TWI671013B - Frozen yogurt and method for preparing thereof - Google Patents

Abstract

A yogurt ice cream comprising 10 to 25% by weight of milk, 5 to 20% by weight of Annona muricata pulp, 27% by weight of Yogurt, 12% by weight of sweetener, 13 Eggs by weight and 18% by weight cream. Here, the Soursop fruit in Yogurt ice cream can replace various emulsifiers or stabilizers, so that Yogurt ice cream has a low melting rate, and it can also increase the survival rate and growth rate of probiotics contained in Yogurt ice cream Tolerance to gastric acid and choline, which in turn greatly enhances the nutritional value of yogurt.

Description

Yogurt ice cream and its making method

The invention relates to a food manufacturing technology, in particular to a yogurt ice cream and a preparation method thereof.

Ice cream is a popular food in the society today. According to the definition of the United States Federal Standards (USDA): ice cream should contain at least 10% Milk fat and 20% Total milk solids. In addition to containing general flavors, fat and total milk solids must be indispensable. At 8% and 16%. The total weight of the ice cream and the total food solids are at least 0.54 kg / liter and 0.19 kg / liter, respectively. According to the edible ice factory rules, ice cream foods are defined as: milk or dairy products are the main raw materials, and sugar, emulsifiers, stabilizers, and spices are added to the main raw materials and formulated into a liquid. The liquid is frozen and processed into solid foods such as ice cream, cream, Sherbet, and ice cream. The ice cream has a milk fat of not less than 8% and a total milk solids of not less than 16%; while the snow wave milk component is lower, the milk fat is 1 to 2% and the total milk solids is 2 to 5%. According to the hardness, the types of ice cream can be divided into hard ice cream and soft ice cream. Hard ice cream refers to ice cream generally placed in a freezer, while soft ice cream is ice cream made by omitting the hardening process in the manufacturing process. According to the concentration of specific composition, ice cream can be roughly divided into: frozen casta, original ice cream, flavored ice cream, ice cream, frozen fruit juice, ice products, imitation ice cream and so on. However, generally ice cream has a very high heat content, so low-calorie products such as Yogurt ice cream appear on the market, and gradually replace general ice cream.

Yogurt contains probiotics that are beneficial to the human body, such as lactic acid bacteria, which help to inhibit pathogenic bacteria to maintain the balance of the intestinal flora, promote gastrointestinal health, alleviate breast milk tolerance, and increase the debinding effect of bile salts. And reduce cholesterol, regulate the host's immune system, and anti-tumor. However, during the freezing process of ice cream, the probiotics contained in it may be affected by mechanical damage and solute damage to reduce its survival rate, and even some bacteria are easily frozen due to their own cell morphology, size and other characteristics. Damage or death in the environment.

In one embodiment, a yogurt ice cream may include 10-25% by weight of milk, 5-20% by weight of Soursop fruit pulp, 27% by weight of Yogurt, 12% by weight of sweetener, 13% by weight. Eggs by weight and 18% by weight cream.

In one embodiment, a method for making yogurt ice cream may include mixing eggs and sweeteners into a first mixture, adding milk and cream to the first mixture to mix into a second mixture, and heating the second mixture. 2. Stir the heated second mixture with a conditioning rod for 3 minutes to form a homogeneous substance, mature the homogeneous substance at 4 ° C for 16 hours, add the mangosteen fruit pulp and yogurt to the cooked homogeneous substance to form an ice cream mix, Frozen with ice creamer until the ice cream mix appears thick. In addition, the above ice cream mix has 10 to 25% by weight of milk, 5 to 20% by weight of Soursop fruit pulp, 27% by weight of Yogurt, 12% by weight of sweeteners, and 13% by weight of Egg with 18% by weight cream.

