JP2002017254A - Light fast fermented milk, light fast fermented milk product and method for producing the same - Google Patents

Abstract

(57) [Summary] [Problem] Even when filled in a light-transmitting synthetic resin container and stored under severe light irradiation conditions, survival of lactic acid bacteria is maintained, and flavor and physical properties are not deteriorated. Providing fermented milk and fermented milk products. SOLUTION: Fermented milk obtained by fermenting lactic acid bacteria and containing one or more compounds selected from cysteine, vitamin C, bayberry extract, rutin and fruit juice, and fermented milk thereof , In a light-permeable container.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a light-resistant fermented milk and a light-resistant fermented dairy product, and more particularly to a light-transmitting container filled with a light-transmissive container, which survives even when stored under severe light irradiation. The present invention relates to a light-resistant fermented milk in which the number of lactic acid bacteria can be guaranteed, and in which discoloration is suppressed, a light-resistant fermented milk product filled with the light-resistant fermented milk, and a method for producing the same.

[0002]

2. Description of the Related Art Fermented milk containing lactic acid bacteria and Bifidobacterium bacteria has been widely eaten and consumed as health foods having physiological activities such as intestinal regulation and immunostimulatory effects.
Since the physiological action of fermented milk often depends on the number of lactic acid bacteria and Bifidobacterium bacteria in the product, many attempts have been made to improve the growth during bacterial culture and the survival of the product during storage. . For example, tea extracts and chlorella are said to have the effect of promoting the growth of lactic acid bacteria, and as a survival improver for Bifidobacterium bacteria, sugar alcohols such as erythritol and lactitol, calcium gluconate, and lactulose. Etc. have been proposed.

On the other hand, glass bottles have been used for a long time as a material of containers for filling and packaging fermented milk to produce fermented milk products. There is also a problem. For this reason, in recent years, synthetic resins such as polystyrene and polyethylene and paper have been used as container materials. Above all, synthetic resins are useful as materials that are easy to use in terms of good moldability and cost.

[0004] By the way, even if the survival improver described above is used, if the storage condition of the product is poor for the growth of the bacterium, the killing of the bacterium may not be completely suppressed. The present inventor's research has revealed that the fermented milk product filled and packaged in a light-transmissive container, when continuously exposed to strong light such as sunlight, reduces the number of bacteria in the product. It has become. At the product distribution stage or the like, sunlight may directly hit the product, so maintaining the bacterial count in such a case is also important in order to supply a homogeneous product to consumers.

[0005] However, at present, no measures have been taken to reduce the number of bacteria due to such severe light irradiation.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention is intended to maintain the survival of lactic acid bacteria even when stored in a light-transmitting synthetic resin container and stored under severe light irradiation conditions, and to provide flavor and physical properties. It is an object of the present invention to provide a fermented milk and a fermented milk product which do not deteriorate.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, when producing a fermented milk product filled in a light-permeable container, the fermented milk By adding thiols or natural products containing thiols to thiols or cysteine or natural products containing cysteine, light resistance of bacteria, that is, survival of bacteria at the time of light irradiation,
It has been found that the effect of suppressing the deterioration of the flavor of the product can be improved. It has also been found that the addition of vitamin C, bayberry extract, rutin, fruit juice and the like can further increase the light fastness of the bacteria.

The present invention has been completed based on these findings, and an object of the present invention is to provide fermented milk containing thiols or natural products containing thiols.

Another object of the present invention is to provide fermented milk characterized in that the thiols or natural products containing thiols are cysteine or natural products containing cysteine.

Still another object of the present invention is to provide a fermented milk wherein the fermented milk further contains one or more substances selected from vitamin C, bayberry extract, rutin and fruit juice. It is.

Still another object of the present invention is to provide a fermented milk product obtained by filling the above fermented milk in a light-permeable container.

