate is analyzed in the same manner as in the analytical method performed in (Experimental Example 1-3). did. As a result, α-glucosidase derived from Aspergillus niger ATCC1015 (SEQ ID NO: 4) and α-glucosidase derived from Aspergillus kawachii IFO4308 (Accession no .: GAA87366) were obtained. In the reaction product, saccharides having α-1,2 bond and α-1,3 bond were recognized as in the reaction product obtained using α-glucosidase derived from Aspergillus niger ATCC10254 strain. It was.

(Experimental Example 1-8) Production of α-glucosidase derived from Aspergillus niger NBRC4066 strain and analysis of transferred product (Experimental Example 1-7), derived from Aspergillus niger ATCC1015 strain Extraction from Aspergillus genus strains using primers for amplifying from the start codon of DNA encoding the amino acid sequence of α-glucosidase (Accession no .: EHA26885) to 300 bp downstream of the stop codon so as to include a terminator PCR was performed using the genomic DNA as a template. The gene sequence was determined using the obtained PCR product (SEQ ID NO: 11). About the consignment strain in which amplification by PCR was observed, using the obtained PCR product, a genetically modified strain was prepared in the same manner as the method for preparing a genetically modified strain performed in (Experimental Example 1-5). An α-glucosidase solution was obtained in the same manner as in (Experimental Example 1-6), and the transferred product when maltose was used as a substrate in the same manner as the analytical method in (Experimental 1-3) Was analyzed. As a result, the reaction product of α-glucosidase derived from Aspergillus niger NBRC4066 strain contains α-1,2 bonds and α-glucosidase in the same manner as α-glucosidase derived from Aspergillus niger ATCC10254 strain. Carbohydrates having 1,3 bonds were observed. Moreover, cDNA was synthesized by reverse transcription reaction using as an template the mRNA extracted from the gene recombinant strain obtained by introducing the α-glucosidase gene derived from the Aspergillus nidu NBRC4066 strain. The cDNA was subjected to sequence analysis to determine the full-length cDNA sequence (SEQ ID NO: 12). Furthermore, the amino acid sequence of α-glucosidase was determined from the cDNA sequence. The determined amino acid sequence is shown in SEQ ID NO: 5. The amino acid sequence of α-glucosidase (SEQ ID NO: 5) of Aspergillus niger NBRC4066 strain had all five amino acid sequences (a) to (e).

(Experimental Example 1-9) Production of α-glucosidase derived from Aspergillus nidulans ATCC38163 strain and analysis of transferred product
Presumed to be α-glucosidase having one or more amino acid sequences selected from the above amino acid sequence groups (a) to (e) using NCBI database (http://www.ncbi.nlm.nih.gov/) The sequence to be searched was searched. As a result, the Aspergillus nidulans ATCC38163 strain (Accession no .: ABF50846, SEQ ID NO: 6 of α-glucosidase) had an amino acid sequence (e) and a sequence presumed to be α-glucosidase. . According to the method of (Experimental Example 1-5), a terminator is included from the start codon of DNA encoding the amino acid sequence of α-glucosidase (Accession no .: ABF50846) derived from Aspergillus nidulans ATCC38163 strain. A gene recombinant strain was prepared using a PCR product obtained by amplifying up to 300 bp downstream of the codon.

  An α-glucosidase solution was obtained according to the method of (Experimental Example 1-6), and the transferred product was analyzed using maltose as a substrate according to the method of (Experimental Example 1-3). As a result, α-glucosidase derived from Aspergillus niger ATCC10254 was added to the reaction product obtained using α-glucosidase derived from Aspergillus nidulans ATCC38163 (Accession no .: ABF50846). Similar to the reaction product obtained by use, carbohydrates having α-1,2 bonds and α-1,3 bonds were observed.

Experimental Example 1-10 Production of α-glucosidase from Aspergillus oryzae RIB40 strain, Aspergillus nidulans ATCC38163 strain, Aspergillus aculeatus ATCC16872 strain and analysis of transferred product
Α-glucosidase derived from Aspergillus niger CBS513.88 strain (Accession) described in (Experimental Example 1-5) using NCBI database (http://www.ncbi.nlm.nih.gov/) no .: XP_001389510) was searched for a sequence having high identity. Downstream of the stop codon so that it contains a terminator from the start codon of DNA encoding the sequence presumed to be α-glucosidase, which is highly identical to the amino acid sequence of α-glucosidase (Accession no .: XP_001389510) derived from CBS513.88 Using the PCR product amplified up to 300 bp, a genetically engineered strain was prepared in the same manner as in (Experimental Example 1-5).

