Coenzyme q10 nanoemulsion yogurt and preparation method thereof

Abstract

This invention discloses a CoQ10 nanoemulsion yogurt and its preparation method, belonging to the field of food processing technology. The preparation method of the CoQ10 nanoemulsion yogurt of this invention includes the following steps: mixing whey protein with water, hydrating, and thermally polymerizing to obtain a polymerized whey protein solution; mixing the polymerized whey protein solution with a CoQ10 solution, emulsifying, and evaporating to remove the solvent from the CoQ10 solution to obtain a PWP-CoQ10 nanoemulsion; mixing the PWP-CoQ10 nanoemulsion with milk to obtain a precursor liquid, emulsifying, heating, and then adding a starter culture for fermentation to obtain the CoQ10 nanoemulsion yogurt. The CoQ10 nanoemulsion yogurt prepared by this invention possesses both the antioxidant properties of CoQ10 and the thickener function of whey protein; compared with ordinary yogurt, it has the characteristics of high protein content, good antioxidant effect, and no additional thickener added, expanding the application of CoQ10 in the food field and showing good prospects for promotion and application in the field of functional yogurt.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, and in particular to a coenzyme Q10 nanoemulsion yogurt and its preparation method. Background Technology

[0002] Coenzyme Q10 (CoQ10), also known as ubiquinone, is a hydrophobic polyene quinone compound. CoQ10 is a naturally occurring compound in the human body and plays an important role in cellular energy production. CoQ10 possesses excellent antioxidant activity, inhibiting cell membrane lipid oxidation, scavenging free radicals, inhibiting reactive oxygen species, preventing mitochondrial DNA mutations, and reducing cellular oxidative stress levels, thereby inhibiting apoptosis. CoQ10 also has functions such as relieving fatigue, improving immunity, and delaying aging, making it a potential product for health food development. Furthermore, CoQ10 also has beautifying effects, including protecting the skin from UV damage, promoting collagen production, and inhibiting melanin production. The synthesis of CoQ10 in the human body gradually decreases with age. When its level falls below 25%, it cannot meet the body's needs, requiring supplementation to maintain health. Studies have confirmed a strong correlation between CoQ10 deficiency and the occurrence and development of many chronic diseases, such as hypertension, cardiovascular disease, and neurodegenerative diseases. Moreover, some studies have shown that CoQ10 can be used as an adjunct treatment for myocarditis following COVID-19 infection. However, CoQ10 has poor water solubility, is easily decomposed by light, and has low bioavailability when taken orally, which severely limits its application in functional health foods.

[0003] Whey protein is one of the main components of milk protein. As a high-quality protein, it is rich in various essential amino acids, has high bioavailability, and possesses excellent emulsifying, film-forming, and gelling properties. Currently, whey protein is also commonly added to yogurt as an ingredient to increase viscosity and improve yogurt quality. In addition to the uses mentioned above, as a delivery carrier, whey protein can resist hydrolysis by pepsin, protecting functional factors and ensuring their smooth passage through the gastric environment for intestinal absorption. Delivery systems based on whey protein have been widely used for the encapsulation and delivery of functional factors in food, effectively improving their physicochemical properties, stability, and bioavailability.

[0004] As living standards improve, people are demanding higher quality of life and placing greater emphasis on functional properties of food beyond nutritional value, such as antioxidant properties. Yogurt, with its high nutritional value and health benefits, is a popular product with a significant market share. Developing new functional health yogurts is a crucial branch of research and development for dairy companies. Therefore, designing a functional yogurt rich in CoQ10 is particularly important for expanding the application of CoQ10 in functional health foods. Summary of the Invention

[0005] The purpose of this invention is to provide a CoQ10 nanoemulsion yogurt and its preparation method. The CoQ10 nanoemulsion yogurt prepared by this invention possesses both the antioxidant properties of CoQ10 and the thickener function of whey protein. Compared with ordinary yogurt, it features high protein content, excellent antioxidant effects, and no added thickeners, thus expanding the application of CoQ10 in the food industry and showing promising prospects for promotion and application in the functional yogurt field.

