Milk substitute composition containing yeast extract fungal residue

Abstract

Provided is a milk substitute composition for protein supplementation, which reduces characteristic flavors (taste, sourness) originating from yeast materials.　More specifically, provided are: a milk substitute composition containing a yeast extract fungal residue or a cell-wall lysing enzyme decomposition product of said residue, and characterized in that the total content of free amino acids (especially glutamic acid) in the residue or the decomposition product is less than a prescribed amount; and milk substitute food and drinks containing the composition. Since the characteristic flavors of the yeast are remarkably reduced, the composition of the present invention can be included in various foods and drinks as a milk substitute composition, at concentrations higher than that of conventional products.

Description

Dairy replacer composition containing yeast extract cell residue

[0001] The present invention relates to a milk substitute composition containing yeast extract cell residue or a cell wall-lytic enzyme hydrolysate thereof, characterized in that the total amount of free amino acids (particularly glutamic acid) contained in the residue or hydrolysate is less than a predetermined amount, and to a milk substitute food or beverage containing the composition.

[0002] In recent years, due to the increasing demand for low-fat or fat-free foods due to dietary and health-conscious diets, or the increasing demand for vegan diets, in order to avoid milk-derived allergens, foods using plant-derived dairy substitutes such as oats, soybeans, and almonds instead of dairy ingredients have been attracting more attention. However, these plant-derived dairy substitutes are usually more expensive than cow's milk and are known to contain allergens.

[0003] In addition to such plant-derived milk substitutes, milk substitutes derived from yeast materials have also been reported. For example, the present applicant has reported the use of a yeast cell wall hydrolysate-containing composition, which contains a cell wall-lytic enzyme hydrolysate of the residue (yeast extract cell residue) after yeast extract production, as a milk substitute (see, for example, Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2022-135934

[0005] However, dairy substitutes derived from yeast materials have characteristic flavors (umami and sourness), and therefore, when used at a concentration of about 5% for the purpose of protein supplementation, the strong flavor makes them unsuitable for direct consumption.

[0006] As a result of extensive research to solve the above problems, the inventors have discovered that in a milk substitute composition containing yeast extract cell residue or its cell wall-lytic enzyme hydrolysate, by reducing the total amount of free amino acids (particularly glutamic acid) and acid components (particularly phosphoric acid) contained in the residue or hydrolysate to less than a predetermined amount, the characteristic flavour can be reduced and the milk substitute composition can be directly consumed, thereby completing the present invention.

[0007] Thus, the gist of the present invention is as follows. [1] A milk replacer composition containing a yeast extract cell residue, wherein the total amount of free glutamic acid contained in the residue is less than 0.5% by mass, based on the dry mass of the residue. [2] The composition according to [1], wherein the total amount of free amino acids contained in the residue is less than 1% by mass, based on the dry mass of the residue. [3] The composition according to [1] or [2], wherein the total amount of phosphoric acid contained in the residue is less than 0.1% by mass, based on the dry mass of the residue. [4] The composition according to any one of [1] to [3], wherein the residue is a water-insoluble fraction obtained after hot water extraction of yeast. [5] The composition according to any one of [1] to [4], wherein the residue contains less than 5% by mass of soluble solids, based on the dry mass of the residue. [6] A milk replacer composition comprising a cell wall-lytic enzyme hydrolysate of yeast extract cell residue, wherein the total amount of free glutamic acid contained in the hydrolysate is less than 0.4% by mass, based on the dry mass of the hydrolysate. [7] The composition according to [6], wherein the total amount of free amino acids contained in the hydrolysate is less than 1% by mass, based on the dry mass of the hydrolysate. [8] The composition according to [6] or [7], wherein the total amount of phosphoric acid contained in the hydrolysate is less than 0.20% by mass, based on the dry mass of the hydrolysate. [9] The composition according to any one of [6] to [8], wherein the milk replacer composition comprises a cell wall-lytic enzyme hydrolysate of yeast extract cell residue, wherein the soluble solids content of the residue is less than 5% by mass, based on the dry mass of the residue.

[10] The composition according to any one of [6] to [9], wherein the degradation product is obtained by a method comprising the following steps: (a) treating yeast extract cell residue with a cell wall-lytic enzyme at 40 to 60°C for 1 to 24 hours, and (b) recovering the treated product obtained in (a).

[11] The composition according to any one of [6] to

[10] , wherein the cell wall-lytic enzyme is a glucanase.

[12] The composition according to any one of [6] to

[11] , wherein the cell wall-lytic enzyme is a glucanase having β-1,3, β-1,4, and / or β-1,6 activity.

[13] The composition according to any one of [6] to

[12] , wherein the cell wall-lytic enzyme is a glucanase derived from Streptomyces.

[14] The composition according to any one of [6] to

[13] , wherein the cell wall-lytic enzyme is a glucanase without protease activity.

[15] A milk substitute food or beverage comprising the composition according to any one of [1] to

[14] .

[16] The milk substitute food or beverage according to

[15] , further comprising 0.1 to 30 mass% of an oil or fat.

[17] A method for improving the flavor of a milk substitute composition containing a yeast extract cell cell residue, the method comprising reducing the total amount of free glutamic acid contained in the residue to less than 0.5 mass% based on the dry mass of the residue.

[18] A method for improving the flavor of a milk substitute composition containing a cell wall-lytic enzyme hydrolysate of yeast extract cell cell residue, the method comprising reducing the total amount of free glutamic acid contained in the hydrolysate to less than 0.4 mass% based on the dry mass of the hydrolysate.

[19] Use of yeast extract cell residue as a milk replacer composition, wherein the total amount of free glutamic acid contained in the residue is less than 0.5% by mass, based on the dry mass of the residue.

[20] Use of a cell wall-lytic enzyme hydrolyzed product of yeast extract cell residue as a milk replacer composition, wherein the total amount of free glutamic acid contained in the hydrolyzed product is less than 0.4% by mass, based on the dry mass of the hydrolyzed product.

[0008] According to the present invention, a milk replacer composition can be provided using inexpensive and easily available yeast extract cell residue as a raw material. The composition of the present invention significantly reduces the characteristic flavor (particularly umami and sourness) unique to yeast by controlling the total amount of free amino acids (particularly glutamic acid) and acid components (particularly phosphoric acid) contained in the yeast extract cell residue or its cell wall-lytic enzyme hydrolysate to less than a specific amount, allowing the composition to be incorporated into various foods and beverages as a milk replacer composition at higher concentrations than conventional products. Therefore, the composition of the present invention makes it easier to ingest yeast-derived proteins, dietary fiber, and other nutrients.