In summary, the yogurt ice cream according to the embodiment of the present invention has an appropriate content of mangosteen fruit pulp, and has good appearance, aroma, flavor and texture. Soursop fruit pulp is rich in polysaccharides, which can reduce the melting rate of Yogurt ice cream itself, so that it has a better taste. In addition, the polysaccharides from the fruit pulp of Soursop can not only prevent the probiotic bacteria in Yogurt ice cream from reducing the survival rate in a frozen environment, but also promote the growth of lactic acid bacteria and increase the number of lactic acid bacteria. Maintains its physiological effects in a high choline environment. Therefore, the Soursop fruit pulp in Yogurt ice cream according to the embodiment of the present invention can provide an effect equivalent to various commercially available emulsifiers or stabilizers, and also enables the ice cream of the embodiment of the present invention to maintain more excellent nutritional properties.

In some embodiments, a yogurt yogurt may include milk, soursop fruit pulp, yogurt, sweeteners, eggs, and cream. And based on the overall weight of Yogurt ice cream, the content of milk is 10% to 25% by weight, the content of Soursop fruit is 5% to 20% by weight, and the content of Yogurt is 27% by weight. The content of the flavor was 12% by weight, the content of eggs was 13% by weight, and the content of cream was 18% by weight.

In some embodiments, the egg may be a whole egg or an egg yolk, and is preferably an egg yolk.

In some embodiments, the content of Soursop fruit pulp in Yogurt ice cream may be 5% to 10% by weight. And, in some embodiments, the content of Soursop fruit pulp in Yogurt ice cream is 5% by weight.

In some embodiments, Yogurt can include at least one type of probiotic bacteria, such as: Lactobacillus acidophilus , Lactobacillus casei , Lactobacillus delbrueckii ssp. Bulgaricus , curved milk Lactobacillus curvatus , Lacobacillus fermentum, Lacobacillus lactis, Lactobacillus plantarum , Lactobacillus reuteri , Lactobacillus bervis , etc. In some embodiments, Yogurt may include Lactobacillus bulgaricus from 9.59 log CFU / ml to 9.67 log CFU / ml and / or Streptococcus thermophilus from 9.70 log CFU / ml to 9.82 log CFU / ml.

In some embodiments, the viscosity of Yogurt ice cream can be from 343 centipoise (cp) to 1422 centipoise.

In some embodiments, the melting rate of the yogurt ice cream may be 0.86 g / min to 1.06 g / min.

Referring to FIG. 1, in some embodiments, a method for making yogurt ice cream may include the following processes. First, the egg and sweetener are mixed into a first mixture (step S11). Next, milk and cream are added to the first mixture and mixed into a second mixture (Sue S12). The second mixture is heated (step S13), and the heated second mixture is stirred with a conditioning rod for about 3 minutes to form a homogeneous material (step S14). The homogenate is aged at 4 ° C. for 16 hours (step S15), and Soursop fruit pulp and yogurt are added to the refined homogenate to form an ice cream mixture (step S16). Finally, the ice cream mixture is frozen with a thawing machine, so that the ice cream mixture has a thick paste shape (step S17).

In some embodiments, the frozen ice cream mix may be hardened at less than or equal to ­20 ° C.

In the following, the technical content and features of the present invention will be described in detail through the listed embodiments in conjunction with the accompanying drawings.

First, the production of yogurt .

Peel the mountain soursop (provided by farmers in Guanziling, Tainan, South) and use a strainer to obtain the fruit. After heating the obtained Soursop fruit pulp at 95 ° C for 10 minutes, it is stored in a freezer for subsequent use. In addition, commercial strains were inoculated into fresh whole milk and fermented to pH 4.5 ± 0.02 at 37 ° C to obtain yogurt.

Next, after mixing the egg yolk liquid with fine sugar, add whole milk and fresh cream and heat to 60 ° C. to mix uniformly. In addition, it was heated at 80 ° C for 10 minutes, and then stirred at high speed for 3 minutes with a hand-held stirring bar (TCY-6709, every source) to form an ice cream mixture. The mixture is cooled and matured at 4 ° C for 16 hours, and then the Soursop fruit pulp and Yogurt prepared through the above process are added to the matured ice cream mixture, and thawed by a fully automatic ice cream machine (282603, Dutch princess). After the ice cream mixture shows a thick paste, it is filled into a suitable container, and then hardened at 20 ° C to obtain a yogurt. The content of each component in Yogurt ice cream is shown in Table 1.