Still another object of the present invention is to provide a light-resistant fermented milk and a light-resistant fermented milk product, wherein the fermented milk and the fermented milk product have light resistance, and a method for producing the same. Things.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, fermented milk refers to lactic acid bacteria in a solution of milk products such as milk and goat milk, skim milk powder, whole milk powder and fresh cream, either as such or diluted as necessary. This is a cultured solution, which includes fermented milk specified by a ministerial ordinance such as milk, lactic acid bacteria beverages for dairy products, and beverages containing live bacteria such as lactic acid bacteria beverages.

The lactic acid bacteria to be inoculated into dairy products or the like to prepare the fermented milk are not particularly limited, and Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus gasseri, Lactobacillus zeae, Lactobacillus johnsonii, Lactobacillus delbrucii subspecies Bulgaricus, Lactobacillus delbruchy subspecies subspecies delbrukki etc., Streptococcus genus bacteria such as Streptococcus thermophilus, etc., Lactococcus lactis, Lactococcus plantarum, Lactococcus rafinocactus Lactococcus spp., Leuconostoc mesenteroides, Leuconostoc spp.
Any of Leuconostoc spp. Bacteria such as lactis and Enterococcus spp. Bacteria such as Enterococcus faecalis and Enterococcus faecium can be preferably used.
These can be used alone or in combination of two or more. Among them, selected from Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus delbruchy subspecies Bulgaricus, Lactococcus lactis and Streptococcus thermophilus When lactic acid bacteria are used, particularly excellent improvement in light resistance is obtained, which is preferable.

In the preparation of the fermented milk of the present invention, a bacterium belonging to the genus Bifidobacterium such as Bifidobacterium breve, Bifidobacterium bifidum or Bifidobacterium longum may be used together with lactic acid bacteria. Good. These can also be used alone or in combination of two or more.

The thiols used as the light-fast component in the present invention are compounds containing SH groups.
Specific examples include cysteine, glutathione, mercaptoethanol, dithiothreitol and the like. These may be those isolated from synthetic or natural products, but yeast extracts containing thiols or derivatives thereof,
It can be used as a natural product such as a meat extract.

The amount of the thiols or natural products containing the thiols is not particularly limited, but is 0.0 as thiol.
02% by mass to 0.05% by mass (hereinafter simply referred to as%)
Is particularly preferable, and 0.002% to 0.04% is particularly preferable.
Furthermore, 0.005 to 0.01% is preferable. If the content is less than 0.002%, a sufficient effect of improving light resistance (including the effect of suppressing flavor deterioration) cannot be obtained. If the content is more than 0.05%, the specific bitterness is so strong that the flavor is unfavorably deteriorated.

Among the thiols, cysteine is the most preferable in terms of the flavor and light resistance of fermented milk.
The cysteine may be any of L- or D-cysteine obtained by chemical synthesis, L-cysteine derived from natural products, and the like, and can be suitably used in the form of a hydrochloride. At the time of use, cysteine may be added to fermented milk as it is, or may be used together with an emulsifier or a flavor, or mixed with fruit juice or sugar. In particular, apple juice, lemon juice, orange juice, grapefruit juice, strawberry juice, grape juice, and the like, when used in combination with juice, the light fastness of lactic acid bacteria is further improved, and the fermented milk flavor is also improved. Lemon juice,
Warm color juice such as grapefruit juice is preferred. The amount of fruit juice may be appropriately set in consideration of the taste, stability of physical properties, and the like.

When cysteine derived from a natural product is used, the natural product may be used as it is or an extract,
It may be used as a concentrate, a dried product or the like.

In addition to the above-mentioned juice, vitamin C, as well as the above-mentioned fruit juice, can be used as a light fastness improving component which can obtain a better survivability improving effect when used in combination with thiols such as cysteine.
Examples include antioxidants such as bayberry extract and rutin. One or more of these can be used in combination with cysteine or a natural product containing cysteine.
Examples of vitamin C include ascorbic acid and inorganic salts of ascorbic acid (eg, sodium ascorbate,
Alkali metal ascorbate such as potassium ascorbate, alkaline earth metal ascorbate such as calcium ascorbate and magnesium ascorbate,
And ammonium salts of ascorbic acid (eg, arginine salt, histidine salt, triethanolamine salt, meglumine salt, etc.). Among them, preferred is a high survivability improving effect when ascorbic acid is used in combination. . The bayberry extract is a component contained in a component obtained by extracting the bark of bayberry with an organic solvent such as water or alcohol, and is a solid obtained by drying the extracted solution as it is or by freeze-drying or the like. Can be used.

