JP2010075168A - Method for producing onion extract - Google Patents

Abstract

An object of the present invention is to provide a method for producing an onion extract containing a large amount of quercetin glycoside (such as Q-3,4'-O-β- (D-) diglucoside). .
The present invention relates to a crushing step for crushing an onion bulb portion, a squeezing step for obtaining a squeezed juice by squeezing the crushed onion bulb portion, and a squeezed juice obtained in the squeezing step. In the onion extract manufacturing method including a concentration step, a glucosidase deactivation step of deactivating the enzyme glucosidase contained in the onion bulb portion is performed prior to the crushing step. The concentration step is preferably performed at a temperature of 80 ° C. or lower.
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Description

  The present invention relates to a method for producing an onion extract containing a large amount of quercetin glycoside.

  Various useful components are contained in the bulb portion (sphere) of onion, and one of them is quercetin glycoside (Non-patent Document 1).

  In recent studies, quercetin glycosides with sugars rather than quercetin aglycones with broken sugars from the viewpoint of the involvement of quercetin in symptoms such as hypertension, arteriosclerosis, thrombosis, diabetes, and absorption to the human body (Q-3,4'-O-β- (D-) diglucoside, Q-4'-O-β- (D-) glucoside) has been shown to be superior (non-patented) References 2, 3).

  Patent Document 1 describes an extract obtained by concentrating onion bulb juice from about 90 to 60 ° C. However, in this method, the glucosidase in the onion acts during squeezing the onion, and the quercetin glycoside (Q-3,4'-O-β- (D-) diglucoside, Q-4'-O- There was a problem that the sugar of β- (D-) glucoside, Q: quercetin) was hydrolyzed to become quercetin aglycone.

  Patent Document 2 describes that a quercetin glycoside is changed to quercetin aglycone by heat. Patent Document 2 discloses a technique for converting quercetin glycoside into quercetin aglycone with high efficiency. Patent Document 2 describes, as a significance of aglyconization, that quercetin aglycone has superior antioxidant performance in vitro compared to glycosides. However, what is important for the human body is not the antioxidant capacity but the absorption rate. In addition, since quercetin glycosides are aglyconized and absorbed by digestive enzymes in the intestine during absorption into the human body, there is no difference in effects in the human body. Therefore, the present inventor believes that maintaining the quercetin glycoside as a glycoside is more beneficial than aglyconation as in Patent Document 2.

  Patent Document 3 discloses a method for producing onion puree from onion. A method for producing an onion extract containing a large amount of quercetin glycoside is not disclosed.

JP 54-14564 A Japanese Unexamined Patent Publication No. 2007-210916 Japanese Patent No. 3993804 Kinoshita et al., Fruit Juice Association Bulletin, No.595, 14-25 (2008) Peter CH Hollman etc, Am J Clin Nutr 1995: 62: 1276-1282 Terao, Vitamins, 79, 1 (2005)

  No technology has been provided in the past to increase the concentration of quercetin glycosides in onions as they are without aglyconization.

  The present invention produces an onion extract containing a large amount of quercetin glycoside (Q-3,4'-O-β- (D-) diglucoside, Q-4'-O-β- (D-) glucoside). It aims to provide a method for

  The present inventors have found that aglyconization of quercetin glycoside occurs when crushing onion, and that aglyconization of quercetin glycoside is remarkably suppressed by crushing after inactivating glucosidase. . Conventionally, the relationship between glucosidase activity in onions and aglyconization of quercetin glycosides has not been known.

The present invention includes the following inventions.
(1) A crushing step of crushing an onion bulb portion, a squeezing step of squeezing the crushed onion bulb portion to obtain a squeezed solution, and a concentration step of concentrating the squeezed solution obtained in the squeezing step In the production method of the onion extract containing,
Prior to the crushing step, a method for producing an onion extract comprising a glucosidase deactivation step of deactivating the enzyme glucosidase contained in the onion bulb portion.

(2) The method for producing an onion extract according to (1), wherein the concentration step is a step of concentrating the juice at a temperature of 80 ° C. or lower.

