Method for reducing acridity of silkworm powder, method for reducing oxidation odor, and method for producing silkworm powder

Abstract

The present invention addresses the problem of providing a method for reducing the acridity or oxidation odor of silkworm powder. A method for solving the problem of the present invention is characterized in that vitamin C or a derivative thereof is added in a silkworm powder production step.

Description

Method for reducing fishy smell of silkworm powder, method for reducing oxidative odor, and production method

[0001] The present invention relates to a method for reducing fishy smell of silkworm powder, a method for reducing oxidative odor, and a production method.

[0002] With the rapid increase in population, there is a concern about the occurrence of a "protein crisis" where the demand for protein exceeds the supply. As one solution to this problem, the utilization of insect food and alternative meat has attracted attention. In particular, insect food is rich in protein compared to meat and fish, and has a low environmental impact during production, so it is highly expected as an alternative protein source to meat and fish.

[0003] Since silkworms are relatively rich in protein, they have attracted attention as an alternative protein. Silkworms grow on mulberry leaves, and mulberry leaves contain imino sugars such as 1-deoxynojirimycin, which has an effect of suppressing blood sugar rise. Since imino sugars are also accumulated in the bodies of silkworms that have ingested mulberry leaves, an effect of suppressing blood sugar rise can be obtained by ingesting silkworm powder (Patent Document 1). However, silkworm powder has a peculiar fishy smell and oxidative odor, which can be an obstacle to continuous ingestion.

[0004] Japanese Patent Laid-Open No. 8-337530

[0005] An object of the present invention is to provide a method for reducing the fishy smell or oxidative odor of silkworm powder.

[0006] As a result of intensive studies to solve the above problems, the present inventors have found that by adding vitamin C or its derivative to a slurry obtained by mixing silkworm crushed matter and water in the production process of silkworm powder, the fishy smell and oxidative odor are reduced, and the present invention has been completed.

[0007] The present invention includes the following embodiments: [1] A method for reducing the bitterness of silkworm powder, characterized by adding vitamin C or a derivative thereof in the manufacturing process of silkworm powder. [2] The method for reducing the bitterness of silkworm powder according to [1], wherein the manufacturing process of silkworm powder includes a step of heating a silkworm slurry obtained by mixing crushed silkworms and water, and is characterized by adding vitamin C or a derivative thereof to the silkworm slurry. [3] The method for reducing the bitterness of silkworm powder according to [2], wherein a silkworm slurry to which vitamin C or a derivative thereof has been added in advance is heated. [4] The method for reducing the bitterness of silkworm powder according to [2], wherein vitamin C or a derivative thereof is added after heating the silkworm slurry. [5] A method for reducing the oxidative odor of silkworm powder, characterized by adding vitamin C or a derivative thereof in the manufacturing process of silkworm powder. [6] A method for reducing the oxidative odor of silkworm powder according to [5], wherein the manufacturing process of silkworm powder includes a step of heating a silkworm slurry obtained by mixing crushed silkworms and water, and vitamin C or a derivative thereof is added to the silkworm slurry. [7] A method for producing silkworm powder, wherein vitamin C or a derivative thereof is added in the manufacturing process of silkworm powder. [8] A method for producing silkworm powder according to [7], wherein the manufacturing process of silkworm powder includes a step of heating a silkworm slurry obtained by mixing crushed silkworms and water, and vitamin C or a derivative thereof is added to the silkworm slurry. [9] Silkworm powder obtained by the manufacturing method according to [8].

[10] A composition containing silkworm powder and vitamin C or a derivative thereof.

[11] A flavor enhancer for silkworm powder comprising vitamin C or a derivative thereof as an active ingredient.

[0008] The present invention makes it possible to reduce the bitterness and oxidative odor of silkworm powder. Furthermore, the composition of the present invention reduces the bitterness of silkworm powder, improves its crispness, shortens the duration of the bitterness, and enhances sweetness, resulting in a good flavor.

[0009] The details of the present invention will be described below. The description of the present invention below may be based on preferred embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, the "~" indicating a numerical range is used to mean that the numbers before and after it are included as the lower limit and upper limit.

[0010] The present invention relates to a method for reducing the bitterness, oxidative odor, and manufacturing method of silkworm powder (hereinafter collectively referred to as "the present invention method"), which involves adding vitamin C or a derivative thereof during the silkworm powder manufacturing process. The method for manufacturing silkworm powder is not particularly limited, and known methods can be used. For example, Japanese Patent Publication No. 08-337530 describes a method in which larvae from the 4th instar to the end of the 5th instar (largest weight silkworm) are treated with nitrogen gas to prevent oxidation, freeze-dried, and then powdered by a pulverizing method, but vitamin C or a derivative thereof can be added in any of these steps. The present invention method preferably includes a step of heating a silkworm slurry obtained by mixing crushed silkworm material with water.

[0011] The silkworm species used as the raw material for silkworm powder are not particularly limited; for example, European, Chinese, or Japanese varieties may be used. Furthermore, the silkworm's developmental stage is not particularly limited; larvae, pupae, or adults may be used, although larvae are preferred.

[0012] The silkworms used as raw material are dried and crushed to obtain crushed material. The drying process is not particularly limited, and known methods such as hot air drying and low-temperature drying can be used. The crushing process is not particularly limited, and can be carried out using known crushing equipment, such as cutter mills, roll mills, hammer mills, ball mills, and bead mills.

[0013] The crushed silkworm material described above is mixed with water to obtain a crushed silkworm slurry. The content of the crushed silkworm material in the crushed silkworm slurry is not particularly limited, but for example, 40 to 95% by mass (hereinafter simply referred to as "%") is preferred, and 70 to 90% is more preferred. The slurry can be prepared using a known stirring and mixing device such as a mixer or kneader.

[0014] In the present invention, vitamin C or a derivative thereof is added to a silkworm crushed material slurry. Examples of vitamin C or its derivatives include ascorbic acid, sodium ascorbate, calcium ascorbate, potassium ascorbate, magnesium ascorbate and other ascorbates, ascorbic acid palmitate, ascorbic acid 2-glucoside, ascorbic acid stearate, and ascorbic acid phosphate. One or more of these may be used individually or in combination. Of these, water-soluble vitamin C derivatives such as ascorbic acid and ascorbates are preferred. Alternatively, raw materials containing vitamin C or its derivatives, such as dried powders of vegetables or fruits, may be used as vitamin C or its derivatives.

[0015] The amount of vitamin C or its derivative added to the crushed silkworm slurry is not particularly limited, but from the viewpoint of reducing the bitterness and oxidative odor of the silkworm powder, for example, 0.01 to 5 parts by mass, more preferably 0.05 to 1 part by mass, and even more preferably 0.1 to 0.5 parts by mass per 100 parts by mass of the crushed silkworm slurry is preferred.

[0016] In the present invention, the silkworm pulverized slurry is heated. Vitamin C or a vitamin C derivative may be added to the silkworm pulverized slurry beforehand and then heated, or vitamin C or a derivative may be added after heating the silkworm pulverized slurry. However, from the viewpoint of reducing bitterness and oxidative odor, it is preferable to add vitamin C or a derivative after heating the silkworm pulverized slurry. The heating conditions are not particularly limited, but 50 to 100°C is preferred, and 70 to 95°C is more preferred. Heat treatment at such temperatures can be carried out for about 10 minutes to 6 hours.

[0017] Silkworm powder can be obtained by drying the heat-treated silkworm crushed slurry and then grinding it. The drying process is not particularly limited and known methods can be used, such as hot air drying, low-temperature drying, and freeze-drying, but freeze-drying is preferred. The grinding process can be carried out using known grinding devices such as cutter mills, roll mills, hammer mills, ball mills, and bead mills.

[0018] The silkworm powder obtained in this way has a reduced bitterness compared to that which does not contain vitamin C or its derivatives. In addition, the production of components that cause oxidative odors, such as hexanal, 3-penten-2one, 2-heptenal, 1-heptanol, and 1-octanol, is suppressed, thereby reducing the oxidative odor.

[0019] Silkworm powder can also be combined with known food additives and / or food ingredients to form food products. Its manufacturing method is not particularly limited and can be prepared according to conventional methods. Its form is also not particularly limited, and examples include protein bars, protein powder, starch-based foods such as bread, biscuits, pancakes, noodles, and candy tablets, confectionery such as gum, candy, and Japanese sweets, meat products such as ham and sausage, fish products such as chikuwa and kamaboko, seafood products, seasonings such as dressings, soy sauce, jam, and furikake, protein drinks, tea, juice, soft drinks, and alcoholic beverages. Among food ingredients, it is preferable to combine it with matcha powder, which can result in food products with excellent flavor. Food products include foods for specified health uses, foods with functional claims, and nutritional supplements.

[0020] It can also be prepared in the form of animal feed or pet food. It is prepared by appropriately blending silkworm powder and flavor enhancers with known feed materials, gelling agents, shape-retaining agents, pH adjusters, seasonings, preservatives, nutritional supplements, etc., according to conventional methods. Its form is not particularly limited, and examples include pellets, flakes, mash, etc. It can be used, for example, as animal feed for livestock such as cattle, pigs, chickens, sheep, and horses, as pet food for dogs and cats, and as aquatic feed for fish and shellfish.