  An α-glucosidase solution was obtained according to the method of (Experimental Example 1-6), and the transferred product was analyzed using maltose as a substrate in the same manner as the analytical method performed in (Experimental Example 1-3). As a result, α-glucosidase derived from Aspergillus oryzae RIB40 strain (Accession no .: XP — 001818060, SEQ ID NO: 7), α-glucosidase derived from Aspergillus nidulans ATCC38163 strain (Accession no .: ABF50883) , SEQ ID NO: 8), the reaction product obtained using α-glucosidase derived from Aspergillus niger ATCC 10254 strain, α-1,2 bond and α-1 , Carbohydrates with 3 bonds were observed.

  In addition, α-glucosidase derived from Aspergillus niger CBS513.88 strain described in (Experimental Example 1-5) using Aspergillus Genome Database (http://www.Aspergillusgenome.org/) (Accession no .: XP_001389510) was searched for sequences with high identity. Downstream of the stop codon so that it contains a terminator from the start codon of DNA encoding the sequence presumed to be α-glucosidase, which is highly identical to the amino acid sequence of α-glucosidase (Accession no .: XP_001389510) derived from CBS513.88 Using the PCR product amplified up to 300 bp, a genetically modified strain was prepared in the same manner as in (Experimental Example 1-5).

  An α-glucosidase solution was obtained by the same method as that used in (Experimental Example 1-6), and the transferred product when maltose was used as a substrate by the same method as that used in (Experimental Example 1-3) was used. analyzed. As a result, the reaction product obtained using the α-glucosidase derived from Aspergillus aculeatus ATCC16872 (Accession no .: Aacu16872_025147, SEQ ID NO: 9) includes α derived from Aspergillus niger ATCC10254. -Carbohydrates having α-1,2 bonds and α-1,3 bonds were observed as in the reaction product obtained using glucosidase.

(Experimental Example 1-11) Production of α-glucosidase derived from Aspergillus sojae NBRC4239 strain and analysis of transferred product
Genomic sequences derived from Aspergillus sojae were obtained using the NCBI database (http://www.ncbi.nlm.nih.gov/). An amino acid sequence deduced to be α-glucosidase from the genome sequence is defined, and α-glucosidase derived from Aspergillus niger CBS513.88 strain described in (Experimental Example 1-5) (Accession no .: XP_001389510) A sequence having high identity with the amino acid sequence of was extracted. Using a PCR product obtained by amplifying from the start codon of the DNA encoding the extracted amino acid sequence to 300 bp downstream of the stop codon so as to include a terminator, the gene was produced in the same manner as in (Experimental Example 1-5). A recombinant strain was produced.

  An α-glucosidase solution was obtained by the same method as that used in (Experimental Example 1-6), and the transferred product when maltose was used as a substrate by the same method as that used in (Experimental Example 1-3) was used. analyzed. As a result, the reaction product obtained using Aspergillus sojae NBRC4239 strain α-glucosidase (SEQ ID NO: 10) was obtained using Aspergillus niger ATCC10254 strain α-glucosidase. Similar to the reaction product, carbohydrates having α-1,2 bonds and α-1,3 bonds were observed.

