阅读说明：本技术 一种从牛腩中提取亚油酸的方法 (Method for extracting linoleic acid from sirloin ) 是由 谭春萍 黄广君 唐榕 程忠 黄福标 黄春兰 于 2019-10-30 设计创作，主要内容包括：本发明公开了一种从牛腩中提取亚油酸的方法,包括牛腩预处理、酶解、浸提、离心、萃取、结晶、萃取等步骤。本申请首次提出从牛腩中提取亚油酸,并给出了具体的提取方法,使牛腩能够得到充分再利用,为牛腩的研究提供了新思路；且操作简单,亚油酸的提取率高,降低了提取成本。(The invention discloses a method for extracting linoleic acid from sirloin, which comprises the steps of sirloin pretreatment, enzymolysis, leaching, centrifugation, extraction, crystallization, extraction and the like. The application firstly provides the extraction of linoleic acid from sirloin and provides a specific extraction method, so that the sirloin can be fully recycled, and a new idea is provided for the research of the sirloin; and the operation is simple, the extraction rate of the linoleic acid is high, and the extraction cost is reduced.)

1. A method for extracting linoleic acid from sirloin is characterized by comprising the following steps:

(1) pre-treating sirloin: cleaning sirloin with cold water, drying at 70-75 ℃ until the water content is 20-25%, and micronizing in a micronizer to obtain sirloin powder;

(2) enzymolysis: adding clear water with the weight 0.75-0.85 times of that of the sirloin powder in the step (1), adding pepsin for enzymolysis for 100-120 min, carrying out microwave treatment for assisting enzymolysis, then inactivating enzyme at 65-70 ℃, adding trypsin for enzymolysis for 90-100 min, carrying out ultrasonic treatment for assisting enzymolysis, centrifuging, filtering and collecting filter residues;

(3) leaching and centrifuging: adding an n-hexane solution into the filter residue obtained in the step (2), refluxing and leaching, and centrifuging and filtering to remove residues to obtain sirloin oil;

(4) and (3) extraction: adding NaOH ethanol solution into the sirloin oil obtained in the step (3), heating and stirring at 88-95 ℃ for reaction for 115-125 min, cooling to room temperature, adding 1mol/L hydrochloric acid solution to adjust the pH value to 2-3 under a stirring state, adding petroleum ether for extraction and separation, washing the upper layer to be neutral by using water, performing rotary evaporation to recover solvent petroleum ether, and removing moisture by using anhydrous sodium sulfate to obtain mixed fatty acid;

(5) crystallization and extraction: heating an absolute ethyl alcohol solution to 65-70 ℃, adding urea while stirring to completely dissolve the urea in the ethyl alcohol, then adding the mixed fatty acid obtained in the step (4), heating, stirring, refluxing, cooling to room temperature, freezing, crystallizing, filtering, washing and extracting crystals by using n-hexane, washing an organic phase by using water until no urea exists, removing water by using anhydrous sodium sulfate, and recovering the organic solvent by rotary evaporation to obtain linoleic acid.

2. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (1), the frequency of the superfine grinding is 0.01-0.05 KHz, the wind speed is 1.2-1.5 m/s, the time is 15-20 min, and the granularity of the ground material is 20-25 μm.

3. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (2), the adding amount of the pepsin is 2-3% of the weight of the sirloin powder; the adding amount of the trypsin is 1.5-2.5% of the weight of sirloin powder.

4. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (2), the frequency of the microwave treatment is 0.05-0.1 KHz, the power is 500-550W, and the time is 80-100 min.

5. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (2), the frequency of ultrasonic treatment is 0.2-0.3 Mpa, the power is 500-600W, and the time is 10-15 min, and during the ultrasonic treatment, the ultrasonic wave is operated for 20-22 min and is suspended for 1-2 min within 90-100 min of enzymolysis.

6. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (3), the temperature of the reflux extraction is 65-70 ℃, and the time is 7.5-8.5 h; the rotating speed of the centrifugation is 6000-6500 r/min, and the time is 30-35 min.

7. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (4), the mass concentration of the NaOH ethanol solution is 4-6%, and the adding amount of the NaOH ethanol solution is 4.5-5.5 times of that of the sirloin oil.

8. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (5), the mass ratio of the urea to the absolute ethyl alcohol is 1: 18-20; the mass ratio of the mixed fatty acid to the urea is 1.5-3: 1.

9. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (5), the heating, stirring and refluxing temperature is 60-65 ℃, the time is 30-35 min, and the stirring speed is 350-400 r/min.

10. The method for extracting linoleic acid from sirloin according to claim 1, wherein: in the step (5), the temperature of the freezing crystallization is-10-3 ℃, and the time is 10-15 h.

