Solid yogurt with coenzyme Q10

Abstract

To provide post fermentation type solid yogurt containing coenzyme Q10 that has excellent uniform dispersion stability of coenzyme Q10, excellent transportation resistance, and further a fair texture as goods and preferably nearly the same softness and smooth texture as ordinary yogurt.SOLUTION: Post fermentation type solid yogurt containing coenzyme Q10 contains coenzyme Q10 of 0.02-0.3 wt.% in the whole yogurt and further contains agar. A set of the strength (g wt.% / cm2) of the agar defined below and the content (wt.%) of milk protein is located in a region (A) enclosed by straight lines connecting four points of a point A (60, 5.0), a point B (110, 4.7), a point C (110, 4.1), and a point D (70, 3.4) in this order in Fig.1. The yogurt has a pH of 4.1-4.7 and a median size of yogurt particles of 50-100 μm. The strength of agar: jelly strength of the agar (g / cm2)×addition amount (wt.%) of the agar to the whole yogurt.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to solid yogurt containing coenzyme Q10 and a method for producing the same. [Background technology]

[0002] Coenzyme Q10 is a component of the mitochondrial electron transport chain in human cells, and is involved in the production of ATP by acting as an electron carrier in oxidative phosphorylation reactions. Many research results have been reported showing that it is a substance that shows excellent pharmacological and physiological effects against various diseases. Therefore, various foods containing coenzyme Q10 have been developed.

[0003] On the other hand, because yogurt is a soft food by structure, there are problems such as the contents crumbling during transport by truck or handling, causing the yogurt's surface to lose its smoothness inside the container and causing pieces of the crumbled contents to adhere to the top lid.

[0004] Patent Document 1 describes a method for producing fermented milk, which is characterized in that the dissolved oxygen concentration in the fermented milk raw material mix at the start of fermentation is reduced by replacing it with an inert gas, and describes that this production method produces yogurt with a stable structure that is not broken by impact during transportation. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2005-176603 A Summary of the Invention [Problem to be solved by the invention]

[0006] While we were studying the preparation of yogurt containing coenzyme Q10, we found that when a large amount of coenzyme Q10 is added to yogurt, coenzyme Q10 rises to the surface of the yogurt because it is oil-soluble, and is oxidized and decomposed by oxygen in the upper space of the container, and color unevenness due to coenzyme Q10 occurs. We also found that this problem becomes more pronounced when the yogurt is subjected to vibrations during transportation. Although Patent Document 1 discloses yogurt with a hardness that makes it difficult to break due to impact during transportation, it does not take into consideration home delivery distribution, which requires high transportation resistance because the impact intensity during transportation is large and there are many opportunities for impact, and the transportation resistance is not sufficient.

[0007] In view of the above problems, the object of the present invention is to provide a post-fermented solid yogurt containing coenzyme Q10, which has good uniform dispersion stability of coenzyme Q10, excellent resistance to transportation, and further has a texture that is acceptable for commercial use, preferably having a softness and smooth texture comparable to that of regular yogurt, and a method for producing the same. [Means for solving the problem]

[0008] As a result of extensive research into solving the above problems, the inventors have discovered that in a post-fermented solid yogurt containing coenzyme Q10, by setting the coenzyme Q10 content within a specific range, further blending agar so that the agar strength and milk protein content are each within a specific range, adjusting the pH of the yogurt to a specific range, and further controlling the median diameter of the yogurt particles to a specific size, it is possible to uniformly disperse and stabilize coenzyme Q10 while maintaining an acceptable texture for a product, and also to achieve good transport resistance, thereby completing the present invention.

[0009] That is, the first aspect of the present invention is a yogurt containing 0.02 to 0.3% by weight of coenzyme Q10 in the whole yogurt and further containing agar, the strength of the agar being defined below (g weight% / cm 2), and the milk protein content (wt%) is within area (A) surrounded by the straight lines connecting point A (60, 5.0), point B (110, 4.7), point C (110, 4.1), and point D (70, 3.4) in Figure 1 in that order, and the pH of the yogurt is 4.1 to 4.7, and the median diameter of the yogurt particles is 50 to 100 μm. Agar strength: The jelly strength of the agar (g / cm 2 ) × the amount of the agar added in the entire yogurt (% by weight) Preferably, the agar has a jelly strength of 80 to 300 g / cm 2 The agar is 0.07 to 0.175% by weight in the whole yogurt, and the jelly strength is 500 to 950 g / cm 2 The yogurt contains 0.05 to 0.15% by weight of agar. Preferably, the coenzyme Q10 is ubiquinol. The second aspect of the present invention is a method for preparing a food product which contains 0.02 to 0.3% by weight of coenzyme Q10 in the entire raw material mix, further contains agar, and has a strength of the agar (g·wt% / cm 2 ), and the milk protein content (weight %) is within the region (A) surrounded by the straight lines connecting the four points A (60, 5.0), B (110, 4.7), C (110, 4.1), and D (70, 3.4) in FIG. 1 in that order, homogenizing the raw material mix under a pressure of 10 to 20 MPa, sterilizing the raw material mix at 100 to 120°C for 1 to 60 seconds, adjusting the temperature to 40 to 46°C, adding lactic acid bacteria, filling the raw material mix into containers before the pH drops to 5.7, fermenting the raw material mix at 35 to 45°C until the pH reaches 4.4 to 4.85, and curing the raw material mix at 1 to 10°C for one day or more. Agar strength: The jelly strength of the agar (g / cm 2 ) × the amount of the agar added in the entire yogurt (% by weight) Effect of the Invention

[0010] According to the present invention, it is possible to provide a post-fermented solid yogurt containing Coenzyme Q10, which has good uniform dispersion stability of Coenzyme Q10, excellent resistance to transportation, and furthermore, a texture that is acceptable for commercial use, preferably having a softness and smooth texture comparable to that of regular yogurt, and a method for producing the same. [Brief description of the drawings]

[0011] [Figure 1] 1 is a graph showing preferred ranges of agar strength and milk protein content in a yogurt formulation according to one embodiment of the present invention. [Diagram 2] 1 is a graph showing more preferable ranges of agar strength and milk protein content in the formulation of a yogurt according to one embodiment of the present invention. [Diagram 3] 1 is a graph showing further preferred ranges of agar strength and milk protein content in the formulation of a yogurt according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described in detail. The yogurt according to the present embodiment is a post-fermented yogurt that contains a specific amount of coenzyme Q10 and further contains agar, the strength of the agar and the content of milk protein each falling within a specific range, and the pH of the yogurt and the median diameter of the yogurt particles each falling within a specific range. Here, the post-fermented yogurt refers to a type of yogurt that is produced by adding lactic acid bacteria to a raw material mix that is the raw material of the yogurt, filling it into a container, and then fermenting it (post-fermentation). The yogurt according to the present embodiment is not for drinking, but is provided as a so-called solid yogurt that is to be eaten.