[0006] To achieve the above objectives, the present invention provides the following technical solution: One of the technical solutions of this invention is to provide a method for preparing CoQ10 nanoemulsion yogurt, comprising the following steps: (1) Mix whey protein with water, hydrate, and thermally polymerize to obtain a polymerized whey protein solution; (2) The polymerized whey protein solution is mixed with the CoQ10 solution, emulsified, and the solvent of the CoQ10 solution is removed by evaporation to obtain PWP-CoQ10 nanoemulsion; (3) The PWP-CoQ10 nanoemulsion is mixed with milk to obtain a precursor liquid, emulsified, heated, and then a starter culture is added for fermentation to obtain the CoQ10 nanoemulsion yogurt.

[0007] Preferably, in step (1): the whey protein has a protein content of 94 wt%, and the mass ratio of whey protein to water is 1:10; the hydration temperature is 4℃ and the time is 8-16 h; the stirring speed of the thermal polymerization is 80-150 rpm, the temperature is 70-90℃, and the time is 10-30 min.

[0008] Stirring must be maintained during the thermal polymerization process, otherwise it will affect the polymerization effect of whey protein.

[0009] Preferably, the process further includes adjusting the pH to 7.0 before the thermal polymerization operation.

[0010] The pH adjustment is achieved by adding NaOH solution. The concentration of NaOH solution should not be too low (>0.5 mol / L), otherwise the volume of whey protein solution will increase significantly, resulting in a decrease in whey protein concentration and affecting the subsequent preparation of nanoemulsion.

[0011] Preferably, in step (2): the CoQ10 solution is a CoQ10 ethyl acetate solution with a concentration of 10 mg / mL; the mass ratio of whey protein to CoQ10 is 16-20:1; the emulsification is performed at a speed of 10000-12000 rpm for 1-5 min, and then homogenized twice using a microfluidic homogenizer at 50 MPa.

[0012] Preferably, in step (3): the concentration of CoQ10 in the precursor solution is 0.04-0.22 mg / mL; the emulsification is carried out at 10000-12000 rpm for 1-5 min; the heating temperature is 80-90℃ and the heating time is 15 min.

[0013] Single-factor experiments showed that yogurt with 0.13 mg / mL CoQ10 nanoemulsion had the best taste and stronger antioxidant capacity. Based on the optimal daily intake of 30 mg-50 mg, the recommended daily consumption of this beverage (calculated per 100 mL) is 3 cups.

[0014] Preferably, in step (3): the fermentation agent is ABY-8 fermentation agent, and the ratio of the amount added to the precursor liquid is 0.3 mg / mL; the fermentation temperature is 40-45℃, and the time is 4.5-5.5 h.

[0015] Although the fermentation process in step (3) may theoretically affect the stability of CoQ10, the antioxidant value of CoQ10 in the finished yogurt product shows that the fermentation process has little impact on its encapsulation effect.

[0016] The invention adds PWP-CoQ10 nanoemulsion before sterilization to avoid fermentation failure due to contamination by other microorganisms, thus making the product properties more stable.

[0017] The second technical solution of the present invention is to provide a CoQ10 nanoemulsion yogurt prepared according to the above preparation method.

[0018] The beneficial technical effects of the present invention are as follows: This invention solves the problem of CoQ10's poor water solubility, which hinders its application in food. CoQ10 is encapsulated in polymeric whey protein (PWP) to prepare a nanoemulsion, making it water-soluble with an encapsulation rate of up to 95%, without introducing any additional ingredients / additives. This method improves the intestinal absorption and bioavailability of CoQ10. Specifically, after in vitro gastrointestinal digestion, the bioavailability of CoQ10 in yogurt is approximately 7 times that of free CoQ10 (75.37±0.84 vs 10.75±1.70). Adding CoQ10 nanoemulsion enhances the antioxidant activity of yogurt, while the basic physicochemical properties, textural characteristics, and sensory quality of the yogurt remain largely unchanged.

[0019] The whey protein used as the encapsulating wall material is one of the main components of milk protein and a common food ingredient in fermented yogurt. This invention provides a method for producing CoQ10 nanoemulsion yogurt by encapsulating CoQ10 in whey protein to form a nanoemulsion. The resulting yogurt has good stability, high protein content, high antioxidant capacity, and a pleasant taste, and has high nutritional value.

[0020] The CoQ10 nanoemulsion yogurt prepared by this invention possesses both the antioxidant properties of CoQ10 and the thickener function of whey protein. Compared with ordinary yogurt, it has the characteristics of high protein content, good antioxidant effect, and no additional thickener added, which expands the application of CoQ10 in the food field and has good prospects for promotion and application in the field of functional yogurt. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 The images shown are physical pictures of the products obtained in Example 3 and Comparative Examples 1-2. In the images, A represents Comparative Example 1; B represents Example 3; and C represents Comparative Example 2.