(Experimental Example 1-12) Comparison of Amino Acid Sequences of α-Glucosidase that Generate Carbohydrates Having α-1,2 Bond and α-1,3 Bond (Experimental Example 1-5) to (Experimental Example 1-11) Α-glucosidase derived from Aspergillus niger, ATCC1015 strain (SEQ ID NO: 4), α-glucosidase derived from NBRC4066 strain (SEQ ID NO: 5), α-glucosidase derived from Aspergillus kawachii IFO4308 strain (Accession no. : GAA87366), α-glucosidase derived from Aspergillus oryzae RIB40 strain (Accession no .: XP — 001818060), α-glucosidase derived from Aspergillus sojae NBRC4239 strain (SEQ ID NO: 10), Aspergillus acuretus ( Aspergillus aculeatus) α-glucosidase derived from ATCC16872 strain (Accession no .: Aacu16872_025147) and Aspergillus nidulans (Asp ergillus nidulans) About the amino acid sequence of α-glucosidase (Accession no .: ABF50846, ABF50883) derived from ATCC38163 strain, using ClustalW (http://www.genome.jp/tools/clustalw/), Aspergillus nidu (Aspergillus nidulans) niger) When compared with the amino acid sequence of α-glucosidase (Accession no .: XP — 001389510) derived from strain CBS513.88, all showed 60% or more identity. Further, these α-glucosidases were found to have the following amino acid sequence groups 1 to 6 in common.
Sequence 1: FQSQY,
Sequence 2: LWIMNNEA,
Sequence 3: EYDTHNLYG,
Sequence 4: VGHWLGDN,
Sequence 5: GEPFL,
Sequence 6: FYDWYTG
(Experimental Example 1-13) Comparison with other α-glucosidase amino acid sequences Aspergillus niger CBS513 which mainly produces a saccharide having an α-1,6 bond whose degree of polymerization is one higher than that of the substrate. The amino acid sequence of .88 strain-derived α-glucosidase (Accession no .: XP_001402053) is the amino acid sequence of Aspergillus niger CBS 513.88 strain α-glucosidase (Accession no .: XP_001389510) and ClustalW (http: // When compared using www.genome.jp/tools/clustalw/), the identity was 36%. Moreover, it did not have the said amino acid sequence groups 1-6.

  In addition, the amino acid sequence of α-glucosidase (PCT / JP2014 / 077849) derived from Aspergillus sojae NBRC4239 strain that produces a carbohydrate having a continuous α-1,6 bond found by the present inventors, Aspergillus niger CBS 513.88 strain derived α-glucosidase (Accession no .: XP_001389510) amino acid sequence and identity using ClustalW (http://www.genome.jp/tools/clustalw/) Was 53%. Moreover, it did not have the amino acid sequence groups 1-6.

  The analysis results of the sequences of each α-glucosidase performed in the above experimental examples are shown in the following table.

Experimental Example 2: Preparation of various foods processed from starch-containing raw materials In this experimental example, the starch-containing raw material was processed using the food improver for food and drink according to the present invention, and the resulting saccharide was processed. This shows the characteristics of the food produced.

(Experimental example 2-1) Wheat starch 20 mL of buffer solution (12 mM phosphate buffer solution pH 6.0) which used 10 g of commercially available wheat starch, and added the enzyme so that it might become 0.2 U with respect to 1 g of raw material wheat starch. In addition, the mixture was stirred at 25 ° C. for 24 hours to carry out an enzyme reaction. After completion of the reaction, the reaction solution was filtered, and the filtrate was washed with 100 mL of water and dried to obtain wheat starch.

  As an enzyme, α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2), α-glucosidase derived from NBRC4066 strain obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and (Experimental Example 1-11) Wheat starch produced using the obtained NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) was designated as Example 1, Example 2, and Example 3, respectively. The wheat starch produced using transglucosidase L “Amano” (manufactured by Amano Enzyme Co., Ltd., hereinafter also referred to as TGL) was used as Comparative Example 1. Moreover, the wheat starch produced on the same conditions except not adding an enzyme was made into the reference example 1.

  The aging properties of the produced wheat starches of Examples 1 to 3, Comparative Example 1 and Reference Example 1 were evaluated using RVA4500 (manufactured by Perten Instruments). Each sample was suspended in water so as to have a solid content of 6% by mass, and processed under the gelatinization property measurement conditions shown in FIG. 3 to calculate a setback value (difference between final viscosity and minimum viscosity after gelatinization). . The results are shown in the table below.

  Compared to wheat starch prepared in the absence of enzyme (Reference Example 1), wheat starch prepared using the enzyme of the present invention (Examples 1, 2, and 3) and wheat starch prepared using TGL (Comparative Example 1) ) Was a small setback value. Moreover, when the setback value of the wheat starch produced using this enzyme (Examples 1, 2, 3) and the wheat starch produced using TGL (Comparative Example 1) was compared, wheat starch treated with this enzyme ( Examples 1, 2, and 3) showed smaller values. From this, it turns out that the starch which does not age easily can be obtained by using the foodstuff improving agent for food-drinks concerning this invention.

