Liquid composition

Abstract

To provide a liquid composition curbed in acidity of gluconate even though highly containing the gluconate.SOLUTION: A liquid composition contains gluconate 5.5 mass% or more and has water activity of 0.89 or lower.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a liquid composition. [Background technology]

[0002] Liquid compositions having a sour taste generally contain an organic acid. In consideration of the sour taste, the organic acid is often blended into the liquid composition at a concentration of 1% by mass or less.

[0003] Gluconic acids, a type of organic acid, are known to have various health functions, such as the effect of proliferating bifidobacteria in the intestine (Patent Document 1), the effect of improving the intestinal environment of the small intestine (Patent Document 2), and the effect of increasing ultraviolet resistance of the skin (Patent Document 3). Therefore, gluconic acids are a component that should be actively ingested. The amount of gluconic acids required to obtain the various health functions is 2 to 9 g per day. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Republished Patent No. 1994 / 09650 [Patent Document 2] JP 2019-6735 A [Patent Document 3] JP 2015-27996 A Summary of the Invention [Problem to be solved by the invention]

[0005] Although gluconic acid is known to have an acidity about one-third that of citric acid (see Patent Document 1), when it is incorporated into a liquid composition, it still has a strong acidity for oral ingestion. Therefore, in order to suppress the acidity to a level that allows oral ingestion, the content of gluconic acids in the liquid composition must be limited to about 2 to 3% by mass. However, with a content of about 2 to 3% by mass, if one wishes to ingest an effective amount of gluconic acids to obtain a physiological effect, it is necessary to ingest a large amount of the liquid composition per day, which is a great burden.

[0006] Therefore, the present invention relates to providing a liquid composition which has a high content of gluconic acids and yet has a reduced sour taste of the gluconic acids. [Means for solving the problem]

[0007] As a result of extensive research into suppressing the sour taste of gluconic acids, the present inventors have discovered that, as a phenomenon specific to gluconic acids, a liquid composition with suppressed sour taste can be obtained by setting the water activity of the liquid composition at a certain value or less.

[0008] That is, the present invention provides a liquid composition containing 5.5 mass % or more of gluconic acids and having a water activity of 0.89 or less. Effect of the Invention

[0009] According to the present invention, it is possible to provide a liquid composition which has a high content of gluconic acids and yet has a pleasant sour taste. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] In the present invention, the liquid composition is a composition for oral ingestion that has fluidity at room temperature (20° C.±15° C.) or lower. Examples of liquid compositions include syrup, starch syrup, yogurt sauce, yogurt sauce with ingredients, liquid seasoning, liquid seasoning with ingredients, concentrated drinks, soft drinks, alcoholic drinks, non-alcoholic drinks, etc. Among them, syrup is preferred because it is easy to enjoy the effects of the present invention.

[0011] In the present invention, the gluconic acid compound is gluconic acid (chemical formula: C 6 H 12 O 7 ), glucono-delta-lactone (chemical formula: C 6 H 10 O 6 ) and gluconate. Gluconodeltalactone is an intramolecular ester obtained by dehydrating one molecule of water from gluconic acid. Examples of salts of gluconic acid include salts with alkali metals such as sodium and potassium; salts with alkaline earth metals such as calcium; and magnesium salts. Among these, salts with alkali metals or alkaline earth metals are preferred. Gluconic acids may be solvates or non-solvates, and both are included. Preferred examples of solvates include hydrates and alcohol solvates. Gluconic acids may be used alone or in combination.

[0012] The content of gluconic acids in the liquid composition of the present invention is 5.5% by mass or more. From the viewpoint of obtaining a composition that allows efficient intake of an amount of gluconic acids that exerts a health function, the content is preferably 7% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more. From the viewpoint of obtaining an acidity suitable for consumption, the content is preferably 46% by mass or less, more preferably 40% by mass or less, even more preferably 35% by mass or less, even more preferably 30% by mass or less, and even more preferably 25% by mass or less. The content of gluconic acids in the liquid composition is 5.5% by mass or more, preferably 5.5 to 46% by mass, more preferably 7 to 40% by mass, even more preferably 10 to 35% by mass, even more preferably 15 to 30% by mass, and even more preferably 15 to 25% by mass. In this specification, the content of gluconic acids is expressed as the amount of gluconic acid. In the present invention, the content of gluconic acids is determined by a commercially available enzyme kit method. The sample provided to the kit is appropriately diluted with water. The commercially available enzyme kit used is the F kit manufactured by Roche Diagnostics.

