Yeast extract

Abstract

To provide novel yeast extract that modifies existing yeast extract, to enhance umami of food or drink, and to enhance the flavor of soy sauce or stock.SOLUTION: Yeast extract is prepared in which the total content of γ-decalactone and furfuryl alcohol is less than a specific amount.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a yeast extract having a total amount of γ-decalactone and furfuryl alcohol less than a specific amount. [Background technology]

[0002] Yeast extract is an extract extracted from yeast cells by autolysis, enzymatic decomposition, hot water treatment, acid treatment, etc. It is widely used in food because it can impart a unique umami and richness not found in chemical seasonings. In order to enhance the umami of foods and beverages, the umami of yeast extract has been enhanced.

[0003] For example, Patent Document 1 discloses a method for producing a yeast extract in which the glutamine content and nitrogen content, known as umami indicators, are increased by adjusting the yeast culture conditions in order to enhance the umami taste of the yeast extract. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-201597 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention aims to provide a novel yeast extract that enhances the umami taste of foods, beverages, etc. and enhances the flavor of soy sauce or soup stock by modifying an existing yeast extract. [Means for solving the problem]

[0006] As a result of extensive research, the inventors have discovered that a yeast extract having a total amount of gamma-decalactone and furfuryl alcohol less than a specific amount enhances the umami taste of foods, beverages, etc., and also enhances the unique flavor of soy sauce or soup stock, thereby completing the present invention.

[0007] That is, the present invention provides the following yeast extract. [1] A yeast extract containing less than 400 ppb of gamma-decalactone and furfuryl alcohol in total based on the solid content mass. [2] The yeast extract according to [1], which contains less than 200 ppb of gamma-decalactone and less than 200 ppb of furfuryl alcohol based on the solid content mass. [3] The yeast extract according to [1] or [2] for enhancing umami flavor. [4] The yeast extract according to [1] or [2] for enhancing the flavor of soy sauce or soup stock.

[0008] The present invention also provides the following foods and beverages. [5] A food or drink comprising the yeast extract according to any one of [1] to [4]. [6] The food or beverage described in [5], further containing soy sauce or dashi, or having a soy sauce flavor or dashi flavor.

[0009] Furthermore, the present invention provides the following method for producing a yeast extract. [7] A method for producing a yeast extract, comprising contacting a composition containing a yeast cell extract with a synthetic adsorbent.

[0010] Furthermore, the present invention provides a method for enhancing the umami taste or flavor of a yeast extract, comprising: [8] contacting a composition containing a yeast cell extract with a synthetic adsorbent; A method for enhancing the umami taste of said composition or for enhancing the flavor of soy sauce or dashi. Effect of the Invention

[0011] The yeast extract of the present invention, in which the total amount of γ-decalactone and furfuryl alcohol is less than a specific amount, can enhance the umami of a food or drink, as compared with a yeast extract in which the total amount is equal to or greater than the specific amount. Furthermore, by adding the yeast extract of the present invention to soy sauce or stock, or a food or drink containing them, the unique flavor of soy sauce or stock can be enhanced, as compared with a case in which the yeast extract is added in which the total amount is equal to or greater than the specific amount. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] [Definition] In this specification, yeast extract is a general term for extracts extracted from yeast cells by methods applicable to the production of foods and beverages (e.g., autolysis, enzymatic decomposition, hot water treatment, alkali treatment, acid treatment, etc.). The yeast extract contains at least a cell extract from yeast cells, or a cell extract whose component contents have been increased or decreased by a component adjustment treatment.

[0013] In this specification, the component adjustment treatment refers to a treatment for increasing or decreasing the ratio of a specific component (which may be multiple types of components) other than water contained in a specific composition to the solid mass of the composition. For example, simply subtracting water from an extract does not fall under the category of component adjustment treatment.

[0014] In this specification, ppb means parts per billion (10 -9 ) That is, 1 ppb is 10 -9 Equivalent to g / g.

[0015] [Yeast extract and its manufacturing method] The yeast extract of the present invention is characterized in that the total amount of γ-decalactone and furfuryl alcohol is less than a specific amount.

