KR20010026148A - Frozen soy yogurt and process of preparation therefor - Google Patents

Abstract

PURPOSE: A preparation of soy yogurt using inexpensive and nutritious soy beans is provided to get an improved quality of frozen soy yogurt used as a substitute for dairy goods. CONSTITUTION: The method includes the steps of: (i) sterilizing frozen soy yogurt base including 10% of a solution of isolated soy protein by treating with enzyme, 4% of soybean oil and 0.5% of monoice, and 8% of isomalto oligosaccharides at 121deg.C under pressure for 15min and mixing together; (ii) cooling the mixture to a temperature of 37deg.C and adding 0.02% of vitamin C the cooled mixture; (iii) inoculating 1% of bifidobacterium bifidum to the mixture and fermenting at 37deg.C; and then (iv) storing the fermented yogurt at 4deg.C and mixing the frozen yogurt with 0.04% of aspartame and 0.1% of vanilla essence and getting a soft type of frozen soy yogurt.

Description

Frozen yogurt substitute for dairy products and its manufacturing method {Frozen soy yogurt and process of preparation therefor}

The present invention relates to a frozen soy yogurt for dairy substitutes and a method for producing the same. More specifically, the present invention relates to a frozen yoghurt and a method for producing the same, which are fermented with Bifidobacteria by adding oligosaccharides to the soybean protein which has been removed soybeans by enzymatic treatment and has improved foamability.

Frozen yogurt is a lactic acid bacterium fermented frozen food that combines the nutritional characteristics of yogurt with the characteristics of ice cream. It was first developed by HPFood in 1972 (Knupp, JR: Frozen yogurt. Cult. Dairy Prod. J. 14 (5), 16 (1979); Mann, EJ: Frozen yogurt. Dairy Industries International. 42, 21 (1977). Frozen yogurt is a natural food that contains little artificial preservatives or synthetic additives. It is a low-fat, low-calorie food that provides about 100 kcal of calories per 100g, and has a lactose content of 30 or more compared to ice cream. It is being reduced, making it a useful food for people who are lactose intolerant (Anon: Frozen Yogurt-Delicacy of the decade? The Milk Industry; 8, 21 (1997)). In the West, frozen yogurt products have been actively developed since the mid-1970s, and consumer preferences have continued to increase. Nevertheless, frozen yogurt still has a problem that its product standards are not clear, and moreover, there is still a lack of information and recognition in Korea.

The most important factor affecting the quality of frozen yogurt is the type of lactic acid bacteria used (Rasic, J. L., and J. A. Kurmann. Yogurt. 37 (1978)), because it affects the production of acidity and flavor. Therefore, researches on lactic acid bacteria have been actively conducted, and since 1990s, interest in bifidus bacteria has increased especially. Bifidus bacteria produce organic acids during fermentation, lowering the pH of the intestine, inhibiting the growth of harmful bacteria that are sensitive to acids, and intestinal intestinal function, and are particularly effective for intractable diarrhea in infants and constipation in adults. In addition, Bifidobacteria has been reported to have anti-cancer effects and lower serum cholesterol (Hughes, D. B. and Hoover, D. G .: Bifidobacteria. Their potential for use in American dairy products. Food Technol, 54, 4 (1991)). Despite such evidence that Bifidobacteria is beneficial to health, Bifidobacteria is limited in its use in the food industry due to the complicated conditions of nutritional requirements and anaerobic culture.

On the other hand, oligosaccharide is a representative bifidus growth promoting factor in fermented foods, which is not well metabolized in the body, which is low in calories, prevents tooth decay, and improves constipation (Lee Hyun-soo: Oligosaccharide's function and use in food. (1994)).

In addition, soybean is a high-quality vegetable protein food with high nutritional value, and effectively replaces animal protein in many cases for reasons of physiological function, food functional characteristics, economic feasibility, and variety of uses. However, soy protein is restricted in its use because of its unique soybean scent. When used in food, protein drinks, ice cream, and other processed products have been developed by reducing soybean scent and improving its functionality by enzyme treatment and fermentation method. come. However, until now, little research has been made to replace soy protein with soy protein in frozen yogurt, a type of lactic acid bacteria fermented frozen food.

The present inventors have been able to complete a new type of bifidus fermented frozen yogurt replacing milk protein with soy protein by noticing the frozen yogurt using the vegetable soy protein despite its excellent nutritional value.