[0013] The liquid composition of the present invention preferably further contains a mineral from the viewpoint of suppressing sourness. Examples of minerals include sodium, potassium, calcium, magnesium, etc. These minerals have a wider upper intake limit range than other minerals, so they are highly safe when ingested in large amounts and are therefore preferable. In addition, these minerals are preferably derived from a buffering agent. The buffering agent may be any that has a pH buffering effect when mixed with gluconic acid, and examples thereof include salts of organic acids such as gluconic acid, citric acid, malic acid, tartaric acid, ascorbic acid, succinic acid, lactic acid, fumaric acid, adipic acid, phytic acid, and acetic acid, and salts of inorganic acids such as phosphoric acid, hydrochloric acid, and carbonic acid. Examples of salts include salts with alkali metals such as sodium and potassium; salts with alkaline earth metals such as calcium; and magnesium salts. These may be solvates or nonsolvates, and both are included. Preferred examples of solvates include hydrates and alcoholates. The buffering agent may be used alone or in combination of two or more kinds. Among them, from the viewpoint of flavor stability of the obtained liquid composition and from the viewpoint of being able to mix gluconic acid at the same time, gluconate is preferred, and one or more kinds selected from sodium gluconate, potassium gluconate, and calcium gluconate are more preferred.

[0014] The content of the mineral in the liquid composition of the present invention can be appropriately determined so as to obtain a desired pH depending on the type of mineral, but from the viewpoint of suppressing sourness, it is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.5% by mass or more. Also, from the viewpoint of obtaining a good flavor with suppressed saltiness and harshness of minerals, it is preferably 6% by mass or less, more preferably 4% by mass or less, even more preferably 3% by mass or less, and even more preferably 2% by mass or less. The content of the mineral in the liquid composition is preferably 0.05 to 6 mass %, more preferably 0.1 to 4 mass %, even more preferably 0.5 to 3 mass %, and still more preferably 0.5 to 2 mass %.

[0015] In the present invention, the mineral content can be determined by the following ICP emission spectrometry (hydrochloric acid extraction). As a specific method, 1 g of the liquid composition is collected and heated at 500 °C for 10 hours to be ashed. Next, 20% hydrochloric acid is added and evaporated to dryness. Next, 20% hydrochloric acid is added again, and the heated extract is filtered to collect the filtrate. The residue on the filter paper is ashed at 500 °C for 1 hour, 20% hydrochloric acid is added and evaporated to dryness, and then 20% hydrochloric acid is added again to perform heated extraction and filtration. The hydrochloric acid extraction of this residue is repeated until there is no residue on the filter paper. All the obtained filtrates are made up to a constant volume with 1% hydrochloric acid and subjected to ICP emission analysis. <ICP emission spectrometer operating conditions> Model: ICPE-9820 [Shimadzu Corporation] RF output: 1100 W Gas flow rate: Plasma gas 15 L / min (argon) : Auxiliary gas 1.2 L / min (argon) : Carrier gas 0.80 L / min (argon) Nebulizer: Coaxial nebulizer Plasma observation position: Horizontal direction Measurement wavelength: Calcium 317.933 nm Sodium 589.592 nm Potassium 766.491 nm

[0016] In the liquid composition of the present invention, the mass ratio of gluconic acids to minerals [minerals / gluconic acids] is preferably 0.002 or more, more preferably 0.003 or more, still more preferably 0.03 or more, from the viewpoint of suppressing sourness, and preferably 0.2 or less, more preferably 0.1 or less, still more preferably 0.08 or less, from the viewpoint of obtaining a good flavor with the salty and eggy flavors of the minerals suppressed. In the liquid composition, the mass ratio of gluconic acids to minerals [minerals / gluconic acids] is preferably 0.002 to 0.2, more preferably 0.003 to 0.1, still more preferably 0.03 to 0.08.