The prepared Yogurt ice cream includes Yogurt ice cream (i.e., the first group) without succulent fruit pulp, Yogurt ice cream (i.e., the second group) with 5% by weight of succulent fruit pulp, and 10% mountain Yogurt ice cream (i.e. group 3) with soursop fruit pulp, Yogurt ice cream (i.e. group 4) with 15% soursop fruit pulp, and Yogurt ice cream (i.e. , Fifth group).

Table 1 ingredient First group Second Group The third group Fourth group Fifth group Whole milk 30 25 20 15 10 Fine sugar 12 12 12 12 12 Egg yolk 13 13 13 13 13 fresh cream 18 18 18 18 18 Yogurt 27 27 27 27 27 Soursop Fruit – 5 10 15 20 (unit:%)

two, Analysis of Yogurt Probiotics.

MRS liquid medium (purchased from American Difco) and M17 liquid culture (purchased from American Difco) were mixed with agar powder to prepare MRS solid medium and M17 solid medium. 1 g of Yogurt obtained from the above process was added to 9 ml of 0.85% (w / v) physiological saline and mixed uniformly, and a 10-fold serial dilution was performed in order to obtain a diluted Yogurt solution. 0.1 ml of diluted Yogurt solution was smeared on MRS solid medium and M17 solid medium, and cultured in a 37 ° C incubator for 48 hours. After the culture is completed, a medium having about 25 to 250 colonies is selected, and the number of lactic acid bacteria and the number of Streptococcus thermophilus bacteria on the medium are calculated. The obtained data is expressed in units of CFU / ml.

Third, the characteristics of Yogurt ice cream.

Analyze the following items for Yogurt Ice Cream (shown in Table 1) of the first to fifth groups to evaluate their physical and chemical properties, stability, antioxidant capacity, and gastric acid resistance of the probiotics contained in them And bile salt tolerance, sensory evaluation of each group of yogurt.

1. PH value:

After the pH meter was calibrated with standard solutions of pH 4.01 and pH 7.01, the pH values of the first to fifth groups of yogurt ice cream were measured.

2. Viscosity:

Take out Yogurt ice cream from the first to fifth groups and melt them into liquids. Take 200 ml of each liquid yogurt ice cream (ie, ice cream syrup), and set the speed at 10 rpm at 5 ° C with a viscometer (Model dv-II, Brookfiled) equipped with a probe No. 2 for each ice cream syrup. Measure viscosity.

3. Expansion rate:

Weigh each of the aforementioned ice cream syrups. After that, each ice cream syrup is frozen back to a solid state, and then each solid yogurt (ie, soft ice cream) is weighed. The expansion ratio of Yogurt ice cream of the first group to the fifth group is calculated by the following Equation 1. Expansion rate = (volume of ice cream slurry of equal weight-volume of soft ice cream of equal weight / volume of soft ice cream of equal weight) × 100% ... (Formula 1).

4. Melting rate:

50 grams were weighed from each of the aforementioned soft ice creams, and transferred into a freezer at a temperature of -20 ° C to harden the soft ice creams into a yogurt ice cream that showed an original state that had not yet melted into ice cream syrup. After the hardening is completed, each group of Yogurt ice cream is melted again in a 25 ° C incubator. Weigh Yogurt in the incubator every 5 minutes. Calculate the melting rate of Yogurt Ice Cream from the first group to the fifth group using Equation 2 below. Melting rate = (weight of yogurt ice cream in the incubator / melting time) ... (Eq. 2).

5. colour:

The color difference meter (NE 4000, Nippon Denshoku Industries) was used to analyze the L ^* value, a ^* value, and b ^* value of the first to fifth groups of yogurt ice cream. The L ^* value represents the brightness of the color, the highest value is 100, and the lowest value is 0. A larger value indicates a brighter color; a positive value of a ^* value represents red, and a negative value represents green; a positive value of b ^* value represents yellow, and a negative value represents blue.