[0009] 1 is a radar chart showing the results (average values) of sensory evaluations by five expert panelists for formulations 1 and 2 in Test Example 1. FIG. 2 is a radar chart showing the results (average values) of sensory evaluations by five expert panelists for formulations 3 and 4 in Test Example 2. FIG. 3 is a radar chart showing the results (average values) of sensory evaluations by five expert panelists for formulations 5 and 6 in Test Example 2. FIG. 4 is a radar chart showing the results (average values) of sensory evaluations by five expert panelists for formulations 7 and 8 in Test Example 2. FIG. 5 is a radar chart showing the results (average values) of sensory evaluations by five expert panelists for formulations 9 and 10 in Test Example 2. FIG. 6 is a radar chart showing the results (average values) of sensory evaluations by five expert panelists for formulations 11 and 12 in Test Example 2. FIG. 7 is a radar chart showing the results (average values) of sensory evaluations by five expert panelists for yeast extract cell residues (compositions of Comparative Examples 1, 3-4, and Examples 1 and 3) in Test Example 5. 1 is a radar chart showing the results (average values) of sensory evaluation by five expert panelists for cell wall-lytic enzyme decomposition products (compositions of Comparative Examples 2, 5-6, and Examples 2 and 4) in Test Example 5.

[0010] One embodiment of the present invention provides a milk replacer composition comprising a yeast extract cell residue, wherein the total amount of free glutamic acid contained in the residue is preferably less than 0.5% by mass, based on the dry mass of the residue.

[0011] In the present invention, the term "milk substitute composition" refers to a composition that can be used in place of milk (typically cow's milk) consumed by humans. Milk consumed by humans is a cloudy liquid secreted from mammalian mammary glands that contains nutrients such as water, protein, lipids, carbohydrates, vitamins, and minerals, and has a unique milky flavor. A milk substitute composition refers to a liquid consumed that possesses one or more of these characteristics. Milk substitute compositions are generally produced from plant materials such as soybeans, almonds, oats, rice, and coconut, and contain plant-derived proteins and lipids, as well as dietary fiber that is rarely found in milk. These plant-based compositions may be used alone or in combination, or may be mixed with animal-derived milk. The milk substitute composition of the present invention can also be used in place of milk substitute compositions produced from such known plant materials.

[0012] The term "yeast extract cell residue" as used herein includes yeast cell walls and is not particularly limited as long as it is the residue (insoluble fraction) of yeast cells obtained after subjecting yeast to an extraction process. Specifically, it refers to yeast cells that are generated as a residue after subjecting yeast to a known extraction process such as autolysis (protease treatment), hot water treatment, acid treatment, alkali treatment, and / or mechanical disruption, and removing the supernatant (water-soluble fraction (yeast extract)) separated by centrifugation or the like. The yeast extract cell residue is preferably the residue (water-insoluble fraction) of yeast cells after hot water extraction of yeast. The yeast extract cell residue (water-insoluble fraction) of the present invention preferably has a soluble solid content of less than 5% by mass relative to its dry mass. The solubility of the soluble solids refers to their solubility in water, and the soluble solids are calculated as the proportion (mass%) of the dry mass of the yeast extract cell residue. The content of soluble solids contained in the yeast extract cell residue according to the present invention can be measured, for example, according to the method described in Test Example 4 below. Furthermore, as used herein, the "dry mass of yeast extract cell residue" refers to the mass of the yeast extract cell residue after drying the yeast extract cell residue by a known method. There are no particular limitations on the drying method, and known drying methods can be used, such as atmospheric heat drying, vacuum drying, spray drying, and freeze drying. For example, the soluble solids content can be determined by drying a sample at 105°C for 5 hours in an atmospheric heat dryer and then weighing the residue.

[0013] Yeast extract cell residue is composed of proteins, lipids, ash, dietary fiber, and the like. The protein content is, for example, 20% to 60% by mass based on the dry mass of the yeast extract cell residue. The lipid content is, for example, 1% to 10% by mass based on the dry mass of the yeast extract cell residue. The ash content is, for example, 0% to 10% by mass based on the dry mass of the yeast extract cell residue. The dietary fiber content is, for example, 10% to 60% by mass based on the dry mass of the yeast extract cell residue. In addition to general nutritional components, yeast extract cell residue also contains components such as β-glucan and α-mannan, which have been reported to have physiological functions. β-glucan is a polysaccharide formed by the polymerization of D-glucose via β-1,3 and β-1,6 bonds, and is classified as dietary fiber because it is a resistant component in food that cannot be digested by human digestive enzymes. α-Mannan is a polysaccharide formed by the polymerization of D-mannose via α-1,6, α-1,2, or α-1,3 bonds. It is classified as dietary fiber because it is an indigestible food component that cannot be digested by human digestive enzymes. The β-glucan content is, for example, 10% to 40% by mass relative to the dry mass of the yeast extract cell residue. The α-mannan content is, for example, 10% to 40% by mass relative to the dry mass of the yeast extract cell residue. The content of each component can be measured by known analytical methods. The protein content can be determined, for example, by measuring the nitrogen content using the Kjeldahl method and multiplying the nitrogen content by a conversion factor of 6.25. The lipid content can be quantified, for example, by acid hydrolysis. The ash content can be quantified by direct ashing. The dietary fiber content can be quantified, for example, by the Prosky method (enzyme-gravimetric method) or high-performance liquid chromatography (enzyme-HPLC method). The α-mannan content can be measured, for example, by quantifying the amount of mannose produced by hydrolyzing mannan, and the β-glucan content can be measured, for example, using a (1-3), (1-4)-β-glucan measurement kit (Megazyme).

[0014] If the total amount of free amino acids (particularly glutamic acid) and acid components in the yeast cell residue (water-insoluble fraction) obtained in this manner is equal to or greater than the predetermined amount described below, appropriate purification and washing procedures can be carried out as necessary to obtain the yeast extract cell residue of the present invention, in which the total amount of free amino acids (particularly glutamic acid) and acid components is less than the predetermined amount described below. Examples of such purification and washing procedures include repeated extraction and separation procedures and increasing the amount of washing water.

[0015] The yeast is not particularly limited as long as it is applicable to the food industry, and examples thereof include yeast for beer production, yeast for bread production, and yeast for sake production. Alternatively, the yeast is not limited to these, and examples thereof include those belonging to genera such as Saccharomyces, Saccharomycodes, Rhodotorula, Endomycopsis, Nematospora, Brettanomyces, Candida, and Torulopsis. Of these, Saccharomyces cerevisiae, Saccharomyces pastorianus, and Saccharomyces bayanus are preferred. These may be used alone or in combination of two or more types.

[0016] The yeast extract cell residue of the present invention is characterized in that the total amount of free glutamic acid has been reduced to less than a predetermined amount. Specifically, the total amount of free glutamic acid contained in the yeast extract cell residue of the present invention is less than 0.5% by mass, preferably less than 0.4% by mass, and more preferably less than 0.3% by mass, based on the dry mass of the residue. Glutamic acid is an acidic amino acid that contributes to a sour taste, and its sodium salt is known to have a strong umami flavor. The present inventors have found that by controlling the glutamic acid content in the yeast extract cell residue to less than 0.5% by mass, the characteristic flavor unique to yeast is significantly reduced.

[0017] Furthermore, the yeast extract cell residue according to the present invention is preferably one in which not only the amount of free glutamic acid but also the total amount of free amino acids has been reduced to less than a predetermined amount. Specifically, the total amount of free amino acids contained in the yeast extract cell residue according to the present invention is preferably less than 1% by mass, more preferably less than 0.8% by mass, and even more preferably less than 0.5% by mass, based on the dry mass of the residue.