[0023] Figure 2 This is a comparison of the antioxidant activities of the products obtained in Example 3 and Comparative Examples 1-2. Wherein, (a) is the ABTS free radical scavenging rate, and (b) is the total reducing power. Detailed Implementation

[0024] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0025] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0026] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0027] The terms “comprising,” “including,” “having,” “containing,” etc., used in this invention are all open-ended terms, meaning that they include but are not limited to.

[0028] More preferably, in the following embodiments of the present invention, the thermal polymerization is carried out under a magnetic stirrer; after the thermal polymerization is completed, the process further includes a step of cooling to 25°C in an ice bath.

[0029] More preferably, in the following embodiments of the present invention, aluminum foil is used to shield the light throughout the operation to prevent CoQ10 decomposition.

[0030] More preferably, in the following embodiments of the present invention, the preparation of the precursor liquid further includes a step of adding a sweetener; the sweetener is one or more of the following: granulated sugar, acesulfame potassium, aspartame, sucralose, erythritol, maltitol, sorbitol, steviol glycosides, mogrosides, and isomaltooligosaccharides.

[0031] The whey protein used in the following embodiments and comparative examples of the present invention is whey protein isolation (WPI), with a protein content of 94 wt%.

[0032] The CoQ10 used in the following embodiments and comparative examples of this invention has a purity greater than 99% and was purchased from Xiamen Kingway Group Co., Ltd.

[0033] All raw materials used in the following embodiments and comparative examples of the present invention are commercially available products.

[0034] Example 1 Preparation of CoQ10 nanoemulsion yogurt: (1) Weigh 10 g of whey protein and dissolve it in 100 mL of deionized water (100 mg / mL). Use a magnetic stirrer to dissolve it at 200 rpm and place it in a refrigerator at 4℃ for 12 h to hydrate the protein. Adjust the pH of the solution to 7.0 with NaOH solution (1 mol / L), and then heat it at 125 rpm and 85℃ for 30 min using a magnetic stirrer. Then, lower the temperature to 25℃ by using an ice bath to obtain a polymerized whey protein solution (PWP solution).

[0035] (2) Weigh 5g of CoQ10 and dissolve it in 500 mL of ethyl acetate (10 mg / mL) to obtain a CoQ10 solution; mix 100 mL of PWP solution with 50 mL of CoQ10 solution (2:1, v / v) and homogenize it for 2 min at 12000 rpm using a high-speed disperser, then homogenize it twice at 50 MPa using a microfluidic homogenizer, and finally remove the ethyl acetate from the nano-dispersion using a vacuum rotary evaporator at 35 °C, and add deionized water to ensure that the sample volume is 100 mL to obtain PWP-CoQ10 nanoemulsion; use aluminum foil to shield from light throughout the production process to prevent CoQ10 decomposition.

[0036] (3) Using 100 mL of pure milk as the base, add 7 g of white sugar and 0.8 mL of PWP-CoQ10 nanoemulsion. Homogenize at 12000 rpm for 5 min using a high-speed disperser. Then sterilize in a magnetic stirring water bath at 120 rpm and 85℃ for 15 min. Quickly cool to 42℃ in an ice water bath. Inoculate 30 mg of ABY-8 starter culture in a clean bench and mix well. Ferment in a 42℃ constant temperature fermentation chamber for 5 h. After cooling to room temperature, place in a 4℃ refrigerator for 12 h of post-ripening to obtain CoQ10 nanoemulsion yogurt (CoQ10 concentration is 0.04 mg / mL).

[0037] Example 2 The only difference from Example 1 is that the amount of PWP-CoQ10 nanoemulsion added in step (3) is changed to 1.8 mL.

[0038] Example 3 The only difference from Example 1 is that the amount of PWP-CoQ10 nanoemulsion added in step (3) is changed to 2.6 mL.

[0039] Comparative Example 1 (Commercially Available Yogurt) The only difference from Example 3 is that the addition of PWP-CoQ10 nanoemulsion in step (3) is omitted.

