Fruit juice-containing non-carbonated beverage, method for inhibiting microbial growth thereof, method for manufacturing the same, and microbial growth inhibitor

Abstract

To obtain a sufficient inhibitory effect on microbial growth. [Solution] A non-carbonated fruit juice beverage containing 3.3 ppm or more of iso-alpha acid and with a pH of 4.0 or less.

Description

Technical Field

[0001] The present invention relates to a non-carbonated beverage containing juice, a method for suppressing microbial growth thereof and a manufacturing method, and a microbial growth inhibitor.

Background Art

[0002] In conventional products containing juice, by ensuring that Alicyclobacillus acidoterrestris (AAT) is negative according to the raw material standard of the juice, it is prevented that AAT is mixed into the product. Therefore, juice that has become AAT-positive cannot be used for non-carbonated beverages, and there is a possibility that the production of non-carbonated beverages containing juice will be stagnant until alternative AAT-negative juice can be prepared. In addition, when AAT-positive juice is discarded, it also leads to cost increase and food loss. Patent Document 1 describes an acidic beverage to which acetate is added. It is also described that by adding acetate, a bacteriostatic effect can be obtained against thermophilic acidophilic bacteria without impairing the flavor and appearance of the acidic beverage. Patent Document 2 describes an acidic beverage to which diglycerin myristate is added. It is also described that by adding diglycerin myristate, the growth of thermophilic acidophilic bacteria can be inhibited, good storage stability can be obtained, and effects such as less influence on the color tone, flavor and physical properties of the acidic beverage can be obtained. Furthermore, Patent Document 3 describes an acidic beverage to which a hop extract is added. It is also described that by adding a hop extract to an acidic fruit juice beverage or the like, the growth of thermophilic acidophilic bacteria can be inhibited.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

[0004] However, these prior art techniques have not been able to achieve sufficient inhibition of microbial growth. [Means for solving the problem]

[0005] The inventors have found that a sufficient inhibitory effect on microbial growth can be obtained by using iso-alpha acids. In other words, the present invention is as follows. [1] A non-carbonated fruit juice beverage containing 3.3 ppm or more of iso-alpha acid and with a pH of 4.0 or less. [2] The fruit juice-containing non-carbonated beverage described in [1] above, containing 3.3 ppm to 10 ppm of iso-alpha acid. [3] A method for inhibiting microbial growth in a non-carbonated beverage containing fruit juice with a pH of 4.0 or lower, A method for inhibiting microbial growth, comprising adding iso-alpha acid to a non-carbonated fruit juice beverage so that the iso-alpha acid concentration in the non-carbonated fruit juice beverage is 3.3 ppm or higher. [4] The method for inhibiting microbial growth according to [3] above, wherein the microorganism is a spore-forming bacterium. [5] The method for inhibiting microbial growth according to [3] or [4], wherein the microorganism is a heat-resistant acidophilic bacterium. [6] A method for inhibiting microbial growth according to any one of the above items [3] to [5], wherein the microorganism is of the genus Aricyclobacillus. [7] The method for inhibiting microbial growth according to any one of the above items [3] to [6], wherein the microorganism is Alicyclobacillus acidoterrestris. [8] The method for inhibiting microbial growth according to any one of the above items [3] to [7], wherein the iso-α acid concentration is 3.3 ppm or more and 10 ppm or less. [9] A method for producing a non-carbonated beverage containing fruit juice with a pH of 4.0 or lower, A manufacturing method comprising adding iso-alpha acids to a non-carbonated fruit juice beverage so that the concentration of iso-alpha acids in the non-carbonated fruit juice beverage is 3.3 ppm or higher.

[10] The manufacturing method according to [9], wherein the iso-α acid concentration is 3.3 ppm or more and 10 ppm or less.