[0018] In the present invention, the term "total amount of free amino acids" refers to the sum of the amounts of histidine (His), asparagine (Asn), serine (Ser), glutamine (Gln), arginine (Arg), glycine (Gly), aspartic acid (Asp), glutamic acid (Glu), threonine (Thr), alanine (Ala), γ-aminobutyric acid (GABA), proline (Pro), cysteine ​​(Cys), lysine (Lys), tyrosine (Tyr), methionine (Met), valine (Val), isoleucine (Ile), leucine (Leu), phenylalanine (Phe), and tryptophan (Trp), as measured by UPLC analysis (labeling method) in the Examples described below. The free amino acids may be in the L-, D-, or DL-form, but are preferably in the L-form.

[0019] Amino acids are also known to contribute to bitterness, sweetness, and the like. Therefore, the yeast extract cell residue of the present invention preferably has the total amount of free amino acids known to impart bitterness and / or sweetness reduced to less than a predetermined amount. Therefore, for example, in the yeast extract cell residue of the present invention, the total amount of free amino acids known to impart bitterness, phenylalanine, tyrosine, arginine, isoleucine, leucine, valine, methionine, and lysine, is preferably less than 0.07% by mass, more preferably less than 0.05% by mass, and even more preferably less than 0.03% by mass, based on the dry mass of the residue. Furthermore, the total amount of free amino acids known to impart sweetness, alanine and proline, is preferably less than 0.2% by mass, more preferably less than 0.1% by mass, and even more preferably less than 0.05% by mass, based on the dry mass of the residue. By controlling the total amount of free amino acids in the yeast extract cell residue according to the present invention, as well as the total amount of free amino acids known to impart bitterness or sweetness, it is expected that the characteristic flavor specific to yeast can be further reduced.

[0020] The yeast extract cell residue of the present invention is also preferably one in which the total amount of acid components has been reduced to less than a predetermined amount. Specifically, the acid components contained in the yeast extract cell residue of the present invention are typically phosphoric acid and citric acid, and the phosphoric acid content is preferably less than 0.1% by mass, more preferably less than 0.05% by mass, based on the dry mass of the residue. Furthermore, the citric acid content is preferably less than 0.03% by mass, more preferably less than 0.02% by mass, based on the dry mass of the residue. By controlling the total amount of acid components in the yeast extract cell residue of the present invention, it is expected that the characteristic flavor unique to yeast can be further reduced.

[0021] The milk replacer composition of the present invention containing yeast extract cell residue may be in the form of a cloudy liquid or paste containing yeast extract cell residue at an appropriate concentration, for example, about 0.001 to about 30% by mass, preferably about 5 to about 20% by mass, in a suitable medium (preferably water). Alternatively, the milk replacer composition of the present invention may be the yeast extract cell residue (water-insoluble fraction) itself, or may be in the form of a powder, preferably with a soluble solids content of less than 5% by mass. By using the composition of the present invention, nutrients such as yeast-derived protein and dietary fiber can be ingested.

[0022] Another embodiment of the present invention provides a milk replacer composition containing a cell wall-lytic enzyme hydrolysate of yeast extract cell residue, preferably a composition in which the total amount of free glutamic acid contained in the hydrolysate is less than 0.4% by mass relative to the dry mass of the hydrolysate. The terms "yeast extract cell residue" and "milk replacer composition" are as defined above. As used herein, the "dry mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell residue" refers to the mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell residue after drying the cell wall-lytic enzyme hydrolysate of yeast extract cell residue using a known method. The drying method is not particularly limited, and known drying methods can be used, including atmospheric heat drying, vacuum drying, spray drying, and freeze drying. For example, the dry mass can be obtained by drying a sample at 105°C for 5 hours in an atmospheric heat dryer and then weighing the residue.

[0023] The cell wall-lytic enzyme digestion product according to the present invention is characterized in that the total amount of free glutamic acid contained in the cell wall-lytic enzyme digestion product according to the present invention is reduced to less than a predetermined amount, specifically, the total amount of free glutamic acid contained in the cell wall-lytic enzyme digestion product according to the present invention is less than 0.4% by mass, preferably less than 0.3% by mass, and more preferably less than 0.1% by mass, based on the dry mass of the digestion product.

[0024] Furthermore, the cell wall-lytic enzyme decomposition product according to the present invention is preferably one in which not only the amount of free glutamic acid but also the total amount of free amino acids has been reduced to less than a predetermined amount. Specifically, the total amount of free amino acids contained in the cell wall-lytic enzyme decomposition product according to the present invention is preferably less than 1% by mass, more preferably less than 0.5% by mass, and even more preferably less than 0.3% by mass, based on the dry mass of the decomposition product.

[0025] In addition, in the cell wall-lytic enzyme hydrolysate of the present invention, the total amount of free amino acids known to impart bitterness, phenylalanine, tyrosine, arginine, isoleucine, leucine, valine, methionine, and lysine, is preferably less than 0.1% by mass, more preferably less than 0.07% by mass, and even more preferably less than 0.05% by mass, based on the dry mass of the hydrolysate. Furthermore, the total amount of free amino acids known to impart sweetness, alanine and proline, is preferably less than 0.2% by mass, more preferably less than 0.1% by mass, and even more preferably less than 0.05% by mass, based on the dry mass of the hydrolysate. By controlling the total amount of free amino acids and the total amount of free amino acids known to impart bitterness or sweetness, the characteristic flavor specific to yeast can be expected to be further reduced in the cell wall-lytic enzyme hydrolysate of the present invention.

[0026] The cell wall-lytic enzyme hydrolysate of the present invention preferably has a total acid component content reduced to less than a predetermined amount. Specifically, the acid components contained in the cell wall-lytic enzyme hydrolysate of the present invention are typically phosphoric acid and citric acid, and the phosphoric acid content is preferably less than 0.20 mass%, more preferably less than 0.15 mass%, and even more preferably less than 0.10 mass%, based on the dry mass of the hydrolysate. Furthermore, the citric acid content is preferably less than 0.02 mass%, more preferably less than 0.01 mass%, based on the dry mass of the hydrolysate. By controlling the total amount of acid components in the cell wall-lytic enzyme hydrolysate of the present invention, further reduction of the characteristic flavor peculiar to yeast can be expected.

[0027] As used herein, the term "cell wall-lytic enzyme" refers to an enzyme or combination of enzymes capable of partially or completely degrading yeast cell walls. Cell wall-lytic enzymes preferably have endoactivity, and more preferably have only endoactivity. Cell wall-lytic enzymes preferably have low, almost no, or no protease activity (i.e., no protease activity). Alternatively, when using a cell wall-lytic enzyme with protease activity, or when an enzyme with protease activity is coexisting, it is preferable to use it under conditions (e.g., pH, temperature, etc.) that suppress the protease activity.

[0028] The cell wall lytic enzyme may be, for example, a naturally occurring enzyme, a commercially available enzyme, or an enzyme obtained by a method using genetic engineering or the like.