[0016] (γ-decalactone, furfuryl alcohol) γ-Decalactone is a compound with the CAS number 706-14-9. Furfural alcohol is a compound with the CAS number 98-0-0 and is also called 2-furyl carbinol and 2-(hydroxymethyl)furan.

[0017] The total amount of γ-decalactone and furfural alcohol in the yeast extract of the present invention is less than 400 ppb based on the solid mass of the yeast extract. From the viewpoint of significantly exhibiting the effects of the present invention, it is preferably 200 ppb or less, more preferably 100 ppb or less, still more preferably 80 ppb or less, even more preferably 50 ppb or less, and particularly preferably 20 ppb or less. The total amount of γ-decalactone and furfural alcohol in the yeast extract of the present invention may be, for example, 0.00001 ppb or more, 0.001 ppb or more, or 0.01 ppb or more based on the solid mass of the yeast extract.

[0018] From the viewpoint of significantly exhibiting the effects of the present invention, in the yeast extract of the present invention, γ-decalactone is, for example, less than 200 ppb, preferably 100 ppb or less, more preferably 50 ppb or less, still more preferably 40 ppb or less, even more preferably 25 ppb or less, and particularly preferably 10 ppb or less; and furfural alcohol is, for example, less than 200 ppb, preferably 100 ppb or less, more preferably 50 ppb or less, still more preferably 40 ppb or less, even more preferably 25 ppb or less, and particularly preferably 10 ppb or less.

[0019] The contents of γ-decalactone and furfural alcohol in the present invention can be measured, for example, using a gas chromatograph mass spectrometer (GC / MS). When GC / MS is used for the measurement method, the conditions and methods described in <GC / MS analysis conditions> and <Preparation of GC / MS sample> described in the following examples shall be used.

[0020] The total nitrogen content in the yeast extract of the present invention is not particularly limited, but is, for example, 6% by mass to 16% by mass based on the solid mass of the yeast extract.

[0021] The content of nucleic acid in the yeast extract of the present invention is not particularly limited, but is, for example, 5% by mass to 25% by mass relative to the mass of the solid content of the yeast extract.

[0022] (Excipients) The yeast extract of the present invention may further contain an excipient. Examples of excipients include salt, starch hydrolysates (dextrin, syrup powder, etc.), sugars (monosaccharides (glucose, fructose, etc.), disaccharides (e.g., sucrose, lactose, maltose, trehalose, etc.), oligosaccharides (cellooligosaccharides, maltooligosaccharides, fructooligosaccharides, etc.), sugar alcohols (xylitol, sorbitol, lactitol, maltitol, etc.), reduced glycation products, etc.), and dietary fiber (e.g., indigestible dextrin, polydextrose, guar gum enzyme hydrolysates, etc.). These excipients may be used alone or in combination of two or more.

[0023] When the yeast extract of the present invention contains an excipient, the total content of the excipient is not particularly limited, but may be, for example, 0.1 to 90 mass%, preferably 3 to 80 mass%, more preferably 4 to 75 mass%, and even more preferably 5 to 70 mass%, relative to the total amount of the yeast extract.

[0024] (emulsifier) The yeast extract of the present invention can further contain an emulsifier. The emulsifier is not particularly limited, but examples thereof include sucrose fatty acid ester, glycerin fatty acid ester (e.g., monoglycerin fatty acid ester, polyglycerin fatty acid ester, polyglycerin condensed ricinoleic acid ester, organic acid monoglyceride, etc.), propylene glycol fatty acid ester, sorbitan fatty acid ester, lecithin, enzymatically decomposed lecithin, enzymatically treated lecithin, sodium stearoyl lactate, calcium stearoyl lactate, Quillaja extract, saponin, polysorbate (e.g., polysorbate 20, polysorbate 60, polysorbate 65, polysorbate 80), etc. These emulsifiers may be used alone or in combination of two or more.

[0025] When the yeast extract of the present invention contains an excipient, the total content of the emulsifier is not particularly limited, but is preferably 0.01 to 2 mass%, more preferably 0.05 to 1 mass%, and even more preferably 0.1 to 0.5 mass%, relative to the total amount of the composition.