6. Hardness and cohesion:

Place the Yogurt ice cream in the first to fifth groups in an environment at -20 ° C. The hardness and cohesiveness of each group of Yogurt ice cream were tested with a physical property tester (TA.XTplus, Stable Micro Systems) equipped with a probe P10. The test conditions set by the Wujing tester are as follows: the speed before detection (falling speed of the probe P10) is 2 mm / second, the detection speed is 3 mm / second, and the return speed of the probe P10 after detection is 5 mm / second The force applied during detection is 10 grams, and the penetration depth of the probe P10 is 10 mm.

7. Stability of Yogurt Ice Cream:

The Yogurt ice cream of the first group to the fifth group was stored in a freezer at -20 ° C, and the number of lactic acid bacteria and the number of Streptococcus thermophilus were analyzed every 7 days, and continued for 2 months. For each analysis, take 1 gram of Yogurt ice cream from each group and add it to 9 ml of 0.85% sterile physiological saline, mix them evenly and then make a 10-fold serial dilution to obtain a diluted Yogurt ice cream solution. Next, 0.1 ml of diluted Yogurt ice cream solution was smeared on MRS solid medium and M17 solid medium as plates, and cultured in a 37 ° C incubator for 48 hours. After the culture is completed, a medium having about 25 to 250 colonies is selected, and the number of lactic acid bacteria and the number of Streptococcus thermophilus bacteria are counted. The data obtained are expressed in units of CFU / ml.

Furthermore, the Yogurt ice cream of the first group to the fifth group is left at room temperature until it melts into a liquid state, and the liquid yogurt ice cream (ice cream syrup) and acetone are uniformly mixed in a volume ratio of 1: 1. Next, the ice cream syrup / acetone mixed solution was ultrasonically shaken for 30 minutes. Centrifuge at 6000 rpm for 15 minutes, and take the supernatant after centrifugation. Here, an ice cream extract corresponding to each group of yogurt ice cream is obtained.

8. Antioxidant capacity of Yogurt Ice Cream:

Furthermore, 25 microliters of each ice cream extract was taken out, mixed with 1 ml of 2% sodium carbonate, and left in the dark for 2 minutes. Next, add a mixed solution of each ice cream extract and sodium carbonate to 250 microliters of 50% Folin-ciocalteu's phenol reagent (purchased from Sigma-Aldrich) and form a reaction solution in the dark for 30 minutes. The absorbance of each reaction solution was measured with a spectrophotometer (SP-830plus, Metertech) at a wavelength of 750 nm. Gallic acid (purchased from Alfa Aesar) was used as a standard, and different concentrations were prepared as standard curves, and the measured absorbance values were brought into this standard curve. Here, the gallic acid content of total polyphenols in each group of Yogurt ice cream can be obtained. The obtained data is expressed in micrograms of gallic acid equivalent / ml (mg GAE (gallic acid equivalent) / ml) as a unit.

Also, 200 microliters of ice cream extracts were taken from each group of ice cream extracts and mixed with 1 ml of 0.2 mM 2,2-diphenyl-1-picryl-hydrazyl , DPPH) solution was mixed uniformly and left to stand in the dark for 50 minutes to form a reaction solution, and the absorbance of each reaction solution was measured by a spectrophotometer at a wavelength of 517 nm. Here, the free radical scavenging ability of each group of Yogurt ice cream can be calculated by the following formula 3, and the obtained data is expressed as a clearance rate (%).

9. Stomach acid resistance of Yogurt Ice Cream:

The pH of the MRS liquid culture medium was adjusted to 3 with a 1N hydrochloric acid solution, and then sterilized. Next, 1 g of Yogurt ice cream from the first group to the fifth group were respectively added to 9 ml of MRS liquid medium to form a first culture solution, and each first culture solution was cultured at 37 ° C. for 3 hours. After the culture was completed, 100 microliters of the first culture solution was serially diluted, and then the number of lactic acid bacteria and the number of Streptococcus thermophilus bacteria were detected by the plate counting method on the diluted first culture solution.