[0013] The coenzyme Q10 is abundant in humans and refers to 2,3-dimethoxy-5-methyl-6-polyprenyl-1,4-benzoquinone with 10 isoprene units in the side chain. In addition, oxidized and reduced forms of the coenzyme Q10 are known, and the oxidized form is named "ubiquinone" and the reduced form is named "ubiquinol". In this embodiment, either ubiquinone or ubiquinol may be used as coenzyme Q10, or both may be used together, but from the viewpoint of oral absorbability and bioavailability, it is preferable to use ubiquinol.

[0014] The content of coenzyme Q10 in the whole yogurt is preferably 0.02 to 0.3% by weight, more preferably 0.03 to 0.3% by weight, even more preferably 0.05 to 0.3% by weight, and particularly preferably 0.1 to 0.3% by weight. If the content of coenzyme Q10 is less than 0.02% by weight, the supply of coenzyme Q10 by eating yogurt may not be efficient. On the other hand, if the content is more than 0.3% by weight, the uniform dispersion stability of coenzyme Q10 in the yogurt may be poor.

[0015] The content of coenzyme Q10 can be measured, for example, as follows. First, mix and stir well so that the yogurt becomes uniform. In the case of yogurt in a cup, it can be easily homogenized by shaking vigorously 200 to 300 times without opening the lid. 4 g of homogenized yogurt is accurately measured into a capped test tube, 10 mL of distilled water and 1 mL of saturated saline are added, and ultrasonic treatment is performed for about 30 seconds to suspend the yogurt well until all lumps disappear. Next, 20 mL of ethanol and 20 mL of n-hexane are added, and the mixture is shaken at 200 rpm for 5 minutes in a shaker. For shaking, it is preferable to use a shaker Model YS-8D manufactured by Yayoi Co., Ltd. and shake in an arc shape. After shaking, centrifuge at 2000 rpm for 2 minutes, put the supernatant into a 100 mL eggplant flask, dry it in an evaporator, and then seal it with nitrogen. When putting it into the eggplant flask, it is important to use a Pasteur pipette to collect as much of the supernatant as possible. In addition, when drying it in an evaporator, care should be taken to prevent foaming and bumping. The test tube is again suspended by ultrasonic treatment for approximately 30 seconds, 20 mL of n-hexane is added, and the mixture is shaken on a shaker at 200 rpm for 5 minutes. Centrifuge at 2000 rpm for 2 minutes, and the supernatant is placed in the 100 mL eggplant flask and dried in an evaporator, then sealed with nitrogen. Dissolve the contents of the eggplant flask in 5 mL of ethanol / n-hexane mixture (4:1) and transfer to a brown volumetric flask. When transferring to the volumetric flask, use a Pasteur pipette to transfer the entire amount.

[0016] The contents of the eggplant flask are dissolved again in 5 mL of ethanol / n-hexane mixture (4:1), transferred to the brown measuring flask, and sonicated. Add ethanol / n-hexane mixture (4:1) to make exactly 20 mL, stir well, and then filter about 1 mL of the mixture through a 0.45 μm filter for HPLC analysis. The HPLC conditions are as follows: column: SYMMETRY C18 (Waters) 250 mm (length) 4.6 mm (inner diameter), mobile phase: C2H5OH:CH3OH = 4:3 (v:v), detection wavelength: 210 nm, flow rate: 1 ml / min, retention time of reduced coenzyme Q10: 9.1 min, retention time of oxidized coenzyme Q10: 13.3 min.

[0017] The yogurt according to the present embodiment contains milk protein. The milk protein means a protein contained in dairy products, and examples thereof include casein protein and whey protein. The milk raw material containing milk protein and serving as a supply source of milk protein is not particularly limited, and examples thereof include buttermilk, cheese, cream cheese, concentrated whey, whey, raw milk, cow's milk, special cow's milk, partially skimmed milk, skim milk, processed milk, milk drink, concentrated milk, skim concentrated milk, unsweetened condensed milk, unsweetened condensed skim milk, sweetened condensed milk, sweetened condensed skim milk, fermented milk or powder thereof, whey protein concentrate (WPC), total milk protein, etc., and at least one selected from these groups may be used. Among them, from the viewpoint of flavor, raw milk, cow's milk, partially skimmed milk, skim milk, and skim milk powder are preferred. In addition, from the viewpoint of health consciousness, skim milk and skim milk powder, which have a low milk fat content, are preferred.

[0018] The yogurt according to this embodiment further contains agar. The agar is a polysaccharide obtained from red algae such as Agar-agar (Grapefruit) and Gracilaria verum, and has a galactose skeleton. Only one type of agar may be used, or multiple types of agar with different jelly strengths may be used in combination.

[0019] In the yogurt according to this embodiment, the strength of the agar (g·wt% / cm 2), and the milk protein content (wt%) is preferably within the region (A) enclosed by the straight lines connecting the four points A (60, 5.0), B (110, 4.7), C (110, 4.1), and D (70, 3.4) in Fig. 1. It is more preferable that the milk protein content (wt%) is within the region (B) enclosed by the straight lines connecting the four points E (67, 4.8), F (102, 4.6), G (102, 4.2), and H (74, 3.7) in Fig. 2. It is even more preferable that the milk protein content (wt%) is within the region (C) enclosed by the straight lines connecting the four points I (76, 4.5), J (91, 4.4), K (91, 4.3), and L (79, 4.0) in Fig. 3.