[0026] (Other ingredients) The yeast extract of the present invention may further contain other ingredients in addition to γ-decalactone, furfuryl alcohol, excipients and emulsifiers, so long as the effects of the present invention are not impaired. Examples of such other ingredients include salt, sugars, amino acid-based umami seasonings (glutamic acid salts such as sodium L-glutamate, ammonium L-glutamate, potassium L-glutamate, calcium L-glutamate, magnesium L-glutamate, etc.; sodium L-aspartate; glutamylvalylglycine, glycine, DL-alanine, etc.), nucleic acid-based umami seasonings (disodium 5'-inosinate, disodium 5'-guanylate, disodium 5'-uridylate, disodium 5'-cytidylate, disodium 5'-ribonucleotide, calcium 5'-ribonucleotide, etc.), organic acids or salts thereof (disodium succinate, succinic acid, trisodium citrate, Potassium gluconate, calcium citrate, acetic acid, etc.), inorganic salts (potassium chloride, sodium phosphate, potassium phosphate, calcium chloride, magnesium sulfate, etc.), amino acids (arginine, lysine, etc.), protein hydrolysates, meat and seafood-derived ingredients (chicken extract, pork extract, beef extract, dried bonito extract, dried bonito powder, etc.), vegetable-derived ingredients (vegetable powder, vegetable extract, shiitake mushroom extract, etc.), seaweed-derived ingredients (kelp extract, dried kelp powder, etc.), alcohols, isotonicity agents (sorbitol, etc.), buffers (sodium acetate, etc.), preservatives (sodium nitrite, etc.), antioxidants (L-ascorbic acid, etc.), colorants (safflower pigment, etc.), and pH adjusters (sodium acetate, etc.). These ingredients may be used alone or in combination of two or more.

[0027] (form) The form of the yeast extract of the present invention is not particularly limited, and examples thereof include solid forms (eg, powder, paste, granules, tablets, etc.) and liquid forms (eg, solutions, dispersions, etc.).

[0028] (Application) The yeast extract of the present invention may be added directly to food and drink for use in the production of the food and drink, or may be used to produce a preparation to be added to food and drink. Specific embodiments of the food and drink include the food and drink described in the section below under [Food and drink].

[0029] The yeast extract of the present invention has the effect of enhancing umami taste, and therefore can be applied to food and drink products to enhance the umami taste thereof.

[0030] In addition, the yeast extract of the present invention has the effect of enhancing the flavor characteristic of soy sauce or soup stock. Therefore, the yeast extract of the present invention can be used, without particular limitation, for example, in food and drink containing soy sauce or soup stock to enhance the flavor characteristic of soy sauce or soup stock.

[0031] [Production method of yeast extract] The yeast extract of the present invention can be obtained by subjecting a composition containing a yeast cell extract to a component adjustment treatment to reduce the amount of γ-decalactone, furfuryl alcohol, or both of these components.

[0032] (Composition containing yeast cell extract) Compositions containing yeast cell extracts include, for example, extracts extracted from yeast cells by autolysis, enzymatic hydrolysis, hot water treatment, alkali treatment, acid treatment, etc., as well as processed yeast cell extracts such as yeast extracts.

[0033] The yeast cells from which the yeast cell extract or processed product thereof is derived are not particularly limited, and examples thereof include one or more unicellular organisms selected from the group consisting of the genera Saccharomyces, Cyberlindnera, Debaryomyces, Candida, Yarrowia, Schizosaccharomyces, Zygosaccharomyces, Pichia, Kluyveromyces, Williopsis, Galactomyces, Torulaspora, and Rhodotorula. Among them, the yeast used in the present invention is preferably one or more species selected from the genera Saccharomyces, Cyberlindnera, Candida, and Yarrowia, more preferably one or more species selected from the group consisting of Saccharomyces cerevisiae (such as brewer's yeast and baker's yeast), Saccharomyces pastorianus, torula yeast (Cyberlindnera jadinii; also known as Candida utilis), Candida sake, Yarrowia lipolytica (also known as Candida lipolytica), and Candida tropicalis, and even more preferably Saccharomyces cerevisiae, torula yeast, or a combination thereof.