[0017] The liquid composition of the present invention preferably further contains carbohydrates from the viewpoints of reducing water activity to suppress sourness, flavor, and viscosity adjustment. Examples of carbohydrates include sugars and dietary fiber, and from the viewpoints of flavor and viscosity adjustment, sugars are preferred. Examples of carbohydrates include sugars (polysaccharides, disaccharides, monosaccharides) and sugar alcohols.

[0018] Examples of monosaccharides include glucose, fructose, galactose, mannose, xylose, psicose, allose, sorbose, tagatose, ribose, arabinose, rhamnose, amino sugars (glucosamine, N-acetylglucosamine, etc.), etc. Examples of disaccharides include sucrose, maltose, lactose, trehalose, palatinose, cellobiose, nigerose, isomaltose, etc. Examples of polysaccharides include starch, dextrin, maltodextrin, starch syrup, oligosaccharides (lactulose, kestose, raffinose, cyclodextrin, etc.), etc.

[0019] Examples of the sugar raw material include honey, isomerized sugar (fructose glucose liquid sugar, etc.), corn syrup, etc. that mainly contain monosaccharides, maple sugar, etc. that mainly contain disaccharides, and dextrin, maltodextrin, starch syrup, molasses, etc. that mainly contain polysaccharides. In addition, starch hydrolysates obtained by hydrolyzing starch such as corn starch, wheat starch, potato starch, sweet potato starch, tapioca starch, rice, etc. can also be used as raw materials mainly composed of monosaccharides, disaccharides, or polysaccharides depending on the degree of hydrolysis.

[0020] Examples of sugar alcohols include maltitol, erythritol, xylitol, sorbitol, etc. Examples of raw materials for sugar alcohols include reduced maltose syrup, reduced starch syrup, etc.

[0021] The dietary fiber may be water-soluble or insoluble, but water-soluble dietary fiber is preferred from the viewpoint of flavor and viscosity adjustment and water activity reduction.Water-soluble dietary fiber may be indigestible dextrin, polydextrose, inulin, glucan, guar gum, fenugreek gum, tara gum, locust bean gum, cassia gum, glucomannan, psyllium, alginic acid, pectin, agar, carrageenan, xanthan gum, curdlan, gellan gum, gum arabic, pullulan, methylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, mucopolysaccharide (hyaluronic acid, chondroitin sulfate, etc.), etc.Insoluble dietary fiber may be cellulose, hemicellulose, lignin, chitin, chitosan, etc. In the present invention, water-soluble dietary fiber refers to dietary fiber that contains 50% by mass of dietary fiber as measured by the Prosky method (enzyme-gravimetric method) and high performance liquid chromatography method (enzyme-HPLC method) described in the Food Nutrition Labeling Standards System, 3rd Edition (January 2001, edited by Japan Health and Nutrition Food Association, pp. 46-51), and dissolves in 100 g of water at 20° C. at 20 g or more, preferably 30 g or more, and more preferably 40 g or more. In the present invention, insoluble dietary fiber refers to dietary fiber other than the above-mentioned water-soluble dietary fiber.

[0022] The carbohydrates may be used alone or in combination of two or more kinds. Among them, from the viewpoint of the texture and flavor of the liquid composition, carbohydrates are preferred, sugars are more preferred, monosaccharides, disaccharides, and oligosaccharides are even more preferred, and glucose, fructose, and sucrose are even more preferred. As the raw material for these, one or more selected from honey, fructose glucose liquid sugar, oligosaccharides, starch syrup, and corn syrup are more preferred, and honey and fructose glucose liquid sugar are even more preferred. Also, from the viewpoint of storage stability, sugar alcohols are preferred, and maltitol, reduced maltose syrup, reduced starch syrup, and xylitol are more preferred.

[0023] From the viewpoint of reducing water activity, the carbohydrate is preferably water-soluble, and the more hydroxyl groups per molecule, the more preferable. More specifically, from the viewpoint of reducing water activity and suppressing sourness, the ratio of the number of hydroxyl groups in one molecule to the molecular weight [number of hydroxyl groups in one molecule / molecular weight] is preferably 0.020 or more, more preferably 0.022 or more, even more preferably 0.025 or more, and even more preferably 0.027 or more.