[0020] On the left side of the line connecting points A and D in Fig. 1, the uniform dispersion stability of coenzyme Q10 and the transport resistance of the yogurt may be poor, and the texture of the yogurt may be deteriorated. On the right side of the line connecting points A and D in Fig. 1, above the line connecting points A and B in Fig. 1, and on the left side of the line connecting points B and C in Fig. 1, i.e., when the strength of the agar is less than 110 g·wt% / cm 2 The texture of yogurt may deteriorate if the agar is in the range below the line connecting points B and C in Figure 1, i.e., if the agar strength is 110 g·wt% / cm 2 The texture of the yogurt may deteriorate in the region beyond the line connecting points A and D in FIG. 1, below the line connecting points C and D in FIG. 1, and to the left of the line connecting points B and C in FIG. 1, i.e., where the strength of the agar is 110 g·wt% / cm 2 Within the range below, the transport resistance of the yogurt may be poor and the texture of the yogurt may be deteriorated.

[0021] Here, the strength of the agar refers to the jelly strength (g / cm) of the agar added to the yogurt. 2 It is expressed as the product of the amount of agar added (wt%) to the entire yogurt. When multiple types of agar with different jelly strengths are used in combination, the strength of each agar is calculated based on the jelly strength and the amount added of each agar, and the total value of the obtained strengths is regarded as the strength of the agar.

[0022] When only one type of agar is used, the jelly strength is 80 to 950 g / cm 2 The yogurt preferably contains 0.07 to 0.8% by weight of agar. The jelly strength is 80 to 950 g / cm 2 The content of agar is more preferably 0.07 to 0.5% by weight, and further preferably 0.1 to 0.3% by weight. When the content of agar is within the above range, the uniform dispersion stability of coenzyme Q10, the texture of the yogurt, and the transport resistance can be improved. The strength of the jelly is 80 to 950 g / cm 2 The agar can be easily selected from agars having an average molecular weight of 60,000 to 500,000.

[0023] When using multiple types of agar with different jelly strengths in combination, it is preferable to use agar with low jelly strength and agar with high jelly strength in combination. Specifically, agar with a jelly strength of 80 to 300 g / cm 2 The agar is 0.07 to 0.175% by weight in the whole yogurt, and the jelly strength is 500 to 950 g / cm 2 The yogurt preferably contains 0.05 to 0.15% by weight of agar. The jelly strength is 80 to 300 g / cm 2 The content of agar is more preferably 0.08 to 0.15% by weight, and further preferably 0.09 to 0.14% by weight. 2 The content of the agar is more preferably 0.06 to 0.14% by weight, and further preferably 0.07 to 0.12% by weight. When the content of each agar is within the above range, the uniform dispersion stability of coenzyme Q10 and the texture and transport resistance of the yogurt can be improved.

[0024] The jelly strength is 80 to 300 g / cm 2 The agar can be easily selected from agars having an average molecular weight of 60,000 to 180,000, and the jelly strength is 500 to 950 g / cm 2 The agar can be easily selected from agars having an average molecular weight of 200,000 to 500,000. Note that agar other than the above two types may be further contained within a range that satisfies the strength of the agar.

[0025] The jelly strength of agar can be measured by the known Nikkansui method. Specifically, a 1.5% solution of agar is prepared, left to solidify at 20°C for 15 hours, and the gel is measured by measuring the surface area of ​​the gel at 1 cm2. 2 The maximum load (g) that the agar can withstand for 20 seconds can be determined. The average molecular weight of agar can be measured by a known method, for example, gel permeation chromatography.

[0026] The coenzyme Q10-containing post-fermented solid yogurt according to this embodiment has a pH of preferably 4.1 to 4.7, more preferably 4.2 to 4.6, and even more preferably 4.3 to 4.6. If the pH is less than 4.1, the texture and flavor of the yogurt may be poor. If the pH is more than 4.7, the transport resistance of the yogurt may be poor.

[0027] In the post-fermented solid yogurt containing coenzyme Q10 according to the present embodiment, the median diameter of the yogurt particles contained therein is preferably 50 to 100 μm, more preferably 54 to 90 μm, and even more preferably 54 to 85 μm. If the median diameter of the yogurt particles is smaller than 50 μm, the uniform dispersion stability of coenzyme Q10 may be poor. On the other hand, if it exceeds 100 μm, the texture of the yogurt may be deteriorated. The median diameter of the yogurt particles can be measured by a known method, and examples of the measurement method include a method of measuring using a laser diffraction / scattering type particle size distribution measurement device. In this case, water is used as a dispersion medium. Examples of the laser diffraction / scattering type particle size distribution measurement device include LA-960V2 (manufactured by Horiba, Ltd.). In addition, when measuring, the yogurt curd is collected without being broken and set in the measurement device as it is.

[0028] The yogurt according to this embodiment may contain other ingredients in addition to the coenzyme Q10, the agar, and the dairy ingredients containing the milk protein, as long as the effects of the invention are not impaired. Examples of the other ingredients include carbohydrates, stabilizers, oils and fats, emulsifiers, flavorings, colorants, flavoring materials, antioxidants, etc.

[0029] The carbohydrate is not particularly limited, but examples thereof include sugar, fructose, glucose, starch syrup, reduced starch syrup, honey, isomerized sugar, invert sugar, oligosaccharides (isomaltooligosaccharides, reduced xylooligosaccharides, reduced gentiooligosaccharides, xylooligosaccharides, gentiooligosaccharides, nigerooligosaccharides, theanderoligosaccharides, soybean oligosaccharides, etc.), trehalose, sugar alcohols (maltitol, erythritol, sorbitol, reduced palatinose, xylitol, lactitol, etc.), and sugar-bound starch syrup (coupling sugar). At least one selected from these groups can be used.