10. Bile salt tolerance of Yogurt ice cream:

Add 0.4% bile salt to MRS liquid medium and sterilize. Next, 1 g of Yogurt ice cream from the first group to the fifth group were respectively added to 9 ml of MRS liquid medium to form a second culture solution, and each second culture solution was cultured at 37 ° C. for 3 hours. After the culture was completed, 100 microliters of the second culture solution was serially diluted, and the number of lactic acid bacteria and the number of Streptococcus thermophilus bacteria were detected by the plate counting method on the diluted second culture solution.

11. Sensory evaluation of Yogurt Ice Cream:

Sensory evaluation was performed on the first to fifth groups. According to the appearance color, aroma, taste, texture and overall preference of each group of yogurt, the highest score is 9 points.

According to the data obtained in the above experiments, statistical analysis was performed using the Statistical Package for Social Science (SPSS version 19.0), and one-way ANOVA was used to test the differences between the groups. Duncan's multiple rang test was used to compare the significant differences. P <0.05 was considered significant difference.

The experimental results of pH, acidity and color analysis of Yogurt ice cream in each group are shown in Table 2.

Table 2 Group pH value acidity L * a * b * First group 5.23 0.22 68.35 -0.65 9.08 Second Group 5.01 0.23 66.38 -0.81 9.64 The third group 4.85 0.28 66.19 -0.75 10.20 Fourth group 4.64 0.33 63.70 -0.80 10.60 Fifth group 4.54 0.39 60.13 -0.78 11.03

It can be known from Table 2 that the pH value and acidity of yogurt ice cream are affected by the change in the content of the fruit of Soursop. With the increase of the content of Soursop fruit, the pH value of Yogurt ice cream gradually decreased, while the acidity gradually increased.

The color performance of Yogurt ice cream is represented by L * value, a * value, and b * value. L * values represent brightness. The a * value indicates red or green, when a * value is positive, it means red, and when a * value is negative, it means green. The b * value indicates yellow-blue. When the b * value is positive, it means yellow, and when the b * value is negative, it means blue.

In terms of L * value, the L * value of Yogurt ice cream became significantly smaller with the increase in the content of Soursop fruit, indicating that the brightness of Yogurt ice cream decreased with the increase of the content of Soursop fruit. The L * value of the first group was 68.35, and the L * value of the 20% by weight mangosteen fruit pulp (ie, the fifth group) was 60.13, and the decrease was about 12%.

In terms of a * values, the a * values of the first to fifth groups in Table 2 are all less than 0, which indicates that the color of Yogurt ice cream in each group is biased toward green. In addition, the a * value of the second to fifth groups is smaller than the a * value of the first group, which shows that the color of the yogurt ice cream with added mangosteen fruit pulp is more greenish.

In terms of b * values, the b * values of each group in Table 2 are greater than 0, indicating that the color of Yogurt ice cream in each group is biased toward yellow. Moreover, it can be found that with the increase of the content of Soursop fruit, the b * value of Yogurt ice cream also rises, indicating that the color of Yogurt ice cream gradually becomes dark yellow. As the carotenoids of Soursop fruit have about 0.004 micrograms / 100 grams, the change of b * value is affected.

Table 3 shows the analysis results of the viscosity, melting rate, expansion rate, hardness, and cohesion of Yogurt ice cream in each group.

table 3 Group Viscosity (cp) Melting rate (g / min) Expansion rate (%) Hardness (g) Cohesion First group 226 1.15 67.53 101.37 0.01542 Second Group 343 1.06 62.23 187.19 0.0591 The third group 523 0.97 59.33 239.81 0.06007 Fourth group 1053 0.94 51.83 352.74 0.15019 Fifth group 1422 0.86 48.40 552.6 0.16465

As can be seen from Table 3, the viscosity of the yogurt ice cream increased with the increase in the content of Soursop. Due to the large amount of polysaccharides contained in the fruit pulp of Soursop, it can play the role of a thickener in food, thus causing the viscosity of Yogurt ice cream to increase.