[0040] Comparative Example 2 (uncovered) Preparation of free CoQ10 yogurt: (1) Weigh 0.5g of CoQ10 and dissolve it in 50 mL of ethyl acetate (10 mg / mL) to obtain a CoQ10 solution. Homogenize the solution using a high-speed disperser at 12000 rpm for 2 min. Then homogenize it twice using a microfluidic homogenizer at 50 MPa. Finally, remove the ethyl acetate from the nano-dispersion using a rotary evaporator at 35℃. Add deionized water to ensure that the sample volume is 100 mL to obtain a CoQ10 solution. Use aluminum foil to protect the light during the entire production process to prevent the decomposition of CoQ10.

[0041] (2) Using 100 mL of pure milk as the base, add 7 g of white sugar and 2.6 mL of CoQ10 solution. Homogenize at 12000 rpm for 5 min using a high-speed disperser. Then sterilize in a magnetic stirring water bath at 120 rpm and 85℃ for 15 min. Quickly cool to 42℃ in an ice water bath. Inoculate 30 mg of ABY-8 starter culture in a clean bench and mix well. Ferment in a 42℃ constant temperature fermentation box for 5 h. After cooling to room temperature, place in a 4℃ refrigerator for 12 h of post-ripening to obtain free CoQ10 yogurt.

[0042] Effect verification (1) Take photographs of the products of Example 3 and Comparative Examples 1-2, and observe the product appearance, such as... Figure 1 As shown.

[0043] Figure 1 The images shown are physical pictures of the products obtained in Example 3 and Comparative Examples 1-2. A) Yogurt without CoQ10 added is Comparative Example 1; B) Yogurt with CoQ10 nanoemulsion is Example 3; C) Yogurt with free CoQ10 is Comparative Example 2.

[0044] like Figure 1 As shown, the yogurt prepared in Comparative Example 1 follows a common formula for commercially available yogurt, exhibiting a homogeneous and stable system. The product obtained in Example 3 has a similar morphology to Comparative Example 1, and no CoQ10 precipitation due to disruption of the encapsulation structure was observed, indicating that the defined preparation method does not adversely affect the product's appearance. However, the product system in Comparative Example 2 is heterogeneous, exhibiting obvious stratification (the yellowish portion of the liquid surface in the figure), primarily due to CoQ10 precipitation and floating on the yogurt surface.

[0045] (2) Sensory Evaluation Analysis: Based on GB19302—2025 "National Food Safety Standard for Fermented Milk", 10 food quality and safety professionals from the College of Food Science and Technology of Northeast Agricultural University were selected to conduct a sensory evaluation of the product to comprehensively analyze its public acceptance and liking. Specifically, the main characteristics of the product were determined from its color, aroma, taste, texture, and overall evaluation. Analysis of variance and data processing were performed using SPSS software. The scoring criteria are shown in Table 1.

[0046] Table 1 The test results are shown in Table 2.

[0047] Table 2 Table 2 shows that, within the range of CoQ10 addition amounts in each embodiment, the sensory scores gradually increased with increasing CoQ10 concentration, i.e., Example 3 > Example 2 > Example 1. Example 3 had a good score, while the free CoQ10 yogurt in Comparative Example 2 had the worst sensory evaluation score, mainly due to unacceptable color and taste to the subjects. This result indicates that in this whey protein delivery system, increasing the CoQ10 addition amount does not degrade sensory quality; on the contrary, it helps to improve taste, color, and texture.

[0048] (3) Antioxidant activity analysis: After obtaining the above products, the ABTS radical scavenging rate and total reducing power of the products of Example 3 and Comparative Examples 1-2 were immediately tested using a UV spectrophotometer. The test results are as follows: Figure 2As shown in Table 3. Table 3 contains the relevant data for storage for 0 days.

[0049] Table 3 Figure 2 This is a comparison of the antioxidant activities of the products obtained in Example 3 and Comparative Examples 1-2. Wherein, (a) is the ABTS free radical scavenging rate, and (b) is the total reducing power.

[0050] like Figure 2 As shown, with the extension of storage period and the deepening of fermentation, some of the encapsulated whey protein in the wall material is destroyed, and CoQ10 is deactivated after precipitation, resulting in a decrease in the antioxidant properties of yogurt. However, the ABTS free radical scavenging rate and total reducing power of Example 3 are higher than those of Comparative Example 1, indicating that the addition of CoQ10 nanoemulsion can improve the antioxidant activity of yogurt during storage and is relatively stable.

