EMULSION GEL EMBEDDING FAT-SOLUBLE VITAMIN AND PULSED ELECTRIC FIELD BASED PRODUCTION METHOD THEREFOR

Abstract

An emulsion gel embedding a fat-soluble vitamin and a pulsed electric field based production method therefor. The production method comprises: dissolving octenyl succinate starch ester in water, heating in a water bath, stirring to complete gelatinization and dissolution, and cooling to room temperature; adding edible oil dissolved with a fat-soluble vitamin to obtain a mixed liquid; shearing and homogenizing the obtained mixed liquid by using a high-speed shearing machine and a high-pressure homogenizer to obtain an emulsion; and adding the emulsion and natural starch to a methyl cellulose solution, performing pulsed electric field treatment after well mixing, heating in a water bath, performing degasification and cooling to obtain an emulsion gel. The pulsed electric field promotes interaction between methyl cellulose and starch molecules, has a higher elastic modulus, and is easier to form a network structure that is more conducive to embedding the fat-soluble vitamin.

Claims

1. A pulsed electric field based production method for an emulsion gel embedding a fat-soluble vitamin, characterized in that, the method comprises following preparation steps: (1) dissolving a starch octenyl succinate in water, heating in a water bath, stirring to complete gelatinization and dissolution, and cooling to room temperature; (2) adding an edible oil dissolved with a fat-soluble vitamin to a starch octenyl succinate solution in the step (1), preparing a crude emulsion by using a high-speed shearing machine, and then obtaining an emulsion via a high-pressure homogenizer; (3) adding a starch into the emulsion, and stirring evenly, to obtain a mixed solution; (4) adding a methylcellulose solution into the mixed solution prepared in the step (3), and performing a pulsed electric field treatment after stirring evenly, the pulsed electric field has an electric field strength of 5 to 15 kV/cm, and a frequency of 200 to 1000 Hz; and (5) heating a total mixture after the pulsed electric field treatment in a water bath at 80 to 95° C. for 15 to 30 min, degassing, and cooling, to obtain an emulsion gel.

2. The production method according to claim 1, characterized in that, in the step (1), a mass fraction of the starch octenyl succinate in terms of percent by weight is 5% to 15%.

3. The production method according to claim 1, characterized in that, the fat-soluble vitamin is any one or more of retinol, β-carotene, lycopene, lutein, tocopherol, sterols, and vitamin K.

4. The production method according to claim 1, characterized in that, the edible oil is any one or more of soybean oil, corn oil, peanut oil, rapeseed oil or olive oil.

5. The production method according to claim 1, characterized in that, in the step (2), an adding amount of the fat-soluble vitamin in terms of percent by weight is 0.02% to 0.1% of the mass of the crude emulsion; in the step (2), an adding amount of the edible oil is 5% to 25% of the volume of the crude emulsion.

6. The production method according to claim 1, characterized in that, in the step (3), the mass ratio of the starch to the emulsion is 10 to 20:100.

7. The production method according to claim 1, characterized in that, in the step (4), the methylcellulose solution is obtained by dissolving a methylcellulose in a phosphate buffer having a pH of 7.0, wherein, a concentration of the methylcellulose is 0.2% to 0.5%.

8. The production method according to claim 1, characterized in that, a weight ratio of the methylcellulose solution to the total mixture is 8% to 15%.

9. The production method according to claim 1, characterized in that, the pulsed electric field treatment has a pulsed width of 10 to 100 μs, a treatment time of 10 to 20 min, a waveform of a square wave, and a treatment temperature of 30 to 40° C.

10. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 1, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

11. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 2, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

12. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 3, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

13. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 4, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

14. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 5, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

15. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 6, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

16. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 7, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

17. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 8, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

18. An emulsion gel embedding a fat-soluble vitamin, characterized in that, it is produced by the production method according to claim 9, and the emulsion gel is a starch octenyl succinate-methylcellulose emulsion gel embedding the fat-soluble vitamin, which is used to replace a saturated fatty acid, and as a delivery system of a functional factor to embed the fat-soluble vitamin and a probiotic.

Description

DESCRIPTION OF DRAWINGS

[0033] FIG. 1 is an image for the finished product of the emulsion gel embedding lycopene in Example 1.

[0034] FIG. 2 is the effect of different strengths of the pulse electric field on the gelation time of the emulsion gels in the Examples of the present invention.

[0035] FIG. 3 is the rheological property curves of the emulsion gels embedding β-carotene in Example 2 and Comparative Example 1.