[0034] The culture format of the yeast is not particularly limited and may be batch culture, fed-batch culture, continuous culture, or the like.

[0035] The extraction process for the above yeast is not particularly limited, and any extraction method applicable to the production of food and beverages, such as autolysis, enzymatic differentiation, hot water treatment, alkali treatment, or acid treatment, can be used alone or in combination of two or more.

[0036] The yeast cell extract obtained by the above extraction process may be subjected to a component adjustment process as it is, or may be processed into a dried product or the like, and then optionally stored and then subjected to a component adjustment process.

[0037] The form of the composition containing the yeast cell extract may be liquid, paste, powder, solid, etc., but in order to perform the component adjustment treatment, it is preferable to use the composition in liquid form. The liquid to be contacted with the synthetic adsorbent can be dissolved in water and diluted before use. The degree of dilution is not particularly limited, but it is preferable that the solid content of the composition is adjusted to 0.01 to 40% by weight, preferably 1 to 20% by weight, based on the total amount of the composition.

[0038] (Component adjustment processing) When producing the yeast extract of the present invention, the composition containing the yeast cell extract or its dried product is subjected to a component adjustment treatment, whereby the yeast cell extract is adjusted to have a yeast extract composition in which the total amount of γ-decalactone and furfuryl alcohol is less than a specific amount.

[0039] The component adjustment treatment used in the production method of the present invention may be, for example, one type of treatment alone or a combination of two or more types of treatments selected from the group consisting of purification treatments using synthetic adsorbents, ion exchange resins, etc., adsorption filtration treatments using activated carbon, silica gel, zeolite, activated earth, diatomaceous earth, acidic earth, synthetic adsorbents, etc., filtration treatments such as ultrafiltration and microfiltration, and degassing treatments for removing gas components from liquids by vacuum or filling with inert gas, etc. Among these, it is preferable that the production of the yeast extract of the present invention includes at least a purification treatment using a synthetic adsorbent.

[0040] When the yeast cell extract-containing composition contains insoluble solids, it is preferable to subject the composition to an adsorptive filtration treatment prior to the purification treatment.

[0041] In this specification, the synthetic adsorbent refers to an insoluble three-dimensional cross-linked polymer that does not substantially have an ion exchange group. Examples of such synthetic adsorbents include aromatic resins such as polystyrene and styrene-divinylbenzene copolymers; aromatic modified resins obtained by further modifying aromatic resins with bromine or the like; acrylic acid ester resins; methacrylic acid ester resins; and methacrylic resins. Among them, the synthetic adsorbent used in the present invention is preferably an aromatic resin, and more preferably a styrene-divinylbenzene copolymer.

[0042] The aromatic resins may be one or a combination of two or more of the following: polystyrene resins such as Amberlite XAD-16 (manufactured by Rohm and Haas); styrene-divinylbenzene copolymers such as Diaion HP-20, Sepabeads SP700, and SP70 (all manufactured by Mitsubishi Chemical Corporation); acrylic ester resins such as Amberlite XAD-7HP (manufactured by Rohm and Haas); aromatic modified resins such as Sepabeads SP207 (manufactured by Mitsubishi Chemical Corporation); and methacrylic ester resins such as Diaion HP2MGL (manufactured by Mitsubishi Chemical Corporation).

[0043] As a method for passing yeast extract through a synthetic adsorbent, a column system is preferably used, and yeast extract can be used in an amount of 1 to 200 times, preferably 5 to 50 times, the amount of the synthetic adsorbent used in a column or resin tower packed with the synthetic adsorbent.

[0044] The yeast extract obtained as described above can be used as it is or after concentration to form a liquid or paste-like preparation, or it can be powdered by adding known excipients such as dextrin, lactose, or gum arabic as appropriate after a drying process.

[0045] (Other processing) The production method of the present invention may further include a step of removing contaminants by filtration or centrifugation.

[0046] The production method of the present invention preferably further includes a sterilization step.

[0047] The production method of the present invention may include a drying step for partially concentrating or preparing a dried product, depending on the mode of use. The method for removing water is not particularly limited, and may be reduced pressure drying, freeze drying, spray drying, drum drying, or the like.