[0051] (4) Physicochemical performance analysis: The water-holding capacity was measured using a centrifuge, the pH value of the yogurt was measured using a pH meter, and the acidity was measured using an alkaline burette. The test results are shown in Table 4.

[0052] Table 4 (5) Texture analysis: The hardness, elasticity, cohesiveness, chewiness and adhesiveness of this product were analyzed using a texture analyzer. The test results are shown in Table 5.

[0053] Table 5 As shown in Table 5, the texture hardness of Example 3 is greater than that of Comparative Examples 1-2. This may be due to the higher protein content leading to a higher degree of cross-linking in the gel network, resulting in a denser and harder gel structure, thus exhibiting higher yogurt hardness. Example 3 is closest to Comparative Example 1 in terms of elasticity, chewiness, and adhesiveness. There is no significant difference in cohesion between Example 3 and Comparative Example 2, both being slightly lower than Comparative Example 1. Comparative Example 2 has the lowest chewiness and adhesiveness, meaning it has the worst texture.

[0054] The experimental conclusions drawn from the above specific implementation methods are as follows: CoQ10 nanoemulsion yogurt prepared by encapsulating CoQ10 with whey protein exhibits high antioxidant properties (Example 3 > Comparative Example 2 > Comparative Example 1). Furthermore, the physicochemical and textural properties of the CoQ10 nanoemulsion yogurt in Example 3 are not significantly different from those of Comparative Example 1 (ordinary yogurt without CoQ10). However, the addition of free CoQ10 in Comparative Example 2 significantly affects the physicochemical, textural, and sensory properties of the yogurt. The chewiness, adhesiveness, and various sensory scores of Comparative Example 2 are far lower than those of Example 3, indicating that the whey protein-based CoQ10 nanoemulsion effectively improves its water solubility and avoids changes in yogurt texture caused by CoQ10 exposure, thus preventing a decrease in sensory quality.

[0055] (6) Intestinal absorption test of CoQ10: The intestinal absorption of Example 3 and Comparative Example 2 was tested by simulating the gastrointestinal digestion process.

[0056] The test results showed that the bioavailability of CoQ10 in the yogurt after in vitro gastrointestinal digestion in Comparative Example 2 was 10.75±1.70, while that in Example 3 was 75.37±0.84, which is about 7 times that of Comparative Example 2.

[0057] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing CoQ10 nanoemulsion yogurt, characterized in that, Includes the following steps: (1) Mix whey protein with water, hydrate, and thermally polymerize to obtain a polymerized whey protein solution; (2) The polymerized whey protein solution is mixed with the CoQ10 solution, emulsified, and the solvent of the CoQ10 solution is removed by evaporation to obtain PWP-CoQ10 nanoemulsion; (3) The PWP-CoQ10 nanoemulsion is mixed with milk to obtain a precursor liquid, emulsified, heated, and then a starter culture is added for fermentation to obtain the CoQ10 nanoemulsion yogurt.

2. The preparation method according to claim 1, characterized in that, In step (1): the whey protein has a protein content of 94 wt% and the mass ratio of whey protein to water is 1:10; the hydration temperature is 4℃ and the time is 8-16 h; the stirring speed of the thermal polymerization is 80-150 rpm, the temperature is 70-90℃, and the time is 10-30 min.

3. The preparation method according to claim 1, characterized in that, Prior to the thermal polymerization operation, a step of adjusting the pH to 7.0 is also included.

4. The preparation method according to claim 1, characterized in that, In step (2): the CoQ10 solution is a CoQ10 ethyl acetate solution with a concentration of 10 mg / mL; the mass ratio of whey protein to CoQ10 is 16-20:1; the emulsification is carried out at a speed of 10000-12000 rpm for 1-5 min, and then homogenized twice at 50 MPa using a microfluidic homogenizer.

5. The preparation method according to claim 1, characterized in that, In step (3): the concentration of CoQ10 in the precursor solution is 0.04-0.22 mg / mL; the emulsification is carried out at 10000-12000 rpm for 1-5 min; the heating temperature is 80-90℃ and the heating time is 15 min.

6. The preparation method according to claim 1, characterized in that, In step (3): the fermentation agent is ABY-8 fermentation agent, and the ratio of the amount added to the precursor liquid is 0.3 mg / mL; the fermentation temperature is 40-45℃ and the time is 4.5-5.5 h.

7. A CoQ10 nanoemulsion yogurt prepared according to any one of claims 1-6.

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