(Experimental example 2-2) Cooked rice Preparation of cooked rice was performed with reference to "Applied carbohydrate science Vol.4 p.93-102 2014". 70 μL of a buffer solution (12 mM phosphate buffer solution pH 6.0) added with an enzyme to 25 U per 1 g of raw raw rice was added to one commercially available raw rice grain (about 20 mg), and immersed for 2 hours at room temperature. Rice was stored at 10 ° C. for 1 month. Thereafter, rice was cooked using the GeneAmp PCR System 9700 (Applied Biosystems) under the conditions shown in the table below.

  As an enzyme, α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2), α-glucosidase derived from NBRC4066 strain obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and (Experimental Example 1-11) The cooked rice prepared using the obtained NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) was designated as Example 4, Example 5 and Example 6, respectively, and the cooked rice prepared using TGL was designated as Comparative Example 2. . Moreover, the cooked rice prepared on the same conditions except not adding an enzyme was made into the reference example 2. FIG.

  After cooking, the hardness of the cooked rice was measured. Hardness was measured using a texture analyzer TA.XT Plus (Stable Micro Systems, also referred to as TA), 90% compression under the conditions of a 20 mm diameter cylindrical plunger, plunger speed 2 mm / s, and load cell 5 kg. The stress (N) was measured and the value was regarded as the hardness of one grain of rice. Ten grains were measured for each sample, and the average value was determined. The results are shown in the table below.

  Compared with the cooked rice of Reference Example 2, the cooked rice of Examples 4 to 6 and Comparative Example 2 had a low hardness value (N) and was soft. Moreover, in the comparison of the cooked rice of Examples 4-6 and Comparative Example 2, Examples 4-6 were softer. In addition, the cooked rice of Examples 4 to 6 also had a higher flavor when eaten than Comparative Example 2 and Reference Example 2.

  From these results, it can be seen that by using the food improver for foods and drinks according to the present invention, it is possible to obtain cooked rice with a soft and preferable texture and to obtain cooked rice with improved flavor when eaten.

(Experimental Example 2-3) Washed 250 g of glutinous rice, added 160 mL of a buffer solution (12 mM phosphate buffer pH 6.0) to which 0.02 U of enzyme was added per 1 g of raw raw rice, and heated at room temperature for 30 minutes. Soaked. After that, the rice cake was produced at the rice cake course of the home bakery SD-BMS102 (Panasonic).

  As an enzyme, α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2), α-glucosidase derived from NBRC4066 strain obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and (Experimental Example 1-11) The rice cakes produced using the obtained NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) were designated as Example 7, Example 8 and Example 9, respectively, and the rice cake produced using TGL was designated as Comparative Example 3. . The rice cake prepared without adding the enzyme was used as Reference Example 3.

  The produced rice cakes were measured for 20 g each in a plastic petri dish, molded and then allowed to cool to room temperature, and then stored at 4 ° C. for 24 hours. For the measurement, TA was used, a cylinder plunger with a diameter of 40 mm, a plunger speed of 2 mm / s, and a load cell of 5 kg. N) was measured and the value was taken as the hardness. Ten points were measured for each sample, and the average value was determined. The results are shown in the table below.

  After standing to cool, compared to Reference Example 3, Examples 7, 8, 9 and Comparative Example 3 had a low hardness value (N) and were soft. In addition, in the comparison made by adding Examples 7, 8, and 9 and Comparative Example 3, the softer results were obtained when the enzyme of the present invention was added. Similarly, after storage at 4 ° C. for 24 hours, Examples 7, 8, and 9 were significantly softer than those prepared by adding Reference Example 3 and Comparative Example 3. Moreover, all the rice prepared using the enzyme of the present invention also improved the flavor when eaten.

  From these results, it can be seen that by using the food improver for foods and drinks according to the present invention, it is possible to obtain a soft texture immediately after the production, and that the softness can be maintained. Moreover, it turns out that the rice cake which the flavor at the time of eating improved can be obtained.