The melting rate of ice cream indicates its resistance to temperature. In Table 3, the yoghurt ice cream (ie, the first group) without the mangosteen fruit pulp has the highest melting rate, and the yoghurt ice cream (ie, the fifth group) with 20% by weight of the mangosteen fruit The melting rate is low. With the increase of the content of Soursop fruit, the melting rate also gradually increased. Because the fruit of Soursop Syrup in Yogurt Ice Cream contains a large amount of polysaccharides, and the polysaccharides can absorb water, thereby reducing the melting rate of Yogurt Ice Cream.

During the process of making yogurt, the air will enter the homogenate and / or the ice cream mixture, so that the volume of the yogurt produced is greater than the total volume of all ingredients. The percentage increase in volume is the expansion of the ice cream. Expansion rate is an important indicator to measure the quality of ice cream products. When the expansion rate is too high, Yogurt ice cream will appear frosty, loose, and taste bad. It can be seen from Table 3 that the swelling rate of Yogurt ice cream decreases with the increase in the content of Soursop. Because the fruit of Soursop can play a role in increasing the viscosity in yogurt, and when the viscosity of yogurt rises, the less air enters the yogurt, so that the expansion rate of yogurt is lower.

The texture analysis results of Yogurt ice cream include determination of hardness and cohesion. It can be known from Table 3 that the higher the content of Soursop fruit pulp in yogurt, the higher the hardness of yogurt. Cohesion indicates the ratio of the work done to overcome the attractive force between the probe and the probe during the first and second compressions of the yogurt ice cream after two compressions. It can be known from Table 3 that as the content of Soursop fruit pulp in Yogurt ice cream increases, the cohesiveness of Yogurt ice cream also increases significantly.

Figure 2 shows the results of analysis of gastric acid tolerance of lactic acid bacteria in each group of yogurt. Figure 3 shows the results of analysis of bile salt tolerance of lactic acid bacteria in each group of yogurt. Referring to FIG. 3, the figure shows that when the content of Soursop fruit pulp in yogurt ice cream is 10% by weight or more (that is, the second group to the fifth group), the number of lactic acid bacteria significantly increases. Referring to FIG. 3, when the content of Soursop fruit pulp in yogurt ice cream is 10% by weight or more, the number of lactic acid bacteria significantly increases.

Figures 4 and 5 respectively show the changes of the bacterial counts of lactic acid bacteria and Streptococcus thermophilus in Yogurt ice cream over a period of 60 days in each group of Yogurt ice cream. As can be seen from FIG. 4 and FIG. 5, the lactic acid bacteria and the Streptococcus thermophilus bacteria contained in each group of Yogurt ice cream were frozen from the 0th day (that is, the start date of being placed in the freezing environment) to the 60th day. The number remained approximately constant, indicating that probiotics such as lactic acid bacteria and Streptococcus thermophilus in yogurt yogurt containing pulp of Soursop litchi did not reduce their survival rate due to low temperature.

FIG. 6 and FIG. 7 respectively show the change of the bacterial counts of lactic acid bacteria and Streptococcus thermophilus in Yogurt ice cream on the starting day of each group of Yogurt ice cream in a freezing environment at -20 ° C. Referring to FIG. 6, the figure shows that when Yogurt ice cream contains 10% of Soursop fruit pulp (ie, the second group), the number of lactic acid bacteria is compared with that of Yogurt ice cream (ie, the first Group) have risen significantly. Moreover, with the increase of the content of Soursop fruit, the number of lactic acid bacteria also increased. Referring to FIG. 7, it is shown that when Yogurt ice cream contains 10% of Soursop fruit (that is, the second group), the number of Streptococcus thermophilus bacteria increases significantly compared to the first group. In addition, with the increase in the content of Soursop, the number of S. thermophilus bacteria increased. Due to the large amount of polysaccharides in the fruit pulp of Soursop, the viscosity of yogurt is increased. In a frozen environment, the higher viscosity Yogurt ice cream can form fewer ice crystals, thereby reducing the cell damage of probiotics and the adverse effect on cell survival.