The amount of these additives is not particularly limited. However, from the viewpoint of effects and taste, if vitamin C is 0.001.
% To about 0.5%, particularly 0.005% to 0.04%, and for a bayberry extract (dry weight) and rutin, 0.01% to 0.1%, particularly 0.02% to 0.09% is preferred.

The production of the light-resistant fermented milk of the present invention is carried out except that thiols or natural products containing thiols or fruit juice, vitamin C, bayberry extract, rutin, etc. are added at any stage of the production. It can be carried out by a conventional method. For example, a skim milk solution is first sterilized, and then lactic acid bacteria and bacteria of the genus Bifidobacterium are inoculated and cultured, and this is homogenized to obtain fermented milk. Fermentation method,
The conditions and the like may be ordinary conditions, and are not particularly limited. For example, in the case of Lactobacillus casei, the bacteria may be inoculated into a medium containing dairy products and cultured at about 35 ° C. to a pH of about 3.5 to 4.5. In the case of Bifidobacterium breve, the dairy product may be cultured at about 37 ° C. for about 20 to 22 hours and at a pH of about 4.5 to 4.7 after inoculation. As a culture method, a method suitable for culture of a microorganism using static culture, stirring culture, shaking culture, aeration culture, or the like may be appropriately selected and used.

On the other hand, the addition of thiols or natural products containing thiols, or fruit juice, vitamin C, bayberry extract, rutin, etc., used before or after fermentation (cultivation) of lactic acid bacteria It may be. These additions, for example, may be added and mixed as a syrup solution containing a thiol or a thiol-containing natural product or other additives prepared separately, and then a flavor may be added to finish the final product. it can. Further, various thickeners such as agar and gelatin may be prepared in a syrup solution or separately as a thickener, and then added to obtain a solid light-resistant fermented milk.

Further, the light-resistant fermented milk of the present invention may optionally contain other food materials, that is, various sugars, emulsifiers, thickeners, sweeteners, sour agents, fruit juices and the like. Specifically, sucrose, isomerized sugar, glucose, fructose, palatinose, trehalose, lactose, sugars such as xylose, sorbitol, xylitol, erythritol,
Emulsifiers such as lactitol, palatinit, reduced starch syrup, reduced maltose syrup, etc., emulsifiers such as sucrose fatty acid ester, glycerin sugar fatty acid ester, lecithin, thickening (stabilizing) agents such as carrageenan, guar gum, xanthan gum, pectin, and locust bean gum; Is mentioned. In addition, even if various vitamins such as vitamin A and vitamin B, and minerals such as calcium, iron, manganese, and zinc are blended, light-resistant fermented milk having excellent flavor can be obtained.

The light-resistant fermented milk of the present invention thus obtained can be made into any type of product such as plain type, flavored type, fruit type, sweet type, etc. The product can be in any form such as a soft type, a drink type, a solid (hard) type, a frozen type, and the like.

The above-mentioned light-resistant fermented milk of the present invention can be filled in a light-permeable container to obtain a light-resistant fermented milk product. The light transmissive container is a container having a light transmittance of more than about 20%, and examples thereof include a container molded of glass or a synthetic resin material. Specific examples of the synthetic resin material include polystyrene, polyethylene, vinyl chloride, and polyethylene terephthalate.Of these, inexpensive and excellent in moldability and safety are polystyrene and polyethylene, and in particular, Polystyrene has good moldability.