[11] A microbial growth inhibitor containing iso-alpha acid. [Effects of the Invention]

[0006] According to the present invention, in non-carbonated beverages containing fruit juice, particularly orange juice beverages, it is possible to suppress the growth of harmful microorganisms without significantly impairing the flavor. [Modes for carrying out the invention]

[0007] This invention relates to a non-carbonated beverage containing fruit juice. In this invention, fruit juice refers to the liquid component obtained by crushing fruit, squeezing or straining the juice, and removing the peel, seeds, etc., as necessary. Fruit juice also includes concentrated liquid components and diluted and reduced versions thereof. Furthermore, fruit juice may be clear juice obtained by clarification methods such as microfiltration, enzymatic treatment, or ultrafiltration, or it may be cloudy juice containing insoluble solids. Examples of fruits include citrus fruits, fruits of the Rosaceae family, grapes, pineapples, guavas, bananas, mangoes, acerola, lychees, papayas, passion fruit, blueberries, kiwifruit, melons, currants, gooseberries and other currant varieties, and fruits of the Ericaceae family such as cranberries. Examples of citrus fruits include oranges, Satsuma mandarins, grapefruits, lemons, limes, yuzu, Iyokan, Natsumikan, Hassaku, Ponkan, Shikuwasa, and Kabosu. Examples of fruits of the Rosaceae family include apricots, strawberries, plums, cherries, Japanese apricots, European pears, Japanese pears, loquats, peaches, apples, prunes, raspberries, and blackberries. In this invention, these fruit juices may be used individually or in combination of two or more types. In the non-carbonated fruit juice beverage of the present invention, the fruit juice content is preferably 20 to 100% by mass, and more preferably 20 to 50% by mass.

[0008] In the present invention, the fruit juice-containing non-carbonated beverage may be a non-alcoholic beverage or an alcoholic beverage. Furthermore, if the non-carbonated beverage in the present invention is an alcoholic beverage, the alcohol content (volume concentration of ethanol) is not particularly limited and is determined as appropriate according to the desired product quality. For example, the alcohol content of the non-carbonated beverage may be adjusted so that the alcohol content is 0.7% by volume or more, or 1% by volume or more, or 2% by volume or more, or 3% by volume or more. Furthermore, if the non-carbonated beverage in the present invention is an alcoholic beverage, the extract content may be 0 to 15 degrees, 1 to 10 degrees, or 3 to 7 degrees. In the present invention, the pH of the fruit juice-containing non-carbonated beverage is preferably 4.0 or lower, and more preferably 3.8 or lower. The lower the pH of the fruit juice-containing non-carbonated beverage, the more effectively the growth of microorganisms can be suppressed.

[0009] The non-carbonated fruit juice beverage of the present invention contains 3.3 ppm or more of iso-alpha acid. By having an iso-alpha acid content of 3.3 ppm or more, a sufficient inhibitory effect on microbial growth can be obtained. The iso-alpha acid content in the non-carbonated fruit juice beverage is preferably 3.3 ppm to 20 ppm, and more preferably 3.3 ppm to 10 ppm. By having an iso-alpha acid content within this range, bitterness can be suppressed. "Iso-alpha acid" is a general term for isohumulone, isoadhumulone, isocohumulone, isoposthumulone, and isoprehumulone. In this invention, iso-alpha acid may be added to adjust the iso-alpha acid content in a non-carbonated fruit juice beverage. Alternatively, iso-alpha acid may be used as a raw material to adjust the iso-alpha acid content in a non-carbonated fruit juice beverage. The iso-alpha acid content in fruit juice-containing non-carbonated beverages can be measured by the high-performance liquid chromatography (HPLC) analysis method described in "7.13 Iso-alpha acids, alpha acids - HPLC method -" of the Revised BCOJ Beer Analysis Method (published by the Japan Brewing Association, edited by the International Technical Committee [Analysis Committee] of the Beer Brewers Association, revised and augmented in 2013).

[0010] In another embodiment, the present invention relates to a method for inhibiting microbial growth in fruit juice-containing non-carbonated beverages. In yet another embodiment, the present invention relates to a microbial growth inhibitor containing iso-α-acids. The present invention provides a method for inhibiting microbial growth in a non-carbonated fruit juice beverage, which includes adding iso-alpha acid to the non-carbonated fruit juice beverage so that the iso-alpha acid concentration in the non-carbonated fruit juice beverage is 3.3 ppm or higher. In this invention, the iso-alpha acid content in the non-carbonated fruit juice beverage may be adjusted by adding iso-alpha acid. Alternatively, the iso-alpha acid content in the non-carbonated fruit juice beverage may be adjusted using raw materials containing iso-alpha acid. Examples of raw materials containing iso-alpha acid include hops, hop pellets, and isopropyl hop extract. As previously mentioned, non-carbonated fruit juice beverages are as described above.