Accordingly, it is an object of the present invention to provide frozen yogurt fermented with soy protein and replaced with soy protein.

In addition, another object of the present invention to provide a method for producing the soy protein frozen yogurt.

In accordance with the above object, in the present invention, soy protein yogurt and method for preparing the soybean protein which are fermented and frozen by Bifidobacteria by adding oligosaccharides to soy protein with improved soybean protein using an enzyme-treated soy protein (SPI) To provide.

Hereinafter, the present invention will be described in more detail.

Figure 1 shows the overrun change over time of frozen soy yogurt prepared by different starter cultures during operation for 30 minutes in an ice cream maker,

Figure 2 shows the change in the melt-down quality of frozen soy yogurt prepared by different starter cultures and oligosaccharides for 60 minutes at room temperature over time.

Oligosaccharides were added to the enzyme-treated soybean protein and fermented into three bifidus bacteria. PH, acidity, viable cell count, acid resistance, and viscosity of the prepared soy protein yoghurt were measured, and the overrun, melt-down, and freezing count of frozen soy protein yoghurt prepared by freezing them. And sensory characteristics were measured.

As a result, pH and acidity of soy protein yogurt showed significant difference according to the type of strain, showing the highest pH in B. bifidum cultures and the lowest in B. intiantis. Acidity showed the opposite trend. The number of viable cells showed a slight change depending on the type of strain, but all samples contained more than 10 ⁹ CFU / ml. In addition, the acid resistance of bifidus bacteria contained in soy protein yogurt was found to be relatively good because it showed more than 10 ⁸ CFU / ml in all strains. Viscosity was significantly different according to the strains. B. bifidum culture group had the highest viscosity and B.infantis culture group had the lowest viscosity. The overrun was highest in the B. bifidum culture group and the lowest in the B.infantis culture group, depending on the strain. The degree of melting showed the opposite trend.

After the frozen yogurt was frozen in the ice cream maker for 30 minutes, the viable cell count was higher than 10 ⁹ CFU / ml, similar to the initial viable cell number. The soybeany was weakly detected without any significant difference between samples and the degree of sourness and sweetness was evaluated as palatability. Significant differences were observed according to the strains. infantis) The culture group was poorly evaluated. The bitter taste was evaluated to be weak in the B. bifidum culture group and the B. breve culture group, with no significant difference. The B.infantis culture group was evaluated to be bitter. . In mouth texture, B. bifidum culture group was generally evaluated as good, followed by B.breve culture group and B.infantis culture group. . Overall preference was favorably assessed by the B. bifidum culture group. On the other hand, most of the items did not show a significant difference according to the type of oligosaccharides.

Hereinafter, the present invention will be described in more detail with reference to Examples. The following examples are merely to illustrate the invention, but not to limit the scope of the invention.

Example 1 Preparation of Isolated Soy Protein Frozen Yogurt

1. Material

Isolated soy protein (SPI) was supplied by Supro E500 from Kwangil Co., Ltd. and the alpha-chymotrypsin protein used for enzymatic treatment was from Sigma. The strains used were distributed by Korea Biotechnology Research Institute as B. bifidum ATCC 11863, B.infantis ATCC 15697, and B.breve ATCC 15700. Isomaltooligosaccharides (isomaltooligo-saccharides) was provided by Samyang Genex Research Institute.

2. Frozen Soy Yogurt Manufacturer

Frozen soy yogurt base and isomaltoligosaccharide (8), which is a well-mixed mixture of 10 isolated soybean protein (SPI) enzymes, 4 soybean oils, and 0.5 monoice. ) Were autoclaved at 121 ° C. for 15 minutes and then mixed well. Then, when cooled to 37 ℃ was added to the vitamin C of 0.02 and inoculated 1 (v / v) of each of three kinds of bifidus bacteria and incubated for 16 hours at 37 ℃. At this time, the number of initially inoculated bacteria was 1.6-2.2 X 10 ⁸ CFU / ml. After culturing, the soybean yoghurt was stored at 4 ° C. for 24 hours, followed by 0.04 aspartame and 0.1 vanilla essence, to prepare a soft-type frozen soybean yoghurt using an ice cream maker.

Soybean yogurt prepared by the above method was used as a sample for overrun, melting degree, measurement of changes in viable cell count following freezing, and sensory evaluation.

