阅读说明：本技术 一种低油胶状乳液的制备方法 (Preparation method of low-oil colloidal emulsion ) 是由 徐献兵 毕安琪 宋亮 杜明 吴超 白长军 于 2019-09-26 设计创作，主要内容包括：本发明专利公开了一种低油胶状乳液的制备方法,包括以下步骤：S1、以南极磷虾为原料,经乙醇脱脂和碱溶酸沉提取南极磷虾蛋白粗提物；S2、将所述南极磷虾蛋白粗提物按浓度5～50mg/ml溶液于水,加热变性,待冷却后调节pH为4～5作为水相；S3、以食用植物油作为油相,将所述油相加到水相中,于超声功率密度4000W/cm<Sup>2</Sup>～12000w/cm<Sup>2</Sup>、作用5s～300s,形成胶状乳液。本发明制备的胶状乳液具有与高内相乳液类似的宏观形态,乳滴特征粒径大小为1～50μm,乳滴里面是有纳米级乳滴构成,且乳滴间通过丝状的蛋白桥连。本发明的胶状乳液制备方法,过程简单,无污染,操作方便,周期短,成本低,易于产业化。(The invention discloses a preparation method of low-oil colloidal emulsion, which comprises the following steps: s1, extracting a crude extract of euphausia superba protein by using euphausia superba as a raw material through ethanol degreasing and alkali-soluble acid precipitation; s2, adding the euphausia superba protein crude extract into water according to a solution with the concentration of 5-50 mg/ml, heating for denaturation, and cooling to adjust the pH to 4-5 to serve as a water phase; s3, taking edible vegetable oil as oil phase, adding the oil phase into water phase, and performing ultrasonic treatment at the power density of 4000W/cm 2 ～12000w/cm 2 And reacting for 5-300 s to form colloidal emulsion. The colloidal emulsion prepared by the method has a macroscopic form similar to that of a high internal phase emulsion, the characteristic particle size of emulsion droplets is 1-50 mu m, the emulsion droplets are formed by nanoscale emulsion droplets, and the emulsion droplets are bridged by filamentous protein. The preparation method of the colloidal emulsion has the advantages of simple process, no pollution, convenient operation, short period, low cost and easy industrialization.)

1. A method for preparing a low oil colloidal emulsion, comprising the steps of:

s1, preparing a crude euphausia superba protein extract: taking Antarctic krill meat, and beating into meat paste; degreasing the meat paste by using absolute ethyl alcohol to obtain degreased meat paste; removing ethanol in the defatted meat paste, and airing to obtain antarctic krill powder with the water content of less than 10% by weight; extracting protein in the antarctic krill powder by using an alkali-soluble acid precipitation method to obtain an antarctic krill protein crude extract;

s2, preparing a water phase: redissolving the crude euphausia superba protein extract obtained in the step S1 into a protein solution with the protein concentration of 5-50 mg/ml by using water; stirring the protein solution for 1-2 h at 80-100 ℃ to obtain a denatured protein solution; cooling the denatured protein solution to below 25 ℃, and adjusting the pH to 4-5 by using HCl to serve as a water phase; wherein the protein concentration of the protein solution is determined using the biuret method;

s3 preparation of emulsion: edible vegetable oil is used as an oil phase, the oil phase is added into the water phase obtained in the step S2, and the ultrasonic power density is 4000W/cm²～12000w/cm²Performing ultrasonic treatment for 5-300 s to obtain colloidal emulsion; wherein the volume ratio of the water phase to the oil phase is 1 (0.05-0.40).

2. The method for preparing the low-oil colloidal emulsion according to claim 1, wherein the step S1 of preparing the crude extract of Euphausia superba protein is specifically as follows: taking Antarctic krill meat, and beating the Antarctic krill meat at 10000-20000 rpm for 2-5 min to form meat paste; mixing the meat paste with absolute ethyl alcohol according to the weight ratio of 1 (7-10), and standing for 3-5 h at 25-30 ℃; removing ethanol in the meat paste, and airing the obtained meat paste until the weight percentage of the water content is below 10% to obtain antarctic krill powder; mixing the antarctic krill powder with 0.1-0.2N sodium hydroxide solution according to the weight ratio of 1 (9-11), stirring at 38-42 ℃ for 90-110 min at 100-200 rpm, centrifuging at 5500-10000 rpm for 20-30 min, and taking supernatant; and (3) regulating the pH value of the supernatant to 4-5 by using 1-2N hydrochloric acid, standing at 4 ℃ for 20-30 min, centrifuging at 5600-10000 rpm for 20-30 min, and taking a precipitate to obtain the euphausia superba protein crude extract.