[0024] The carbohydrate content in the liquid composition of the present invention is preferably 80% by mass or less, more preferably 75% by mass or less, and even more preferably 70% by mass or less, from the viewpoint of obtaining a composition that allows efficient intake of gluconic acids in an amount sufficient to exert health functions, and is preferably 30% by mass or more, more preferably 32% by mass or more, even more preferably 37% by mass or more, and even more preferably 45% by mass or more, from the viewpoint of reducing water activity and suppressing sourness, and obtaining a flavor and texture suitable for the liquid composition. The carbohydrate content in the liquid composition is preferably 30 to 80 mass %, more preferably 32 to 75 mass %, even more preferably 37 to 70 mass %, and even more preferably 45 to 70 mass %.

[0025] The water content in the liquid composition of the present invention is preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less, and even more preferably 25% by mass or less, from the viewpoint of reducing water activity and suppressing acidity, and is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, from the viewpoint of maintaining fluidity. The water content in the liquid composition is preferably 5 to 50 mass %, more preferably 10 to 40 mass %, even more preferably 15 to 30 mass %, and even more preferably 15 to 25 mass %.

[0026] The mass ratio of water to carbohydrate in the liquid composition of the present invention is preferably 1.0 or less, more preferably 0.6 or less, and even more preferably 0.5 or less, from the viewpoint of reducing water activity and suppressing sourness, and is preferably 0.1 or more, more preferably 0.13 or more, and even more preferably 0.15 or more, from the viewpoint of maintaining fluidity. The mass ratio of water to carbohydrate in the liquid composition is preferably 0.1 to 1.0, more preferably 0.13 to 0.6, and even more preferably 0.15 to 0.5.

[0027] The mass ratio of water to gluconic acids in the liquid composition of the present invention is preferably 5.0 or less, more preferably 3.0 or less, even more preferably 2.0 or less, and even more preferably 1.5 or less, from the viewpoint of suppressing sourness, and is preferably 0.3 or more, more preferably 0.5 or more, and even more preferably 0.6 or more, from the viewpoint of maintaining fluidity. The mass ratio of water to gluconic acids in the liquid composition is preferably 0.3 to 5.0, more preferably 0.5 to 3.0, even more preferably 0.6 to 2.0, and even more preferably 0.6 to 1.5.

[0028] The mass ratio of carbohydrates to gluconic acids in the liquid composition of the present invention is preferably 8.0 or less, more preferably 6.0 or less, and even more preferably 5.0 or less, from the viewpoint of obtaining a composition that allows efficient intake of an amount of gluconic acids that exerts health functions, and is preferably 0.5 or more, more preferably 1.0 or more, and even more preferably 1.5 or more, from the viewpoint of suppressing sourness. The mass ratio of carbohydrates to gluconic acids in the liquid composition is preferably 0.5 to 8.0, more preferably 1.0 to 6.0, and even more preferably 1.5 to 5.0.

[0029] The liquid composition of the present invention may further contain other raw material components that can be blended into the liquid composition within a range that does not impair the effects of the present invention. Examples of such raw material components include sweeteners other than the above carbohydrates (e.g., non-sugar natural sweeteners, synthetic sweeteners, etc.), acidulants other than gluconic acid (e.g., ascorbic acid, etc.), milk components, stabilizers, vegetable juices, fruit juices, pulp, flavorings, colorants, antioxidants, preservatives, antifoaming agents, fats and oils, and trace nutrients such as vitamins. The content of the additives can be appropriately set within a range that does not impair the object of the present invention.

[0030] From the viewpoint of suppressing sourness, the liquid composition of the present invention preferably contains a small amount of acidulant such as organic acid other than gluconic acid. The content of organic acid other than gluconic acid in the liquid composition is preferably 8% by mass or less, more preferably 4% by mass or less, even more preferably 2% by mass or less, and even more preferably substantially 0% by mass, i.e., contains no organic acid other than gluconic acid.