(Experimental example 2-4) Amazake To 200 g of dried rice bran, 800 mL of a buffer solution (12 mM phosphate buffer solution pH 6.0) added with an enzyme to give 1.5 U per 1 g of raw rice bran was added, and the mixture was stirred at 50 ° C. for 6 hours. Immersion was obtained to obtain amazake.

  As an enzyme, α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2), α-glucosidase derived from NBRC4066 strain obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and (Experimental Example 1-11) Amazake produced using the obtained NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) was designated as Example 10, Example 11 and Example 12, respectively, and Amazake produced using TGL was designated as Comparative Example 4. Amazake prepared under the same conditions except that no enzyme was added was used as Reference Example 4.

  The obtained amazake was collected by centrifugation and the water-soluble dietary fiber content in the liquid was determined by enzyme-HPLC method (AOAC 2001.03). The results are shown in the table below.

  The water-soluble dietary fiber content in the obtained amazake was 0.8% in Reference Example 4 and 0.9% in Comparative Example 4, but in Examples 10-12, it was 1.3-1.4. % Significantly increased. Moreover, the amazake produced by adding the enzyme of the present invention had improved mouthfeel. From this, it can be seen that by using the food improver for foods and drinks according to the present invention, amazake with an increased amount of water-soluble dietary fiber can be obtained and amazake with improved mouthfeel can be obtained.

(Experimental example 2-5) Preparation of sake Sake Furthermore, the test similar to (Experimental example 2-4) was done at low temperature supposing that an enzyme was added to the preparation process of sake. A mixture of the dried rice bran and the enzyme solution was held at 10 ° C. for 3 weeks so as to be 1.5 U per 1 g of raw rice bran. The results are shown in the table below.

  As an enzyme, α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2), α-glucosidase derived from NBRC4066 strain obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and (Experimental Example 1-11) The reaction solutions prepared using the obtained NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) were respectively Example 13, Example 14, and Example 15, and the reaction solutions prepared using TGL were Comparative Example 5. . Moreover, the reaction solution produced by the same method except not using an enzyme was made into the reference example 5. The results are shown in the table below.

  The water-soluble dietary fiber content in the obtained reaction solution was 0.5% in Reference Example 5 and Comparative Example 5, but 1.1 to 1.2% in Examples 13, 14, and 15. And increased significantly.

  Since dietary fiber is not assimilated by yeast, it is possible to obtain sake with an increased amount of water-soluble dietary fiber by adding the enzyme of the present invention to the preparation process.

(Experimental example 2-6) Bread The ingredients shown in the table below are added to the water to make 0.2 U per gram of strong flour, and the home bakery SD-BH105 (Panasonic) bread Bread bread was prepared at the baking course.

  ATCC10254 strain-derived α-glucosidase obtained in (Experimental Example 1-2), NBRC4066 strain-derived α-glucosidase obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and NBRC4239 obtained in (Experimental Example 1-11) Bread produced using strain-derived α-glucosidase (SEQ ID NO: 10) was designated as Example 16, Example 17, and Example 18, respectively, and bread produced using TGL was designated as Comparative Example 6. Moreover, the bread produced by the same method except not using an enzyme was made into the reference example 6.

  The prepared bread was allowed to cool to room temperature, stored at 25 ° C. for 1 day and 2 days, sliced to a thickness of 10 mm, and the crumb portion was cut into a 33 mm square to measure the hardness. For measurement, SUN RHEO METER COMPAC-100 II (manufactured by SUN SCIENTIFIC) is used to measure the stress (N) when compressed to a thickness of 5 mm under the conditions of a flat plunger with a diameter of 40 mm and a gantry speed of 60 mm / min. And the bread was hard. Ten points were measured for each sample, and the average value was determined. The results are shown in the table below.

  After storage for 1 day, Examples 16, 17, and 18 had lower hardness values (N) and were softer than Reference Example 6 and Comparative Example 6. In addition, even after storage for 2 days, the breads to which Examples 16, 17, and 18 were added remained soft. Moreover, the bread | pan produced by adding the enzyme of this invention also improved the flavor at the time of eating. From this, it can be seen that by using the food improver for foods and drinks according to the present invention, bread having a softness can be obtained, and bread having an improved flavor when eaten can be obtained.