3. The process for the preparation of a low oil emulsion according to claim 2, wherein said removal of ethanol from the emulsion is in particular: the minced meat is leached of ethanol using 8 layers of 100 mesh gauze.

4. The method for preparing a low-oil colloidal emulsion according to claim 1, wherein the stirring speed of step S2 is 100 to 200 rpm.

5. The method for preparing the low-oil colloidal emulsion of claim 1, wherein the protein solution is reconstituted at step S2 by: mixing the crude extract of the antarctic krill protein with deionized water, adjusting the pH to 8-8.5 by using NaOH solution, and stirring at 400-500 rpm for 6-12 h to obtain a protein solution with the protein concentration of 5-50 mg/ml.

6. The method of claim 1, wherein the edible vegetable oil of step S3 is soybean oil.

7. The method of preparing a low oil latex emulsion of claim 1, comprising the steps of:

s1, preparing a crude euphausia superba protein extract: taking Antarctic krill meat, and beating at 10000rpm for 5min to obtain meat paste; mixing the meat paste with absolute ethyl alcohol according to the weight ratio of 1:8, and standing for 4h at 26 ℃; then, leaching ethanol in the meat paste by using 8 layers of 100-mesh gauze, and placing the obtained meat paste in a fume hood for 12 hours to obtain antarctic krill powder with the water content of 10% by weight; mixing the antarctic krill powder with 0.1N sodium hydroxide solution according to the weight ratio of 1:10, stirring at 40 ℃ and 100rpm for 100min, and centrifuging at 5600rpm for 20 min; taking supernatant, adjusting pH to 4.5 with 1N hydrochloric acid, standing at 4 deg.C for 30min, and centrifuging at 5600rpm for 20 min; taking the precipitate to obtain a crude euphausia superba protein extract;

s2, preparing a water phase: mixing the crude euphausia superba protein extract obtained in the step S1 with deionized water, adjusting the pH to 8 by using NaOH solution, stirring at 450rpm for 8 hours, and redissolving into protein solution with the protein concentration of 50 mg/ml; stirring the protein solution at 100 ℃ and 100rpm for 1h to obtain a denatured protein solution; cooling the denatured protein solution to 25 ℃, and adjusting the pH of the denatured protein solution to 4.5 by using HCl to be used as an aqueous phase; wherein the protein concentration of the protein solution is determined by the biuret method;

s3, preparing emulsion: soybean oil is used as an oil phase, the oil phase is added into the water phase obtained in the step S2, and the ultrasonic power density is 4000w/cm²Performing ultrasonic treatment for 120s to obtain colloidal emulsion; the volume ratio of the water phase to the oil phase is 1: 0.4.

Technical Field

The invention relates to a preparation method of edible emulsion, in particular to a preparation method of low-oil colloidal emulsion.

Background

The emulsification property of protein is a current research hotspot, and the formed emulsion has great potential development value in the industries of food, medicine and cosmetics. Conventional O/W or W/O emulsions are common. The conventional emulsion has an internal phase volume fraction of 20% to 50%, and is liable to sedimentation and flocculation, which limits its use in various fields. The colloidal emulsion is in a solid state, has the rheological property and high molding property of colloid, and is concerned by various industries in recent years. In addition, the stability of the colloidal emulsion is higher than that of the common emulsion, and the colloidal emulsion has great application value in the aspects of embedding, delivery, moisture retention and the like.

Currently the main colloidal emulsions are monodisperse colloidal emulsions, microlatex liquids and high internal phase colloidal emulsions. The requirement of the high internal phase colloidal emulsion on the interfacial property of the emulsifier is high, the required internal phase volume is large, the manufacturing process is complex, and although the high internal phase colloidal emulsion can replace solid or semisolid grease, the internal phase volume of the high internal phase colloidal emulsion causes potential obesity. For more expensive drugs or active substances, the loading of the high internal phase colloidal emulsion, while advantageous, makes the functional substance more dispersible. The low oil phase colloidal emulsion can release the carried functional substances in a centralized way to achieve the effect. Although the volume fraction of the internal phase of the monodisperse colloidal emulsion and the monodisperse colloidal emulsion is 20-50%, the preparation method is complicated, and either multiple emulsification is needed, or the gel and the emulsion are prepared respectively and then emulsified.

