阅读说明：本技术 一种澳洲坚果油中ω-7脂肪酸纯化及富集方法 (Purification and enrichment method for omega-7 fatty acid in macadamia nut oil ) 是由 何凤平 范建新 周伟 雷朝云 康专苗 袁源 张利 于 2019-09-23 设计创作，主要内容包括：本发明属于脂肪酸提取技术领域,尤其是一种澳洲坚果油中ω-7脂肪酸纯化及富集方法,包括澳洲坚果油制备、混合脂肪酸制备、不饱和脂肪酸分离、ω-7脂肪酸纯化及富集；所述ω-7脂肪酸纯化及富集步骤为：取澳洲坚果油制备所得混合脂肪酸,经低温结晶法分离所得不饱和脂肪酸,加入尿素、乙醇混合均匀,水浴反应2-3h,取出冷却；然后置于特定温度包合一定时间,取出抽滤,收集包合物；向包合物中加入热水溶解,静置分层,取上面油层,饱和氯化钠溶液洗涤,脱水干燥,得到无色的油状液体,即高纯ω-7脂肪酸。本方法简单快捷、效率高且成本低,所得ω-7脂肪酸品质好且纯度高,可大规模的生产。(The invention belongs to the technical field of fatty acid extraction, and particularly relates to a purification and enrichment method of omega-7 fatty acid in macadamia nut oil, which comprises the steps of preparing the macadamia nut oil, preparing mixed fatty acid, separating unsaturated fatty acid, purifying and enriching the omega-7 fatty acid, wherein the purification and enrichment method of the omega-7 fatty acid comprises the steps of taking the mixed fatty acid obtained by preparing the macadamia nut oil, separating the obtained unsaturated fatty acid by a low-temperature crystallization method, adding urea and ethanol, uniformly mixing, reacting in a water bath for 2-3 hours, taking out, cooling, then placing at a specific temperature for inclusion for time, taking out, carrying out suction filtration, collecting the inclusion compound, adding hot water into the inclusion compound for dissolving, standing for layering, taking an upper oil layer, washing with a saturated sodium chloride solution, dehydrating and drying to obtain colorless oily liquid, namely the high-purity omega-7 fatty acid.)

A process for purifying and enriching omega-7 fatty acid from macadamia nut oil includes such steps as preparing macadamia nut oil, preparing mixed fatty acid, separating unsaturated fatty acid, purifying and enriching omega-7 fatty acid, low-temp crystallizing to obtain unsaturated fatty acid, mixing with urea and alcohol, water bath reaction for 2-3 hr, cooling, wrapping at deg.C, suction filtering, collecting the inclusion compound, dissolving in hot water, laying aside, taking oil layer, washing with saturated sodium chloride solution, dewatering and drying to obtain colorless oily liquid, high-purity omega-7 fatty acid.

2. The method of claim 1, wherein the ratio of unsaturated fatty acids: urea: the proportion of ethanol is 1:0.5: 4-1: 2.5:20(g: g: ml), and the optimal proportion is 1:1.5:8(g: g: ml).

3. The method for purifying and enriching omega-7 fatty acids in macadamia nut oil of claim 1, wherein said water bath temperature is 60 ± 5 ℃; the temperature of the hot water is 60 +/-5 ℃.

4. The method for purifying and enriching omega-7 fatty acids in macadamia nut oil according to claim 1, wherein the specific temperature condition is a temperature of-20 ℃ to-5 ℃.

5. The method of claim 1, wherein the separation of the unsaturated fatty acids comprises mixing the fatty acids with ethanol, crystallizing at low temperature for hours, centrifuging, collecting the supernatant, and removing the residual ethanol to obtain the unsaturated fatty acids.

6. The method for purifying and enriching omega-7 fatty acids in macadamia nut oil according to claim 5, wherein the ratio of the mixed fatty acids to ethanol is 1:2 to 1:10(g: ml), and the optimal ratio is 1:6(g: ml).

7. The method of claim 5, wherein the low temperature environment is a temperature of-21 ℃ to 0 ℃.

8. The method for purifying and enriching omega-7 fatty acids in macadamia nut oil according to claim 1, wherein the mixed fatty acid is prepared by: the mixed fatty acid is obtained by saponifying, acidifying and dehydrating the macadamia nut oil.