[0030] Among these carbohydrates, sugar, fructose, glucose, starch syrup, reduced starch syrup, honey, isomerized sugar, invert sugar, sugar alcohols (maltitol, erythritol, sorbitol, reduced palatinose, xylitol, lactitol, etc.) are preferred from the viewpoint of having a good sweetness.

[0031] In addition, from the viewpoint of low sugar content for health consciousness, the sugar can be replaced with a high-intensity sweetener.The high-intensity sweetener is not particularly limited, but can be, for example, aspartame, alitame, monatin, licorice extract, sweet tea extract, Momordica flower extract, saccharin, saccharin sodium, acesulfame potassium, sucralose, neotame, thaumatin, Momordica flower extract, etc., and at least one selected from these groups can be used.From the viewpoint of both good sweetness and low sugar content, it is preferable to use reduced palatinose and sucralose in combination.

[0032] The stabilizer is not particularly limited, but examples thereof include gum arabic, carrageenan, alginic acids (alginic acid, alginate), low methoxyl pectin (LM pectin), high methoxyl pectin (HM pectin), guar gum, tara gum, locust bean gum, tamarind seed gum, psyllium seed gum, water-soluble soybean polysaccharides, glucomannan, starch, modified starch, processed starch, dextrin, gellan gum, xanthan gum, pullulan, curdlan, cellulose, carboxymethylcellulose salt, methylcellulose, chitin, chitosan, gelatin, and the like. At least one selected from this group can be used.

[0033] The oils and fats are not particularly limited as long as they are edible, and examples thereof include various animal and vegetable oils and fats such as soybean oil, cottonseed oil, corn oil, safflower oil, olive oil, palm oil, rapeseed oil, rice bran oil, coconut oil, palm kernel oil, milk fat, lard, and fish oil, as well as processed oils and fats such as hardened oils, fractionated oils, and interesterified oils thereof. At least one selected from this group can be used.

[0034] The emulsifier is not particularly limited as long as it is edible, and examples thereof include monoglycerides, monoglyceride derivatives having an organic acid bonded thereto, sucrose fatty acid esters, polyglycerol fatty acid esters, propylene glycol fatty acid esters, polyglycerol condensed ricinoleic acid esters, calcium stearoyl lactylate, and sodium stearoyl lactylate, and at least one selected from this group can be used.

[0035] The flavoring agent is not particularly limited, and may be a natural flavor or a synthetic flavor, such as a yogurt flavor, a fruit flavor, a vegetable flavor, or a mixture thereof. Examples of the fruit flavor include citrus fruits such as lemon, orange, mandarin orange, grapefruit, shikuwasa, yuzu, and lime, strawberry, peach, grape, apple, pineapple, mango, melon, and banana, and at least one selected from these groups may be used.

[0036] The coloring agent is not particularly limited as long as it is edible, and examples thereof include Monascus colorant, gardenia, lac, cochineal, carotene, etc., and at least one selected from this group can be used.

[0037] The flavoring material is not particularly limited as long as it is edible, and examples thereof include strawberries, peaches, mangoes, papayas, watermelons, melons, apples, persimmons, pears (including European pears), bananas, loquats, pomegranates, lychees, plums, apricots, pineapples, grapes, kiwis, plums, Japanese apricots, cherries, passion fruit, blackcurrants, red currants; berries such as cranberries, blackberries, blueberries, and raspberries; citrus fruits such as oranges and grapefruits, aloe vera, and the like, which are cut, pureed, or grated, from the pulp, leaf pulp, seeds, or peel, as well as cut products such as jellies, agar gels, nata de coco, and almond tofu that imitate these fruits, and at least one type selected from this group can be used.

[0038] The antioxidant is not particularly limited as long as it is edible, and examples thereof include vitamin A, carotenoids, vitamin C, vitamin E, selenium, flavonoids, polyphenols, lycopene, lutein, lignans, etc., and at least one selected from this group can be used.

[0039] The post-fermented solid yogurt containing coenzyme Q10 according to this embodiment can be produced through a process of mixing and dissolving the raw materials, a homogenization process, a sterilization process, a process of adding lactic acid bacteria, a process of filling into containers, a fermentation process, and a curing process. Each process is described in detail below, but the method for producing the yogurt according to this embodiment is not limited to the following description.

[0040] (Mixing and dissolving process) The above-mentioned raw materials for yogurt (i.e., coenzyme Q10, agar, milk raw materials containing milk protein, and other optional ingredients) are all mixed and dissolved to obtain a raw material mix. At this time, the coenzyme Q10 may be mixed simultaneously with the other raw materials, but from the viewpoint of enhancing the uniform dispersion stability of coenzyme Q10, it is preferable to first prepare a mixed liquid by mixing and dissolving the raw materials other than coenzyme Q10, extract a part of the mixed liquid, add coenzyme Q10 to the extracted mixed liquid, mix and stir with a homomixer, and then mix and stir with the remaining mixed liquid. Since the melting point of coenzyme Q10 is about 50°C, it is preferable to adjust the temperature of the mixed liquid by mixing and dissolving the raw materials other than coenzyme Q10 to 50-70°C and add coenzyme Q10 thereto. The mixing and stirring conditions with the homomixer are 80-250S. -1 Preferably, the time is 1 to 10 minutes, and 100 to 200 seconds. -1 It is more preferable to mix at a stirring speed of 80 S for 3 to 7 minutes. -1 In the above, if the stirring time is longer than 1 minute, the uniform dispersion stability of coenzyme Q10 can be improved. However, if the stirring speed is 200 s -1 If mixed more quickly or for longer than 10 minutes, the effect may plateau.

[0041] (homogenization process) The raw material mix obtained in the mixing and dissolving step is adjusted to a temperature of 50 to 70°C, and then homogenized to obtain a raw material mix after homogenization. The homogenization can be performed using a known homogenization device, and examples of such devices include, but are not limited to, a homogenizer, a microfluidizer, a colloid mill, and the like. The pressure during the homogenization is preferably 10 to 20 MPa, more preferably 12 to 20 MPa, and even more preferably 12 to 18 MPa. If the pressure during the homogenization is less than 10 MPa, the texture of the yogurt may feel rough, or the fineness of the oil-soluble coenzyme Q10 may be insufficient, resulting in poor uniform dispersion stability of the coenzyme Q10. On the other hand, if the pressure exceeds 20 MPa, the oil droplets of the once finely-divided coenzyme Q10 may break and coalesce with each other, resulting in poor uniform dispersion stability of the coenzyme Q10.