[0036] FIG. 4 is the effect of different strengths of the pulse electric field on the embedding rate of the emulsion gels in the Examples of the present invention.

[0037] FIG. 5 is the sustained release curves of β-carotene from the emulsion gels prepared in Comparative Example 1, Comparative Example 2 and Example 2 of the present invention in a simulated gastrointestinal fluid.

DETAILED DESCRIPTION OF EMBODIMENTS

[0038] For a better understanding of the present invention, the present invention is further described below in conjunction with the attached drawings and Examples, but the embodiments of the present invention are not limited thereto.

[0039] Determining method for the embedding rate of the fat-soluble vitamin:

[0040] The method includes the following steps: weighing accurately 2.0 g of an emulsion gel sample containing a fat-soluble vitamin, adding 20 mL of anhydrous ethanol, ultrasonically extracting for 5 min and then filtering for 3 times, and combining the filtrate. An absorbance value of the fat-soluble vitamin is measured by using an ultraviolet spectrophotometer at the specific absorption wavelength of the fat-soluble vitamin, and a content of the fat-soluble vitamin is calculated in combination with a standard curve of the fat-soluble vitamin. It is calculated according to the following formula:

Embedding rate=(the content of the fat-soluble vitamin in the emulsion gel/an initial adding amount of the fat-soluble vitamin)×100%

Example 1

[0041] Starch octenyl succinate was dissolved in water, placed in a boiled water bath and heated, stirred until it was completely gelatinized and dissolved, and cooled to room temperature. Lycopene-dissolved soybean oil was added to make the mixture contain 5% by mass of starch octenyl succinate, 0.1% by mass of lycopene and 10% by mass of soybean oil. A crude emulsion was prepared by using a high-speed disperser (IKA T25 high-speed disperser, Shanghai Shupei Experimental Equipment Co., Ltd.) with a shearing rotation speed of 15000 r/min and a shearing time of 2 min. Then, it was poured into a high-pressure homogenizer (M-110EH microfluidizer, American Microfluidics Company) and homogenized for 3 times under the condition of 80 Mpa, to obtain an emulsion. Then, a rice starch with a mass fraction of 8% was added, and mixed evenly, to obtain a mixed solution.

[0042] Methylcellulose was dissolved in a phosphate buffer (10 mM, pH 7.0), to prepare a methylcellulose solution with a mass concentration of 0.5%. After the prepared mixed solution and the methylcellulose solution were mixed uniformly at a ratio of 6:1 (w/w), the total mixture was treated for 20 min by means of a pulsed electric field (pulsed electric field SY-200, Guangzhou Xinan Food Technology Co., Ltd.), with a pulse frequency of 300 Hz, a pulse width of 100 μs, a pulse field strength of 5 kV/cm, and a treatment temperature of 30° C. Then, it was placed and heated in a hot water bath at 85° C. for 15 min, added into a cylindrical plastic test tube, degassed, sealed, and placed in an ice-water bath to cool down, to obtain an emulsion gel. FIG. 1 was the appearance of the lycopene-embedded emulsion gel prepared in Example 1. A gelation time of this emulsion gel was 1680 s, a maximum storage modulus in the test range of a frequency of 0.01 to 10 Hz was 1463 pa, and an embedding rate of lycopene by the emulsion gel reached 95.76%.

[0043] The forming time and the storage modulus of the emulsion gel were monitored by a rheometer, the emulsion gel samples were placed respectively between parallel plates, a gap between two plates was set to 3 mm, and a test temperature was 25° C. A storage modulus (G′) was determined as a function of time with a strain of 0.1%, a frequency of 1 Hz, and a testing time of 2 h. After the end of a time sweep, a frequency sweep was immediately performed with a frequency sweep range of 0.01 to 10 Hz and a strain of 0.1%. The gelation time was defined as the time corresponding to G′ greater than or equal to 1 Pa, and the result shows that the gelation time of this emulsion gel was 1680 s, which was shorter than that of the emulsion gel without a pulsed electric field treatment, which was 1900 s, and the data are shown in FIG. 2. FIG. 2 showed the effects of different strengths of pulsed electric field on the gelation time of starch octenyl succinate-methylcellulose emulsion gel under the above-mentioned conditions. It was illustrated that a pretreatment with the pulsed electric field could break an original hydrogen-bond network within and between methylcellulose molecules, and could promote the exposure of active groups in more starch molecules, so that the viscosity of the system increased and the formation of the gel network structure accelerated.