[0029] Examples of cell wall lytic enzymes include, but are not limited to, glucanases, mannanases, etc. Glucanases (preferably glucanases having endoactivity (preferably only endoactivity) and / or no protease activity) are, for example, glucanases having β-1,3, β-1,4, and / or β-1,6 activity, preferably glucanases derived from the genus Streptomyces or Talaromyces, more preferably glucanases derived from the genus Streptomyces, even more preferably glucanases derived from Streptomyces and having β-1,3, β-1,4, and / or β-1,6 activity, and even more preferably glucanases derived from Streptomyces and having β-1,3, β-1,4, and / or β-1,6 activity. and endo activity (preferably only endo activity), and even more preferably, a glucanase derived from Streptomyces that has β-1,3, β-1,4, and / or β-1,6 activity, endo activity, and no protease activity (e.g., Denatzyme GEL-L1 / R manufactured by Nagasevita Co., Ltd.), and even more preferably, a glucanase derived from Streptomyces that has β-1,3, β-1,4, and / or β-1,6 activity, endo activity, and no protease activity.

[0030] In one embodiment of the present invention, the cell wall lytic enzyme is a glucanase.

[0031] In one embodiment of the invention, the cell wall lytic enzyme is a glucanase having β-1,3, β-1,4, and / or β-1,6 activity.

[0032] In one embodiment of the present invention, the cell wall lytic enzyme is a glucanase derived from Streptomyces.

[0033] In one preferred embodiment of the present invention, the cell wall lytic enzyme is a glucanase derived from Streptomyces and having β-1,3, β-1,4, and / or β-1,6 activity.

[0034] In one embodiment of the present invention, the cell wall lytic enzyme is a glucanase having endoactivity (preferably having only endoactivity).

[0035] In a preferred embodiment of the present invention, the cell wall-lytic enzyme is a glucanase derived from Streptomyces and having β-1,3, β-1,4, and / or β-1,6 activity and endo activity (preferably, having only endo activity).

[0036] In one embodiment of the present invention, the cell wall-lytic enzyme is a glucanase that does not have protease activity.

[0037] In a preferred embodiment of the present invention, the cell wall-lytic enzyme is a glucanase derived from Streptomyces, having β-1,3, β-1,4, and / or β-1,6 activity, endo activity (preferably, only endo activity), and no protease activity.

[0038] As used herein, the term "cell wall-lytic enzyme hydrolysate" refers to a substance obtained by hydrolyzing yeast extract cell residue with a cell wall-lytic enzyme, specifically, a substance obtained by hydrolyzing yeast cell walls contained in the yeast extract cell residue with a cell wall-lytic enzyme.

[0039] The cell wall-lytic enzyme hydrolysate of yeast extract cell body residue is composed of proteins, lipids, ash, dietary fiber, etc. The protein content is, for example, 20% to 60% by mass, based on the dry mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell body residue. The lipid content is, for example, 1% to 10% by mass, based on the dry mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell body residue. The ash content is, for example, 0% to 10% by mass, based on the dry mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell body residue. The dietary fiber content is, for example, 10% to 60% by mass, based on the dry mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell body residue. In addition to general nutritional components, the cell wall-lytic enzyme hydrolysate of yeast extract cell body residue also contains components such as β-glucan and α-mannan, which have been reported to have physiological functions. β-Glucan is a polysaccharide in which D-glucose is polymerized via β-1,3 and β-1,6 bonds, and is classified as dietary fiber because it is an indigestible food component that is not digested by human digestive enzymes. α-Mannan is a polysaccharide in which D-mannose is polymerized via α-1,6, α-1,2, or α-1,3 bonds, and is classified as dietary fiber because it is an indigestible food component that is not digested by human digestive enzymes. The β-glucan content varies depending on the exoactivity of glucanases contained in cell wall-lytic enzymes, but is typically 0% to 40% by mass relative to the dry mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell body residue. The α-mannan content is typically 10% to 40% by mass relative to the dry mass of the cell wall-lytic enzyme hydrolysate of yeast extract cell body residue. The content of each component can be measured by known analytical methods, as described above.

[0040] Methods for obtaining a "cell wall-lytic enzyme hydrolysate" include, but are not limited to, methods known to those skilled in the art, methods described in the Examples, or a method comprising the following: (a) treating yeast extract cell body residue with a cell wall-lytic enzyme, and (b) recovering the treated product obtained in (a), or methods similar thereto.

[0041] In another embodiment of the present invention, the degradation product is obtained by a method comprising the following steps: (a) treating yeast extract cell residue with a cell wall-lytic enzyme (preferably glucanase) at about 40 to about 60°C for about 1 to about 24 hours; and (b) recovering the treated product obtained in (a).

[0042] The "yeast extract cell residue" in (a) above is as described above, and is preferably the residue of yeast cells (water-insoluble fraction) after hot water extraction of yeast, and preferably a yeast extract cell residue having a soluble solid content of less than 5% by mass relative to the dry mass thereof.

[0043] The "cell wall-lytic enzyme" in (a) above is as described above, and is preferably glucanase.

[0044] The "treatment" in (a) above is not particularly limited as long as the conditions are such that the cell wall-lytic enzyme can decompose the yeast cell walls contained in the yeast extract cell residue, and can be appropriately changed depending on the origin of the yeast cell walls, the type and / or amount of the cell wall-lytic enzyme, the desired properties, etc. The treatment is usually carried out in a desired solvent (e.g., water). For example, the treatment is carried out using a suspension of the yeast extract cell residue in a solvent (e.g., water). If necessary, the suspension may be subjected to a sterilization treatment (e.g., heat sterilization, filtration sterilization, etc.). Treatment of yeast extract cell residue with a cell wall-lytic enzyme can be carried out, for example, at a temperature above 0°C but below about 100°C (preferably about 10 to about 70°C, more preferably about 25 to about 65°C, and even more preferably about 40 to about 60°C), for about 0.5 to about 120 hours (preferably about 0.5 to about 60 hours, more preferably about 1 to about 24 hours, even more preferably about 3 to about 24 hours, and still more preferably about 12 to about 24 hours), at a pH of about 1 to about 12 (preferably about 2 to about 10, more preferably about 3 to about 8, and even more preferably about 4 to about 6). After the above treatment, the cell wall-lytic enzyme may be inactivated, if necessary, by high-temperature treatment, acid or alkali treatment, or the like.

[0045] In (b) above, the treated product obtained in (a) may be used as is, including the residue (insoluble fraction), as a "cell wall-lytic enzymatic degradation product of yeast extract cell body residue," or, if necessary, may be further purified (e.g., HPLC, ultrafiltration, etc.), concentrated (e.g., air drying, vacuum filtration, etc.), sterilized (e.g., heat sterilization, filtration sterilization, etc.), dried (e.g., air drying, heating, vacuum, spray drying, freeze drying, etc.) and used as a "cell wall-lytic enzymatic degradation product of yeast extract cell body residue." The conditions for these steps can be adjusted as appropriate by those skilled in the art.