Example 2 Measurement of pH, Acidity and Viscosity According to Strains Used

1.Measuring method

(1) pH and acidity measurement

The pH of each sample was measured using a pH meter (Metrohm 635), and the acidity was taken with 10 ml of the sample, diluted with the same amount of distilled water, and 0.5 ml of phenolphthalein (indicator) solution was used as an indicator. Neutralization was performed until At this time, the number of ml of 0.1 N NaOH consumed was measured and converted into lactic acid (LA) (Yoo Ju-hyun: Food Engineering Experiment I, Inquiry, 449 (1995)).

(2) viscosity measurement

The viscosity of the sample was determined by the method of Ioanna (Ioanna S. Martinou, Volulaik and Gregory K. Zerfiridis: Effect of some stabilizers on texture and sensory characteristics of yogurt ice cream from sheep's milk, J. Food Sci. 55 (3) , Brookfield viscometer (Model LVF), was measured at 60 rmp for 1 minute at spindle number 3 (spindle No. 3) at 4 ° C.

2. Effect of Different Bifidus on pH, Acidity and Viscosity

Changes in pH, acidity and viscosity according to the use of different bifidus bacteria are shown in Table 1 below.

Starter cultures pH Titrable acidity Viscosity (cp) B.bifidum 5.26 ^a ± 0.27 0.82 ^c ± 0.18 1026.00 ^a ± 83.27 B.breve 4.76 ^b ± 0.02 1.04 ^b ± 0.01 860.00 ^b ± 87.18 B.infantis 4.40 ^c ± 0.06 1.39 ^a ± 0.09 690.00 ^c ± 52.91 F-value 22.21 ^** 18.42 ^** 14.71 ^**

* p <0.05, ** p <0.01, *** p <0.001

^ac) Mean values with different superscripts in the same column indicate significant differences by Duncan's multiple range test (p <0.05).

As shown in Table 1, the significant difference according to the used strain appears, pH is the highest in the B. bifidum culture group and the lowest in the B.infantis culture group, the acidity is the opposite The trend was shown. On the other hand, the viscosity of the B. bifidum culture group was the highest, and the viscosity of the B. intiantis (B.infantis) culture group was the lowest. When frozen the B. bifidum culture group showed the highest viscosity in this Example, the texture in the mouth was also well evaluated when the sensory evaluation of Example 7 below.

Example 3 Measurement of Viable Cell Number and Acid Resistance According to Strains

1. Measurement Method

(1) viable cell count

1 g of the sample is aseptically taken, diluted by 10-fold dilution with sterile peptone water, plated on Lactobacillus MRS medium, and then plated on Lactobacillus MRS medium using an anaerobic jar (Difco) at 37 ° C. After 48 hours of anaerobic incubation at 25 to 250 colonies were selected by selecting the plate appears. In addition, the soybean yoghurt fermented at 37 ° C. for 16 hours with B.infantis was measured for 7 days at 4 ° C., and the number of viable cells was measured and compared with the initial viable count.

(2) acid resistance measurement

Verada et al. (Berrada, N., JF Lemeland, G. Laroche, O. Thouvenot, and M. Piaia .: Bifidobacteroium from fermented milks; Survival during gastric transit. J. Dairy Sci. 74, 409 ( 1991)) was adjusted to pH 3.0 by adding 1.25N hydrochloric acid (HCl) to soybean yogurt containing bifidus bacteria and incubated for 90 minutes at 37 ℃. The bacterial count at this time was measured and compared with the initial viable count of soybean yoghurt.

2. Results

There was a slight difference in the number of viable cells according to the strain, but all samples showed a viable cell number of 10 ⁹ CFU / ml or more, which was suitable for the component specification of yogurt. On the other hand, when soybean yogurt was ingested, the viability of bifidus bacteria in human stomach was indirectly measured, but all strains were lower than the initial viable cell count, but showed more than 10 ⁸ CFU / ml, which was relatively excellent in acid resistance. The total number of viable cells after incubating the bifidus bacteria in soybean yoghurt at 37 ° C. for 16 hours and the change in viable cell numbers after incubation at pH 3.0, 37 ° C. for 90 minutes in soybean yogurt are shown in Table 2 below.