[0048] When the above drying step is carried out, it is preferable to add an excipient to the yeast extract before the drying step. Specific examples of the excipient and the amount of use are the same as those of the excipient described in the above [Yeast extract] section.

[0049] [Food and beverages] Examples of the food and drink of the present invention include the food and drink containing the yeast extract of the present invention described above in the section [Yeast extract].

[0050] The food and drink of the present invention is not particularly limited, but examples thereof include instant foods such as instant noodles and instant soups; retort foods; cooked foods such as udon, ramen, soba, pasta, fried chicken, curry, and oden; processed meat products such as roast pork, yakitori, roast beef, ham, sausage, bacon, dry sausage, and beef jerky; processed seafood products such as kabayaki, mirin-boshi, fish ham, fish sausage, kamaboko, chikuwa, and hampen; processed foods such as pickles and other vegetable products, processed fruit products, processed seafood products, and processed grain products; seasonings such as solid bouillon, powdered soup stock, miso, powdered miso, soy sauce, powdered soy sauce, moromi, fish sauce, noodle soup, sauce, ketchup, mayonnaise, sauce, dressing, yakiniku sauce, edible oil, spices, and ramen soup; potato chips, snacks, grilled foods, Examples of such confectionery include confectionery, tablets, capsule confectionery, film confectionery, candy, chewing gum, chocolate, and other confectionery; Japanese confectionery such as okaki, senbei, okoshi, manju, candy, dango, and castella; soft drinks (flavored water, carbonated drinks, fruit juice drinks, dairy drinks, tea drinks, and other drinks with an alcohol content of less than 1%; alcoholic drinks (chuhai, cocktails, and other drinks with an alcohol content of 1% or more); patisseries such as cookies, biscuits, crackers, pies, sponge cakes, castella, donuts, waffles, puddings, butter cream, custard cream, cream puffs, jellies, hot cakes, and bread; frozen desserts such as ice cream, ice milk, lacto ice cream, and frozen desserts; dairy products such as yogurt and cheese; syrup, jam, and the like. Among these, the food and drink of the present invention is preferably a food and drink that contains soy sauce or dashi, or that has a soy sauce or dashi flavor, more preferably soy sauce or noodle soup, and even more preferably noodle soup.

[0051] The yeast extract content (solid content equivalent) of the food or beverage of the present invention is not particularly limited and can be adjusted appropriately depending on the type of food or the purpose of use, etc., and is, for example, 0.01 to 20 mass%, 0.1 to 15 mass%, or 1 to 10 mass% relative to the total amount of the food or beverage.

[0052] The yeast extract content of the food or beverage of the present invention is not particularly limited and may be adjusted as appropriate depending on the type of food or the purpose of use, but from the viewpoint of significantly achieving the effects of the present invention, the total amount of γ-decalactone and furfuryl alcohol is adjusted to be less than 4 ppb, preferably 2 ppb or less, more preferably 1 ppb or less, even more preferably 0.8 ppb or less, even more preferably 0.5 ppb or less, and particularly preferably 0.2 ppb or less, based on the total amount of the food or beverage.

[0053] The total amount of γ-decalactone and furfuryl alcohol in the food or drink of the present invention may be, for example, 0.0000001 ppb or more, 0.00001 ppb or more, or 0.0001 ppb or more relative to the total amount of the food or drink.

[0054] The content of yeast extract in the food or beverage of the present invention is not particularly limited and may be adjusted as appropriate depending on the type of food or the purpose of use, but from the viewpoint of significantly achieving the effects of the present invention, the content of γ-decalactone is adjusted to, for example, less than 2 ppb, preferably 1 ppb or less, more preferably 0.5 ppb or less, even more preferably 0.4 ppb or less, even more preferably 0.25 ppb or less, and particularly preferably 0.1 ppb or less, relative to the total amount of the food or beverage.

[0055] The content of yeast extract in the food or beverage of the present invention is not particularly limited and may be adjusted as appropriate depending on the type of food or the purpose of use, etc., but from the viewpoint of prominently achieving the effects of the present invention, the content of furfuryl alcohol is adjusted to, for example, less than 2 ppb, preferably 1 ppb or less, more preferably 0.5 ppb or less, even more preferably 0.4 ppb or less, even more preferably 0.25 ppb or less, and particularly preferably 0.1 ppb or less, relative to the total amount of the food or beverage.