[0046] The processed product obtained in (a) in (b) above, including the residue (insoluble fraction), may be used as is as the milk replacer composition of the present invention. Alternatively, the milk replacer composition of the present invention containing the cell wall-lytic enzyme hydrolysate of yeast extract cell residue may be in the form of a cloudy liquid or paste containing the hydrolysate at an appropriate concentration, for example, about 0.001 to about 30% by mass, preferably about 5 to about 20% by mass, on a dry mass basis, in an appropriate medium (preferably water). Alternatively, the milk replacer composition of the present invention may be the hydrolysate itself, and nutrients such as yeast-derived protein and dietary fiber can be ingested by using the composition of the present invention.

[0047] The yeast extract cell residue or its cell wall-lytic enzyme hydrolyzate described above can be used in place of milk in foods and beverages containing milk (cow's milk). For example, the "milk substitute composition" of the present invention may be incorporated into foods and beverages, or may be mixed with foods and beverages before, during, and / or after cooking.

[0048] In one embodiment of the present invention, a milk substitute food or beverage is provided, comprising the yeast extract cell residue or its cell wall-lytic enzymatic hydrolyzate of the present invention and fats and / or carbohydrates. The amount of yeast extract cell residue or its cell wall-lytic enzymatic hydrolyzate in the milk substitute food or beverage of the present invention varies depending on the form of the food or beverage and is not particularly limited. However, the dry mass of the yeast extract cell residue or its cell wall-lytic enzymatic hydrolyzate relative to the mass of the milk substitute food or beverage can be approximately 1 to 30% by mass. The milk substitute food or beverage of the present invention may be consumed as yeast-based milk or used as a milk substitute during cooking. The milk substitute food or beverage of the present invention is a novel milk substitute food or beverage made primarily from yeast, which has a protein-based component, a moderate amount of fats and oils, and a milk-like appearance. If no animal-derived ingredients are used as ingredients, the food or beverage is suitable for vegetarians and vegans who avoid consuming animal-based foods. If fats and oils produced using microorganisms are used as ingredients, the resulting milk substitute food or beverage is a novel milk substitute food or beverage that does not use either animals or plants. The amount of yeast extract cell residue or its cell wall-lytic enzymatic hydrolysate when used as yeast milk for consumption is not particularly limited, but can be approximately 1 to 30% by mass, preferably 2 to 20% by mass, and more preferably 5 to 10% by mass, based on the dry mass of the yeast extract cell residue or its cell wall-lytic enzymatic hydrolysate. Incorporating a larger amount of yeast extract cell residue or its cell wall-lytic enzymatic hydrolysate in yeast milk allows for efficient intake of more yeast-derived proteins, dietary fiber, and other nutrients. While increasing the amount increases the viscosity of the yeast milk, a beverage containing the yeast extract cell residue or its cell wall-lytic enzymatic hydrolysate within the above range can be produced that maintains the desirable mouthfeel of yeast milk while allowing for efficient intake of yeast-derived proteins, dietary fiber, and other nutrients. When used as a milk substitute during cooking, it can be used in foods such as gratins and confectioneries.

[0049] "Oils and fats" as used herein includes, but is not limited to, vegetable oils and fats, animal oils and fats, processed oils and fats, such as edible safflower oil, edible grape oil, edible soybean oil, edible sunflower oil, edible corn oil, edible cottonseed oil, sesame oil, edible rapeseed oil, edible rice bran oil, edible peanut oil, edible olive oil, edible palm oil, edible palm olein, edible palm stearin, edible palm kernel oil, edible coconut oil, edible blended oils, flavored edible oils, beef tallow, lard, chicken oil, fish oil, dairy fat, hydrogenated oils and fats, and oils and fats produced by microorganisms such as yeast.

[0050] The amount of fat or oil contained in the milk substitute food or beverage of the present invention is not particularly limited, as it varies depending on the form of the food or beverage, but is generally 0.1 to 30% by mass relative to the mass of the milk substitute food or beverage. The amount of fat or oil when used as yeast milk is generally 0.1 to 30% by mass, preferably 1 to 10% by mass, and more preferably 2 to 5% by mass relative to the mass of the yeast milk. Incorporating a larger amount of fat or oil into yeast milk can provide richer flavor, a more satisfying taste, and a smoother drinking experience. On the other hand, excessively high amounts can have undesirable effects, such as a decrease in the drinkability of the yeast milk and an increase in the amount of energy ingested. However, if the amount of fat or oil is within the above range, the yeast milk can be made to be easy to drink while providing richness, a more satisfying taste, and a smoother drinking experience, while also providing a beverage that provides adequate energy intake. When used as yeast milk, an appropriate medium (preferably water) can be incorporated in addition to the yeast extract cell residue or its cell wall-lytic enzyme hydrolysate and fat or oil. The amount of medium (preferably water) in the yeast milk is generally 30 to 97% by mass, preferably 40 to 95% by mass, and more preferably 45 to 93% by mass, relative to the mass of the yeast milk. When the amount of medium (preferably water) in the yeast milk is within the above range, a beverage with a good mouthfeel can be produced in which the yeast extract cell body residue or its cell wall-lytic enzymatic hydrolysate and fats and oils are homogeneously dispersed in the medium.

[0051] The term "carbohydrate" as used herein includes, for example, monosaccharides, disaccharides, trisaccharides, tetrasaccharides, oligosaccharides, polysaccharides, starch hydrolysates, reduced starch hydrolysates, etc., and these may be used alone or in combination of two or more kinds. Examples of carbohydrates include, but are not limited to, ketotriose, aldotriose, erythrulose, ribulose, xylulose, lyxose, deoxyribose, psicose, fructose, sorbose, tagatose, allose, altrose, glucose, mannose, gulose, idose, galactose, talose, fucose, fuculose, rhamnose, sedoheptulose, sucrose, lactose, maltose, trehalose, turanose, cellobiose, raffinose, maltotriose, acarbose, stachyose, fructooligosaccharides, galactooligosaccharides, mannanoligosaccharides, glycogen, starch, cellulose, dextrin, corn syrup, powdered sugar, and glucan, which may be used alone or in combination of two or more.

[0052] The milk substitute food and drink of the present invention may further contain additives such as, but not limited to, excipients, lubricants, binders, disintegrants, pH adjusters, solvents, solubilizers, suspending agents, buffers, preservatives, antioxidants, colorants, sweeteners, surfactants, flavorings, etc. These additives may be, for example, known additives, and the amounts used may be adjusted appropriately by those skilled in the art depending on the purpose.

[0053] Alternatively, foods and beverages to which the "milk substitute composition" of the present invention can be applied or which contain the same include, but are not limited to, beverages and foods that contain or are intended to contain milk (for example, cow's milk, soy milk, almond milk, all-milk, coconut milk, etc.) or milk powder, such as soups, dressings, semi-solid dressings, mayonnaise, confectioneries, chocolate, margarine, fat spreads, ice cream, lacto ice cream, ice milk, fresh cream, bread, retort foods, extract seasonings, processed oils and fats, prepared oils and fats, cheese, cheese food, processed cheese, pudding, and other processed foods.