[0031] The liquid composition of the present invention has a water activity of 0.89 or less. From the viewpoint of suppressing sourness and obtaining antiseptic and antifungal properties, the water activity of the liquid composition is preferably 0.82 or less, more preferably 0.75 or less, even more preferably 0.70 or less, even more preferably 0.68 or less, even more preferably 0.62 or less, and even more preferably 0.50 or less, and from the viewpoint of suppressing lipid oxidation to maintain a good flavor and maintaining fluidity, the water activity is preferably 0.20 or more, more preferably 0.25 or more, and even more preferably 0.30 or more. The water activity of the liquid composition is 0.89 or less, preferably 0.20 to 0.82, more preferably 0.25 to 0.75, even more preferably 0.30 to 0.70, even more preferably 0.30 to 0.68, even more preferably 0.30 to 0.62, and even more preferably 0.30 to 0.50. In the present invention, the water activity is measured by adjusting the temperature of the liquid composition to 25° C. and using a water activity meter, as described in the Examples below.

[0032] From the viewpoint of suppressing sourness and obtaining a low water activity necessary for microbial control, the liquid composition of the present invention has a Brix value of preferably 63.2% or more, more preferably 70% or more, and even more preferably 75% or more. Also, from the viewpoint of obtaining a flowability suitable for the liquid composition, the Brix value is preferably 90% or less, more preferably 88% or less, and even more preferably 85% or less. The Brix value of the liquid composition is preferably 63.2 to 90%, more preferably 70 to 88%, and even more preferably 75 to 85%. In this specification, the "Brix value" is a value measured using a sugar refractometer, and is a value equivalent to the mass percentage of an aqueous sucrose solution at 20°C. Specifically, it can be determined according to the method described in the Examples below.

[0033] The pH of the liquid composition of the present invention is preferably 1.5 or more, more preferably 2.0 or more, even more preferably 2.2 or more, and even more preferably 2.4 or more, from the viewpoint of suppressing dissolution of tooth enamel by acid. Also, from the viewpoint of suppressing the growth of microorganisms, the pH is preferably 6 or less, more preferably 5 or less, and even more preferably 4 or less. The pH of the liquid composition is preferably 1.5-6, more preferably 2.0-5, even more preferably 2.2-4, and even more preferably 2.4-4. In the present invention, the pH of the liquid composition is measured by adjusting the temperature of a 10-fold diluted solution to 25° C. and using a pH meter, as described in the Examples below.

[0034] The liquid composition of the present invention can be produced according to a conventional method, and any suitable method can be used. For example, it can be produced by mixing gluconic acids, water, and other components as necessary so that the water activity is 0.89 or less. The order of mixing the gluconic acids, water, and other components as necessary is not particularly limited. Alternatively, the aqueous solution obtained by dissolving gluconic acids and other components mixed as necessary in water can be concentrated to a water activity of 0.89 or less to produce the aqueous solution. Concentration can be performed by known means such as heating concentration and vacuum concentration. When heating and concentrating the aqueous solution, the heating temperature is preferably 140°C or less, more preferably 130°C or less, even more preferably 125°C or less, and even more preferably 120°C or less, in terms of preventing burning, and is preferably 90°C or more, more preferably 95°C or more, even more preferably 100°C or more, and even more preferably 105°C or more, in terms of shortening the concentration time. When the aqueous solution is concentrated by heating, the heating temperature is preferably 90 to 140°C, more preferably 95 to 130°C, even more preferably 100 to 125°C, and still more preferably 105 to 120°C in terms of product temperature. In the case of vacuum concentration, the heating temperature can be further reduced, for example, to preferably 120° C. or lower, more preferably 110° C. or lower, even more preferably 100° C. or lower, and even more preferably 95° C. or lower. In the case of vacuum concentration, the heating temperature of the aqueous solution is preferably 50° C. or higher, more preferably 60° C. or higher, even more preferably 70° C. or higher, and even more preferably 75° C. or higher, from the viewpoint of shortening the concentration time. The heating temperature of the aqueous solution when concentrating under reduced pressure is preferably 50 to 120°C, more preferably 60 to 110°C, even more preferably 70 to 100°C, and still more preferably 75 to 95°C in terms of product temperature. The concentration time varies depending on the treatment scale, but is preferably 10 minutes or more, more preferably 15 minutes or more, and even more preferably 20 minutes or more, and is preferably 60 minutes or less, more preferably 50 minutes or less, and even more preferably 40 minutes or less. The concentration time is preferably 10 to 60 minutes, more preferably 15 to 50 minutes, and further preferably 20 to 40 minutes.