Starter cultures Total viable count (CFU / ml) Viable cell count change (CFU / ml) B.bifidum 1.87 X 10 ⁹ ± 1.6 X 10 ⁸ 3.02 X 10 ⁸ ± 3.6 X 10 ⁷ B.breve 3.12 X 10 ⁹ ± 9.0 X 10 ⁷ 4.53 X 10 ⁸ ± 4.2 X 10 ⁷ B.infantis 3.17 X 10 ⁹ ± 4.0 X 10 ⁷ 2.70 X 10 ⁸ ± 1.4 X 10 ⁷

Berada, et al. (Berrada, N., JF Lemeland, G. Laroche, O. Thouvenot, and M. Piaia .: Bifidobacteroium from fermented milks; Survival during gastric transit.J. Dairy Sci. 74, 409 (1991) ) Reported that bifidus bacteria to be used in fermented milk production should be used for fermented milk consumption only when strains with excellent acid resistance were used.

Example 4 Comparison of Overruns According to Strains

1. Overrun measurement

The overrun measurement of the sample was performed by Ioanna's method (Ioanna S. Martinou, Volulaik and Gregory K. Zerfiridis: Effect of some stabilizers on texture and sensory characteristics of yogurt ice cream from sheep's milk, J. Food Sci. 55 (3). ), 703 (1990)). Every five minutes during the operation of the ice cream maker, the sample taken out of the maker was put in a 200ml cup and weighed and calculated using the following equation.

2. Change of overrun according to strain

The change over time of the overrun of frozen soy yoghurt prepared by different strains during 30 minutes of operation in an ice cream maker is shown in FIG. 1.

During the initial 5 minutes, the overrun of the B. bifidum culture group was slightly higher than that of the B. breve and B.infantis culture groups, but there was no significant difference. However, as the operating time in the ice cream maker increased, the overrun increased relatively slowly and showed significant difference, and all samples reached the highest level with 20 minutes of operation. At this time, the overrun of each sample was the highest in the B.bifidum culture group (37.3 ~ 42.2), and the B.breve culture group was 32.7 ~ 36.0 and the Bifidium Infantis (B. infantis) culture group was low (32.5-34.5).

Example 5 Measurement of Melt-Down

1. Measurement Method

Melting degree was measured according to the method of Shin and Yoon (Shin, Won-Seon, Yoon-Seon: Effect of stabilizer on the texture of frozen yogurt, Journal of the Korean Culinary Science, 12 (1), 20 (1996)). On top of the measuring cylinder, a young wire mesh is placed, followed by ice cream scooper frozen yogurt. Over time, the amount of melting to the bottom of the measuring cylinder was calculated as a percentage per dose of scoop and the appearance of the melted yogurt mix was observed.

2. Comparison of the degree of melting according to the strain

Figure 2 shows the change over time of the melting of frozen soy yogurt prepared for 60 minutes at room temperature using different strains and oligosaccharides.

There was no significant difference in the degree of melting between samples during the first 10 minutes, but showed significant difference over time, and after 60 minutes, the degree of melting of the B.infantis culture group was the largest. The degree of melting of the B.breve culture group was significantly less than that of the B.infantis culture group, and the B.bifidum culture group had the least amount of melting. However, solids and water were separated from the melted mix. In this example, it can be seen that the degree of melting of the sample has an inverse correlation with the overrun.

Example 6 Change of Viable Cell Number by Freezing

1. Measurement of viable cell count following freezing

After soybean yoghurt was operated for 30 minutes in an ice cream maker, 1g of sample was aseptically taken, diluted by 10-fold dilution with sterile peptone water, smeared on Lactobacillus MRS medium, and then using an anaerobic incubator (anarobic jar (Difco)). Anaerobic incubation at 37 ° C. for 48 hours was performed by selecting plates with 25 to 250 colonies. This was compared with the initial viable count of soy yogurt.

2. Variation of viable counts according to strains

The change in viable cell number of bifidus bacteria after freezing for 30 minutes in the ice cream maker is shown in Table 3 below.

Freezing time (minutes) Strain B.bifidum (CFU / ml) B.breve (CFU / ml) B.infantis (CFU / ml) 0 1.87X10 ⁹ ± 1.6X10 ⁸ 3.12X10 ⁹ ± 9.0X10 ⁷ 3.17X10 ⁹ ± 4.0X10 ⁷ 30 1.05X10 ⁹ ± 2.3X10 ⁸ 1.12X10 ⁹ ± 3.6X10 ⁸ 1.41X10 ⁹ ± 1.8X10 ⁸

Ray, B., and RL, Bredley .: Effects on freezing points of carbohydrates commonly used in frozen diets.J. Dairy Sci., 66 (1983), because microorganisms are very sensitive to freezing. Frozen yogurt showed a slight decrease in lactic acid strain. In this example, as shown in Table 3 above, the resistance to freezing was maintained by maintaining at least 10 ⁹ CFU / ml similar to the initial viable count.