[0044] According to the test, the embedding rate of lycopene by this emulsion gel reached 95.76%, and the data was shown in FIG. 4. FIG. 4 showed the effects of the starch octenyl succinate-methylcellulose emulsion gel on the embedding rate of lycopene at different strengths of the pulsed electric field under the above-mentioned conditions. A high embedding rate made it difficult for a fat-soluble vitamin to undergo oxidation reactions with free radicals and metal ions in the water phase, which improved the storage stability of the fat-soluble vitamin; during a digestion process, dissolution and absorption of the fat-soluble vitamin in micelles was promoted, and a bioavailability of the fat-soluble vitamin increased.

Example 2

[0045] Starch octenyl succinate was dissolved in water, placed in a boiled water bath and heated, stirred until it was completely gelatinized and dissolved, and cooled to room temperature. Corn oil with suitable amount of β-carotene dissolved was added to make the mixture contain 5% by mass of starch octenyl succinate, 0.02% by mass of β-carotene and 10% by mass of corn oil. A crude emulsion was prepared by using a high-speed disperser (IKA T25 high-speed disperser, Shanghai Shupei Experimental Equipment Co., Ltd.) with a shearing rotation speed of 15000 r/min and a shearing time of 2 min. Then, it was poured into a high-pressure homogenizer (M-110EH microfluidizer, American Microfluidics Company) and homogenized for 3 times under the condition of 80 Mpa, to obtain an emulsion. Then, a corn starch with a mass fraction of 10% was added, and mixed evenly, to obtain a mixed solution.

[0046] Methylcellulose was dissolved in a phosphate buffer (10 mM, pH 7.0), to prepare a methylcellulose solution with a mass concentration of 0.5%. After the prepared mixed solution and the methylcellulose solution were mixed uniformly at a ratio of 8:1 (w/w), the total mixture was treated for 15 min with a pulsed electric field (pulsed electric field SY-200, Guangzhou Xinan Food Technology Co., Ltd.) with a pulse frequency of 600 Hz, a pulse width of 40 μs, a pulse field strength of 9 kV/cm, and a treatment temperature of 35° C. Then, it was placed in a hot water bath at 85° C. and heated for 15 min, added into a cylindrical plastic test tube, degassed, sealed, placed in an ice-water bath to cool down, and solidified to obtain an emulsion gel. A gelation time of this emulsion gel was 1500 s, a maximum storage modulus in the test range of a frequency of 0.01 to 10 Hz was 1472 pa, and an embedding rate of β-carotene by the emulsion gel reached 96.39%.

[0047] FIG. 3 is the rheological property curves of the emulsion gels in Example 2 and Comparative Example 1 which has not been treated with a pulsed electric field. An increase in the storage modulus G′ during the emulsion gelation process was considered to be an indication of an increase in the strength or hardness of the emulsion gel. As shown in FIG. 3, a maximum storage modulus in the test range of a frequency of 0.01 to 10 Hz of this emulsion gel was 1472 Pa, which was higher than the maximum storage modulus of 1200 Pa of the emulsion gel that have not been treated with a pulsed electric field, indicating that the pulsed electric field pretreatment can improve the storage modulus of the emulsion gel, and enhance the elastic strength of the emulsion gel.

Example 3

[0048] Starch octenyl succinate was dissolved in water, placed in a boiled water bath and heated, stirred until it was completely gelatinized and dissolved, and cooled to room temperature. Peanut oil with suitable amount of tocopherol dissolved was added to make the mixture contain 10% by mass of starch octenyl succinate, 0.08% by mass of tocopherol and 20% by mass of peanut oil. A crude emulsion was prepared by using a high-speed disperser (IKA T25 high-speed disperser, Shanghai Shupei Experimental Equipment Co., Ltd.) with a shearing rotation speed of 15000 r/min and a shearing time of 2 min. Then, it was poured into a high-pressure homogenizer (M-110EH microfluidizer, American Microfluidics Company) and homogenized for 3 times under the condition of 80 Mpa, to obtain an emulsion. Then, a potato starch with a mass fraction of 12% was added, and mixed evenly, to obtain a mixed solution.

[0049] Methylcellulose was dissolved in a phosphate buffer (10 mM, pH 7.0), to prepare a methylcellulose solution with a mass concentration of 3%. After the prepared mixed solution and the methylcellulose solution were mixed uniformly at a ratio of 12:1 (w/w), the total mixture was treated for 12 min with a pulsed electric field (pulsed electric field SY-200, Guangzhou Xinan Food Technology Co., Ltd.) with a pulse frequency of 1000 Hz, a pulse width of 10 μs, a pulse field strength of 12 kV/cm, and a treatment temperature of 30° C. Then, it was placed in a hot water bath at 85° C. and heated for 15 min, added into a cylindrical plastic test tube, degassed, sealed, placed in an ice-water bath to cool down, and solidified to obtain an emulsion gel. A gelation time of this emulsion gel was 1550 s, a maximum storage modulus of this emulsion gel in the test range of a frequency of 0.01 to 10 Hz was 1415 pa, and an embedding rate of tocopherol by the emulsion gel reached 93.54%.