(3) The glucosidase deactivation step is a step of deactivating glucosidase by heating the onion bulb part,
The heating time of the central part of the onion bulb part and the temperature at the time of heating are X (unit: minutes) as the shortest heating time of the central part of the onion bulb part, and the temperature of the central part of the onion bulb part is Y ( (Unit: ° C)
Y ≧ 0.01426003 × X ² -1.480861 × X + 98.37368
The method for producing an onion extract according to (1) or (2), wherein

(4) Onion extract containing 3.0 mg or more of Q-3,4'-O-β- (D-) diglycoside per 1 g of soluble solid content.

(5) A processed food or drink containing the onion extract according to (4), or a processed food or drink containing the onion extract produced by the method according to any one of (1) to (3).

  According to the present invention, an onion extract containing a high content of quercetin glycoside, particularly Q-3,4'-O-β- (D-) diglycoside can be produced.

1. Onion The onion used in the present invention is not limited in variety, and it does not matter whether it is peeled or not. Moreover, if the conversion rate of the contained quercetin glycoside to quercetin aglycone is 5% or less, an onion cut into an arbitrary size and shape can be used.

  The onion bulb refers to the part of the sphere that is normally edible. In this specification, unless otherwise specified, “onion” refers to “onion bulb”.

2. Quercetin glycosides contained in quercetin onions include Q-3,4'-O-β- (D-) diglucoside, Q-4'-O-β- (D-) glucoside ( Q: Quercetin) is a typical example.

3. Glucosidase deactivation step One of the features of the present invention is that the enzyme glucosidase contained in the onion is deactivated before the onion is crushed.

  The onion used in this step may be cut into any size and shape as long as the conversion rate of the contained quercetin glycoside to quercetin aglycone is 5% or less. For example, the whole onion or onion cut into a size of 1/2 to 1/8 can be used.

  Examples of the method for inactivating glucosidase include protein denaturation by heating. Heating methods include microwave heating, boiling, steaming, and the like.

  For example, heating with a microwave oven is done for 7.5 to 10 minutes in a 500 W microwave oven for one peeled onion (about 300 g). An onion appropriately cut as described above can also be used.

  For example, heating by boiling is performed by adding 1 onion (about 300 g) to 800 g of boiling water and heating for 15 to 60 minutes. An onion appropriately cut as described above can also be used.

  For heating by steaming, for example, a suitable amount of water is placed in a commercially available steamer and heated, and then one onion (about 300 g) is added to the generated steam and heated for 15 to 60 minutes. An onion appropriately cut as described above can also be used.

The heating time and temperature of the central part of the onion sample in the heating inactivation process are X (unit: minutes) as the shortest heating time of the central part of the onion sample, and the temperature of the central part of the onion bulb during heating is Y ( Unit: ° C), (X, Y) = (50, 60), (X, Y) = (25, 75), (X, Y) = (15, 80), (X, Y) When an approximate curve drawn based on five points of (Y) = (5, 90) and (X, Y) = (3, 95) is expressed by the equation of Y = F (X), the equation Y ≧ F (X ) Is preferably satisfied. Glucosidase is sufficiently inactivated within the range of this condition. Since the quadratic approximation by the least square method based on the above five points is Y = 0.01426003 × X ² -1.480861 × X + 98.37368, X and Y satisfy Y ≧ 0.01426003 × X ² -1.480861 × X + 98.37368 Is particularly preferred. The range of X (min) to which this approximate expression is applied is preferably 1 to 60, particularly preferably 3 to 52, and most preferably 3 to 50.

  The heating time of the onion sample in the heat deactivation step is not particularly limited as long as it is a time equal to or more than X that satisfies the above relationship, but is preferably within 120 minutes from the viewpoint of production efficiency.

4. Crushing process The crushing process is a process in which the onion after the glucosidase deactivation process is crushed by crushing or squeezing it using a mixer, a comitoroll, a micromeister, a press, or the like. In order to elute the quercetin glycoside from the inside of the cell, it is preferable to perform crushing with a solvent such as water and a 0-80% ethanol solution.