The light transmittance of the light-transmitting container is measured by using an integrating sphere light transmittance measuring device, passing light emitted from a light source through a test piece (container), and receiving the transmitted light. It is performed by measuring with a machine. The principle of this measurement method is “JI
S Handbook 11 Plastics "(Japanese Standards Association, issued on April 20, 1987), pp. 253 to 255, and commercially available integrating sphere type light transmittance measuring devices include: There are a haze meter (manufactured by Nippon Zenki Co., Ltd.) and a haze meter (manufactured by Toyo Seiki Co., Ltd.), and these can be used.

The reason why the number of lactic acid bacteria decreases when the fermented milk is irradiated with light, which is a problem in the present invention, and the color of the fermented milk fades is not yet clear. You can find out as follows.

That is, first, fermented milk is filled in a polystyrene container, and various substances are added thereto, followed by sealing to produce a fermented milk product. At this point, the number of viable bacteria in the fermented milk product is determined. Next, the fermented milk product is irradiated with light at an illuminance of 2000 lux for 168 hours using a light stability tester (LST-300: manufactured by Tokyo Rika Instruments), and the viable cell count is measured again. From the viable cell count before and after the light irradiation, the survival rate (survival rate) of the lactic acid bacteria was calculated according to the following formula, and this value was compared with a control product that was subjected to the same operation without adding any special compound. It is checked by comparison.

[0030]

(Equation 1)

In the present invention, the light-resistant fermented milk product is
A dairy product in which the survival rate of lactic acid bacteria in fermented milk is at least 5 times that of a control product (fermented milk) containing no special component when irradiated with light for 168 hours at an illuminance of 2000 lux. In particular, a survival rate of 10 times or more is preferable because a high viable cell count can be maintained even under poor conditions, and more preferably 50 times or more. As shown in Examples below,
From the above formula, thiols, particularly cysteine, are selected as those capable of imparting an excellent light resistance when added to fermented milk, and by using them together, an extremely excellent light resistance can be provided. The substances are fruit juice, vitamin C, bayberry extract and rutin.

[0032]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.

Example 1 Light fastness test of fermented milk supplemented with thiols and β-carotene: Lactobacillus casei YIT9029 strain 0.1 in a medium containing 20% skim milk powder and 1% glucose.
% Inoculated and cultured at 37 ° C. for 3 days to obtain fermented milk.

20 ml of the obtained fermented milk was filled in a 50 ml glass bottle, and cysteine hydrochloride monohydrate (manufactured by Nacalai Tesque), glutathione (Tokyo Kasei), mercaptoethanol (manufactured by Wako Pure Chemical Industries), dithiothrei Thor (manufactured by Wako Pure Chemical Industries, Ltd.) and an extracted carotene emulsion containing 2% β-carotene (water-soluble biocarotene; manufactured by Kyowa Hakko Co., Ltd.) are each diluted with distilled water to 1% and sterilized by filtration. Are added to the fermented milk at the concentrations shown in Table 1, respectively.
Fermented milk to which thiols and β-carotene were added was obtained.

After measuring the viable cell count of the fermented milk thus obtained, a light irradiator (manufactured by Nippon Rika: L
ST-300), and irradiated at 10,000 lux for 24 hours. Then, the viable cell count was measured again and compared with the viable cell count before light irradiation. Table 1 shows the results.

(Results)

[Table 1]

As shown in Table 1, the addition of thiols and β-carotene to fermented milk suppressed a decrease in the number of lactic acid bacteria due to light irradiation, and the effect of cysteine was particularly good.

Example 2 Light fastness test based on cysteine concentration: The effect of cysteine was found to be remarkable from Example 1. Next, the effect when the concentration of cysteine was changed was confirmed.

Skim milk powder solution (solid content 15.2%, fat 0.2%)
(2%, protein 5.7%) at 121 ° C. for 3 seconds. Separately, an inoculum of Lactobacillus casei YIT9029 was produced, and this was added to the above skim milk solution at a concentration of 0.5%.
It was cultured to H3.6 to obtain fermented milk.

