Anthocyanin-containing beverages

Abstract

In beverages containing anthocyanins, this method suppresses the photodegradation of anthocyanins. [Solution] Copper ions are added to a beverage containing anthocyanins, and the ratio of copper ion content (B: ppm) to anthocyanin content (A: ppm) (B / A) is adjusted to 0.000003 or higher.

Description

Technical Field

[0001] The present invention relates to a beverage containing anthocyanin, a method for producing the same, a method for suppressing the decomposition of anthocyanin, and the like.

Background Art

[0002] Anthocyanin is a pigment widely present in the plant kingdom and has long been used as a coloring agent in foods. In recent years, it has attracted attention as a component having functions other than coloring, such as an antioxidant effect, an effect of reducing eye fatigue, an effect of improving night vision, an effect of improving peripheral blood flow, and an effect of suppressing body fat accumulation.

[0003] On the other hand, anthocyanin is generally inferior in light resistance and is known to fade by photodegradation (Patent Document 1). Regarding this point, it has been reported that the discoloration of chlorophyll can be suppressed by adjusting the content ratio of copper ions and zinc ions in a beverage containing chlorophyll (Patent Document 2). Also, in the production of green juice beverages, it has been reported that the bright green color of green juice beverages can be maintained by adding metal ions, adjusting the pH to a certain range, and then sterilizing (Patent Document 3). However, while anthocyanin is a type of polyphenol, chlorophyll has a structure in which phytol (long-chain alcohol) is ester-bonded to tetrapyrrole, and the chemical structures of the two are completely different. Therefore, the findings obtained for chlorophyll cannot be applied to anthocyanin.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Disclosure of the Invention

[0005] The object of the present invention is to suppress the photodegradation of anthocyanins in beverages containing anthocyanins. [Means for solving the problem]

[0006] To solve the above problems, the inventors conducted diligent research using various metal ions and found that by adding copper ions to a beverage containing anthocyanins and adjusting the ratio of copper ion content (B:ppm) to anthocyanin content (A:ppm) to 0.000003 or higher (B / A), the photodegradation of anthocyanins can be suppressed. Furthermore, they found that the photodegradation-suppressing effect of anthocyanins can be further improved by adjusting the anthocyanin content and copper ion content to a predetermined range.

[0007] In other words, the present invention relates to, but is not limited to, the following. (1) A beverage containing anthocyanins and copper ions, The beverage wherein the ratio of copper ion content (B: ppm) to anthocyanin content (A: ppm) (B / A) is 0.000003 or more. (2) The beverage described in (1), having a copper ion content of 0.001 to 1 ppm. (3) The beverage described in (1) or (2), having an anthocyanin content of 0.25 to 300 ppm. (4) A beverage described in any of (1) to (3) with a pH of 6 or less. (5) A beverage as described in any of (1) to (4), which contains copper ions as copper salts or copper yeast. (6) The beverage according to (5), wherein the copper salts are copper sulfate or copper gluconate. (7) A beverage in a clear container, as described in any of (1) to (6). (8) A method for producing a beverage containing anthocyanins, The process includes adding anthocyanins and copper ions to the beverage. The method wherein the ratio (B / A) of the copper ion content (B: ppm) to the anthocyanin content (A: ppm) in the beverage is 0.000003 or more. (9) A method for suppressing the decomposition of anthocyanins in beverages, The process includes adding anthocyanins and copper ions to the beverage. The method wherein the ratio (B / A) of the copper ion content (B: ppm) to the anthocyanin content (A: ppm) in the beverage is 0.000003 or more. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a beverage containing anthocyanins in which the photodegradation of anthocyanins is suppressed. In other words, the present invention makes it possible to provide a beverage in which anthocyanins are stably retained for a long period of time. [Modes for carrying out the invention]

[0009] Unless otherwise specified, "ppm" as used herein refers to ppm in weight / volume (w / v).

[0010] 1. Beverages containing anthocyanins In one embodiment, the present invention relates to a beverage containing anthocyanins and copper ions, wherein the ratio of the copper ion content (B: ppm) to the anthocyanin content (A: ppm) (B / A) is 0.000003 or more. By adding copper ions to a beverage containing anthocyanins and adjusting the ratio of the copper ion content (B: ppm) to the anthocyanin content (A: ppm) (B / A) to 0.000003 or more, the photodegradation of anthocyanins can be suppressed.