[0056] [Method for enhancing the umami taste of a composition or for enhancing the flavor of soy sauce or dashi] The method of the present invention is characterized in that it comprises contacting a composition containing a yeast cell extract with a synthetic adsorbent, and is for enhancing the umami taste of the composition or for enhancing the flavor of soy sauce or dashi.

[0057] The composition containing the yeast cell extract may be one described in the section entitled "Yeast Extract." Those skilled in the art will be able to understand the details of other embodiments from the above description. EXAMPLES

[0058] The present invention will be described in more detail below based on experimental examples and examples, but the present invention is not limited by these examples. In the examples, "parts" and "%" mean "parts by mass" and "% by mass", respectively, unless otherwise specified. In addition, the "*" mark in the text indicates that the product is manufactured by San-Ei Gen F.F.I. Co., Ltd., and the "※" mark in the text indicates that the product is a registered trademark of San-Ei Gen F.F.I. Co., Ltd.

[0059] [Test Example 1. Preparation of yeast extract sample] (Preparation of yeast extract with reduced γ-decalactone and furfuryl alcohol) 150 g of commercially available yeast extract (Vertex 1G20P, Fuji Food Industry Co., Ltd.) was mixed with 850 g of ion-exchanged water and stirred and dissolved at 40° C. for 30 minutes. 3.0 g of activated carbon (Takecol 50WG-T, Osaka Gas Chemicals Co., Ltd.) was added to the solution and stirred and mixed at room temperature for 30 minutes. The activated carbon was removed by filtration, and 911.2 g of yeast extract filtrate was obtained.

[0060] The yeast extract filtrate obtained in the previous step was passed through a resin tower packed with 50 mL of synthetic adsorbent SP700 (manufactured by Mitsubishi Chemical Corporation) under conditions of SV = 6.0, and 911.2 g of yeast extract (Example 1) was obtained as the effluent with a Brix value of 14.7°.

[0061] (Preparation of yeast extract of comparative example) 150 g of the same commercially available yeast extract as above (Vertex 1G20P, Fuji Food Industry Co., Ltd.) was mixed with 850 g of ion-exchanged water and dissolved by stirring at 40° C. for 30 minutes to obtain 1000 g of a dissolved mixture (Comparative Example 1).

[0062] Using the yeast extracts of Example 1 and Comparative Example 1 as samples, the aroma components were measured with a gas chromatograph mass spectrometer (GC / MS). The measurement conditions were as follows. <GC / MS Analysis Conditions> GC: Agilent Technologies 7890A GC MS: Agilent Technologies 5975C Inert XL MSD Capillary column: Agilent Technologies DB-WAX, length 60 m, inner diameter 0.25 mm, film thickness 0.25 μm Temperature program: Hold at 50 °C for 2 minutes → 3 °C / min → 220 °C Carrier gas: Helium Inlet pressure: 25 psi, constant pressure mode <Preparation of GC / MS Sample> (1) To 9 g of the sample, 50 μg of 3-heptanol was added as an internal standard, and 300 mL of diethyl ether was added and stirred. (2) The diethyl ether layer was separated, and the concentrated product approximately 50 - 1000 times was used as the GC / MS sample. Note that the concentration factor can be appropriately adjusted according to the amount of the component to be measured in the sample.

[0063] The contents per solid mass of γ-decalactone and furfuryl alcohol in the yeast extracts of Example 1 and Comparative Example 1 determined by the GC / MS method were as shown in Table 1.

[0064]

Table 1

[0065] [Test Example 2. Verification of the Effect on the Flavor of Yeast Extract] (Preparation of Mentsuyu) Using the following production method, Mentsuyu A (3-fold concentrated product) used in this test example was produced. (1) Add raw materials 1 - 11 in Table 2 and heat to dissolve. (2) When the temperature reaches 80 °C, fill the container with a hot pack.