2,2-Diphenyl-1-bitterate (DPPH) is a stable free radical with strong light absorption at 517 nm. When interacting with a substance with anti-oxidation ability, DPPH radicals accept electrons to form an electron pair, which causes its absorbance at 517 nm to decrease or disappear. The lower the measured absorbance of DPPH, the stronger the antioxidant capacity of the substance. In other words, the higher the rate of change in absorbance of a substance before and after its action with DPPH free radicals, the better its ability to scavenge DPPH free radicals, that is, the stronger its antioxidant capacity. FIG. 8 shows the DPPH radical interaction between each group of Yogurt ice cream and the change in the absorbance of DPPH radical calculated by the above formula 3. It can be seen from FIG. 8 that the yogurt ice cream of the first group has the lowest DPPH free radical scavenging ability, and the fifth group has the highest scavenging ability. It can be known that when the content of Soursop fruit pulp in Yogurt ice cream gradually increases, the antioxidant capacity of Yogurt ice cream also shows a significant improvement.

Polyphenolic compounds (Polyphenolic compounds) on the benzene ring with a reducing end of the hydroxyl group will react with Flynn reagent to color, and has a maximum absorbance at 750 nm. A higher light absorption value indicates a higher total polyphenol content. The Yogurt ice cream was reacted with Fulin reagent and the absorbance value of each group was measured, and the equivalent of gallic acid was used as a reference. The total polyphenol content of the Yogurt ice cream was calculated by using the measured absorbance value. Figure 9 shows the total polyphenol content obtained from the interaction between Yogurt ice cream and Fulin reagent in each group. It can be seen from FIG. 9 that the total polyphenol content of the yogurt in the first group is the lowest, and the highest in the fifth group. It can be seen that when the content of Soursop fruit pulp in Yogurt ice cream gradually increases, the total polyphenol content of Yogurt ice cream also increases, thereby significantly improving the antioxidant capacity.

Figure 10 shows the results of sensory evaluation of each group of Yogurt ice cream. The items include appearance, aroma, flavor, texture, and overall acceptance. In terms of appearance, there was no significant difference between the groups of Yogurt ice cream. In terms of aroma, the third group scored the highest. In terms of flavor, the second group scored the highest, and the third group ranked second. Here, the yoghurt ice cream (ie, the second group and the third group) containing 5 to 10% by weight of Soursop fruit pulp has better aroma and flavor. In terms of texture, the fifth group scored the highest, and as the content of Soursop Litchi pulp decreased, the texture evaluation score also decreased. Here, it can be seen that when Yogurt ice cream contains Soursop fruit pulp, it helps to improve the texture of Yogurt Ice Cream, and the higher the content, the better the texture. In terms of overall acceptance, the second group scored highest, and the third group followed. Here, it can be seen that Yogurt ice cream containing 5 to 10% by weight of Soursop fruit pulp can obtain a high degree of acceptance.

In summary, the yogurt ice cream and the method for manufacturing the yogurt ice cream according to the embodiments of the present invention are suitable for making an ice cream product, so that the prepared yogurt ice cream can exhibit good appearance, aroma, flavor and texture. In addition, by adding Soursop fruit pulp to Yogurt ice cream and adjusting the appropriate formula, not only can the probiotics in Yogurt ice cream be reduced in the environment of low temperature, low pH, high acidity, high bile salt, It can also improve the antioxidant capacity of yogurt. That is to say, the polysaccharides from the fruit pulp of Soursop can not only prevent the probiotics in Yogurt ice cream from reducing the survival rate in the freezing environment, but also promote the growth of probiotics and increase the number of lactic acid bacteria. It can also make probiotics high in the human digestive system. The physiological effects of gastric acid and high choline are maintained, thereby improving the nutritional properties of yogurt. In addition, the fruit of Soursop can provide higher viscosity of Yogurt ice cream, reduce the melting rate of the ice cream itself, and make Yogurt ice cream excellent in shape retention, texture and texture. Therefore, the Soursop fruit pulp in the ice cream of the embodiment of the present invention can provide the effect equivalent to various commercially available emulsifiers or stabilizers, and the ice cream of the embodiment of the present invention can maintain more excellent nutritional value.