[0011] (1) Anthocyanins Anthocyanins are a type of polyphenol and are natural pigments found in abundance in grapes, blueberries, blackcurrants, eggplants, purple sweet potatoes, black beans, and red wine. While anthocyanins have long been used to color food, in recent years they have attracted attention for their antioxidant, eye strain-reducing, night vision-improving, peripheral blood flow-improving, and body fat accumulation-inhibiting effects. Anthocyanins are a general term for glycosides in which sugars are bonded to the aglycone, anthocyanidin. Six types of anthocyanidins are primarily known: delphinidin, cyanidin, malvidin, peonidin, petunidin, and pelargonidin. In plants, the majority exist as glycosides (anthocyanins). The bonded sugars are mainly monosaccharides such as glucose, galactose, arabinose, rhamnose, and xylose, but disaccharide and trisaccharide combinations also exist. Furthermore, acylated anthocyanins also exist in which one or more organic acids are ester-bonded to the sugar portion. Examples of organic acids include aliphatic organic acids (such as acetic acid and malonic acid) and aromatic organic acids (such as p-coumaric acid, caffeic acid, and ferulic acid). In this specification, "anthocyanin" is a general term for the various anthocyanins mentioned above, and refers to substances containing some or all of the anthocyanins.

[0012] The upper limit of the anthocyanin content in the beverage of the present invention is not particularly limited, but for example, it could be 300 ppm, 250 ppm, 200 ppm, 150 ppm, 100 ppm, 75 ppm, 50 ppm, or 30 ppm. The lower limit of the anthocyanin content in the beverage of the present invention is not particularly limited, but for example, it could be 0.25 ppm, 0.5 ppm, 0.75 ppm, 1 ppm, 2 ppm, or 3 ppm. Furthermore, the range of anthocyanin content in the beverage of the present invention is not particularly limited, but for example, it could be 0.25 to 300 ppm, 0.5 to 250 ppm, 0.75 to 200 ppm, 1 to 150 ppm, 2 to 100 ppm, 3 to 75 ppm, 3 to 50 ppm, or 4 to 30 ppm. By setting the content within this range, the photodegradation inhibitory effect of anthocyanins can be further improved by incorporating a certain amount of copper ions.

[0013] When producing the beverage of the present invention, purified or isolated anthocyanins may be used, raw materials containing anthocyanins may be used, or both may be used. Examples of raw materials containing anthocyanins include plant extracts such as grapes, blueberries, blackcurrants, eggplants, purple sweet potatoes, black beans, and purple carrots, as well as red wine. When using such raw materials in the present invention, they may be used individually or in combination of two or more.

[0014] The anthocyanin content can be measured by methods such as HPLC, LC-MS, LC-MS / MS, absorbance, and pH differential (AOAC 2005.02. 2005. Horwitz W. ed., Official Methods of Analysis of AOAC International, 18th Ed. AOAC Int., Gaithersburg, MD), but measurement by HPLC is preferred. For example, the anthocyanin content can be determined by measuring the total amount of anthocyanins using cyanidin-3-glucoside as an indicator, according to the method of Cassinese et al. (Journal of AOAC International Vol.90, No.4, 911-919, 2007). In this example, the total area at 525 nm obtained by HPLC was calculated as the equivalent amount of cyanidin-3-glucoside. That is, in this invention, the anthocyanin content refers to the measured value using cyanidin-3-glucoside as an indicator.

[0015] (2) Copper ions The upper limit of the content of copper ions contained in the beverage of the present invention is not particularly limited, and for example, it is 10 ppm, 5 ppm, 1 ppm, 0.5 ppm, or 0.25 ppm. Also, the lower limit of the content of anthocyanins contained in the beverage of the present invention is not particularly limited, and for example, it is 0.001 ppm, 0.0025 ppm, 0.005 ppm, 0.01 ppm, 0.015 ppm, or 0.025 ppm. Furthermore, the content range of anthocyanins contained in the beverage of the present invention is not particularly limited, and for example, it is 0.001 - 10 ppm, 0.0025 - 5 ppm, 0.01 - 1 ppm, 0.015 - 0.5 ppm, or 0.015 - 0.25 ppm. By setting the content within this range, the effect of suppressing the photodegradation of anthocyanins can be further improved.