(Experimental example 2-7) Udon Noodles with the composition shown in the table below are mixed with water to make 2U per gram of medium strength flour, and 2mm round with Noodle MakerHR2365 / 01 (manufactured by PHILIPS). Noodles were made using a noodle cap. As an enzyme, α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2), α-glucosidase derived from NBRC4066 strain obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and (Experimental Example 1-11) The noodles produced using the obtained NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) were designated as Example 19, Example 20, and Example 21, respectively, and the noodle produced using TGL was designated as Comparative Example 7. Moreover, the udon produced without adding an enzyme was used as Reference Example 7.

  The prepared udon was evaluated after being boiled and then tightened with cold water. The table below shows the number of people who sampled 10 subjects and answered that they had good hardness, elasticity, and stickiness.

  Compared to Reference Example 7, the udon produced using Examples 19, 20, and 21 and Comparative Example 7 were evaluated well for hardness, elasticity, and stickiness. Further, when Comparative Example 7 was compared, Examples 19, 20, and 21 were more preferable results for all of hardness, elasticity, and stickiness. Moreover, the udon produced by adding the enzyme of the present invention had improved flavor when eaten. From these results, by using the food improver for foods and drinks according to the present invention, it is possible to obtain a udon with a preferable hardness and elasticity, a preferable texture, and a flavor when eating. You can get the udon you made.

(Experimental example 2-8) Bread with barley For bread-making ingredients with the composition shown in the table below, the enzyme is dissolved in water to make 0.2 U per 1 g of strong flour, and added home bakery SD-BH105. A barley-containing bread was prepared. As an enzyme, α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2), α-glucosidase derived from NBRC4066 strain obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and (Experimental Example 1-11) The breads produced using the obtained NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) were designated as Example 22, Example 23, and Example 24, respectively, and the bread produced using TGL was designated as Comparative Example 8. . Moreover, the bread produced on the same conditions except not using an enzyme was made into the reference example 8.

  The prepared barley bread was allowed to cool to room temperature, stored at 25 ° C. for 2 days and 3 days, sliced into a thickness of 10 mm, and the crumb portion was cut into a 33 mm square to measure the hardness. For the measurement, SUN RHEO METER COMPAC-100 II was used to measure the stress (N) when compressed to a thickness of 5 mm under the conditions of a flat plunger with a diameter of 40 mm and a gantry speed of 60 mm / min. It was hard. Ten points were measured for each sample, and the average value was determined. The results are shown in the table below.

  After storage for 2 days, compared to Reference Example 8 and Comparative Example 8, the barley bread produced by adding Examples 22 to 24 had a low hardness value (N) and was soft. In addition, even after storage for 3 days, Examples 22 to 24 remained soft. Moreover, the barley-containing bread produced by adding the enzyme of the present invention also improved the flavor when eaten. From this, it can be seen that by using the food improver for food and drink according to the present invention, it is possible to obtain a barley-containing bread that maintains its softness.

(Experimental example 2-9) Beer and beer-like beverages To 200 g of malt, 800 mL of an enzyme solution added with an enzyme so as to be 1 U or 5 U per 1 g of malt was added, and 1.5 hours at 50 ° C. and 1 at 60 ° C. Heat treatment was performed for 5 minutes at 80 ° C. for 15 minutes. As the enzyme, α-glucosidase derived from NBRC4066 strain obtained in Example 25 and Example 26 (Experimental Example 1-8) using the α-glucosidase derived from ATCC10254 strain obtained in (Experimental Example 1-2) (sequence) Examples using No. 5) and those using the NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) obtained in Example 27 and Example 28 (Experimental Example 1-11) are referred to as Example 29 and Example 30. , TGL was used as Comparative Example 8 and Comparative Example 9. Further, Reference Example 8 was treated under the same conditions except that no enzyme was used as a control. After the heat treatment, the supernatant was collected by centrifugation, and the water-soluble dietary fiber content in the liquid was determined by enzyme-HPLC method (AOAC 2001.03). The results are shown in the table below.

  The water-soluble dietary fiber content in the obtained reaction solution was 1.3% in Reference Example 8, 1.5% in Comparative Example 8, and 1.7% in Comparative Example 9, but Example 25, In 27 and 29, it increased greatly to 2.6 to 2.8%. Furthermore, in Examples 26, 28, and 30 to which 5 U of enzyme was added, the number was further significantly increased to 4.0 to 4.3%. From this, it is understood that a malt saccharified solution with an increased amount of water-soluble dietary fiber can be obtained by adding this enzyme.