[0042] (sterilization process) The homogenized raw mix obtained in the homogenization step is sterilized at 100 to 120°C for 1 to 60 seconds to obtain a sterilized raw mix. The sterilization temperature is more preferably 105 to 120°C, and even more preferably 105 to 115°C. If the sterilization temperature is lower than 100°C, it may be difficult to obtain the effect of the sterilization treatment or the agar may not be sufficiently dissolved. On the other hand, if it exceeds 120°C, the protein may be thermally denatured and the smoothness of the yogurt may decrease. The sterilization time is more preferably 1 to 30 seconds, and even more preferably 1 to 15 seconds. If the sterilization time is shorter than 1 second, it may be difficult to obtain the effect of the sterilization treatment or the agar may not be sufficiently dissolved. On the other hand, if it is longer than 60 seconds, the protein may be thermally denatured and the smoothness of the yogurt may decrease.

[0043] (Lactic acid bacteria addition process) The raw material mix after sterilization obtained in the sterilization step is adjusted to a temperature of 40 to 46° C., the lactic acid bacteria are added, and the mixture is stirred to obtain a raw material mix after addition of lactic acid bacteria. The adjusted temperature is more preferably 40 to 44° C., and even more preferably 40 to 42° C. If the adjusted temperature is outside the range of 40 to 46° C., the activity of the lactic acid bacteria may decrease, which may result in a longer fermentation time or a worse flavor of the yogurt.

[0044] As the lactic acid bacteria, a lactic acid bacteria starter may be used. The lactic acid bacteria starter is not particularly limited, and can be one that is usually used in yogurt. For example, lactococci belonging to Lactococcus, Streptococcus, Pediococcus, and Leuconostoc, lactobacilli belonging to Lactobacillus, and Bifidobacterium can be mentioned. Specific examples include Streptococcus thermophilus, Lactobacillus delbrueckii subsp. Bulgaricus, Lactobacillus acidophilus, and Bifidobacterium lactis.

[0045] The amount of the lactic acid bacteria to be added is not particularly limited, and may be an amount normally used in making yogurt. For example, 0.00001 to 5 parts by weight may be added per 100 parts by weight of the total raw material mix, with 0.00001 to 0.05 parts by weight being the standard for the freeze-dried type and 0.01 to 5 parts by weight being the standard for the fermented liquid type.

[0046] (Container filling process) The raw material mix after the addition of the lactic acid bacteria obtained in the lactic acid bacteria addition step is filled into a container before the pH of the raw material mix drops to 5.7 after the addition of the lactic acid bacteria, to obtain the raw material mix after filling into the container. The pH at the time of filling is more preferably 6.1 or more, and even more preferably 6.3 or more. If the pH at the time of filling is less than 5.7, the formation of fermented curd may proceed before filling and may be destroyed during filling, resulting in whey separation. The upper limit of the pH at the time of filling is not particularly limited, but may be, for example, 6.7 or less. To adjust the pH at the time of filling, the container may be filled within 2.5 hours after the addition of the lactic acid bacteria. The pH may be measured according to a conventional method, for example, using a pH meter ("F-52" manufactured by Horiba, Ltd.).

[0047] (Fermentation process) The raw material mix filled in the container obtained in the filling step is fermented at 35 to 45°C until the pH reaches 4.4 to 4.85 to obtain a raw material mix after fermentation treatment. The fermentation temperature is more preferably 37 to 43°C, and even more preferably 38 to 42°C. If the fermentation temperature is outside the range of 35 to 45°C, the activity of the lactic acid bacteria decreases, which may result in a long fermentation time or a deterioration in the flavor of the yogurt obtained after the cooling step described below. The pH at the end of the fermentation is more preferably 4.5 to 4.8. If the pH at the end of the fermentation is less than 4.4, the flavor and texture of the yogurt obtained after the cooling step may be deteriorated. On the other hand, if the pH is higher than 4.85, the flavor of the yogurt obtained after the cooling step may be insufficient. To adjust the pH at the end of the fermentation to within the above range, the retention time at the fermentation temperature may be, for example, about 5 to 10 hours.

[0048] (Curing process) The yogurt according to the present embodiment can be obtained by curing the raw material mix after the fermentation treatment obtained in the fermentation step at 1 to 10°C for one day or more. The temperature during the curing is more preferably 1 to 8°C, and even more preferably 1 to 6°C. If the temperature during the curing is lower than 1°C, the yogurt may freeze, which may deteriorate the uniform dispersion stability of coenzyme Q10. On the other hand, if the temperature is higher than 10°C, the hygienic shelf life may decrease. From a hygienic standpoint, the number of days for curing is preferably 21 days or less.

[0049] According to the yogurt production method described above, it is possible to produce post-fermented solid yogurt that has good uniform dispersion stability of coenzyme Q10, has excellent resistance to transportation, and has a texture that is acceptable for commercial use, preferably having a soft and smooth texture comparable to that of regular yogurt. EXAMPLES

[0050] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the examples, "parts" and "%" are by weight.

[0051] The raw materials used in the examples and comparative examples are as follows. 1) Kaneka skim milk powder (milk protein content: 34.0%) 2) Ina Agar Co., Ltd. "Ina Agar SY-6" (jelly strength: 630 g / cm 2 , average molecular weight: 270,000) 3) San-Ei Gen F.F.I. Co., Ltd. "Sunsweet SU-100" (15% sucralose, 85% reduced palatinose) 4) Kaneka Corporation "Kaneka QH" (reduced coenzyme Q10) 5) “MPC80 SOLMIKO” manufactured by Glanbia Nutritionals (Milk protein content: 80.5%) 6) Ina Kanten Co., Ltd. "Ultra Agar AX-200" (jelly strength: 200g / cm 2 , average molecular weight: 110,000) 7) Kaneka Corporation's "Kaneka Q10" (oxidized coenzyme Q10) 8) "AP-50F" manufactured by Nippi Corporation 9) "Smart Taste" by San-Ei Gen F.F.I. Co., Ltd. 10) "UNIPECTINE LMSN325 CITRUS" manufactured by Unitech Foods Co., Ltd.