Disclosure of Invention

In order to overcome the defects and shortcomings of the prior art, the invention aims to prepare the colloidal emulsion by using a crude extract of euphausia superba protein as a wall material and soybean oil as an oil phase in a one-step method through high-intensity field ultrasound.

In order to achieve the above object, the present invention provides a method for preparing a low oil colloidal emulsion, comprising the steps of:

s1, preparing a crude euphausia superba protein extract: taking Antarctic krill meat, and beating into meat paste; degreasing the meat paste by using absolute ethyl alcohol to obtain degreased meat paste; removing ethanol in the defatted meat paste, and airing until the water content (m/m) is below 10% to obtain antarctic krill powder; extracting protein in the antarctic krill powder by using an alkali-soluble acid precipitation method to obtain an antarctic krill protein crude extract;

s2, preparing a water phase: redissolving the crude euphausia superba protein extract obtained in the step S1 into a protein solution with the protein concentration of 5-50 mg/ml by using water; stirring and heating the protein solution at the temperature of 80-100 ℃ for 1-2 h, and heating for denaturation to obtain a denatured protein solution; cooling the denatured protein solution to below 25 ℃, and adjusting the pH to 4-5 by using HCl to serve as a water phase; wherein the protein concentration of the protein solution is determined with reference to the biuret method;

s3, preparing emulsion: edible vegetable oil is used as oil phase, the oil phase is added into the water phase in the step S2, premixing is not carried out, and the ultrasonic power density is 4000W/cm²～12000w/cm²Performing ultrasonic treatment for 5-300 s to obtain colloidal emulsion; wherein the volume ratio of the water phase to the oil phase is 1 (0.05-0.40); the non-premixing means that the oil phase and the water phase are not mixed uniformly.

Preferably, the step S1 of preparing the crude euphausia superba protein extract specifically includes: taking Antarctic krill meat, and beating the Antarctic krill meat at 10000-20000 rpm for 2-5 min to form meat paste; mixing the meat paste with absolute ethyl alcohol according to a weight ratio of 1 (7-10), standing for 3-5 h at 25-30 ℃, and stirring once every 15-25 min during standing to fully contact the ethyl alcohol with the meat paste so as to achieve the aim of degreasing; removing ethanol in the meat emulsion, and airing the obtained meat emulsion to obtain antarctic krill powder with the water content (m/m) of less than 10%; mixing the antarctic krill powder with 0.1-0.2N sodium hydroxide solution according to the weight ratio of 1 (9-11), stirring at 38-42 ℃ for 90-110 min at 100-200 rpm, centrifuging at 5500-10000 rpm for 20-30 min, and taking supernatant; and (3) regulating the pH value of the supernatant to 4-5 by using 1-2N hydrochloric acid, standing at 4 ℃ for 20-30 min, centrifuging at 5600-10000 rpm for 20-30 min, and taking a precipitate to obtain the euphausia superba protein crude extract.

In a preferred mode, the step of removing ethanol from the meat paste in the preparation of the crude extract of antarctic krill protein specifically comprises the following steps: the minced meat is leached of ethanol using 8 layers of 100 mesh gauze.

Preferably, the stirring speed in step S2 is 100-200 rpm; the redissolution method of the protein solution with the protein concentration of 5-50 mg/ml comprises the following steps: mixing the crude extract of the antarctic krill protein with deionized water, adjusting the pH to 8-8.5 by using NaOH solution, stirring at 400-500 rpm for 6-12 h, and redissolving into protein solution with the protein concentration of 5-50 mg/ml.

Preferably, the edible vegetable oil in step S3 is soybean oil.

In a preferred embodiment, the method for preparing the low-oil colloidal emulsion comprises the following steps:

s1, preparing a crude euphausia superba protein extract: taking Antarctic krill meat, and beating at 10000rpm for 5min to obtain meat paste; mixing the meat paste and absolute ethyl alcohol according to a weight ratio of 1:8, standing for 4h at 26 ℃, and stirring once every 20min during standing to ensure that the ethyl alcohol and the meat paste are fully contacted so as to achieve the aim of degreasing; then, leaching ethanol in the meat paste by using 8 layers of 100-mesh gauze, and placing the obtained meat paste in a fume hood for 12 hours to obtain antarctic krill powder with the water content (m/m) of 10%; mixing the antarctic krill powder with 0.1N sodium hydroxide solution according to the weight ratio of 1:10, stirring at 40 ℃ and 100rpm for 100min, and centrifuging at 5600rpm for 20 min; taking supernatant, adjusting pH to 4.5 with 1N hydrochloric acid, standing at 4 deg.C for 30min, and centrifuging at 5600rpm for 20 min; taking the precipitate to obtain a crude euphausia superba protein extract;