S11 Mix eggs and sweeteners into a first mixture S12 Add milk and cream to the first mixture to mix into a second mixture S13 Heat the second mixture S14 Stir the heated second mixture with a conditioning rod for 3 minutes to form a homogeneous mixture S15: The homogenate is matured at 4 ° C for 16 hours. S16: Soursop fruit pulp and yogurt are added to the homogenate after ripening to form an ice cream mixture. S17 is defrosted with a blender until the ice cream mixture is thick and creamy.

FIG. 1 is a flow block diagram of a method for manufacturing a yogurt ice cream according to an embodiment of the present invention. FIG. 2 is a graph showing analysis results of gastric acid tolerance of lactic acid bacteria in Yogurt ice cream according to an embodiment of the present invention. FIG. 3 is a graph showing analysis results of bile salt tolerance of lactic acid bacteria in Yogurt ice cream according to an embodiment of the present invention. FIG. 4 is a graph showing a change curve of the number of lactic acid bacteria in the yogurt ice cream according to the embodiment of the present invention with respect to the number of days of storage in an environment of -20 ° C. FIG. 5 is a graph showing a change curve of the number of Streptococcus thermophilus relative to the number of days of storage in an environment of -20 ° C. according to an embodiment of the present invention. FIG. 6 is a graph of analysis results of changes in the number of lactic acid bacteria in Yogurt ice cream relative to the content of Soursop fruit in the example of the present invention. FIG. 7 is a graph of analysis results of changes in the number of Streptococcus thermophilus relative to the content of Soursop fruit in Yogurt ice cream according to an example of the present invention. FIG. 8 is a graph showing analysis results of changes in DPPH radical scavenging rate of Yogurt ice cream with respect to the content of Soursop fruit in the Example of the present invention. FIG. 9 is a graph showing the analysis result of the change of the total polyphenol content of the Yogurt ice cream with respect to the content of the fruit of Soursop. FIG. 10 is a diagram of analysis results of sensory evaluation of yogurt ice cream according to an embodiment of the present invention.

Claims (5)

A Yogurt ice cream, comprising: 10% to 25% by weight of milk; 5% to 20% by weight of Annona muricata pulp; 27% by weight of Yogurt, wherein the Yogurt contains 9.59 to 9.67 Log CFU / ml of Lactobacillus bulgaricus and 9.70 ~ 9.82 log CFU / ml of Streptococcus thermophilus; 12% by weight of sweeteners; 13% by weight of eggs; and 18% by weight of cream. The yogurt ice cream according to claim 1, wherein the content of the Soursop is 5 to 10% by weight. The yogurt ice cream according to claim 2, wherein the content of the Soursop is 5 wt%. A method for making yogurt ice cream, comprising: mixing eggs and sweeteners into a first mixture; adding milk and cream to the first mixture to mix into a second mixture; heating the second mixture; stirring with a conditioning rod The second mixture is heated for 3 minutes to form a homogeneous substance; the homogeneous substance is matured at 4 ° C for 16 hours; the succulent fruit and yogurt are added to the matured homogeneous substance to form an ice cream mixture, wherein The ice cream mix has 10-25% by weight of the milk, 5-20% by weight of the Soursop fruit pulp, 27% by weight of the Yogurt, 12% by weight of the sweetener, and 13% by weight of the egg yolk. And 18% by weight of the cream, wherein the yogurt contains 9.59 to 9.67 log CFU / ml of Lactobacillus bulgaricus and 9.70 to 9.82 log CFU / ml of Streptococcus thermophilus; The material was thick and creamy. The method for manufacturing a yogurt ice cream according to claim 4, further comprising: hardening the frozen ice cream mixture at a temperature of less than or equal to -20 ° C.