[0052] <Measurement of the median diameter of yogurt particles> The median diameter of yogurt particles was measured by taking a sample from the yogurt curd without breaking it down, and using a laser diffraction / scattering type particle size distribution analyzer LA-960V2 (manufactured by Horiba, Ltd.) with water as the dispersion medium.

[0053] <Measurement of pH of yogurt> The pH of the yogurt was measured using a pH meter ("F-52" manufactured by Horiba, Ltd.).

[0054] <Method for measuring Coenzyme Q10 content> 4 g of yogurt was accurately weighed into a capped test tube, 10 mL of distilled water and 1 mL of saturated saline were added, and the mixture was sonicated for about 30 seconds to suspend the mixture. 20 mL of ethanol and 20 mL of n-hexane were added, and the mixture was shaken for 5 minutes at 200 rpm in a shaker. Centrifugation was performed for 2 minutes at 2000 rpm, and the supernatant was placed in a 100 mL eggplant flask, dried in an evaporator, and then sealed with nitrogen. The test tube was again sonicated for about 30 seconds to suspend the mixture, and 20 mL of n-hexane was added, and the mixture was shaken for 5 minutes at 200 rpm in a shaker. Centrifugation was performed for 2 minutes at 2000 rpm, and the supernatant was placed in the 100 mL eggplant flask, dried in an evaporator, and then sealed with nitrogen. The contents of the eggplant flask were dissolved in 5 mL of ethanol / n-hexane mixture (4:1) and transferred to a brown measuring flask. The contents of the eggplant flask were again dissolved in 5 mL of ethanol / n-hexane mixture (4:1), transferred to the brown measuring flask, and sonicated. A mixture of ethanol / n-hexane (4:1) was added to make exactly 20 mL, and about 1 mL of the solution was filtered through a 0.45 μm filter and subjected to HPLC analysis.

[0055] (HPLC conditions) Analytical column: SYMMETRY C18 (Waters) 250 mm (length) 4.6 mm (inner diameter) Mobile phase: C2H5OH:CH3OH=4:3(v:v) Detection wavelength: 210nm Flow rate: 1ml / min Reduced coenzyme Q10 retention time: 9.1 min Oxidized coenzyme Q10 retention time: 13.3 min

[0056] <Yogurt evaluation> (Uniform dispersion stability of coenzyme Q10) The top lids of the yogurt cups obtained in the Examples and Comparative Examples were removed, and the coenzyme Q10 content (X) in the yogurt within approximately 10 mm from the surface and the coenzyme Q10 content (Y) in the yogurt within approximately 10 mm from the bottom of the container (approximately 27 to 37 mm from the surface of the yogurt) were measured, and the uniform dispersion stability was calculated using the following formula. Homodispersion stability (%)=[{(X)-(Y)} / {(X)+(Y)} / 2]×100

[0057] Measurements were carried out on five pieces for each Example or Comparative Example, and evaluation was carried out based on the average value. The evaluation criteria at that time were as follows: 5 points: Uniform dispersion stability is less than 5% 4 points: Uniform dispersion stability is 5% or more and less than 10% 3 points: Uniform dispersion stability is 10% or more and less than 15% 2 points: Uniform dispersion stability is 15% or more and less than 25% 1 point: Uniform dispersion stability of 25% or more

[0058] (Transportation durability of yogurt) Ten yogurts of each type obtained in the Examples and Comparative Examples, which were 6 days after production, were packed in a cardboard box with 2 pieces vertically and 5 pieces horizontally so that there were no gaps, and then transported by refrigerated home delivery from Kaneka Takasago Industrial Works (Takasago City, Hyogo Prefecture) to Kaneka Tokyo Headquarters (Akasaka, Minato Ward, Tokyo). Immediately after arrival, the cup was tilted at a 45 degree angle, and the degree of crumbling was evaluated by an experienced panelist according to the following criteria. The transportation test was carried out five times on different days, and the average score was used as the evaluation score. 5 points: Much better than the yogurt of Example 2, no loss of shape or water separation at all, and extremely good transport resistance 4 points: Better than the yogurt of Example 2, no loss of shape or water separation, and good transport resistance 3 points: Equivalent to the yogurt of Example 2, with almost no loss of shape or water separation, and good transport resistance 2 points: Worse than the yogurt of Example 2, with some deformation and water separation, and poor transport resistance 1 point: Much worse than the yogurt of Example 2, with severe deformation and water separation, and no resistance to transportation at all

[0059] (Yogurt texture) A sensory evaluation was carried out by having 10 experienced panelists taste the yogurts obtained in the Examples and Comparative Examples, which had been adjusted to 10°C, and the average of the scores was regarded as the sensory evaluation. The evaluation criteria were as follows: 5 points: Better than the yogurt of Example 13, extremely good in softness and smoothness, and comparable to general yogurt ("Megumi Gasseri SP Strain Yogurt" manufactured by Megmilk Snow Brand Co., Ltd., the same below). 4 points: Equivalent to the yogurt of Example 13, with good softness and smoothness, but slightly inferior to general yogurt 3 points: Slightly worse than the yogurt of Example 13, slightly worse in softness and smoothness, and inferior to general yogurt, but at a level that is acceptable as a product. 2 points: Worse than the yogurt of Example 13, not very soft or smooth, and worse than general yogurt 1 point: Much worse than the yogurt of Example 13, no softness or smoothness at all, and clearly worse than general yogurt

[0060] (comprehensive evaluation) A comprehensive evaluation was conducted based on the results of the evaluation of the uniform dispersion stability of coenzyme Q10, transport resistance, and the texture of the yogurt. The evaluation criteria were as follows: A: Coenzyme Q10 uniform dispersion stability, transport resistance, and texture all satisfy the criteria of 4.0 to 5.0. B: Coenzyme Q10 uniform dispersion stability, transport resistance, and texture are all 3.5 to 5.0 points, with at least one being 3.5 to less than 4.0 C: Coenzyme Q10 uniform dispersion stability, transport resistance, and texture are all 3.0 to 5.0 points, with at least one being 3.0 to less than 3.5. D: Coenzyme Q10 uniform dispersion stability, transport resistance, and texture are all 2.0 to 5.0 points, with at least one being 2.0 to less than 3.0 E: At least one of the evaluations of uniform dispersion stability, transport resistance, and texture of coenzyme Q10 is less than 2.0 points.