[0016] When manufacturing the beverage of the present invention, the copper ions can be derived from the raw materials containing anthocyanins or can be those added separately. In order to adjust the content of copper ions within the above range, copper salts or copper yeast that can be incorporated into the beverage can be added. Examples of copper salts include copper sulfate, copper gluconate, etc. Also, examples of copper yeast include yeast that has incorporated copper, etc. In one aspect, the copper ions in the beverage of the present invention are derived from copper salts or copper yeast. Also, in the beverage of the present invention, the copper ions may exist in a free state or a non - free state from copper salts or copper yeast.

[0017] The method for measuring the content of copper ions is not particularly limited, and known measurement methods can be used. For example, the content of copper ions can be measured using a colorimetric method.

[0018] In the beverage of the present invention, metal ions other than copper ions (for example, iron ions, zinc ions, manganese ions, calcium ions, magnesium ions, etc.) may be blended as long as they do not inhibit the effect of suppressing the photodegradation of anthocyanins by copper ions.

[0019] (3) The ratio of copper ion content (B: ppm) to anthocyanin content (A: ppm) (B / A) In the beverage of the present invention, the ratio of copper ion content (B: ppm) to anthocyanin content (A: ppm) (B / A) is 0.000003 or higher. The upper limit of this ratio is not particularly limited, but for example, it could be 1.0, 0.5, 0.35, 0.15, 0.035, or 0.015. The lower limit of this ratio is not particularly limited, but for example, it could be 0.000008, 0.00001, 0.00003, 0.00008, 0.0001, 0.0003, 0.0008, 0.001, or 0.003. Furthermore, the range of this ratio is not particularly limited, but for example, it could be 0.000003 to 1.0, 0.000008 to 0.5, 0.00001 to 0.35, 0.00003 to 0.15, 0.00008 to 0.035, or 0.0001 to 0.015. By setting the ratio within this range, the photodegradation inhibitory effect of anthocyanins can be achieved.

[0020] (4) pH The pH of the beverage of the present invention is not particularly limited, but is, for example, pH 2.0 to 7.0, and preferably 3.0 to 6.0. When the pH of the beverage of the present invention is 3.0 to 6.0, the effect of copper ions in suppressing the photodegradation of anthocyanins can be further improved.

[0021] The pH adjustment of the beverage of the present invention is not particularly limited, but for example, organic acids such as citric acid, malic acid, lactic acid, and phosphoric acid; sodium salts such as disodium citrate, trisodium citrate, sodium bicarbonate, and sodium hydroxide; and potassium salts such as potassium hydroxide and potassium carbonate can be used.

[0022] (5) Types of beverages The type of beverage in the present invention is not particularly limited and may be an alcoholic beverage or a non-alcoholic beverage such as a soft drink. In this specification, an alcoholic beverage means a beverage with an alcohol content of 1 v / v% or more, while a non-alcoholic beverage means a beverage with an alcohol content of less than 1 v / v%. In this specification, there are no particular limitations on the type of alcoholic beverage, but examples include spirits, liqueurs, shochu, gin, vodka, rum, highballs, chuhai (shochu cocktails), cocktails, and sours. In addition, alcoholic beverages in this specification may be carbonated or non-carbonated beverages. Furthermore, in this specification, there are no particular limitations on the alcohol content of alcoholic beverages, but examples include 3-40 v / v%, 5-35 v / v%, and 10-30 v / v%.

[0023] In this specification, non-alcoholic beverages include, but are not limited to, functional beverages, nutritional beverages, soft drinks, flavored water (near-water) beverages, sports drinks, tea beverages (grain tea, green tea, oolong tea, black tea, blended tea, etc.), coffee beverages, and carbonated beverages.

[0024] (6) Container In one embodiment, the beverage of the present invention is a packaged beverage. The type of container used is not limited, but a transparent container is preferred. Beverages filled in transparent containers are susceptible to the effects of light irradiation. Examples of transparent containers include those with a transmittance of 40% or more, preferably 50% or more, at 700 nm of visible light. Specifically, transparent plastic bottles and transparent glass bottles can be exemplified, and transparent PET bottles are particularly suitable for use in the present invention. The color of the container is not particularly limited, but it is preferred to be colorless.