[0054] The amount of the "milk substitute composition" of the present invention to be applied is not particularly limited as long as the object of the present invention can be achieved. The amount of yeast extract cell residue or its cell wall-lytic enzyme decomposition product (dry mass) relative to the total amount of the food, drink, etc. or processed products thereof can be, for example, about 0.001 to about 30% by mass, preferably about 0.01 to about 20% by mass, and more preferably about 0.1 to about 15% by mass.

[0055] In another embodiment of the present invention, there is provided a method for improving the flavor of a milk replacer composition comprising a yeast extract cell residue, the method comprising reducing the total amount of free glutamic acid contained in the residue to less than 0.5% by mass, based on the dry mass of the residue. In another embodiment of the present invention, there is provided a method for improving the flavor of a milk replacer composition comprising a cell wall-lytic enzyme hydrolysate of yeast extract cell residue, the method comprising reducing the total amount of free glutamic acid contained in the hydrolysate to less than 0.4% by mass, based on the dry mass of the hydrolysate. In another embodiment of the present invention, there is provided a use of yeast extract cell residue as a milk replacer composition, wherein the total amount of free glutamic acid contained in the residue is less than 0.5% by mass, based on the dry mass of the residue. In another embodiment of the present invention, there is provided a use of a cell wall-lytic enzyme hydrolysate of yeast extract cell residue as a milk replacer composition, wherein the total amount of free glutamic acid contained in the hydrolysate is less than 0.4% by mass, based on the dry mass of the hydrolysate. The explanation given above regarding the embodiment of the milk replacer composition containing yeast extract cell residue or its cell wall-lytic enzyme decomposition product can be similarly applied to these embodiments of the present invention.

[0056] The present invention will be described in more detail below using examples, but these examples are not intended to limit the scope of the present invention in any way.

[0057] Comparative Example 1 Dry yeast (Hyper Yeast HG-DY, manufactured by Asahi Group Foods Co., Ltd.) was extracted with hot water, and the yeast extract was separated using a nozzle-type continuous centrifuge to obtain a heavy liquid (insoluble fraction). The heavy liquid was sterilized at 125°C for 40 seconds and spray-dried to obtain a yeast extract cell residue as the composition of Comparative Example 1.

[0058] Comparative Example 2 The yeast extract cell residue obtained in Comparative Example 1 was suspended in deionized water to prepare a slurry (solids content 16%), which was sterilized in an autoclave (121°C, 20 minutes), and then 0.2% by mass of glucanase (Denazyme GEL-L1 / R, manufactured by Nagasevita Co., Ltd.) based on the dry mass of the yeast extract cell residue was added at 50°C and pH 5.3, followed by treatment at 50°C for 18 hours. The treated product was then heated to approximately 80°C to inactivate the glucanase, and the treated product was concentrated under reduced pressure using a vacuum concentrator to a concentration of 30% by mass, followed by spray drying to obtain a cell wall-lytic enzyme hydrolyzed product as the composition of Comparative Example 2.

[0059] The compositions of Comparative Examples 1 and 2 were prepared according to Example 1 of Patent Document 1.

[0060] Example 1 The yeast extract cell residue obtained in Comparative Example 1 was suspended in water to prepare a slurry (solid content 16%). Three nozzle-type continuous centrifuges were arranged in series, and solid-liquid separation was performed while adding water to obtain a heavy liquid from which soluble components had been removed. The obtained heavy liquid was sterilized at 125°C for 40 seconds and spray-dried to obtain the yeast extract cell residue as the composition of Example 1.

[0061] Example 2 A post-sterilization heavy liquid prepared in the same manner as in Example 1 was adjusted to conditions of 50°C and pH 5.3, and 0.2 mass% of glucanase (Denazyme GEL-L1 / R, manufactured by Nagasevita Co., Ltd.) based on the dry mass was added, followed by treatment at 50°C for 18 hours. The treated product was treated at 125°C for 40 seconds to sterilize and inactivate the glucanase, and then spray-dried to obtain a cell wall-lytic enzyme decomposition product as the composition of Example 2.

[0062] Test Example 1: The ingredients were mixed according to the compositions shown in Table 1, emulsified in a homogenizer (Homogenizer LAB1000, SMT Co., Ltd.: 20 MPa, twice), and sterilized in an autoclave (121°C, 20 minutes) to obtain milk replacer compositions Formulation 1 and Formulation 2. It was confirmed that both Formulation 1 and Formulation 2 maintained a milky, emulsified appearance at room temperature for a certain period of time (3 days) or more. Formulation 1 was prepared in the same manner as Formulation 23 in Patent Document 1.

[0063]

[0064] [Sensory Evaluation of Formulation 1 and Formulation 2] Formulation 1 and Formulation 2 were subjected to sensory evaluation as follows. Each formulation cooled to 4°C was subjected to sensory evaluation by five expert panelists. For the evaluation items of "umami," "sourness," "milky flavor," and "palatability," Formulation 1 was assigned a score of 0 as the control, and the flavor intensity of the test samples was evaluated based on the following evaluation criteria. Note that it is considered preferable for "umami" and "sourness" to have negative values ​​(weaker than the control), and it is preferable for "milky flavor" and "palatability" to have positive values. Furthermore, the "milky flavor" was evaluated based on the faint sweet aroma after swallowing, mellowness, absence of off-flavors and tastes, and plainness, to determine whether the flavor was similar to animal milk overall.

[0065] [Evaluation criteria] -3 points: Very weak -2 points: Weak -1 point: Slightly weak 0 point: Control +1 point: Slightly strong +2 points: Strong +3 points: Very strong

[0066] [Results] The evaluation results are shown as average values ​​in Figure 1. As a result, Formulation 2 obtained in Test Example 1 had reduced "umami" and "sourness" and increased "milk-like flavor" and "palatability" compared to Formulation 1. It was found that Formulation 2 clearly exhibited more preferable sensory properties as a milk replacer composition than Formulation 1.

[0067] Test Example 2: Formulations 3 and 4 were obtained by mixing the raw materials according to the compositions shown in Table 2. After mixing the raw materials, the mixture was emulsified in a homogenizer (Homogenizer LAB1000, SMT Co., Ltd.: 20 MPa, twice) and sterilized in an autoclave (121°C, 20 minutes) to obtain Formulations 5 to 12, which are milk replacer compositions containing yeast material and fats and oils at different ratios. It was confirmed that all of Formulations 5 to 12 maintained a milky, emulsified, milk-like appearance at room temperature for a certain period of time (3 days or more).

[0068]

[0069] [Sensory Evaluation of Formulations 3 to 12] The resulting Formulations 3 to 12 were subjected to a sensory evaluation as follows. Each formulation cooled to 4°C was subjected to a sensory evaluation by five expert panelists. Formulation 3 was compared with Formulation 4, Formulation 5 with Formulation 6, Formulation 7 with Formulation 8, Formulation 9 with Formulation 10, and Formulation 11 with Formulation 12, with Formulations 3, 5, 7, 9, and 11 serving as controls, respectively. For the evaluation items of "umami," "sourness," "milky flavor," and "palatability," the control was given a score of 0, and the flavor intensity of the test samples was evaluated based on the above evaluation criteria.