5. Squeezing process Onion crushed material consists of liquid components from which quercetin glycosides are eluted and solid components such as cell walls. In the squeeze process, the liquid component is separated from the crushed material. The solid-liquid separation can be performed by a usual method such as centrifugation or filtration (for example, diatomaceous earth filtration). In addition, a squeezing process can also be performed simultaneously with a crushing process, such as pressing.

6. Concentration process The concentration process is a process of concentrating the juice obtained in the juice extraction process. Concentration here refers to reducing the water content in the juice to a final sugar concentration of 50% or more. The sugar concentration can be measured with a commercially available saccharimeter.

  Concentration is preferably performed at a temperature of 80 ° C. or lower. When the juice or concentrate is exposed to a temperature exceeding 80 ° C., aglyconization of the contained quercetin glycoside proceeds significantly.

  More preferably, the juice is concentrated so that the pH of the juice or concentrate is in the range of 5.5 to 7.5. When the pH is less than 5.5, the quercetin glycoside is easily converted to quercetin aglycone. In addition, when the pH is more alkaline than 7.5, the quercetin skeleton itself is broken and the quercetin itself tends to be decomposed.

As the concentration method, for example, vacuum evaporation concentration or membrane concentration can be employed.
Vacuum evaporation concentration is generally called vacuum concentration. The degree of vacuum at the time of concentration can be selected as long as the final product can have a sugar content of 50% or more, and is not particularly limited.

  Membrane concentration can be performed using a membrane such as a reverse osmosis membrane (RO) or an ultrafiltration membrane (UF). The type of membrane to be used can be selected within a range where the sugar content can be 50% or more, and is not particularly limited.

7. Onion extract and use thereof The onion extract produced by the method of the present invention contains a high concentration of quercetin glycoside. Q-3,44′-O-β- (D-) diglycoside, which is a typical quercetin glycoside, is contained in an onion extract in an amount of 3.0 mg or more, more preferably 3.5 mg or more per 1 g of soluble solid content. The

  The quercetin glycoside-rich onion extract can be used in various forms as a component of processed foods and drinks that promote health promotion. Specific processed foods and drinks include, for example, supplements such as soft capsules, seasoned foods such as curry and stew and soup containing the extract, beverages containing the extract, and onion vinegar obtained by further fermenting the extract. It is done.

Analysis method of quercetin glycosides The analysis method of quercetin glycosides (Q-3,4'-O-β- (D-) diglucoside, Q-4'-O-β- (D-) glucoside) and quercetin aglycone is It was as follows. All subsequent analysis was performed by this method. In the pretreatment, the sample is diluted with a 2% acetic acid 50% methanol solution so that the quercetin concentration is 0.001 to 0.01 mg / ml, filtered through a 0.45 μm filter, and then subjected to liquid chromatography analysis under the following conditions. I did it.
Condition: Column: ODS analytical column (PEGASIL ODS 4.6Φ x 250mm, manufactured by Senshu Pak)
Liquid chromatograph: Hitachi D-7000 HPLC system Flow rate: 1.0ml / min
Detector: UV360nm
Mobile phase: 2% acetic acid 10% methanol solution → 2% acetic acid 80% methanol solution / 20 min
2% acetic acid 80% methanol solution / 5 min Injection volume: 10 μl

Conversion of quercetin glycoside to quercetin aglycone by heating
A sample of Q-3,4'-O-β- (D-) diglucoside (manufactured by polyphenols) was adjusted to 0.05 mg / ml with distilled water, and each was 60 ° C, 80 ° C, and 95 ° C. The mixture was allowed to stand for minutes, and the residual ratio of Q-3,4′-O-β- (D-) diglucoside was measured using the above method. The pH of the solution at that time was 6.5.

  The results are shown in Figure 1. There was almost no change in the error range up to 80 ° C, but a decrease of about 4% was seen at 95 ° C. At the same time, production of Q-4'-O-β- (D-) glucoside and quercetin aglycone was observed, indicating that the glycoside sugar was cut at 95 ° C.