After homogenizing the obtained fermented milk at 150 kg / cm ² , it was mixed with a syrup solution containing sucrose (final concentration: 0.2%) and cysteine at the concentrations shown in Table 2, and further mixed with yogurt flavor (Yakult Material Co., Ltd.). Made alone (0.
08%) and filled in a polystyrene container to obtain a drink yogurt type fermented milk (Products 1 to 3). On the other hand, a fermented milk product produced using a syrup containing only sucrose was used as a control.

After measuring the viable cell count of the drink yogurt type fermented milk product thus obtained, the temperature in the refrigerator was reduced to 1
After placing in a light irradiator at 0 ° C. and irradiating at 2,000 lux for 168 hours, the viable cell count was measured again to determine the survival rate. Under the same conditions, the survival rate was determined for the samples that were not irradiated with light. Table 2 shows the results.

[0042]

[Table 2]

As a result, it was found that by adding 0.005% or more of cysteine to the drink yogurt, a decrease in the number of viable cells due to light irradiation can be suppressed.

Example 3 Test of change in light resistance and flavor by addition of cysteine: The formulation, production method, light irradiation conditions, etc. of fermented milk products were the same as in Example 2 except that the following substances were used as additives. And In addition, the evaluation of the flavor after irradiation was performed by sensory evaluation of five specialized panelists using the following indices as criteria. Product 4: Cysteine (0.002% final concentration) was added along with 5 times the amount of yogurt flavor. Product 5: Cysteine (final concentration 0.01%) was added together with twice the amount of yogurt flavor. Product 6: Cysteine (0.002% final concentration) was mixed and added to a 50-fold amount of apple juice. Product 7: Cysteine (final concentration 0.01%) was mixed with and added to a 50-fold amount of apple juice. Product 8: Cysteine (final concentration 0.002%) was mixed with 50 volumes of lemon juice and added. Product 9: Cysteine (final concentration 0.01%) was mixed and added to 50 times the volume of lemon juice. Product 10: Cysteine (0.002% final concentration) was mixed and added to 50 times the volume of orange juice. Product 11: Cysteine (final concentration 0.01%) was mixed with and added to a 50-fold amount of orange juice.

<Flavor Evaluation Criteria> Evaluation: Contents +2: Good taste (no deteriorating odor) +1: Moderately good (weak deteriorating odor) 0: Normal -1: Somewhat bad taste (deteriorating odor) (Slightly strong) -2: Bad taste (strong deterioration odor)

[0046]

[Table 3]

As shown in Table 3, cysteine provided good light fastness (effect of suppressing flavor deterioration) regardless of the administration form. In particular, when mixed with fruit juice, both light resistance and flavor were good.

Example 4 Test of change in light fastness and flavor when cysteine and an antioxidant are combined: skim milk powder solution (solid content: 15.2)
%, Fat 0.2%, protein 5.7%) were sterilized at 121 ° C. for 3 seconds. Separately, Lactobacillus casei YIT9029
Of the above-mentioned skim milk powder solution, and
The mixture was added and cultured to pH 3.6 to obtain fermented milk.

The obtained fermented milk was homogenized at 150 kg / cm ² , mixed with a syrup solution containing sucrose (final concentration: 0.2%) and each of the substances shown in Table 4, and further mixed with yogurt flavor (Yakult Material Co., Ltd.). Made (0.08
%) And filled in a polystyrene container to obtain a drink yogurt-type fermented milk (products 12 to 20). On the other hand, a fermented milk product produced using a syrup containing only sucrose was used as a control.

After measuring the viable cell count of the drink yogurt type fermented milk product thus obtained, the temperature in the refrigerator was reduced to 1
After placing in a light irradiator at 0 ° C. and irradiating at 2,000 lux for 168 and 336 hours, the viable cell count was measured again to determine the survival rate. In addition, sensory evaluation was performed in the same manner as in Example 3.
Table 4 shows the results.

[0051]

[Table 4]

As a result, it was found that a synergistic effect was obtained by combining cysteine with another antioxidant. In particular, it was found that the effect was high when combined with vitamin C.