[0025] Furthermore, a transparent container may be partially or entirely covered with film or the like. For example, the transparent area is not limited to containers where the label or printed area for content indication is opaque or semi-transparent and the rest is transparent, or containers where transparent and opaque areas with design elements are combined in different ways in multiple places, or opaque containers that only have a transparent area the size of a viewing window.

[0026] (7) Other ingredients The beverage of the present invention may contain various additives, such as flavorings, vitamins, colorants, antioxidants, emulsifiers, preservatives, seasonings, extracts, pH adjusters, and quality stabilizers, in the same manner as ordinary beverages, as long as they do not interfere with the effects of the present invention.

[0027] (8) Heat sterilization In one embodiment, the beverage of the present invention may be a sealed, bottled beverage obtained through heat sterilization. The heat sterilization conditions can be selected to obtain an effect equivalent to that stipulated in the Food Sanitation Act, for example, and can be 60 to 150°C for 1 second to 60 minutes. When using a heat-resistant container (such as glass), retort sterilization (110 to 140°C, 1 to several tens of minutes) can also be performed. Alternatively, when using a non-heat-resistant container (such as a PET bottle), the prepared liquid can be pre-sterilized at high temperature for a short time using a plate heat exchanger or the like (UHT sterilization: 110 to 150°C, 1 to several tens of seconds), cooled to a certain temperature, and then filled into the container.

[0028] 2. Method In one embodiment, the present invention relates to a method for producing a beverage containing anthocyanins. Specifically, the method includes the step of blending anthocyanins and copper ions into a beverage, wherein the ratio of the copper ion content (B: ppm) to the anthocyanin content (A: ppm) in the beverage (B / A) is 0.000003 or more.

[0029] The steps for adjusting the content of the above components in the beverage and the pH of the beverage are as described above or obvious from them with respect to the beverage of the present invention. The timing is also not limited. For example, the above steps may be performed simultaneously, separately, or in any order. It is sufficient that the final beverage obtained satisfies the above conditions. Furthermore, the preferred ranges for the content of the above components, the above ratios, and the pH are as described above with respect to the beverage. Furthermore, the types of beverages produced by the above method are also as described above with respect to the beverage.

[0030] The beverage produced by the manufacturing method of the present invention can suppress the photodegradation of anthocyanins. Therefore, in another respect, this manufacturing method is a method for suppressing the photodegradation of anthocyanins. [Examples]

[0031] The details of the present invention will be specifically described below with reference to experimental examples, but the present invention is not limited thereto. Furthermore, unless otherwise specified in this specification, numerical ranges are described as including their endpoints.

[0032] In this example, the anthocyanin content in the beverage was measured using HPLC. The specific measurement method is as follows. • HPLC system: Thermo Vanquish UHPLC system • Column: Impact UK-C18 HT (3mm x 100mm) Column temperature: 40°C Mobile phase A: Water-formic acid (99.9:0.1) Mobile phase B: Acetonitrile-formic acid (99.9:0.1) • Detection: UV525nm ·Injection volume: 5μL ·Flow rate: 1.0mL / min • Gradient Program: Time (minutes) %A %B 0 94 6 0.5 94 6 4.5 72 28 5.0 0 100 6.0 0 100 6.1 94 6 7.0 94 6 • Standard material: Cyanidin 3-glucoside chloride (Nagara Science)

[0033] Example 1: Comparison of various metal ions' effects on inhibiting anthocyanin degradation A sample beverage containing 9 ppm of anthocyanins (pH 3.3, 20% ethanol) was prepared, and various metal ions (iron ions, zinc ions, or copper ions) were added in the salt form and concentration shown in Table 1, adjusting the total volume to 200 μL. The samples were then irradiated with light (42 kilolux, 25°C, 24 hours), and the anthocyanin content in each sample after irradiation was measured using the analytical method described above. The results are shown in Table 1.

[0034] [Table 1]

[0035] As shown in Table 1, when iron ions were added, regardless of the type of salt, increasing the amount of iron ions reduced the remaining anthocyanin, and actually promoted its degradation. Furthermore, when zinc sulfate was added as zinc ions, there was no change in the remaining anthocyanin. On the other hand, when copper sulfate or copper gluconate was added as copper ions, the remaining anthocyanin increased, and it was clear that the photodegradation of anthocyanins was suppressed. In addition, when other metal ions (manganese ions, aluminum ions, magnesium ions, potassium ions, sodium ions, and tin ions) were used, there was no change in the remaining anthocyanin, similar to zinc ions. In other words, it was clear that the photodegradation-suppressing effect of copper ions was exerted when copper ions were added.