Conversion of quercetin glycoside to quercetin aglycone by pH
Q-3,4'-O-β- (D-) diglucoside preparation (polyphenols), Q-4'-O-β- (D-) glucoside preparation (polyphenols), quercetin aglycone (Quercetin dihydrate, manufactured by Wako) was adjusted to 0.05 mg / ml using a 50% ethanol solution, and it was adjusted to pH 2.5, 4.0, 6. using citric acid and sodium bicarbonate. It adjusted to 5, 8.0 and left still at 25 degreeC for 3 days.

  The result is shown in figure 2. A decrease in quercetin glycosides is observed in the acidic range. At the same time, production of Q-4′-O-β- (D-) glucoside and quercetin aglycone was observed, indicating that the sugars of glycosides were cut off in the acidic range of pH 4.0 or lower. In the alkaline region, there is a significant decrease including quercetin aglycone. In HPLC, the wavelength intensity itself at 360 nm decreased, and production of other quercetins was not observed. Therefore, it is considered that the quercetin skeleton itself was decomposed or changed.

Conversion of quercetin glycoside to quercetin aglycone by combination of heating and pH
A sample of Q-3,4'-O-β- (D-) diglucoside (manufactured by polyphenols) was adjusted to 0.05 mg / ml with distilled water and adjusted to pH 2.5 with citric acid. . It was allowed to stand at 60 ° C., 80 ° C., and 95 ° C. for 60 minutes, respectively, and the residual ratio of Q-3,4′-O-β- (D-) diglucoside was measured using the above method.

  The results are shown in Figure 3. Conversion to quercetin aglycone tended to be accelerated by heating and pH.

Effect of glucosidase during onion processing A commercially available onion (North Maple 2000) was peeled and cut 1/4 with a knife equally when viewed from above. The weight at that time was 343 g. The 1/4 cut was immediately put into 600 g of hot water that had been adjusted to 95 ° C in advance, and allowed to stand for 15 minutes while adjusting to 95 ° C. This was crushed together with hot water using a home mixer (MX-X107 National). The crushed solution was centrifuged using a centrifuge (himac CR21 manufactured by Hitachi, rotor: RPR9-2) under the conditions of 4 ° C., 8000 rpm, and 15 min. 864 g of the supernatant was obtained. This was divided into equal parts and designated as supernatant 1 and supernatant 2, respectively. The supernatant 1 was concentrated to a sugar content of 70% at 80 ° C. and 100 hPa using an evaporator (VAPOR TRAPUNIT DPE-2000, NEWROTARY VACUUM EVAPORATOR NE) manufactured by EEYLA. The sugar content was measured with a sugar meter (Refractometer RX-7000α) manufactured by ATAGO. This final product is designated as Example 1. Supernatant 2 was heated and concentrated in a 500 ml glass beaker until the sugar content reached 70%. The relationship between sugar content and boiling point temperature at this time was as follows. This final product is designated as Example 2.

市販のタマネギ（北もみじ２０００）1個を皮をむいて上から見て等分に包丁で1/4カットした。その時の重量は３５４ｇだった。これに蒸留水６００ｇを加え、家庭用ミキサー（MX-X107 National製）で破砕した。破砕した溶液を遠心分離機（himac CR21 日立製、ローター：RPR9-2）を用いて4℃、8000rpm、15minの条件で遠心分離をした。その上澄み液は８２８ｇ得られた。これを等分に分け、それぞれ上澄み液3、上澄み液4とした。上澄み液3はEYELA社製エバポレーター（VAPOR TRAPUNIT DPE-2000、NEWROTARY VACUUM EVAPORATOR NE）を用いて80℃100hPaで糖度70%まで濃縮した。糖度はATAGO社製糖度計（Refractometer RX-7000α）で測定した。この最終品は比較例１とする。上澄み液4は500mlのガラス製ビーカーで糖度70%になるまで、加熱し沸騰濃縮した。この最終品は比較例２とする。

A commercially available onion (North Maple 2000) was peeled and cut 1/4 with a knife equally when viewed from above. The weight at that time was 354 g. Distilled water (600 g) was added thereto, and the mixture was crushed with a home mixer (manufactured by MX-X107 National). The crushed solution was centrifuged using a centrifuge (himac CR21 manufactured by Hitachi, rotor: RPR9-2) under the conditions of 4 ° C., 8000 rpm, and 15 min. 828 g of the supernatant was obtained. This was divided into equal parts and designated as Supernatant 3 and Supernatant 4, respectively. Supernatant 3 was concentrated to a sugar content of 70% at 80 ° C. and 100 hPa using an evaporator (VAPOR TRAPUNIT DPE-2000, NEWROTARY VACUUM EVAPORATOR NE) manufactured by EEYLA. The sugar content was measured with a sugar meter (Refractometer RX-7000α) manufactured by ATAGO. This final product is referred to as Comparative Example 1. Supernatant 4 was heated and concentrated in a 500 ml glass beaker until the sugar content reached 70%. This final product is referred to as Comparative Example 2.

  The amount of quercetin glycoside and quercetin aglycone of Example 1, Example 2, Comparative Example 1 and Comparative Example 2 was measured according to the above measurement method, and converted into the amount per 1 g of soluble solid content in the concentrated onion extract. Compared. The pH of the final product was almost the same as Example 1: 6.2, Example 2: 6.2, Comparative Example 1: 6.1, and Comparative Example 2: 6.2.

  The results are shown in FIG. Aglyconization of quercetin glycosides by glucosidase during the first processing of onions and aglyconization by heating during concentration were markedly observed. The reason why aglyconization by heating at the time of concentration has progressed more than in the above experiment is thought to be that the boiling point temperature increased due to the rise in molar boiling point caused by the increase in sugar content, and a higher temperature was applied.

Crude purification of glucosidase From the above results, it was estimated that aglyconization of the quercetin glycoside during onion crushing was due to glucosidase, but in order to make it more reliable, purification of glucosidase was attempted. Glucosidase activity was adjusted to 0.05 mg / ml with Q-3,4'-O-β- (D-) diglucoside preparation (polyphenols) using distilled water, and in addition to Q-4'- Whether or not O-β- (D-) glucoside, Q-3′-O-β- (D-) glucoside and quercetin aglycone were produced was measured and confirmed. A commercially available onion (North Maple 2000) was peeled and cut 1/4 with a knife equally when viewed from above. The weight at that time was 378 g. Distilled water (600 g) was added thereto, and the mixture was crushed with a home mixer (manufactured by MX-X107 National). The crushed solution was centrifuged using a centrifuge (himac CR21 manufactured by Hitachi, rotor: RPR9-2) under the conditions of 4 ° C., 8000 rpm, and 15 min. 1 g of this supernatant and the residue was added to 5 g of the above preparation to confirm the activity, and it was confirmed that the residue was active. The residue was treated with a homogenizer (PolytronPT2100, shaft: PT2120, manufactured by KINEMATICA) (room temperature 10000 rpm) to completely crush the cell wall by adding 500 g of distilled water. When 1 g of this was added to 5 g of the above preparation and the activity was confirmed, the activity was present. From this, it is considered that glucosidase related to the present invention is highly likely to be a membrane protein in the cell membrane. The crushed product was centrifuged using a centrifuge (himac CR21 manufactured by Hitachi, rotor: RPR9-2) under the conditions of 4 ° C., 8000 rpm, and 15 min to obtain 473 g of a supernatant. 100 ml of a 100% ethanol solution cooled to 4 ° C. was added to 50 g of this supernatant and allowed to stand at 4 ° C. for 3 hours for organic solvent precipitation. This solution is centrifuged using a centrifuge (himac CR21, manufactured by Hitachi, rotor: RPR9-2) at 4 ° C, 8000 rpm, 15 min, the supernatant is discarded, and 20% glycerin is added to the resulting residue. It melt | dissolved with the solution (made by WAKO). This is hereinafter referred to as a glucosidase solution. 100 μl of glucosidase solution is prepared from Q-3,4'-O-β- (D-) diglucoside (polyphenols), Q-4'-O-β- (D-) glucoside (polyphenols) ), Q-3'-O-β- (D-) glucoside preparation (isoquercitrin manufactured by Kanto Chemical Co., Inc.), each of which was added to a solution adjusted to 0.05 mg / ml using distilled water, and the activity was confirmed. did.