  In the production of beer, there is a fermentation process using brewer's yeast after the saccharification process, which is the aforementioned process. Since dietary fiber is not assimilated by brewer's yeast, beer with an increased amount of water-soluble dietary fiber can be obtained by adding the enzyme of the present invention. In addition, since the malt saccharified solution prepared by adding the enzyme of the present invention has reduced miscellaneous taste derived from millet grains, by adding the enzyme of the present invention, it is possible to obtain a pleasant beer with reduced miscellaneous taste. Can do.

  Next, barley was mixed with the raw material malt and the same test was conducted. Add 800 mL of enzyme solution with enzyme added to 1 U per 1 g of malt and barley combined with 20 g of malt and 180 g of barley, add 1 hour at 50 ° C., 1 hour at 60 ° C., then 80 ° C. Heat treatment for 10 minutes was performed. The results are shown in the table below. ATCC10254 strain-derived α-glucosidase obtained in (Experimental Example 1-2), NBRC4066 strain-derived α-glucosidase obtained in (Experimental Example 1-8) (SEQ ID NO: 5), and NBRC4239 obtained in (Experimental Example 1-11) The reaction solutions prepared using strain-derived α-glucosidase (SEQ ID NO: 10) were designated as Example 31, Example 32, and Example 33, respectively, and the reaction solution prepared using TGL was designated as Comparative Example 10. Moreover, the reaction solution produced on the same conditions except not using an enzyme was made into the reference example 9. After the heat treatment, the supernatant was collected by centrifugation, and the water-soluble dietary fiber content in the liquid was determined by enzyme-HPLC method (AOAC 2001.03). The results are shown in the table below.

  The water-soluble dietary fiber content in the obtained reaction solution was 1.2% in Reference Example 9 and 1.5% in Comparative Example 10, but in Examples 31, 32, and 33, 2.2% to It increased significantly to 2.4%. From these results, it can be seen that by using the food improver for food and drink according to the present invention, the amount of water-soluble dietary fiber can be increased regardless of the malt blending ratio.

(Experimental example 2-10) Mashed potatoes One potato was peeled and cut into a thickness of 1.5 cm, and a buffer solution (12 mM phosphate buffer pH 6.0) to which 2 U / g of potato was added was added. 180 mL was added and immersed at room temperature for 2 hours. After that, the potatoes were boiled, drained and crushed with a masher to make mashed potatoes. Mashed potatoes prepared by adding ATCC10254 strain-derived α-glucosidase, NBRC4066 strain-derived α-glucosidase (SEQ ID NO: 5), and NBRC4239 strain-derived α-glucosidase (SEQ ID NO: 10) were obtained in Example 34, Example 35 and Example, respectively. The mashed potato prepared by adding TGL to 36 was designated as Comparative Example 11. A mashed potato prepared without adding an enzyme was used as Reference Example 10.

  The produced mashed potato was evaluated immediately after production and after being stored at 25 ° C. for 2 hours. The results are shown in the table below. The evaluation was made by the number of respondents who had 10 test subjects and answered that the moist sensation and softness were good for mashed potatoes prepared without the addition of enzymes.

  In the mashed potatoes immediately after production, Examples 34 to 36 and Comparative Example 11 were better evaluated for moist feeling and softness than Reference Example 10. In addition, in Examples 34 to 36, the flavor when eating was improved as compared with Reference Example 10 and Comparative Example 11.

  In the mashed potato after storage for 2 hours, as compared with Comparative Example 11, Examples 34 to 36 maintained a good texture, and in particular, the softness was more favorable. Moreover, the flavor at the time of eating Examples 34-36 compared with the reference example 10 and the comparative example 11 was improving. From these results, it can be seen that by using the food improver for foods and drinks according to the present invention, the texture and flavor immediately after production are good, and further, mashed potatoes that maintain a good texture and flavor can be obtained. .

(Experimental example 2-11) The foodstuff which added the enzyme treatment starch The starch containing foodstuff was manufactured using the enzyme treatment starch produced in (Experimental example 2-1). Specifically, the blended sausages shown in the table below were produced by a conventional method as processed meat products.