[0070] [Results] The average evaluation results of five expert panelists are shown in Figures 2 to 6. As a result, compared to Formula 3, Formulation 4 had reduced "umami" and "sourness," and increased "milk-like flavor" and "palatability," demonstrating favorable sensory properties as a milk replacer composition. Formulation 6, compared to Formula 5, Formulation 8, compared to Formula 7, Formulation 10, compared to Formula 9, and Formulation 12, compared to Formula 11, similarly had reduced "umami" and "sourness," and increased "milk-like flavor" and "palatability," demonstrating favorable sensory properties as a milk replacer composition. The composition of Example 2 exhibited a more favorable flavor than the composition of Comparative Example 2 over a wide concentration range (5% to 20%) and a wide range of fat and oil concentrations (0% to 30%).

[0071] Comparative Examples 3-4, Example 3 The yeast extract cell residue obtained in Comparative Example 1 was suspended in water to prepare a slurry (solid content 16%). Solid-liquid separation was performed using a centrifuge (AvantiJ-26XP, manufactured by Beckman Coulter, Inc.) at 5,000 × g for 5 minutes, and the supernatant was removed. An equal amount of water to the supernatant was added, and the mixture was suspended. Solid-liquid separation was then performed again using the centrifuge, and this procedure was repeated to recover an insoluble fraction. The resulting insoluble fraction was sterilized at 121°C for 20 minutes and lyophilized to obtain the yeast extract cell residue of Example 3. Yeast extract cell residues with different degrees of washing were obtained as the compositions of Comparative Examples 3-4 in the same manner as in Example 3, except that the amount of water added after the first solid-liquid separation was reduced.

[0072] [Comparative Examples 5-6, Example 4] Next, in Comparative Examples 3-4 and Example 3, the insoluble fraction after sterilization was prepared into a slurry (solid content 16%) at 50°C and pH 5.3, and 0.2 mass% of glucanase (Denazyme GEL-L1 / R, manufactured by Nagasevita Co., Ltd.) based on the dry mass was added, followed by treatment at 50°C for 18 hours. The treated product was then treated at 121°C for 20 minutes to sterilize and inactivate the glucanase, and freeze-dried to obtain cell wall-lytic enzyme hydrolysates with different degrees of washing as the compositions of Comparative Examples 5-6 and Example 4.

[0073] Test Example 3 The free amino acid content, phosphoric acid content and citric acid content of each of the compositions obtained in Examples 1 to 4 and Comparative Examples 1 to 6 were measured.

[0074] [Free Amino Acid Analysis] The free amino acid content was measured by the AccQ-Tag Ultra labeling method using an Acquity UPLC analyzer (Waters Corporation, USA). A calibration curve was prepared using an amino acid standard solution type H (Fujifilm Wako Pure Chemical Industries, Ltd.), L-asparagine monohydrate (Fujifilm Wako Pure Chemical Industries, Ltd.), L(+)-glutamine (Fujifilm Wako Pure Chemical Industries, Ltd.), L-tryptophan (Fujifilm Wako Pure Chemical Industries, Ltd.), and γ-aminobutyric acid (Sigma-Aldrich Japan LLC). This method selectively quantified free amino acids in the sample, and their contents (% by mass) were calculated. Note that "total free amino acids" refers to the sum of the free amino acid contents per dry mass of the yeast extract cell residue or cell wall-lytic enzyme hydrolysate. The amino acid contents (% by mass) per dry mass of the yeast extract cell cell residues (Comparative Examples 1, 3-4, and Examples 1 and 3) are shown in Table 3. Similarly, the amino acid contents (% by mass) per dry mass of the cell wall-lytic enzyme hydrolysates (Comparative Examples 2, 5-6, and Examples 2 and 4) are shown in Table 4.

[0075]

[0076] [Acid Component Analysis] The acid component content was measured using a Prominence HPLC Organic Acid Analysis System (Shimadzu Corporation, Japan). Each composition in the Examples and Comparative Examples was prepared into a 5% by mass suspension in deionized water, centrifuged, and the resulting supernatant was filtered through a 0.45 μm pore size filter. This was used as a measurement sample solution for analysis. Phosphoric acid, citric acid, pyruvic acid, malic acid, succinic acid, lactic acid, acetic acid, pyroglutamic acid, and formic acid were measured, and acid components with very low concentrations were excluded to quantify phosphoric acid and citric acid. The acid component content (% by mass) per dry mass of the yeast extract cell cell residue (Comparative Examples 1, 3-4, and Examples 1 and 3), calculated from the obtained measurements, is shown in Table 5. Similarly, the acid component content (% by mass) per dry mass of the cell wall-lytic enzyme hydrolysates (Comparative Examples 2, 5-6, and Examples 2 and 4), is shown in Table 6.

[0077]

[0078] Test Example 4 The soluble solid content of each of the obtained yeast extract cell residue compositions (Comparative Examples 1, 3-4, and Examples 1 and 3) was measured.

[0079] [Measurement of the Percentage of Soluble Solids] The percentage (mass%) of the water-soluble solids contained in the yeast extract cell residue relative to the total solids in the residue was calculated using the following formula (1) after preparing a 10% by mass suspension of each composition of the Examples and Comparative Examples with deionized water.

[0080]

[0081] In the formula (1), "solid content concentration A" represents the mass % of the dried material obtained by drying X g of the target sample at 105° C. for 5 hours, and "solid content concentration B" represents the mass % of the dried material obtained by centrifuging X g of the target sample at 5,000×g for 5 minutes and drying the resulting supernatant at 105° C. for 5 hours. The soluble solid content calculated using formula (1) is shown in Table 7.

[0082]

[0083] Test Example 5 Sensory Evaluation of Yeast Extract Cell Residue The compositions obtained in Comparative Examples 1, 3-4, and Examples 1 and 3 were subjected to a sensory evaluation as follows. First, each material was added to room temperature water to a concentration of 5% by mass, and after thorough stirring, a sensory evaluation was performed by five expert panelists. For the evaluation items of "umami," "sourness," "milky flavor," and "palatability," the composition of Comparative Example 1 was assigned a score of 0 as a control, and the flavor intensity of each sample was evaluated based on the above evaluation criteria.