[0035] Since the liquid composition of the present invention contains a high concentration of gluconic acids, it is useful as a liquid composition for promoting the growth of Bifidobacterium bacteria, improving the intestinal environment of the small intestine, or improving ultraviolet resistance, and is expected to exhibit high functional properties of the gluconic acids.

[0036] The liquid composition of the present invention has a controlled acidity suitable for consumption, contains a high amount of gluconic acids, and from the viewpoint of the flavor and texture of the liquid composition, it is preferable that the liquid composition contains 5.5 mass% or more of gluconic acids, has a water activity of 0.89 or less, and has a Brix value of 63.2% or more.

[0037] The liquid composition of the present invention has a controlled acidity suitable for consumption, is high in gluconic acids, and from the viewpoint of the flavor and texture of the liquid composition, it is preferable that the liquid composition contains 5.5 mass% or more of gluconic acids, has a water activity of 0.89 or less, a Brix value of 63.2% or more, and an aqueous solution obtained by diluting the liquid composition 10 times with water has a pH of 1.5 to 6.

[0038] The liquid composition of the present invention preferably contains 5.5% by mass or more of gluconic acids and 0.05 to 6% by mass of minerals, has a water activity of 0.89 or less, a Brix value of 63.2% or more, and has a pH of 1.5 to 6 when the liquid composition is diluted 10 times with water. This is because the liquid composition has a high content of gluconic acids and is therefore safe when ingested in large quantities, and from the viewpoint of the flavor and texture of the liquid composition.

[0039] The liquid composition of the present invention is preferably a liquid composition that contains 10% by mass or more of gluconic acids and 0.05 to 6% by mass of minerals, has a water activity of 0.89 or less, a Brix value of 70% or more, an aqueous solution obtained by diluting the liquid composition 10 times with water has a pH of 1.5 to 6, and is one or more minerals selected from sodium, potassium, calcium, and magnesium, because the liquid composition has a controlled acidity suitable for eating and contains a high content of gluconic acids, and from the viewpoint of the flavor and texture of the liquid composition and high safety when ingested in large amounts.

[0040] The liquid composition of the present invention is preferably a liquid composition that contains 10% by mass or more of gluconic acids, 0.05 to 6% by mass of minerals, and 30% by mass or more of carbohydrates, has a water activity of 0.89 or less, a Brix value of 70% or more, and an aqueous solution obtained by diluting the liquid composition 10 times with water has a pH of 1.5 to 6, and the minerals are one or more selected from sodium, potassium, calcium, and magnesium, because the liquid composition has a low acidity suitable for consumption and a high content of gluconic acids, and also from the viewpoint of the flavor and texture of the liquid composition and high safety when ingested in large quantities.

[0041] In relation to the above-mentioned embodiment, the present invention further discloses the following liquid composition.

[0042] <1> A liquid composition containing 7 to 40% by mass of gluconic acids and having a water activity of 0.20 to 0.75. <2> A liquid composition containing 5.5% by mass or more of gluconic acids, having a Brix value of 63.2 to 90%, and a water activity of 0.20 to 0.75. <3> A liquid composition containing 7 to 40% by mass of gluconic acids, having a Brix value of 63.2% or more, and a water activity of 0.20 to 0.75. <4> A liquid composition containing 7 to 40% by mass of gluconic acids, having a Brix value of 63.2 to 90%, and a water activity of 0.89 or less. <5> A liquid composition containing 5.5% by mass or more of gluconic acids and 30 to 80% by mass of carbohydrates, and having a water activity of 0.20 to 0.75. <6> A liquid composition containing 7 to 40% by mass of gluconic acids and 30% by mass or more of carbohydrates, and having a water activity of 0.20 to 0.75. <7> A liquid composition containing 7 to 40% by mass of gluconic acids and 30 to 80% by mass of carbohydrates, and having a water activity of 0.89 or less.