Technical Field

The invention belongs to the technical field of fatty acid extraction, and particularly relates to a method for purifying and enriching omega-7 fatty acid in macadamia nut oils.

Background

Macadamia nut (Macadamia ternifolia), also called Macadamia nut, queensland fruit and the like, is a perennial evergreen fruit tree of the Macadamia nut genus in the Shanlong ophthalmology, is originally planted in subtropical rainforests of Kunstland, Australian and New south Wales, is introduced into China in the 20 th century in the 60-70 th, and then is vigorously planted in southern areas of China.

In recent years, more and more researches on the function of omega-7 fatty acid show that omega-7 fatty acid has multiple health care functions on human bodies, with the depth of related researches, the nutritional value and the physiological function of omega-7 fatty acid are more and more known, and researches show that omega-7 fatty acid can play a role in organism metabolism as a signal molecule, can improve the sensitivity of human bodies to insulin, has definite efficacy on preventing diabetes, metabolic syndrome and atherosclerosis, can reduce the accumulation of liver fat, reduce inflammation, regulate the cholesterol level in bodies, is beneficial to controlling body weight, maintaining skin health, protecting heart and the like.

Omega-7 fatty acids are groups of straight chain fatty acids containing double bonds, i.e. monounsaturated fatty acids (MUFA), including 5-dodecenoic acid (12:1, omega-7), 7-tetradecenoic acid (14:1, omega-7), palmitoleic acid (16:1, omega-7), vaccenic acid (18:1, omega-7), 13-eicosenoic acid (20:1, omega-7), 15-docosenoic acid (22:1, omega-7) and 17-tetracosenoic acid (24:1, omega-7), omega-7 fatty acids in macadamia nut oil are palmitoleic acid and vaccenic acid, which are low in content, only around 16%, and therefore how to obtain high purity omega-7 fatty acids from macadamia nut oil by technical means is a key factor affecting its high-valued application.

For example, patent application No. CN201710920137.2 discloses methods for extracting palmitoleic acid from natural vegetable oil, which include the steps of 1) dissolving alkali in water to perform catalytic hydrolysis reaction on the vegetable oil, wherein the mass ratio of the alkali to the water to the oil is 0.1-0.6: 2-8: 1, 2) subjecting the product obtained in the step 1) to multistage molecular distillation to receive light components, 3) subjecting the light components obtained in the step 2) to solvent crystallization, wherein the ratio of the light components to the solvent is 1:1-20, and recovering a solution layer after suction filtration.

Also, for example, CN201610412141.3 discloses a method for extracting palmitoleic acid from sea buckthorn fruit oils, which comprises the steps of saponifying a sea buckthorn fruit oil sample to obtain saponified mixed fatty acid of the sea buckthorn fruit oil, mixing urea with a common organic solvent, stirring and refluxing the mixture until the urea is completely dissolved, adding the mixed fatty acid of the sea buckthorn fruit oil, refluxing and extracting the mixture for 30-120min, cooling the mixture to room temperature, embedding the mixture for crystallization, rapidly performing suction filtration, removing the common organic solvent from the filtrate, removing the urea to obtain a fatty acid sample, treating the fatty acid sample obtained by embedding the urea, and separating out light components with long average free path under the conditions that the pressure is 0.1-0.2Pa, the distillation temperature is 70-140 ℃, the feeding rate and the film scraping rotation speed guarantee that a uniform film can be formed, thereby obtaining palmitoleic acid.

The methods provided by the patents all adopt molecular distillation technology, and special molecular distillation equipment of is needed, so that the cost is high.

For example, CN201811607339.2 discloses methods for separating and preparing trans-palmitoleic acid from fish oil, which comprise the steps of saponifying fish oil to obtain saponified mixed free fatty acid, performing urea inclusion polymerization in an organic solvent to include saturated fatty acid and monounsaturated fatty acid in the mixed fatty acid, performing low-temperature urea crystallization to separate urea inclusion and solid, performing de-inclusion polymerization in the organic solvent or an acidic solvent or at an elevated temperature to obtain a mixture of saturated fatty acid and monounsaturated fatty acid, performing column chromatography to separate trans-palmitoleic acid, wherein a column chromatography technology is adopted, a column chromatography device special for is required, the cost is high, and the separation time is long.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention provides a method for purifying and enriching omega-7 fatty acid in kinds of macadamia nut oil, which is simple, quick, high in efficiency and low in cost, and is realized by the following technical scheme:

A method for purifying and enriching omega-7 fatty acid in macadamia nut oil, which comprises the following steps:

(1) preparation of macadamia nut oil: shelling macadimia nuts, crushing nuts, and physically squeezing to obtain macadimia nut oil;

(2) preparing mixed fatty acid: the macadamia nut oil is saponified, acidified, dehydrated and dried to obtain mixed fatty acid;

(3) unsaturated fatty acid separation (low temperature crystallization): weighing the mixed fatty acid, and mixing the following components in percentage by weight: adding ethanol into the mixture in a ratio of 1: 2-1: 10(g: ml), uniformly mixing, standing at a low temperature (-21-0 ℃) for crystallization for 8-24 hours, centrifuging, collecting supernate, and removing residual ethanol to obtain unsaturated fatty acid.

(4) Omega-7 fatty acid purification and enrichment (urea inclusion): taking the unsaturated fatty acid, and mixing the unsaturated fatty acid: urea: adding urea and ethanol into ethanol at a ratio of 1:0.5: 4-1: 2.5:20(g: g: ml), carrying out water bath at 60 +/-5 ℃ for 2-3h, taking out and cooling to room temperature; then putting the mixture into a temperature of between 20 ℃ below zero and 5 ℃ below zero for inclusion for 6 to 30 hours, taking out the mixture for suction filtration, and collecting an inclusion compound; dissolving in 60 + -5 deg.C hot water, standing for layering, collecting the upper oil layer, washing with saturated sodium chloride solution, and dehydrating to obtain colorless oily liquid, i.e. high purity omega-7 fatty acid.

Preferably, in the step (3), the fatty acid mixture: the proportion of ethanol is 1:6(g: ml).

Preferably, in the step (4), the ratio of unsaturated fatty acid: urea: the proportion of ethanol is 1:1.5:8(g: g: ml).

In the step (2), the preparation of the mixed fatty acid specifically comprises the following steps:

a. saponification: adding macadamia nut oil into an ethanol solution containing 2-4% of NaOH for saponification, refluxing in a water bath at 80 +/-5 ℃ for 2-3 hours, cooling to room temperature after the saponification is finished, transferring into a separating funnel, adding a proper amount of n-hexane for extraction, standing for layering, and taking a lower-layer water phase; wherein the ratio of the macadamia nut oil to the ethanol solution is 1:4(g: ml);

b. acidifying: and adding 10-20% HCl into the lower-layer water phase for acidification, adjusting the pH value to 2-3, transferring the mixture into a separating funnel, adding a proper amount of n-hexane for extraction, standing for layering, and taking an upper-layer organic phase.

c. And (3) dehydration and drying treatment: washing the upper organic phase with saturated salt solution to neutrality, dewatering with anhydrous sodium sulfate, drying, vacuum filtering, and removing organic solvent to obtain mixed fatty acid.

d. The invention has the beneficial effects that:

1. the method of combined use of low-temperature crystallization and urea inclusion can purify and enrich high-purity omega-7 fatty acid from mixed fatty acid of macadamia nut oil, does not need special molecular distillation equipment and column separation equipment of , and greatly reduces the production cost of omega-7 fatty acid.

2. The recovery rate and purity of omega-7 fatty acid purified and enriched from the macadamia nut oil are high; the recovery rate of omega-7 fatty acid can reach more than 60%, and the purity of omega-7 fatty acid can reach more than 70%.

3. The method is simple and rapid, has high efficiency and low cost, and the obtained omega-7 fatty acid has good quality and high purity and can be produced on a large scale.

Drawings

FIG. 1 shows mixed fatty acids in different ratios: influence of ethanol on the recovery and purity of unsaturated fatty acids.

FIG. 2 shows unsaturated fatty acids in different ratios: effect of urea on omega-7 recovery and purity.

FIG. 3 shows unsaturated fatty acids in different ratios: influence of ethanol on omega-7 recovery and purity.

Detailed Description

The invention is further defined in step with reference to the following detailed description, but the scope of the claims is not limited to the description.