[0011] The microorganism is preferably a spore-forming bacterium. Furthermore, the microorganism is preferably a heat-resistant acidophilic bacterium, and more preferably of the genus Aricyclobacillus.

[0012] In another embodiment, the present invention relates to a method for producing a non-carbonated beverage containing fruit juice. The present invention relates to a method for producing a non-carbonated fruit juice beverage, which involves adding iso-alpha acid to the non-carbonated fruit juice beverage so that the iso-alpha acid concentration in the non-carbonated fruit juice beverage is 3.3 ppm or higher. In this invention, the iso-alpha acid content in the non-carbonated fruit juice beverage may be adjusted by adding iso-alpha acid. Alternatively, the iso-alpha acid content in the non-carbonated fruit juice beverage may be adjusted by using raw materials containing iso-alpha acid. As previously mentioned, non-carbonated fruit juice beverages are as described above. [Examples]

[0013] (Experimental Example) The concentration of iso-α acids required for the growth inhibition of Alicyclobacillus acidoterrestris (AAT) in orange juice was examined by the following method.

[0014] Experimental method Test bacteria: Spores of Alicyclobacillus acidoterrestris Preparation of samples: The concentrated orange juice was diluted with water to adjust the juice concentration to 20% and 50% by mass. Next, sodium hydroxide was added to adjust the pH to 4.0. Further, isomerized hop extract was added to adjust the iso-α acid concentration to 0 - 10 ppm to prepare samples. Inoculation test: The spores of Alicyclobacillus acidoterrestris in glycerol stock (-80°C frozen storage) were thawed, diluted with physiological saline to adjust to 100,000 cells / ml, and subjected to a heat shock at 80°C for 10 minutes to prepare a bacterial solution. 10 ml of each of the prepared samples (orange juice) was added to a 15 ml tube. 100 μl of the prepared bacterial solution was added to the tube containing the sample (the bacterial solution concentration in the sample was 1000 cells / ml). The samples were cultured in an incubator at 45°C for 14 days. Confirmation of growth: Confirmation of viable cell count The samples on the 14th day were smeared on the medium, cultured in an aerobic environment at 45°C, and the number of colonies formed was counted. ※Medium composition (per 1 L) · BACATO Yeast Extract 2.0 g · Soluble Starch 2.0 g · Glucose 1.0 g · Agar 15.0 g

[0015]

Table 1-1

Table 1-2

[0016] In samples with a 20% fruit juice concentration, an iso-α acid concentration of 5 ppm was effective in suppressing growth for two weeks, and in samples with a 50% fruit juice concentration, an iso-α acid concentration of 3.3 ppm was effective in suppressing growth.

Claims

1. A non-carbonated fruit juice beverage containing 3.3 ppm or more of iso-alpha acids and with a pH of 4.0 or less.

2. A non-carbonated fruit juice beverage according to claim 1, containing 3.3 ppm to 10 ppm of iso-alpha acid.

3. A method for inhibiting microbial growth in non-carbonated fruit juice beverages with a pH of 4.0 or lower, A method for inhibiting microbial growth, comprising adding iso-alpha acid to a non-carbonated fruit juice beverage so that the iso-alpha acid concentration in the non-carbonated fruit juice beverage is 3.3 ppm or higher.

4. The method for inhibiting microbial growth according to claim 3, wherein the microorganism is a spore-forming bacterium.

5. The method for inhibiting microbial growth according to claim 3, wherein the microorganism is a heat-resistant acidophilic bacterium.

6. The method for inhibiting microbial growth according to claim 3, wherein the microorganism is of the genus Aricyclobacillus.

7. The method for inhibiting microbial growth according to claim 3, wherein the microorganism is Alicyclobacillus acidoterrestris.

8. The method for inhibiting microbial growth according to any one of claims 3 to 7, wherein the iso-α acid concentration is 3.3 ppm or more and 10 ppm or less.

9. A method for producing a non-carbonated beverage containing fruit juice with a pH of 4.0 or lower, A manufacturing method comprising adding iso-alpha acids to a non-carbonated fruit juice beverage so that the iso-alpha acid concentration in the non-carbonated fruit juice beverage is 3.3 ppm or higher.

10. The manufacturing method according to claim 9, wherein the iso-α acid concentration is 3.3 ppm or more and 10 ppm or less.

11. A microbial growth inhibitor containing iso-alpha acids.

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