[0061] Example 1: Preparation of yogurt A raw material mix was prepared by adding and dissolving 14.5 parts by weight of skim milk powder, 0.10 parts by weight of agar A, 0.05 parts by weight of sweetener, and 85.21 parts by weight of water. 3 parts by weight of the raw material mix was removed, and 0.14 parts by weight of reduced coenzyme Q10 was added, and the mixture was mixed in a homogenizer at 160°C for 1 hour. -1 The mixture was stirred for 5 minutes at 40°C, and the dissolved and dispersed solution was added to the remaining raw mix. The obtained raw mix was preheated to 60°C, homogenized at a pressure of 14 MPa using a high-pressure homogenizer, heated to 110°C using a plate-type heat exchanger, and held for 2 seconds for sterilization. It was then cooled to 40°C, and 0.0176 parts by weight of lactic acid bacteria starter (Streptococcus thermophilus, Lactobacillus delbrueckii subsp. Bulgaricus, Lactobacillus acidophilus, Bifidobacterium lactis) was added, stirred for 10 minutes, and 90 g was filled into a container (cylindrical shape with upper diameter: 64.4 mm, bottom diameter: 50.6 mm, height: 54.4 mm). The pH of the raw mix when filled into the container was 6.5. Fermentation was performed at 40°C until the pH became 4.7, and then moved to a refrigerator at 4°C to cool, and then cured at that temperature for 7 days to produce yogurt. The results of the pH of the obtained yogurt, the median diameter of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the resistance to transportation, and the texture are shown in Table 1.

[0062] [Table 1]

[0063] (Examples 2 to 8) Preparation of yogurt According to the formulation of Table 1, in Example 1, 14.5 parts by weight of skim milk powder and 0.10 parts by weight of agar A were changed to 10.4 parts by weight and 0.11 parts by weight (Example 2), 12.0 parts by weight and 0.12 parts by weight (Example 3), 13.2 parts by weight and 0.12 parts by weight (Example 4), 12.7 parts by weight and 0.13 parts by weight (Example 5), 14.0 parts by weight and 0.15 parts by weight (Example 6), 12.0 parts by weight and 0.17 parts by weight (Example 7), or 13.7 parts by weight and 0.17 parts by weight (Example 8), respectively, and yogurt was prepared in the same manner as in Example 1, except that the total amount was adjusted with water. The results of the pH of the obtained yogurt, the median diameter of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the transport resistance, and the texture are shown in Table 1.

[0064] As is clear from Table 1, the yogurts of Examples 1 to 8, which had agar strength and milk protein content falling within the range of region (A) in Figure 1, were evaluated as having good uniform dispersion stability of coenzyme Q10, resistance to transportation, and texture. In particular, the yogurts of Examples 3 to 5, which fell within the range of region (B) in Figure 2, were evaluated as having better uniform dispersion stability, resistance to transportation, and texture, and the yogurt of Example 5, which fell within the range of region (C) in Figure 3, was evaluated as having even better uniform dispersion stability, and the yogurt of Example 5, which fell within the range of region (C) in Figure 3, was evaluated as having even better texture.

[0065] (Comparative Examples 1 to 6) Preparation of Yogurt According to the formulation of Table 2, in Example 1, 14.5 parts by weight of skim milk powder and 0.10 parts by weight of agar A were changed to 11.0 parts by weight and 0.08 parts by weight (Comparative Example 1), 9.0 parts by weight and 0.10 parts by weight (Comparative Example 2), 15.3 parts by weight and 0.10 parts by weight (Comparative Example 3), 9.5 parts by weight and 0.15 parts by weight (Comparative Example 4), 11.7 parts by weight and 0.18 parts by weight (Comparative Example 5), or 14.4 parts by weight and 0.18 parts by weight (Comparative Example 6), respectively, and yogurt was prepared in the same manner as in Example 1, except that the total amount was adjusted with water. The results of the pH of the obtained yogurt, the median diameter of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the transport resistance, and the texture are shown in Table 2.

[0066] [Table 2]

[0067] As is clear from Table 2, the yogurts of Comparative Examples 1 to 6, in which the agar strength and milk protein content were not within the range of region (A) in Figure 1, were inferior in at least one of the evaluations of transport resistance and texture.

[0068] Example 9: Preparation of yogurt Yogurt was prepared in the same manner as in Example 5, except that the amount of skim milk powder in Example 5 was changed from 12.7 parts by weight to 9.5 parts by weight, 1.5 parts by weight of milk protein was added, and the total amount was adjusted with water according to the formulation in Table 3. The results of the pH of the obtained yogurt, the median size of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the resistance to transportation, and the texture are shown in Table 3.

[0069] [Table 3]

[0070] As is clear from Table 3, the yogurt of Example 9, in which the type of milk protein was changed, was evaluated as being favorable in terms of uniform dispersion stability of coenzyme Q10, resistance to transportation, and texture, similar to the yogurt of Example 5.

[0071] (Example 10) Preparation of yogurt Yogurt was prepared in the same manner as in Example 5, except that the amount of agar A in Example 5 was changed from 0.13 parts by weight to 0.10 parts by weight in accordance with the formulation in Table 3, 0.10 parts by weight of agar B was further added, and the total amount was adjusted with water. The results of the pH of the obtained yogurt, the median diameter of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the transport resistance, and the texture are shown in Table 3.