Technical Field

The invention belongs to the technical field of production and processing of health-care products, and particularly relates to a method for extracting linoleic acid from sirloin.

Background

Linoleic acid, a fatty acid, cis-9, 12-octadecadienoic acid. Linoleic acid is present in animal and vegetable fats and oils in the form of glycerides together with other fatty acids, and is a main component of linseed oil, drying oil such as cottonseed oil, and semi-drying oil in the form of glycerides. The inability of the human body to synthesize linoleic acid, or to synthesize fatty acids in far from adequate amounts, is called essential fatty acid. Linoleic acid is recognized as an essential fatty acid. Linoleic acid is considered important for lowering blood cholesterol and preventing atherosclerosis. It has been found that cholesterol must be bound to linoleic acid before proper functioning and metabolism can occur in vivo. If the linoleic acid is lacked, cholesterol is combined with some saturated fatty acids, metabolic disorder occurs, the cholesterol is deposited on the blood vessel wall, atherosclerosis is gradually formed, and cardiovascular and cerebrovascular diseases are caused.

Sirloin refers to a meat mass with tendons, meat and oil flowers, namely loose and soft muscles at the abdomen and near the ribs of a cow, which is a general name. According to the parts, the meat in many parts of the body of a cow can be called sirloin. The upper layer of the fillet has a fillet with less ribs, less oil and more meat, but the fillet with a less regular shape may be called sirloin and is the first-class red-cooked part. The beef tendon can be one of sirloin, has more tendon and meat and less oil, even is lean meat, is generally used for marinating, is not suitable for stewing and is not suitable for braising.

Sirloin provides high quality protein, contains all kinds of amino acids, the proportion of each amino acid is basically consistent with that of each amino acid in human protein, and the contained sarcosine is higher than that of any food; low fat content, but a source of low fat linoleic acid, or a potential antioxidant; contains minerals and vitamin B group, including niacin, vitamin B1, and riboflavin. Beef is the best source of iron needed daily. Sirloin is sweet in flavor and mild in nature; spleen and stomach meridians entered; the beef has the effects of tonifying spleen and stomach, replenishing qi and blood, strengthening bones and muscles, eliminating edema and the like. The elderly eat beef and cactus together, and have effects of resisting cancer, relieving pain, and improving immunity; the beef and the red date are stewed for taking, so that the beef soup has the effects of promoting muscle growth and promoting wound healing.

Linoleic acid is an unsaturated fatty acid, and the extraction method is more, and the prior published documents for extracting linoleic acid from cattle bodies are less, and patent application CN201910173201.4 discloses an extraction method of linoleic acid in achyranthes bidentata leaves, belonging to the technical field of extraction of linoleic acid. The technical scheme provided by the invention has the key points that: drying and crushing achyranthes bidentata leaves, leaching by normal hexane, saponifying, and carrying out urea inclusion at low temperature to obtain linoleic acid. The method for extracting linoleic acid from achyranthes bidentata leaves, provided by the invention, has the advantages of simple operation, good extraction rate of linoleic acid, low price of used reagents, wide sources and easy obtainment, and provides a new idea for the research of a production process of linoleic acid and the development and utilization of achyranthes bidentata leaves.

Multiple research data show that linoleic acid can obviously reduce the level of blood fat, soften small and medium blood vessels, alleviate blood pressure, increase blood circulation, indirectly recover nerve function and the like, can prevent or reduce the incidence of cardiovascular and cerebrovascular diseases, is particularly favorable for preventing and treating hypertension, hyperlipidemia, angina pectoris, coronary heart disease, atherosclerosis, senile obesity and the like, can prevent the deposition of serum cholesterol in the blood vessel wall of a human body, has the reputation of 'blood vessel scavenger', and has the health-care effect of preventing and treating atherosclerosis and cardiovascular diseases.

However, no literature is found to disclose how to extract linoleic acid from sirloin, and therefore, it is important to develop a method for extracting linoleic acid from sirloin.

Disclosure of Invention

The invention provides a method for extracting linoleic acid from sirloin to solve the technical problems. The application firstly provides the extraction of linoleic acid from sirloin and provides a specific extraction method, so that the sirloin can be fully recycled, and a new idea is provided for the research of the sirloin; and the operation is simple, the extraction rate of the linoleic acid is high, and the extraction cost is reduced.