[0021] Furthermore, the above silkworm powder can be formulated in combination with a pharmaceutically acceptable carrier as needed. Examples of pharmaceutically acceptable carriers include glucose, lactose, starch, mannitol, dextrin, fatty acid glycerides, polyethylene glycol, hydroxyethyl starch, ethylene glycol, polyoxyethylene sorbitan fatty acid esters, amino acids, gelatin, albumin, water, and physiological saline. In addition, conventional additives such as stabilizers, wetting agents, emulsifiers, binders, isotonic agents, and excipients can be added as needed. The dosage form is not particularly limited, but examples include liquids, powders, granules, capsules, and tablets, which can be manufactured according to conventional methods.

[0022] As described above, in addition to adding vitamin C or its derivatives during the silkworm powder manufacturing process, the flavor of silkworm powder can also be improved by blending vitamin C or its derivatives into silkworm powder that has been manufactured without adding vitamin C or its derivatives during the process.

[0023] The composition of the present invention contains silkworm powder and vitamin C or a derivative thereof. As described above, the silkworm powder may be one which has been produced by adding vitamin C or a derivative thereof during the manufacturing process, but it may also be one which has been obtained by a conventionally known manufacturing method without adding vitamin C or a derivative thereof. For example, silkworm powder produced by the manufacturing method described in Japanese Patent Publication No. 08-337530 can be used. Examples of commercially available products include MorSilk® Powder (Morus Co., Ltd.). Examples of vitamin C or a derivative thereof include ascorbic acid, sodium ascorbate, calcium ascorbate, potassium ascorbate, magnesium ascorbate and other ascorbates, ascorbic acid palmitate, ascorbic acid 2-glucoside, ascorbic acid stearate, and ascorbic acid phosphate, and may be used alone or in combination of two or more. In addition, raw materials containing vitamin C or a derivative thereof, such as dried powder of vegetables or fruits, may be used as vitamin C or a derivative thereof.

[0024] The content of silkworm powder in the composition of the present invention is not particularly limited, but for example, 97 to 99.9% is preferred, and 98 to 99% is more preferred. The content of vitamin C or its derivative is preferably 0.1 to 5%, and more preferably 0.5 to 2%. As for the content of vitamin C or its derivative relative to silkworm powder, for example, 0.1 to 3 parts by mass is preferred, 0.3 to 2 parts by mass is more preferred, and 0.5 to 1.5 parts by mass is even more preferred, per 100 parts by mass of silkworm powder.

[0025] The composition of the present invention improves the bitterness (sharpness) of silkworm powder, enhances the gyokuro-like sweetness, and has a good flavor. It can be combined with known food additives and / or food ingredients and made into food or beverage form in the same manner as described above.

[0026] The flavor enhancer of the present invention contains vitamin C or a derivative thereof as an active ingredient, and when added to silkworm powder, it improves bitterness (sharpness) and enhances sweetness. The amount of vitamin C or a derivative thereof added to silkworm powder is not particularly limited, but for example, 0.1 to 3 parts by mass is preferred, 0.3 to 2 parts by mass is more preferred, and 0.5 to 1.5 parts by mass is even more preferred, per 100 parts by mass of silkworm powder.

[0027] The present invention will be described in detail below with reference to examples. However, the present invention is not limited to these examples.

[0028] Example 1 [Preparation of Silkworm Powder] Silkworm powder was prepared from samples 1 to 3 by the following method.

[0029] (Sample 1) Silkworm larvae in the fifth instar were crushed using a crushing device to obtain crushed silkworm material. Water was added to the obtained crushed silkworm material to a water content of 10% and mixed to obtain a crushed silkworm slurry. This crushed silkworm slurry was heated to 90-95°C for a total of 90 minutes. Then, it was freeze-dried in a freeze-dryer for 30 hours at a range of 20-90°C, slowly increasing the temperature until the moisture content was 5% or less, and silkworm powder of Sample 1 was obtained using a pulverizer.

[0030] (Sample 2) Sample 2 was prepared in the same manner as Sample 1, except that ascorbic acid was added to the crushed silkworm slurry in advance at a content mass ratio (crushed silkworm:ascorbic acid) of 99.9:0.1 relative to the crushed silkworm in the slurry, and then heat-treated.

[0031] (Sample 3) Sample 3 was prepared in the same manner as Sample 1, except that after heat-treating the crushed silkworm slurry, ascorbic acid was added to the crushed silkworm in the slurry in a mass ratio (crushed silkworm:ascorbic acid) of 99.9:0.1, and then freeze-dried.