[0084] The results of the sensory evaluation are shown as average values ​​in Figure 7. Compared to the composition of Comparative Example 1, the compositions of Comparative Examples 3 and 4 also showed a tendency toward reduced "umami" and "sourness," while increasing "milky flavor" and "liking." On the other hand, the compositions of Examples 1 and 3 showed particularly favorable sensory properties, with "umami" and "sourness" reduced to a rating of -2 or less, and "milky flavor" and "liking" increased to a rating of +2 or more. As shown in the free amino acid analysis in Table 3 above, the free amino acid contents of the compositions of Comparative Examples 3 and 4 and Examples 1 and 3 were lower than that of the composition of Comparative Example 1, reflecting the degree of washing in the production method. The compositions of Examples 1 and 3, which showed particularly favorable sensory properties, had a total free amino acid content of 0.48% by mass or less, a sum of phenylalanine, tyrosine, arginine, isoleucine, leucine, valine, methionine, and lysine, which are free amino acids known to impart bitterness, of 0.04% by mass or less, and a glutamic acid content imparting sourness and umami of 0.29% by mass or less. Furthermore, in the compositions of Examples 1 and 3, the contents of alanine and proline, which impart sweetness, were each 0.05% by mass or less. As shown in the acid component analysis in Table 5 above, the contents of phosphoric acid and citric acid in the compositions of Examples 1 and 3, which exhibited particularly favorable sensory properties, were 0.046% by mass or less and 0.011% by mass or less, respectively. As shown by the soluble solids content in Table 7 above, the compositions of Examples 1 and 3, which exhibited particularly favorable sensory properties, contained 3.52% by mass and 4.57% by mass of water-soluble solids, respectively, indicating that the water-soluble flavor-imparting components were lower than those in the comparative examples. These results demonstrate that a material exhibiting favorable sensory properties can be obtained by removing a certain amount of flavor-imparting components from the yeast extract cell residue.

[0085] [Sensory evaluation of cell wall-lytic enzyme hydrolysates] The compositions obtained in Comparative Examples 2, 5-6, and Examples 2 and 4 were subjected to sensory evaluation as follows. First, each material was added to room temperature water to a concentration of 5% by mass, and after thorough stirring, a sensory evaluation was performed by five expert panelists. For the evaluation items of "umami," "sourness," "milky flavor," and "palatability," the composition of Comparative Example 2 was assigned a score of 0 as a control, and the flavor intensity of each sample was evaluated based on the above evaluation criteria.

[0086] The results of the sensory evaluation are shown as average values ​​in Figure 8. Compared to the composition of Comparative Example 2, the compositions of Comparative Examples 5 and 6 also showed a tendency toward decreased "umami" and "sourness," and increased "milky flavor" and "liking." On the other hand, the compositions of Examples 2 and 4 showed particularly favorable sensory characteristics, with "umami" and "sourness" reduced to a rating of -2 or less, and "milky flavor" and "liking" increased to a rating of +2 or more. As shown in the free amino acid analysis in Table 4 above, the free amino acid content of the compositions of Comparative Examples 5 and 6 and Examples 2 and 4 was lower than that of the composition of Comparative Example 2, reflecting the degree of washing in the production method. In particular, the compositions of Examples 2 and 4 had a total free amino acid content of 0.45% by mass or less, a sum of phenylalanine, tyrosine, arginine, isoleucine, leucine, valine, methionine, and lysine, which are free amino acids known to impart bitterness, of 0.06% by mass or less, and a glutamic acid content imparting sourness and umami of 0.24% by mass or less. Furthermore, the sweetening alanine and proline contents were each 0.05% by mass or less in the compositions of Examples 2 and 4. As shown in the acid component analysis in Table 6 above, the compositions of Examples 2 and 4, which exhibited particularly favorable sensory properties, contained 0.109% by mass or less of phosphoric acid and 0% by mass of citric acid. These results demonstrate that the material obtained by treating the yeast extract cell residue, from which a certain amount of flavor components has been removed, with glucanase has favorable sensory properties.

[0087] The composition of the present invention controls the total amount of free amino acids (particularly glutamic acid) and acid components (particularly phosphoric acid) contained in the yeast extract cell residue or its cell wall-lytic enzyme hydrolysate to less than a specific amount, thereby significantly reducing the characteristic flavors and aromas unique to yeast (e.g., umami, sourness, etc.), and can be incorporated into various foods and beverages as a milk replacer composition at higher concentrations than conventional products. Thus, the composition of the present invention can be provided as foods and beverages in various forms, making it easier to ingest yeast-derived proteins, dietary fiber, other nutrients, etc. through such foods and beverages.

Claims

1. A milk replacer composition comprising a yeast extract cell residue, wherein the total amount of free glutamic acid contained in the residue is less than 0.5% by mass based on the dry mass of the residue.

2. The composition according to claim 1, wherein the total amount of free amino acids contained in the residue is less than 1% by weight based on the dry weight of the residue.

3. The composition of claim 1, wherein the residue contains a total amount of phosphoric acid of less than 0.1% by weight based on the dry weight of the residue.

4. The composition of claim 1, wherein the residue is a water-insoluble fraction following hot water extraction of yeast.

5. The composition of claim 1, wherein the residue contains less than 5% by weight of soluble solids based on the dry weight of the residue.

6. A milk replacer composition comprising a cell wall-lytic enzyme hydrolysate of yeast extract cell residue, wherein the total amount of free glutamic acid contained in the hydrolysate is less than 0.4% by mass relative to the dry mass of the hydrolysate.

7. The composition according to claim 6, wherein the total amount of free amino acids contained in the decomposition product is less than 1% by weight based on the dry weight of the decomposition product.

8. The composition according to claim 6, wherein the total amount of phosphoric acid contained in the decomposition product is less than 0.20% by weight based on the dry weight of the decomposition product.

9. A milk replacer composition comprising a cell wall-lytic enzyme hydrolysate of a yeast extract cell residue, wherein the soluble solids content of the residue is less than 5% by mass relative to the dry mass of the residue, as described in claim 6.

10. The composition according to claim 6, wherein the decomposition product is obtained by a method comprising: (a) treating a yeast extract cell residue with a cell wall-lytic enzyme at 40 to 60°C for 1 to 24 hours; and (b) recovering the treated product obtained in (a).

11. The composition of claim 6, wherein the cell wall lytic enzyme is a glucanase.

12. The composition of claim 6, wherein the cell wall lytic enzyme is a glucanase having β-1,3, β-1,4, and / or β-1,6 activity.

13. The composition according to claim 6, wherein the cell wall lytic enzyme is a glucanase derived from Streptomyces.

14. The composition of claim 6, wherein the cell wall lytic enzyme is a glucanase having no protease activity.

15. A milk substitute food or drink comprising the composition according to any one of claims 1 to 14.

16. The milk substitute food or beverage according to claim 15, further comprising 0.1 to 30% by mass of an oil or fat.

17. A method for improving the flavor of a milk replacer composition comprising reducing the total amount of free glutamic acid contained in a milk replacer composition containing yeast extract cell residue to less than 0.5 mass% relative to the dry mass of the residue.

18. A method for improving the flavor of a milk replacer composition, the method comprising reducing the total amount of free glutamic acid contained in a cell wall-lytic enzyme hydrolysate of yeast extract cell residue to less than 0.4 mass% relative to the dry mass of the hydrolysate.

19. Use of a yeast extract cell residue as a milk replacer composition, wherein the total amount of free glutamic acid contained in the residue is less than 0.5% by mass based on the dry mass of the residue.

20. Use of a cell wall-lytic enzymatic hydrolysate of yeast extract cell residue as a milk replacer composition, wherein the total amount of free glutamic acid contained in the hydrolysate is less than 0.4% by mass based on the dry mass of the hydrolysate.

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