[0043] <8> A liquid composition containing 5.5% by mass or more of gluconic acids and 30 to 80% by mass of carbohydrates, having a water activity of 0.20 to 0.75 and a Brix value of 63.2 to 90%. <9> A liquid composition containing 7 to 40% by mass of gluconic acids and 30% by mass or more of carbohydrates, having a water activity of 0.20 to 0.75 and a Brix value of 63.2 to 90%. <10> A liquid composition comprising 7 to 40% by mass of gluconic acids and 30 to 80% by mass of carbohydrates, the liquid composition having a water activity of 0.89 or less and a Brix value of 63.2 to 90%. <11> A liquid composition comprising 7 to 40% by mass of gluconic acids and 30 to 80% by mass of carbohydrates, the liquid composition having a water activity of 0.20 to 0.75 and a Brix value of 63.2% or more. <12> A liquid composition containing 7 to 40 mass% gluconic acids, 30 to 80 mass% carbohydrates, and 0.05 to 6 mass% minerals, having a water activity of 0.20 to 0.75 and a Brix value of 63.2 to 90%. EXAMPLES

[0044] [pH measurement] 1 g of the liquid composition was taken and 9 g of water was added. Then, the liquid composition was repeatedly shaken well until it was uniformly dissolved or dispersed to obtain a 10-fold diluted solution. After leaving it in a thermostatic chamber at 25°C for 12 hours or more until the equilibrium state stabilized, the pH was measured using a pH electrode.

[0045] [Brix value measurement] The Brix value (%) of the liquid composition was measured using a digital refractometer: RX-5000i (Atago Co., Ltd.). The liquid composition containing the ingredients is collected from the liquid portion, avoiding the ingredients.

[0046] [Water activity measurement] The water activity of the liquid composition was measured using a water activity meter LabMaster-aw (manufactured by Novacina). 6 g of the liquid composition, which had been kept at 25° C. in advance, was placed in a measurement container and sealed, after which the water activity value of the analysis sample in a steady state in a 25° C. environment was measured using a sensor. The liquid composition containing the ingredients is collected from the liquid portion, avoiding the ingredients.

[0047] [Raw materials] Gluconic acid solution (50%): Gluconic acid solution (50% by mass) (Fuso Chemical Co., Ltd.) Sodium gluconate: Healthy A (Fuso Chemical Co., Ltd.) Potassium gluconate: Healthy K (Fuso Chemical Co., Ltd.) Calcium gluconate monohydrate: Calcium gluconate (Fuso Chemical Co., Ltd.) Citric acid (anhydrous): Purified citric acid (anhydrous) (Fuso Chemical Co., Ltd.) Honey: Sakura Brand Pure Honey (Kato Bee Garden Honpo Co., Ltd.) Fructose-glucose liquid sugar: Fujifract H-100 (Nihon Shokuhin Kako Co., Ltd.) Reduced maltose syrup: Amalti Syrup (Mitsubishi Corporation Life Sciences Ltd.) Reduced starch syrup: Sweet NT (Bussan Food Science Co., Ltd.) Resistant dextrin: Fibersol 2 (Matsutani Chemical Industry Co., Ltd.)

[0048] [Preparation of liquid composition] Example 1 According to the recipe in Table 1, 20 parts by weight of gluconic acid solution (50%) and 100 parts by weight of honey were added and stirred, and then heated and boiled down to 100 parts by weight to obtain a liquid composition.

[0049] Example 2 20 parts by mass of gluconic acid solution (50%), 75 parts by mass of honey, and 5 parts by mass of water were added and stirred to obtain a liquid composition.

[0050] Examples 3 to 14 According to the recipe in Table 1, gluconic acid solution (50%) and honey were added and stirred in the same manner as in Example 1, and then heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0051] Example 15 According to the recipe in Table 1, 40 parts by mass of gluconic acid solution (50%) and 80 parts by mass of fructose glucose liquid sugar were added and stirred, then heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0052] Example 16 According to the recipe in Table 1, 40 parts by mass of gluconic acid solution (50%) and 80 parts by mass of reduced maltose syrup were added and stirred, then heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0053] Example 17 40 parts by mass of gluconic acid solution (50%) and 60 parts by mass of indigestible dextrin were added and stirred, then heated to dissolve, and evaporated water was added until the total amount became 100 parts by mass, to obtain a liquid composition.