  In addition, as a marine processed product, straw was prepared by a conventional method with the composition shown in the table below.

  The obtained sausage had a good flavor with reduced animal odor. In addition, the salmon had a good flavor with suppressed fishy odor. From this, it is understood that sausage and koji with good flavor can be obtained by using the food improver for food and drink according to the present invention. In the production of sausage and koji, starch can be enzymatically treated by adding the food improver for food and drink of the present invention during the production process of the starch-containing food.

Claims (21)

A food improver for foods and drinks manufactured by processing starch-containing raw materials, including α-glucosidase,
The α-glucosidase acts on a saccharide selected from the group consisting of an α-type oligosaccharide and an α-type polysaccharide, and a saccharide having an α-1,2 bond and a saccharide having an α-1,3 bond. The food improver as described above, which produces quality.   The food improver according to claim 1, which is for improving the quality of processed rice products.   The food improver according to claim 1, which is for improving the quality of processed wheat products.   The food improver according to claim 1, which is for improving the quality of processed barley products.   The food improver according to claim 1, which is for improving the quality of processed potato products. The amino acid sequence encoding the α-glucosidase is
The food improving agent according to any one of claims 1 to 5, which has 60% or more identity with the amino acid sequence described in any one of SEQ ID NOs: 1 to 10. The amino acid sequence encoding the α-glucosidase is
Sequence 1: FQSQY,
Sequence 2: LWIMNNEA,
Sequence 3: EYDTHNLYG,
Sequence 4: VGHWLGDN,
Sequence 5: GEPFL and
Sequence 6: FYDWYTG,
The food improver according to any one of claims 1 to 6, comprising any one or more sequences selected from the group consisting of:   The food improver according to any one of claims 1 to 7, wherein the α-glucosidase is an α-glucosidase derived from an Aspergillus genus. A method for improving a food or drink produced by processing a starch-containing raw material, comprising causing α-glucosidase to act on starch,
The α-glucosidase acts on a saccharide selected from the group consisting of an α-type oligosaccharide and an α-type polysaccharide, and a saccharide having an α-1,2 bond and a saccharide having an α-1,3 bond. The above method, which produces quality.   The method according to claim 9, which is for improving the quality of processed rice products.   10. A method according to claim 9 for improving the quality of wheat processing.   The method according to claim 9, which is for improving the quality of processed barley products.   The method according to claim 9, wherein the method is for improving the quality of a processed potato product. The amino acid sequence encoding the α-glucosidase is
The method according to any one of claims 9 to 13, which has 60% or more identity with the amino acid sequence described in any one of SEQ ID NOs: 1 to 10. The amino acid sequence encoding the α-glucosidase is
Sequence 1: FQSQY,
Sequence 2: LWIMNNEA,
Sequence 3: EYDTHNLYG,
Sequence 4: VGHWLGDN,
Sequence 5: GEPFL and
Sequence 6: FYDWYTG,
The method according to any one of claims 9 to 14, comprising any one or more sequences selected from the group consisting of:   The method according to any one of claims 9 to 15, wherein the α-glucosidase is an α-glucosidase derived from an Aspergillus genus. Treating starch with α-glucosidase;
Adding processed starch to processed foods,
A method for improving the quality of processed foods, comprising:
The α-glucosidase acts on a saccharide selected from the group consisting of an α-type oligosaccharide and an α-type polysaccharide to produce a saccharide having an α1,2 bond and a saccharide having an α-1,3 bond. The above method.   The method according to claim 17, wherein the method is for improving the quality of processed meat products or processed fish products. The amino acid sequence encoding the α-glucosidase is
The method according to claim 17 or 18, which has 60% or more identity with the amino acid sequence described in any one of SEQ ID NOs: 1 to 10. The amino acid sequence encoding the α-glucosidase is
Sequence 1: FQSQY,
Sequence 2: LWIMNNEA,
Sequence 3: EYDTHNLYG,
Sequence 4: VGHWLGDN,
Sequence 5: GEPFL and
Sequence 6: FYDWYTG,
The method according to any one of claims 17 to 19, comprising any one or more sequences selected from the group consisting of:   The method according to any one of claims 17 to 20, wherein the α-glucosidase is an α-glucosidase derived from an Aspergillus genus.