Example 4

[0050] Starch octenyl succinate was dissolved in water, placed in a boiled water bath and heated, stirred until it was completely gelatinized and dissolved, and cooled to room temperature. Rapeseed oil with suitable amount of lutein dissolved was added to make the mixture contain 15% by mass of starch octenyl succinate, 0.06% by mass of lutein and 15% by mass of rapeseed oil. A crude emulsion was prepared by using a high-speed disperser (IKA T25 high-speed disperser, Shanghai Shupei Experimental Equipment Co., Ltd.) with a shearing rotation speed of 15000 r/min and a shearing time of 2 min. Then, it was poured into a high-pressure homogenizer (M-110EH microfluidizer, American Microfluidics Company) and homogenized for 3 times under the condition of 80 Mpa, to obtain an emulsion. Then, a cassava starch with a mass fraction of 18% was added, and mixed evenly, to obtain a mixed solution.

[0051] Methylcellulose was dissolved in a phosphate buffer (10 mM, pH 7.0), to prepare a methylcellulose solution with a mass concentration of 5%. After the prepared mixed solution and the methylcellulose solution were mixed uniformly at a ratio of 12:1 (w/w), the total mixture was treated for 10 min with a pulsed electric field (pulsed electric field SY-200, Guangzhou Xinan Food Technology Co., Ltd.) with a pulse frequency of 200 Hz, a pulse width of 80 μs, a pulse field strength of 15 kV/cm, and a treatment temperature of 40° C. Then, the above-mentioned mixture was placed in a hot water bath at 85° C. and heated for 15 min, added into a cylindrical plastic test tube, degassed, sealed, placed in an ice-water bath to cool down, and solidified to obtain an emulsion gel. A gelation time of this emulsion gel was 1570 s, a maximum storage modulus of this emulsion gel in the test range of a frequency of 0.01 to 10 Hz was 1550 pa, and an embedding rate of lutein by the emulsion gel reached 92.28%.

Comparative Example 1

[0052] A preparation method for an emulsion gel, comprised the following steps:

[0053] Starch octenyl succinate was dissolved in water, placed in a boiled water bath and heated, stirred until it was completely gelatinized and dissolved, and cooled to room temperature. Corn oil with suitable amount of β-carotene dissolved was added to make the mixture contain 5% by mass of starch octenyl succinate, 0.02% by mass of β-carotene and 10% by mass of corn oil. A crude emulsion was prepared by using a high-speed disperser (IKA T25 high-speed disperser, Shanghai Shupei Experimental Equipment Co., Ltd.) with a shearing rotation speed of 15000 r/min and a shearing time of 2 min. Then, it was poured into a high-pressure homogenizer (M-110EH microfluidizer, American Microfluidics Company) and homogenized for 3 times under the condition of 80 Mpa, to obtain an emulsion. Then, a corn starch with a mass fraction of 10% was added, and mixed evenly, to obtain a mixed solution.

[0054] Methylcellulose was dissolved in a phosphate buffer (10 mM, pH 7.0), to prepare a methylcellulose solution with a mass concentration of 0.5%. After the prepared mixed solution and the methylcellulose solution were mixed uniformly at a ratio of 8:1 (w/w), it was placed in a hot water bath at 85° C. and heated for 15 min, added into a cylindrical plastic test tube, degassed, sealed, placed in an ice-water bath to cool down, and solidified to obtain an emulsion gel. A gelation time of this emulsion gel was 1910 s, a maximum storage modulus of this emulsion gel in the test range of a frequency of 0.01 to 10 Hz was 1200 pa, and an embedding rate of β-carotene by the emulsion gel reached 85.27%.