Example 7: sensory evaluation

1. Sensory evaluation

For the sensory evaluation, the prepared frozen soy yoghurt was stored for 72 hours in a freezer at -18 ° C. and then melted at 4 ° C. for 1 hour. The sensory tester consisted of 15 graduate students from Chung-Ang University. Explain the purpose of the experiments and train them to become familiar with the sensory evaluation methods performed in this experiment, and then use a five-point grading method for soybean odor, sour taste, sweetness, bitter taste, texture in the mouth, melting degree, and overall preference. Sensory evaluation was performed.

2. Sensory Evaluation Results

Sensory evaluation results of frozen soy yogurt prepared by different strains are shown in Table 4 below.

Item Fishy Sour taste sweetness bitter Texture in the mouth Melting degree Overall preference DM 3.8 4.1 ^a 4.5 ^a 3.9 ^a 3.6 ^a 2.8 4.3 ^a VM 3.3 2.9 ^b 2.7 ^b 3.2 ^a 2.4 ^b 3.1 2.6 ^b IM 3.6 1.7 ^c 1.3 ^c 2.1 ^b 1.9 ^bc 2.6 1.6 ^c F-value 0.72 ^NS 16.61 ^*** 48.61 ^*** 6.05 ^*** 10.39 ^*** 0.47 ^NS 22.73 ^***

DM: B.bifidum + isomaltooligosaccharides,

VM: B.breve + isomaltooligosaccharides,

IM: B.infantis + isomaltooligosaccharides

* p <0.05, ** p <0.01, *** p <0.001, NS: Not Significant

^ac) Means with different superscripts in the same column indicate significant differences by Duncan's multiple range test (p <0.05).

The soybean salt was generally weak without any difference between samples, and the degree of sour and sweet taste was evaluated as palatability, and the difference was obvious according to the type of strain. B. bifidum culture group was best evaluated. The B. intiantis culture group was poorly evaluated. In bitterness, B. bifidum and B. breve culture groups were evaluated to be relatively insignificant, but B.infantis was used. The texture in the mouth showed a significant difference according to the type of strains, so that the B. bifidum culture group was most gently evaluated, and the B.infantis culture group was slightly rough. The degree of melting in the mouth was evaluated as normal without significant difference between all samples, and overall preference was significantly different depending on the type of strain. In general, the B. bifidum culture group was preferably evaluated, and Bifidium infantis ( B.infantis) culture group was evaluated as undesirable.

All experiments of the above examples were repeated three times and the average value was shown. The experimental results were analyzed by variance using the SAS package, and the samples with significant differences were tested by Duncan's multiple range test. Significant differences were verified.

The present invention relates to a frozen soy yogurt using 100 soybean protein, which is inexpensive and nutritious as an alternative to dairy products, by enzymatic treatment to improve the functionality and functionality of the isolated soy protein, and determining the bifidus bacteria suitable for frozen soy yogurt production. The frozen soy yogurt produced by the present invention is an invention useful in the food industry because the quality is improved and the palatability is commercialized.

Claims (5)

Frozen soybean yoghurt base containing enzymatically treated 10 isolated soy protein (SPI), 4 soybean oil, 0.5 mono ice and 8 oligosaccharides were mixed by autoclaving, cooled to 37 ° C, and 0.02 vitamin C was added to the mixture. And soybean yoghurt fermented at 37 ° C. by inoculating 1 (v / v) Bifidobacteria, stored at 4 ° C., and frozen frozen soybean yoghurt by mixing 0.04 aspartame and 0.1 vanilla essence. How to Make Soy Yogurt The method of claim 1, wherein the Bifidobacterium is Bifidobacterium bifidum ( B.bifidum ). The method for producing frozen soy yogurt according to claim 1, wherein the autoclaving is carried out at 121 ° C. for 15 minutes. The method of claim 1, wherein the oligosaccharide is isomaltoligosaccharide. Frozen soy yogurt prepared by the method of any one of claims 1 to 4