[0036] Example 2: Effect of copper ions on the inhibitory effect of anthocyanin degradation A citrate buffer (pH 3.2, containing 20% ​​ethanol) containing anthocyanins derived from purple carrot pigment was prepared. Copper(II) sulfate pentahydrate was added as copper ions in the amounts shown in Table 2, and the total volume was adjusted to 200 μL to prepare each sample. Subsequently, the samples were irradiated with light (42 kilolux, 25°C, 24 hours), and the anthocyanin content in each sample after irradiation was measured using the analytical method described above. For each sample, the remaining anthocyanin percentage was calculated and compared with the copper-free group (samples 1, 9, 16, 24, 32, 40). Samples with a remaining percentage increase of 5% or more were marked as "Significant effect: ○", samples with an increase of 1% or more were marked as "Effective: △", and samples with no change in the remaining percentage were marked as "No effect: ×". The results are shown in Table 2.

[0037] [Table 2]

[0038] As shown in Table 2, by combining anthocyanins and copper ions, and setting the ratio of copper ion content (B:ppm) to anthocyanin content (A:ppm) to copper ion content (B / A) to 0.000003 or higher, it was found that the retention rate of anthocyanins increased and the photodegradation of anthocyanins was suppressed, regardless of the total anthocyanin and copper ion content.

[0039] Example 3: Effect of pH on the inhibitory effect of copper ions on the degradation of anthocyanins Each sample containing anthocyanins derived from purple carrot pigment was prepared. Specifically, a 10 mM phosphate buffer (containing 20% ​​EtOH) was prepared, and a 10 mM citric acid aqueous solution (containing 20% ​​EtOH) was added to achieve the pH shown in Table 3. Then, anthocyanins and copper(II) sulfate pentahydrate were added in the amounts shown in Table 3, and the total volume was adjusted to 200 μL. Subsequently, each sample was irradiated with light (42 kilolux, 25°C, 24 hours), and the anthocyanin content in each sample after irradiation was measured using the analytical method described above. For each sample, the remaining anthocyanin rate was calculated, and compared to the group without copper, samples with a remaining rate increase of 5% or more were marked as "Significant effect: ○", samples with an increase of 1% or more were marked as "Effective: △", and samples with no change in the remaining rate were marked as "No effect: ×". The results are shown in Table 3.

[0040] [Table 3]

[0041] As shown in Table 3, it was revealed that, regardless of pH level, the inclusion of copper ions increased the retention rate of anthocyanins and suppressed the photodegradation of anthocyanins. [Industrial applicability]

[0042] This invention provides a beverage containing anthocyanins in which the photodegradation of anthocyanins is suppressed. In other words, this invention relates to a novel means for providing a beverage in which anthocyanins are stably retained for a long period of time, and therefore has high industrial applicability.

Claims

1. A beverage containing anthocyanins and copper ions, The beverage wherein the ratio of copper ion content (B: ppm) to anthocyanin content (A: ppm) (B / A) is 0.000003 or more.

2. The beverage according to claim 1, wherein the copper ion content is 0.001 to 1 ppm.

3. The beverage according to claim 1 or 2, wherein the anthocyanin content is 0.25 to 300 ppm.

4. A beverage according to any one of claims 1 to 3, wherein the pH is 6 or less.

5. The beverage according to any one of claims 1 to 4, wherein the copper ions are derived from copper salts or copper yeast.

6. The beverage according to claim 5, wherein the copper salts are copper sulfate or copper gluconate.

7. A beverage according to any one of claims 1 to 6, which is a beverage packaged in a transparent container.

8. A method for producing a beverage containing anthocyanins, The process includes adding anthocyanins and copper ions to the beverage. The method, wherein the ratio (B / A) of the copper ion content (B: ppm) to the anthocyanin content (A: ppm) in the beverage is 0.000003 or more.

9. A method for inhibiting the breakdown of anthocyanins in beverages, The process includes adding anthocyanins and copper ions to the beverage. The method, wherein the ratio (B / A) of the copper ion content (B: ppm) to the anthocyanin content (A: ppm) in the beverage is 0.000003 or more.

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