[0066] [Table 2]

[0067] (Preparation of test samples) First, 1.0 mass % of the yeast extract of Example 1 described above was added in terms of solid content to 99 mass % of the above noodle soup A to prepare a noodle soup (Example 2-B). Next, γ-decalactone or furfuryl alcohol was added to Example 2-B so that the total amount of the noodle soup was 20 ppb to prepare noodle soup (GD7 in Tables 3 and 4, FA7 in Tables 5 and 6). The obtained noodle soup was diluted to various concentrations using the noodle soup of Example 2-B to prepare dilution series GD1 to 6 and FA1 to 6 (component addition amount 0.1 to 20 ppb). The above noodle soups were used as sensory test samples.

[0068] (Control sample for sensory evaluation) As control samples for the sensory evaluation, sample S1 (0.2% by mass of sodium 5'-ribonucleotide, 99.8% by mass of noodle soup A) and sample S2 (1.0% by mass of the yeast extract of Comparative Example 1 as solid content, the remainder being noodle soup A) were prepared.

[0069] (Sensory evaluation) The obtained test samples were subjected to a sensory evaluation by the following method. The sensory evaluation panel consisted of 10 people engaged in food research and development. The panelists drank the samples completely and evaluated the taste and the smell (retronasal flavor) felt as it passed from the oral cavity through the pharynx to the nasal cavity. (1) First, the panelists were asked to take a sip each of sample S1 and sample S2. (2) The panelists confirmed that sample S1 had a stronger umami taste and a stronger flavor characteristic of soy sauce and dashi than sample S2 containing the yeast extract of Comparative Example 1. The test samples were then evaluated for the intensity of umami taste and the flavor characteristic of soy sauce and dashi, with sample S1 being given a score of 2, sample S2 being given a score of 0, and an intermediate intensity between samples S1 and S2 being given a score of 1.

[0070] (result) The results are shown in Tables 3 to 6. The less γ-decalactone and furfuryl alcohol there were in the noodle soup, the more the umami taste of the noodle soup and the flavors specific to soy sauce and dashi stock were enhanced. This shows that the less γ-decalactone and furfuryl alcohol there were in the yeast extract added to the noodle soup, the more the umami taste and the flavors specific to soy sauce and dashi stock were enhanced.

[0071] [Table 3]

[0072] [Table 4]

[0073] [Table 5]

[0074] [Table 6]

Claims

1. The yeast extract (excluding those containing p-mentha-8-S-glutathionyl-3-one contained in a reaction product of a glutathione-containing yeast extract and D-pulegone as an active ingredient) has a gamma-decalactone and furfuryl alcohol content of 100 ppb or less, respectively, relative to the solid content mass, and the yeast extract is used for foods and beverages having umami taste, with the gamma-decalactone and furfuryl alcohol contents in the foods and beverages being each 1 ppb or less.

2. The yeast extract according to claim 1 for enhancing umami taste.

3. The yeast extract according to claim 1 for enhancing the flavor of soy sauce or soup stock.

4. A food or beverage having an umami taste, comprising the yeast extract described in any one of claims 1 to 3, and having a gamma-decalactone and furfuryl alcohol content of 1 ppb or less each.

5. The food or drink according to claim 4, further comprising soy sauce or dashi, or having a soy sauce flavor or dashi flavor.

6. A method for producing a yeast extract, comprising contacting a composition containing a yeast cell extract with a synthetic adsorbent of a styrene-divinylbenzene copolymer type, wherein the contents of γ-decalactone and furfuryl alcohol relative to the solid mass of the yeast extract are each 100 ppb or less (with the proviso that the yeast extract does not contain, as an active ingredient, p-mentha-8-S-glutathionyl-3-one contained in a reaction product of a yeast extract containing glutathione and D-pulegone).

7. The present invention comprises contacting a composition containing a yeast cell extract (excluding those containing p-mentha-8-S-glutathionyl-3-one contained in a reaction product of a yeast extract containing glutathione and D-pulegone as an active ingredient) with a synthetic adsorbent of a styrene-divinylbenzene copolymer type, A method for enhancing the umami taste of the composition, or for enhancing the flavor of soy sauce or dashi, wherein the composition is used in a food or drink having an umami taste.

Images