In order to achieve the above purpose, the invention adopts the following technical scheme:

a method for extracting linoleic acid from sirloin comprises the following steps:

(1) pre-treating sirloin: cleaning sirloin with cold water, drying at 70-75 ℃ until the water content is 20-25%, and micronizing in a micronizer to obtain sirloin powder;

(2) enzymolysis: adding clear water with the weight 0.75-0.85 times of that of the sirloin powder in the step (1), adding pepsin for enzymolysis for 100-120 min, carrying out microwave treatment for assisting enzymolysis, then inactivating enzyme at 65-70 ℃, adding trypsin for enzymolysis for 90-100 min, carrying out ultrasonic treatment for assisting enzymolysis, centrifuging, filtering and collecting filter residues;

(3) leaching and centrifuging: adding an n-hexane solution into the filter residue obtained in the step (2), refluxing and leaching, and centrifuging and filtering to remove residues to obtain sirloin oil;

(4) and (3) extraction: adding NaOH ethanol solution into the sirloin oil obtained in the step (3), heating and stirring at 88-95 ℃ for reaction for 115-125 min, cooling to room temperature, adding 1mol/L hydrochloric acid solution to adjust the pH value to 2-3 under a stirring state, adding petroleum ether for extraction and separation, washing the upper layer to be neutral by using water, performing rotary evaporation to recover solvent petroleum ether, and removing moisture by using anhydrous sodium sulfate to obtain mixed fatty acid;

(5) crystallization and extraction: heating an absolute ethyl alcohol solution to 65-70 ℃, adding urea while stirring to completely dissolve the urea in the ethyl alcohol, then adding the mixed fatty acid obtained in the step (4), heating, stirring, refluxing, cooling to room temperature, freezing, crystallizing, filtering, washing and extracting crystals by using n-hexane, washing an organic phase by using water until no urea exists, removing water by using anhydrous sodium sulfate, and recovering the organic solvent by rotary evaporation to obtain linoleic acid.

Further, in the step (1), the frequency of the superfine grinding is 0.01-0.05 KHz, the wind speed is 1.2-1.5 m/s, the time is 15-20 min, and the granularity of the ground material is 20-25 mu m.

Further, in the step (2), the adding amount of the pepsin is 2-3% of the weight of the sirloin powder; the adding amount of the trypsin is 1.5-2.5% of the weight of sirloin powder.

Further, in the step (2), the frequency of the microwave treatment is 0.05-0.1 KHz, the power is 500-550W, and the time is 80-100 min.

Further, in the step (2), the frequency of ultrasonic treatment is 0.2-0.3 Mpa, the power is 500-600W, and the time is 10-15 min, and during the ultrasonic treatment, the ultrasonic treatment is performed in a mode of operating for 20-22 min and pausing for 1-2 min within 90-100 min of enzymolysis.

Further, in the step (3), the temperature of the reflux leaching is 65-70 ℃, and the time is 7.5-8.5 h; the rotating speed of the centrifugation is 6000-6500 r/min, and the time is 30-35 min.

Further, in the step (4), the mass concentration of the NaOH ethanol solution is 4-6%, and the adding amount of the NaOH ethanol solution is 4.5-5.5 times of the sirloin oil.

Further, in the step (5), the mass ratio of the urea to the absolute ethyl alcohol is 1: 18-20; the mass ratio of the mixed fatty acid to the urea is 1.5-3: 1.

Further, in the step (5), the heating, stirring and refluxing temperature is 60-65 ℃, the time is 30-35 min, and the stirring speed is 350-400 r/min.

Further, in the step (5), the temperature of the frozen crystals is-10-3 ℃ and the time is 10-15 hours.

Due to the adoption of the technical scheme, the invention has the following beneficial effects:

(1) the application firstly provides the extraction of linoleic acid from sirloin and provides a specific extraction method, so that the sirloin can be fully recycled, and a new idea is provided for the research of the sirloin; and the operation is simple, the extraction rate of the linoleic acid is high, and the extraction cost is reduced.

(2) China is the third breeding and producing country in the beef cattle breeding and beef production world after the United states and Brazil, and the stock market of beef cattle in China keeps a stable and low-speed growth situation in recent years, but the sirloin at present is only used for meat, and the commodity value is low; the linoleic acid extracted by the method has the effects of reducing blood fat, softening blood vessels, reducing blood pressure and promoting microcirculation, can prevent or reduce the incidence rate of cardiovascular diseases, and is particularly favorable for preventing and treating hypertension, hyperlipidemia, angina pectoris, coronary heart disease, atherosclerosis, senile obesity and the like, so that the utilization value of the sirloin is improved after the sirloin is extracted by the method.

Detailed Description

The following is a detailed description of the embodiments of the present invention, but the present invention is not limited to these embodiments, and any modifications or substitutions in the basic spirit of the embodiments are included in the scope of the present invention as claimed in the claims.