[0072] As is clear from Table 3, the strength of the agar was changed to produce a jelly with a strength of 80 to 300 g / cm 2 Agar B has a jelly strength of 500 to 950 g / cm 2The yogurt of Example 10, which used two types of agar A falling within the above range, was evaluated as having good uniform dispersion stability of coenzyme Q10, resistance to transportation, and texture, and was superior to the yogurt of Example 5 in terms of resistance to transportation and texture.

[0073] (Example 11) Preparation of yogurt Yogurt was prepared in the same manner as in Example 5, except that the reduced coenzyme Q10 in Example 5 was changed from 0.14 parts by weight to 0.30 parts by weight in accordance with the formulation in Table 3, and the total amount was adjusted with water. The results of the pH of the obtained yogurt, the median size of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the resistance to transportation, and the texture are shown in Table 3.

[0074] As is clear from Table 3, the yogurt of Example 11, which had a high reduced coenzyme Q10 content of 0.30% by weight, was evaluated as being good in terms of uniform dispersion stability of coenzyme Q10, resistance to transportation, and texture, similar to that of Example 5.

[0075] (Example 12) Preparation of yogurt Yogurt was prepared in the same manner as in Example 5, except that reduced coenzyme Q10 was replaced with oxidized coenzyme Q10 according to the formulation in Table 3. The results of the pH of the obtained yogurt, the median diameter of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the transport resistance, and the texture are shown in Table 3.

[0076] As is clear from Table 3, the yogurt of Example 12, to which oxidized coenzyme Q10 was added, was evaluated as being favorable in terms of uniform dispersion stability of coenzyme Q10, resistance to transportation, and texture, similar to that of Example 5.

[0077] (Comparative Examples 7 to 9) Preparation of Yogurt Yogurt was prepared in the same manner as in Example 10, except that 0.1 part by weight of agar A and 0.1 part by weight of agar B in Example 10 were changed to 0.2 part by weight of gelatin (Comparative Example 7), 0.3 part by weight of dextrin (Comparative Example 8), or 0.13 part by weight of pectin (Comparative Example 9) in accordance with the formulation in Table 4, and the total amount was adjusted with water. The results of the pH of the obtained yogurt, the median diameter of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the transport resistance, and the texture are shown in Table 4.

[0078] [Table 4]

[0079] As is clear from Table 4, the yogurt with added gelatin (Comparative Example 7), the yogurt with added dextrin (Comparative Example 8), and the yogurt using pectin (Comparative Example 9) all had poor evaluations of the uniform dispersion stability and transport resistance of coenzyme Q10.

[0080] (Examples 13 to 14 and Comparative Example 10) Preparation of yogurt Yogurt was prepared in the same manner as in Example 10, except that the pH at the end of fermentation in Example 10 was changed from 4.7 to pH 4.4 (Example 13), pH 4.85 (Example 14), or pH 5.0 (Comparative Example 10) according to the formulation in Table 5. The results of the pH of the obtained yogurt, the median size of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the resistance to transportation, and the texture are shown in Table 5.

[0081] [Table 5]

[0082] As is clear from Table 5, the yogurt of Example 13 (pH 4.1) and the yogurt of Example 14 (pH 4.7), both of which had a pH in the range of 4.1 to 4.7, were evaluated as being good in terms of uniform dispersion stability of coenzyme Q10, resistance to transportation, and texture. On the other hand, the yogurt of Comparative Example 10, which had a high pH of 4.8, was evaluated as being poor in terms of resistance to transportation.

[0083] (Example 15) Preparation of yogurt Yogurt was prepared in the same manner as in Example 10, except that the pH at the time of filling the container was changed from 6.5 to 5.7, according to the formulation in Table 5. The results of the pH of the obtained yogurt, the median diameter of the yogurt particles, the uniform dispersion stability of coenzyme Q10, the resistance to transportation, and the texture are shown in Table 5.

[0084] As is clear from Table 5, the yogurt (Example 15) obtained by changing the pH when filled into the container was evaluated as having good uniform dispersion stability of coenzyme Q10, resistance to transportation, and texture.

Claims

1. The yogurt contains 0.02 to 0.3% by weight of coenzyme Q10. Further containing agar, The strength of the agar (g / wt% / cm ２ ), and the milk protein content (wt%) is within an area (A) surrounded by straight lines sequentially connecting four points, namely, point A (60, 5.0), point B (110, 4.7), point C (110, 4.1), and point D (70, 3.4) in FIG. 1 ; The pH of the yogurt is 4.1 to 4.7, A post-fermented solid yogurt containing coenzyme Q10, the median diameter of the yogurt particles being 50 to 100 μm. Agar strength: the jelly strength of the agar (g / cm ２ ) × the amount of the agar added in the entire yogurt (% by weight)

2. The agar has a jelly strength of 80 to 300 g / cm ２ The agar is 0.07 to 0.175% by weight in the whole yogurt, and the jelly strength is 500 to 950 g / cm ２ 2. The post-fermented solid yogurt containing coenzyme Q10 according to claim 1, wherein the agar is contained in an amount of 0.05 to 0.15% by weight based on the total weight of the yogurt.

3. 3. The post-fermented solid yogurt containing coenzyme Q10 according to claim 1 or 2, wherein the coenzyme Q10 is ubiquinol.

4. The raw material mix contains 0.02 to 0.3% by weight of coenzyme Q10 and further contains agar, and the strength of the agar (g weight% / cm ２ 1 ), and the milk protein content (wt%) is within the region (A) surrounded by the straight lines connecting the four points A (60, 5.0), B (110, 4.7), C (110, 4.1), and D (70, 3.4) in FIG. 1 in that order, homogenizing the raw material mix at a pressure of 10 to 20 MPa, sterilizing the raw material mix at 100 to 120°C for 1 to 60 seconds, adjusting the temperature to 40 to 46°C, adding lactic acid bacteria, filling the raw material mix into a container before the pH drops to 5.7, fermenting the raw material mix at 35 to 45°C until the pH reaches 4.4 to 4.85, and curing the raw material mix at 1 to 10°C for one day or more. Agar strength: the jelly strength of the agar (g / cm ２ ) × the amount of the agar added in the entire yogurt (% by weight)

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