s2, preparing a water phase: mixing the crude euphausia superba protein extract obtained in the step S1 with deionized water, adjusting the pH to 8 by using NaOH solution, stirring at 450rpm for 8 hours, and redissolving into protein solution with the protein concentration of 50 mg/ml; stirring and heating the protein solution at 100 ℃ and 100rpm for 1h to obtain a denatured protein solution; cooling the denatured protein solution to 25 ℃, and adjusting the pH of the denatured protein solution to 4.5 by using HCl to be used as an aqueous phase; wherein the protein concentration of the protein solution is determined with reference to the biuret method;

s3, preparing emulsion:soybean oil is used as an oil phase, the oil phase is added into the water phase obtained in the step S2, premixing is not carried out, and the ultrasonic power density is 4000w/cm²Performing ultrasonic treatment for 120s to obtain colloidal emulsion; the volume ratio of the water phase to the oil phase is 1: 0.4.

The invention has the beneficial effects that:

1. the invention prepares the colloidal emulsion by a one-step method under the high-intensity ultrasonic condition for the first time without carrying out high-pressure homogenization by a mechanical stirrer. Traditionally, mechanical stirring and high-pressure homogenization are adopted to prepare the emulsion, and the experiment provides a new method for preparing the colloidal emulsion. The colloidal emulsion prepared by the invention has the characteristic particle size of 1-50 mu m, the inside of the emulsion drop is formed by smaller emulsion drops (nano-scale emulsion drops), and the emulsion drops are bridged by filamentous protein.

2. The method for preparing the low-oil colloidal emulsion provides a new direction for preparing the colloidal emulsion and makes up for the defect of complex preparation technology in the prior art.

3. The preparation method provided by the invention can expand the application of the euphausia superba protein in the aspect of emulsion and improve the economic added value of the euphausia superba.

4. The invention is obtained on the basis of repeated experiments, and the properties of the low oil phase emulsion obtained by the method can be obviously influenced by ultrasonic power density, ultrasonic time, pH of a water phase and volume fraction of an oil phase in the emulsion; the ultrasonic power density is 4000W/cm²～12000w/cm²The ultrasonic time is 5-300 s, the pH of the water phase is 4-5, and the volume fraction of the oil phase is 5-40%.

The low-oil colloidal emulsion prepared by the method can be used for replacing solid or semi-solid oil in food processing, and simultaneously avoids potential obesity and health hidden troubles.

Drawings

FIG. 1 is an appearance of a low oil latex prepared in example 1;

FIG. 2 is an appearance of the low oil latex emulsion prepared in example 1 after standing for 0 day;

FIG. 3 is an appearance of the low oil latex emulsion prepared in comparative example 1 after being left at room temperature for 10 days;

FIG. 4 is a stress scan of the low oil latex emulsion prepared in example 1;

FIG. 5 is an appearance of the low oil latex prepared in example 2;

FIG. 6 is an appearance of the low oil latex emulsion prepared in example 2 after standing for 0 day;

FIG. 7 is an appearance of the low oil latex emulsion prepared in comparative example 2 after being left at room temperature for 10 days;

FIG. 8 is a stress scan of the low oil latex emulsion prepared in example 2;

FIG. 9 is an appearance of the low oil latex emulsion prepared in example 3;

FIG. 10 is an appearance of the low oil latex emulsion prepared in example 3 after standing for 0 day;

FIG. 11 is an appearance of the low oil latex emulsion prepared in comparative example 3 after being left at room temperature for 10 days;

FIG. 12 is a stress scan of the low oil latex emulsion prepared in example 3.

Detailed Description

The invention is further illustrated by the following specific examples.

For a better understanding and description of the present invention, the following is a further description of the invention with reference to the drawings and examples, but the embodiments of the invention are not limited thereto.

Unless otherwise specified, the following examples were sonicated using an ultrasonic cell disruptor, model SCIENTZ-IID, manufactured by Ningbo New Ganoderma Biotech Co.