[0032] [Sensory Evaluation] Five panelists consumed samples 1-3 and evaluated them on a 5-point scale according to the following evaluation criteria, calculating the average score. The results are shown in Table 1. (Evaluation Criteria) 5: Less bitter than sample 1 4: Slightly less bitter than sample 1 3: Same bitterness as sample 1 2: Slightly stronger bitterness than sample 1 1: Stronger bitterness than sample 1

[0033]

[0034] As shown in Table 1, it was confirmed that adding ascorbic acid to the crushed silkworm slurry reduced the bitterness, and that adding it after heating further reduced the bitterness.

[0035] [Analysis of Aroma Components] The aroma components contained in samples 1 and 3 were analyzed by gas chromatography under the following conditions. The results are shown in Table 2.

[0036] (GC Analysis Conditions) Gas chromatograph: GCMS-TQ8040, Shimadzu Corporation Column: InertCap Pure-WAX (length 30m, inner diameter 0.25mm, film thickness 0.25μm), GL Sciences Co., Ltd. Injection volume: 0.3g Injection method: SPME method Using DVB / CAR / PDMS, 1cm fiber from Spelco Inlet temperature: 250℃ Column temperature: After injection, 50℃ for 5 minutes, then increased to 250℃ at 10℃ per minute, and held at 250℃ for 10 minutes Carrier gas: Helium gas Detector: Mass spectrometer (MS, MS / MS) Detection temperature: 60℃

[0037]

[0038] As shown in Table 2, it was confirmed that adding ascorbic acid to the crushed silkworm slurry suppressed the formation of compounds that cause oxidative odor, thereby reducing the oxidative odor.

[0039] Example 2 [Silkworm Powder Composition] Ascorbic acid was added to silkworm powder (MorSilk® Powder; manufactured by Morus Co., Ltd.) in amounts of 0.3%, 0.5%, and 1% by weight and mixed. Then, water was added to prepare an aqueous solution so that the total concentration of silkworm powder and ascorbic acid was 3%. An aqueous solution of silkworm powder prepared in the same manner without the addition of ascorbic acid was used as a control (score 0). Five panelists evaluated the bitterness (crispness) and gyokuro-like sweetness on a 5-point scale according to the following evaluation criteria, and the average score was calculated. The results are shown in Table 3.

[0040] (Bitterness evaluation criteria) -2: Very sharp compared to control -1: Good compared to control 0: Controlled 1: Poorly sharp compared to control 2: Very poorly sharp compared to control (Sweetness evaluation criteria) -2: Very weak compared to control -1: Weak compared to control 0: Controlled 1: Stronger compared to control 2: Very strong compared to control

[0041]

[0042] As shown in Table 3, it was confirmed that adding vitamin C to silkworm powder reduced bitterness and enhanced the gyokuro-like sweetness, thereby improving the flavor.

Claims

1. A method for reducing the bitterness of silkworm powder, characterized by adding vitamin C or a derivative thereof during the manufacturing process of silkworm powder.

2. The method for reducing the bitterness of silkworm powder according to claim 1, wherein the manufacturing process of silkworm powder includes a step of heating a silkworm slurry obtained by mixing crushed silkworms and water, and is characterized by adding vitamin C or a derivative thereof to the silkworm slurry.

3. The method for reducing the bitterness of silkworm powder according to claim 2, wherein a slurry of crushed silkworms to which vitamin C or a derivative thereof has been added in advance is heated.

4. A method for reducing the bitterness of silkworm powder according to claim 2, wherein vitamin C or a derivative thereof is added after heating the crushed silkworm slurry.

5. A method for reducing the oxidative odor of silkworm powder, characterized by adding vitamin C or a derivative thereof during the manufacturing process of silkworm powder.

6. The method for reducing the oxidative odor of silkworm powder according to claim 5, wherein the manufacturing process of silkworm powder includes a step of heating a silkworm slurry obtained by mixing crushed silkworms and water, and is characterized by adding vitamin C or a derivative thereof to the silkworm slurry.

7. A method for producing silkworm powder, characterized by adding vitamin C or a derivative thereof during the silkworm powder manufacturing process.

8. The method for producing silkworm powder according to claim 7, wherein the silkworm powder production process includes a step of heating a silkworm slurry obtained by mixing silkworm crushing material and water, and is characterized by adding vitamin C or a derivative thereof to the silkworm slurry.

9. Silkworm powder obtained by the manufacturing method described in claim 8.

10. A composition containing silkworm powder and vitamin C or a derivative thereof.

11. A flavor enhancer for silkworm powder containing vitamin C or a derivative thereof as an active ingredient.

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