  The results are shown in FIG. The left side of FIG. 5 is the analysis result of each sample before the treatment with the glucosidase solution, and the right side is the analysis result of each sample after the treatment with the glucosidase solution. Activity was observed in each, and it was confirmed that glucosidase was present. Since it reacts with the glucosides at the 3rd and 4th positions of the quercetin glycoside, the glucosidase solution may contain a plurality of glucosidases.

Search for Inactivation Conditions of Glucosidase The inactivation conditions by heating were searched using the above glucosidase solution. Dispense 1 ml of glucosidase solution into a 2 ml microtube, incubate at 60 ° C, 70 ° C, 80 ° C, 90 ° C, 95 ° C for a specified time in a constant temperature water bath (C-650 manufactured by Taiyo Chemical Co., Ltd.). Add 100 μl of glucosidase solution to 1 ml of Q-3,4'-O-β- (D-) diglucoside preparation (polyphenols) adjusted to 0.05 mg / ml with distilled water, The presence or absence of activity was confirmed from the residual rate (%) of Q-3,4′-O-β- (D-) diglucoside after standing at 24 ° C. for 24 hours. That is, when the residual rate (%) of Q-3,4'-O-β- (D-) diglucoside is 100%, the residual rate of glucosidase activity is 0%, and Q-3,4'-O-β- When the residual rate (%) of (D-) diglucoside was 50%, the residual rate of glucosidase activity was 50%, and the presence or absence of activity was confirmed. The results are shown in Table 2.

  The incubation temperature and time required for the residual rate of glucosidase activity to be 0.5% or less, derived from the results shown in Table 2, are indicated by the area on the line shown in FIG.

The heat stability of Q-3,4'-O-β- (D-) diglucoside under the conditions of pH 6.5 is shown. The relationship between the change of pH and the stability of quercetin is shown. The heat stability of Q-3,4'-O-β- (D-) diglucoside under the condition of pH2.5 is shown. The relationship between a processing method and the amount of quercetin in an onion extract is shown. A crude glucosidase product isolated from onion was prepared by preparing a preparation of Q-3,4'-O-β- (D-) diglucoside, a preparation of Q-4'-O-β- (D-) glucoside, and Q The result made to act on the sample of -3'-O- (beta)-(D-) glucoside is shown. The time and temperature required to inactivate glucosidase are indicated.

Claims (5)

An onion extract comprising a crushing step for crushing an onion bulb portion, a squeezing step for squeezing the crushed onion bulb portion to obtain a squeezed juice, and a concentration step for concentrating the squeezed juice obtained in the squeezing step In the manufacturing method of
Prior to the crushing step, a method for producing an onion extract comprising a glucosidase deactivation step of deactivating the enzyme glucosidase contained in the onion bulb portion.   The manufacturing method of the onion extract of Claim 1 whose said concentration process is a process of concentrating the said squeezed liquid at the temperature of 80 degrees C or less. The glucosidase deactivation step is a step of deactivating glucosidase by heating the onion bulb part,
The heating time of the central part of the onion bulb part and the temperature at the time of heating are X (unit: minutes) as the shortest heating time of the central part of the onion bulb part, and the temperature of the central part of the onion bulb part is Y ( (Unit: ° C)
Y ≧ 0.01426003 × X ² -1.480861 × X + 98.37368
The manufacturing method of the onion extract of Claim 1 or 2 which satisfy | fills.   An onion extract containing 3.0 mg or more of Q-3,4'-O-β- (D-) diglycoside per 1 g of soluble solid content.   Processed food / beverage products containing the onion extract of Claim 4, or processed food / beverage products containing the onion extract manufactured by the method of any one of Claims 1-3.

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