[0054] Example 18 40 parts by mass of gluconic acid solution (50%) and 85.7 parts by mass of reduced starch syrup were added and stirred, then heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0055] Example 19 40 parts by mass of gluconic acid solution (50%) and 92.9 parts by mass of reduced starch syrup were added and stirred, then heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0056] Example 20 30 parts by mass of gluconic acid solution (50%), 5.6 parts by mass of sodium gluconate, and 74.3 parts by mass of honey were added and stirred, then heated to dissolve, and further heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0057] Example 21 30 parts by mass of gluconic acid solution (50%), 6 parts by mass of potassium gluconate, and 73.7 parts by mass of honey were added and stirred, then heated to dissolve, and further heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0058] Examples 22 to 24 According to the recipe in Table 1, gluconic acid solution (50%), potassium gluconate, and honey were added and stirred in the same manner as in Example 21, and then the mixture was heated to dissolve, and further heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0059] Example 25 39 parts by mass of gluconic acid solution (50%), 0.6 parts by mass of calcium gluconate, and 74.9 parts by mass of honey were added and stirred, then heated to dissolve, and further heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0060] Comparative Example 1 According to the recipe in Table 2, 40 parts by mass of gluconic acid solution (50%) was diluted with water to 100 parts by mass to obtain a liquid composition.

[0061] Comparative Example 2 100 parts by mass of gluconic acid solution (50%) was used as a liquid composition.

[0062] Comparative Example 3 40 parts by mass of gluconic acid solution (50%), 31.3 parts by mass of honey, and 28.7 parts by mass of water were added and stirred to obtain a liquid composition.

[0063] Comparative Example 4 5.5 parts by mass of citric acid (anhydrous) and 94.5 parts by mass of water were added and stirred to obtain a liquid composition.

[0064] Comparative Example 5 5.5 parts by mass of citric acid (anhydrous) and 105.6 parts by mass of honey were added and stirred, then heated to dissolve, and further heated and boiled down to 100 parts by mass to obtain a liquid composition.

[0065] [Evaluation of liquid composition] (1) Evaluation of sourness Three types of standard aqueous solutions with different acidity intensities were prepared by adjusting the concentration of tartaric acid (L-tartaric acid, Fuso Chemical Co., Ltd.) to 0.3 mass%, 1.0 mass%, and 3.0 mass%. The standard aqueous solutions, the inventive product evaluated, and the comparative product were stored at 25°C for 12 hours or more. A panel of four experts evaluated the sourness of the inventive product and the comparative product according to the following evaluation criteria. The four experts then reached a score based on their discussion. (Evaluation Criteria) 7: The sourness is stronger than that of a 3.0% aqueous solution of tartaric acid. 6: The sourness is almost the same as that of a 3.0% aqueous solution of tartaric acid. 5: The sourness is intermediate between that of a 1.0% tartaric acid solution and a 3.0% tartaric acid solution. 4: The sourness is almost the same as that of a 1.0% aqueous solution of tartaric acid. 3: The sourness is intermediate between that of a 1.0% tartaric acid solution and a 0.3% tartaric acid solution. 2: The sourness is almost the same as that of a 0.3% aqueous solution of tartaric acid. 1: The acidity is weaker than that of a 0.3% aqueous solution of tartaric acid.

[0066] Tables 1 and 2 show the blending composition, analytical values ​​and evaluation results of the liquid composition.

[0067] [Table 1]

[0068] [Table 2]

[0069] As is clear from Tables 1 and 2, it was confirmed that, if the water activity in a liquid composition is set to a certain level or less, a liquid composition having a strong sourness suitable for oral intake can be obtained even if a high content of gluconic acids is added. When citric acid was added, no change in sourness due to a change in water activity was observed (Comparative Examples 4 and 5).

Claims

1. A liquid composition containing 5.5% by mass or more of gluconic acid derivatives and having a water activity of 0.89 or less.

2. The liquid composition according to claim 1, wherein the Brix value is 63.2% or higher.

3. The liquid composition according to claim 1 or 2, wherein the pH of the aqueous solution diluted 10 times with water is 1.5 to 6.

4. The liquid composition according to claim 1 or 2, further containing 0.05 to 6% by mass of minerals.

5. The liquid composition according to claim 4, wherein the mineral is one or more selected from sodium, potassium, calcium, and magnesium.

6. The liquid composition according to claim 1 or 2, further containing 30% by mass or more of carbohydrates.