Comparative Example 2

[0055] Starch octenyl succinate was dissolved in water, placed in a boiled water bath and heated, stirred until it was completely gelatinized and dissolved, and cooled to room temperature. Corn oil with β-carotene dissolved was added to make the mixture contain 5% by mass of starch octenyl succinate, 0.02% by mass of β-carotene and 10% by mass of corn oil. A crude emulsion was prepared by using a high-speed disperser (IKA T25 high-speed disperser, Shanghai Shupei Experimental Equipment Co., Ltd.) with a shearing rotation speed of 15000 r/min and a shearing time of 2 min. Then, it was poured into a high-pressure homogenizer (M-110EH microfluidizer, American Microfluidics Company) and homogenized for 3 times under the condition of 80 Mpa, to obtain an emulsion. Then, a corn starch with a mass fraction of 10% was added, and mixed evenly. Then, it was placed in a hot water bath at 85° C. and heated for 15 min, added into a cylindrical plastic test tube, degassed, sealed, placed in an ice-water bath to cool down, and solidified to obtain an emulsion gel. A gelation time of this emulsion gel was 2014 s, a maximum storage modulus of this emulsion gel in the test range of a frequency of 0.01 to 10 Hz was 1183 pa, and an embedding rate of β-carotene by the emulsion gel reached 82.29%.

[0056] Implementation effect: The gelation times of Comparative Example 1 and Comparative Example 2 were longer than that of Example 2, and the elastic moduli of Comparative Example 1 and Comparative Example 2 were lower than that of Example 2, indicating that the pulse electric field pretreatment accelerated the formation of the gel network structure, and enhanced the elasticity of the gel. In Comparative Example 1, the embedding rate of β-carotene by the emulsion gel without pulsed electric field treatment reached 85.27%; and in Comparative Example 2, the emulsion gel was prepared by using starch octenyl succinate and natural starch as raw materials, and without adding methylcellulose, and its embedding rate of β-carotene was 82.29%, which were lower than the embedding rate, 95.76% of β-carotene by the emulsion gel subjected to the action of the pulsed electric field in Example 2. This indicates that the use of the pulsed electric field gelation pretreatment has a good embedding effect on the fat-soluble vitamin, and the compounding of methylcellulose and starch can synergize, and inhibit the flocculation of lipid droplets, and it is not easy for the fat-soluble vitamin to undergo oxidation reaction with free radicals and metal ions etc. in the water phase, which enhanced the storage stability of the fat-soluble vitamin and significantly improved the properties of the emulsion gel.

[0057] FIG. 5 is the sustained release curves of β-carotene in simulated gastrointestinal fluid. The effects of the emulsion gels obtained in Example 2, Comparative Example 1, and Comparative Example 2 on sustained release of β-carotene were studied. The experimental method was: dissolving 2 g of NaCl and 7 mL of HCl with a concentration of 37% in 1 L of water, adding 3.2 g of pepsin to prepare a gastric digestive juice, taking 1 g of the sample, mixing it with 10 mL of simulated gastric digestive juice, adjusting the pH to 2.5 at 37° C., performing a reaction at a speed of 100 r/min, respectively adding sodium phosphate to adjust the pH of the solution to 6.8 after 0, 30, 60, 90, 120, 150 min, weighing 6.8 g of KH.sub.2PO.sub.4, adding 600 mL of distilled water to dissolve it, then adjusting the pH to 6.8 with NaOH solution, adding 10 g of trypsin, dissolving, and diluting to 1000 mL with water. In this simulated intestinal fluid, the release degree of β-carotene was continued to be measured within 2.5 h, and samples were taken every 30 min. The absorbance was measured at 472 nm, and the release degree was calculated according to the standard curve of (3-carotene. The experimental results were shown in FIG. 5. It can be seen from FIG. 5 that the release rate of the emulsion gel treated with the pulsed electric field in the stomach was slower than those of the emulsion gels in Comparative Example 1 and Comparative Example 2 within 150 min. After reaching the intestinal tract, the release rate can reach more than 90%, realizing the sustained release of β-carotene.

[0058] In the present invention, the pulsed electric field can promote the interaction between methylcellulose and starch molecules. The system has a higher elastic modulus, and it is easier to form a network structure that is more conducive to embedding the fat-soluble vitamin. The network structure synergistically formed by methylcellulose and starch can effectively “embed” the fat-soluble vitamin, and reduce the speed of outward diffusion of the fat-soluble vitamin and other functional factors after dissolution, so as to achieve the purpose of slow release of the fat-soluble vitamin, and make it has certain sustained release and targeted delivery functions, improve its bioavailability within the body, and contain dietary fiber that is beneficial to health, which can meet needs of people for nutrition, health, and diversification of foods. It has potential application values in foods, health care products, biomedicines and other fields, and simultaneously has opened up a new way to research and develop new food base materials and improve the processing characteristics of foods, which leads to a good market prospect.

[0059] The embodiments of the present invention are not limited by the examples, and any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention should be equivalent replacement modes, and included in the protection scope of the present invention.