Example 5 Light fastness and flavor change test when cysteine and vitamin C are combined: skim milk powder solution (solid content 15.2)
%, Fat 0.2%, protein 5.7%) were sterilized at 121 ° C. for 3 seconds. Separately, Lactobacillus casei YIT9029
Of the above-mentioned skim milk powder solution, and
The mixture was added and cultured to pH 3.6 to obtain fermented milk.

After homogenizing the obtained fermented milk at 150 kg / cm ² , it was mixed with a syrup solution containing sucrose (final concentration: 0.2%) and the amounts of cysteine and vitamin C shown in Table 5,
Furthermore, yogurt flavor (manufactured by Yakult Material Co., Ltd.) was added alone (0.08%) and filled in a polystyrene container to obtain fermented milk of a drink yogurt type (products 21 to 37). On the other hand, a fermented milk product produced using a syrup containing only sucrose was used as a control.

After the viable cell count of the drink yogurt type fermented milk product thus obtained was measured, the temperature in the refrigerator was reduced to 1
After placing in a light irradiator at 0 ° C. and irradiating at 2,000 lux for 168 and 336 hours, the viable cell count was measured again to determine the survival rate. In addition, sensory evaluation was performed in the same manner as in Example 3.
Table 5 shows the results.

[0056]

[Table 5]

As a result, 0.002% or more of cysteine and 0.01% or more of vitamin C are added to the drink yogurt (particularly, 0.006 to 0.01% of cysteine and 0.01 to 0.04% of vitamin C). It was found that the addition can significantly reduce the number of viable bacteria and the deterioration of flavor due to light irradiation.

[0058]

According to the present invention, one or two selected from cysteine and vitamin C, bayberry extract, rutin and fruit juice are added to fermented milk filled in a light-permeable container.
By adding more than one kind of material, it is possible to prevent a decrease in the number of bacteria and deterioration of flavor due to light irradiation.

Accordingly, this fermented milk can be filled into a light-permeable container to form a light-resistant fermented milk product, and can be used in a place exposed to sunlight or a place continuously exposed to strong illumination such as a showcase. It can prevent a decrease in lactic acid bacteria and does not lose the original function of the fermented milk product. that's all

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshinori Abe 1-1-19 Higashi-Shimbashi, Minato-ku, Tokyo Yakult F-term (reference) 4B001 AC05 AC31 AC35 AC36 AC99 BC01 BC14 DC01 EC99

Claims (9)

[Claims] 1. Fermented milk containing thiols or natural products containing thiols. 2. The fermented milk according to claim 1, wherein the thiols or natural products containing thiols are cysteine or natural products containing cysteine. 3. The fermented milk according to claim 1 or 2, further comprising one or more substances selected from vitamin C, bayberry extract, rutin and fruit juice. . 4. The fermented milk according to any one of claims 1 to 3, wherein the fermented milk has light resistance. 5. A light-resistant fermented milk product obtained by filling the fermented milk according to any one of claims 1 to 4 in a light-permeable container. 6. The light-resistant fermented milk product according to claim 5, wherein the light-transmitting container has a light transmittance of 20% or more. 7. The light-resistant fermented milk according to claim 5, wherein the light-transmitting container is made of one or more materials selected from polystyrene, polyethylene, vinyl chloride, and polyethylene terephthalate. Product. 8. The survival rate of lactic acid bacteria in fermented milk when illuminating at 2,000 lux for 168 hours is as follows:
The light-resistant fermented milk product according to any one of claims 5 to 7, which is 50 times or more the amount of fermented milk not containing cysteine or a natural product containing cysteine. 9. A lactic acid bacterium is inoculated into a medium mainly composed of milk,
After culturing to produce fermented milk, filling the fermented milk in a light-permeable container, and then in a method for producing a fermented milk product that seals the container, before or after culturing the lactic acid bacterium, adding a natural product containing cysteine or cysteine. A method for producing a light-resistant fermented dairy product, comprising: