CN107312619A - It is a kind of to improve the method that walnut kernel oil body extracts integrity degree - Google Patents

Abstract

The invention discloses a method for improving the integrity of walnut kernel oil body extraction. The extraction process includes breaking the shell of the walnut, soaking and grinding the walnut kernel, centrifuging and separating the walnut slurry solution, etc., wherein breaking the shell should avoid For the mechanical damage of walnut kernels, the collected walnut kernels are soaked in deionized water, then the walnut kernels are added to the grinding beater containing Tris-HCl buffer solution, and the beating and filtering are performed, and finally the walnut kernel slurry is processed by a centrifuge. After centrifugation, the walnut kernel oil body is collected after standing, and the whole extraction process of the walnut kernel oil body is completed. The extracted oil bodies are observed under an optical microscope. This method can effectively improve the integrity of the walnut kernel oil body extraction, and has a promoting effect on improving the quality of the walnut oil.

Description

A method for improving the integrity of walnut kernel oil body extraction

technical field

The invention relates to a method for improving the integrity of walnut kernel oil body extraction, belonging to the technical field of vegetable oil processing.

Background technique

Many seeds and dried fruits contain high oil content, and these oils are mainly stored in small, independent spherical organelle oil bodies. Oil bodies are also called liposomes and oleosomes. They serve as energy supply stations and are mainly used to support the metabolic activities of cells. Oil bodies are composed of central lipids, mainly triglycerides (TAG), surrounded by a protein-encrusted phosphate outer membrane. Together with the phosphate membrane, the protein stabilizes the oil body structure through surface charges and steric hindrance effects, and protects the oil body as an independent and complete individual. Intact oil bodies are high in unsaturated fatty acids, antioxidants, and have non-agglomerative properties, so they have a wide range of uses in food, biotechnology, and pharmaceutical applications.

The extraction method of walnut kernel oil body in the past mainly includes 3 steps: (1) break up the cell tissue containing oil body, so that oil body is released into the aqueous solution; (2) filter out the tissue except oil body impurities, and obtain a milky white homogenate containing oil bodies; (3) centrifuge the milky white homogenate to collect oil bodies that automatically float to the liquid surface. Breaking, homogenizing and centrifuging the cell tissue containing oil bodies is the key step to obtain complete oil bodies, and the parameters required for different tissues and samples are different. Up to now, the parameters and methods of extracting walnut oil bodies with higher oil content are not very clear.

Contents of the invention

In order to improve the integrity of walnut kernel oil body extraction, the morphological and biochemical characteristics of oil body in walnut kernel cells were studied in the microscopic environment, and finally a method that can improve the integrity of walnut kernel oil body extraction was invented.

The key technology of the present invention is to add a soaking link before grinding and beating the walnut kernels, add a certain amount of buffer reagent to the grinding and beating walnut kernels link, and set the centrifugal force range of the walnut kernel slurry solution. The detailed steps of the method for improving the integrity of walnut kernel oil body extraction are as follows:

Firstly, the walnuts are shelled, and the walnut kernels are protected during the shelling process to avoid mechanical damage to the walnut kernels, and the walnut kernels that have been mechanically damaged are screened and removed;

Weigh the broken walnut kernels, then place the weighed walnut kernels in a clean container, add deionized water 5 to 10 times the quality of the walnut kernels in the container, and dry the walnut kernels at 4°C. Soaking is carried out, and the soaking time is within 6 to 24 hours;

After the walnut kernels are soaked, filter the soaked walnut kernels, put them into a beater or grinder, and add a buffer reagent 5 to 10 times the quality of the walnut kernels. The buffer reagent is 0.1M Tris-HCl, and the pH is 8.0, wherein Contains 0.1mM EDTA;

Using a beater or grinder to crush and beat the walnut kernels added with the buffer reagent, after the crushing and beating is completed, use a filter device to filter out impurities to obtain a milky white homogenate containing oil bodies;

Place the filtered homogenate in a centrifuge, and at an ambient temperature of 4°C, use a centrifuge to centrifuge the milky white homogenate containing oil bodies, set the centrifugal force of the centrifuge in the range of 3000RCF to 7500RCF, and run for 20 minutes;

Let the centrifuged walnut kernel homogenate stand still, collect the oil bodies that automatically float to the surface of the liquid, and complete the whole lifting process of the oil bodies.

In order to test the actual technical effect of this method, compared with the previous walnut kernel oil body extraction process, take 0.1g of the oil body samples obtained by the two methods, add them to 0.5ml deionized water, mix them evenly, and place them under an optical microscope Next, observe the integrity of the oil body size in the two mixtures, and measure the size of the oil body with a particle size measuring device to detect the integrity of the walnut oil body.

By comparing two samples under an optical microscope, it can be found that the oil body particle size extracted by the method of the present invention is smaller and more uniform, and the result of the particle size measuring device also shows that the oil body obtained after soaking the walnut kernel is different from the walnut kernel intracellular oil. The body size remained basically the same. The above comparison results can show that the improved oil body extraction method can promote the improvement of the extraction integrity of walnut kernel oil body.

The present invention optimizes the conventional walnut oil body extraction method, can reduce the degree of damage to walnut kernel cells caused by mechanical grinding, improves the integrity of the walnut kernel oil body, and can further achieve the technical effect of improving the quality of the walnut oil.

Description of drawings

Fig. 1 is the schematic flow sheet of the inventive method

Figure 2 is an electron micrograph of oil bodies when distilled water is used as a buffer

Figure 3 is an electron micrograph of oil bodies when Tris-HCl is used as buffer

Figure 4 is the electron micrograph of the oil body when the centrifugal force is 5500RCF

Figure 5 is the electron micrograph of the oil body when the centrifugal force is 10000RCF

Figure 6 is an electron micrograph of the oil body extracted from walnut kernels without soaking

Figure 7 is an electron micrograph of the oil body extracted from walnut kernels after soaking

detailed description

The technical solution, implementation process, etc. of the present invention will be further described in detail below in conjunction with specific embodiments and accompanying drawings.

Example 1

As shown in Figure (1), a method for improving the integrity of walnut kernel oil body extraction, step (1), crack the walnut shell, pay attention to the protection of the walnut kernel during the shell breaking process, and avoid rubbing the walnut kernel. Injury damage, and the walnut kernels that have been scratched are screened and removed;

Step (2), weighing the walnut kernels after breaking the shell, then placing the weighed walnut kernels in a clean container, adding deionized water 5 to 10 times the quality of the walnut kernels in the container, and heating the walnut kernels at 4°C. Next, soak the walnut kernels for 6 hours;

Step (3), after the walnut kernels are soaked, filter the soaked walnut kernels, put them into a beater or grinder, and add a buffer reagent 5 to 10 times the quality of the walnut kernels, the buffer reagent is 0.1M Tris-HCl , pH 8.0, containing 0.1 mM EDTA;

Step (4), using a beater or grinder to pulverize and beat the walnut kernels added with the buffer reagent, after the pulverization and beating is completed, use a filter device to filter out impurities, and obtain a milky white homogenate containing oil bodies;

Step (5), place the filtered homogenate in a centrifuge, and use a centrifuge to centrifuge the milky white homogenate containing oil bodies at an ambient temperature of 4°C. Set the centrifugal force of the centrifuge to 3000RCF and run for 20 minute;

In step (6), the centrifuged walnut kernel homogenate is left to stand, and the oil bodies that automatically float to the surface of the liquid are collected to complete the whole oil body lifting process.

Example 2

Step (1), step (3), step (4), step (5) and step (6) of the present embodiment are identical with embodiment 1, wherein the parameter setting of step (2) is different;

Step (2), weigh the collected walnut kernels, then place the weighed walnut kernels in a clean container, and add 5 to 10 times the quality of walnut kernels to the container. , soak the walnuts for 12 hours;

Example 3

Step (1), step (3), step (4), step (5) and step (6) of the present embodiment are identical with embodiment 1, wherein the parameter setting of step (2) is different;

In step (2), the collected walnut kernels are weighed, and then the weighed walnut kernels are placed in a clean container, and deionized water with 5 to 10 times the quality of the walnut kernels is added to the container, and heated at 4°C. Next, soak the walnut kernels for 24 hours;

Example 4

Step (1), step (2), step (3), step (4) and step (6) of the present embodiment are identical with embodiment 3, wherein the parameter setting of step (5) is different;

Wherein in step (5), the filtered homogenate is placed in a centrifuge, and at an ambient temperature of 4° C., the walnut kernel slurry solution is centrifuged using a centrifuge, and the centrifugal force of the centrifuge is set to 5500 RCF for 20 minutes.

Example 5

Step (1), step (2), step (3), step (4) and step (6) of the present embodiment are identical with embodiment 3, wherein the parameter setting of step (5) is different;

Wherein in step (5), the filtered solution is placed in a centrifuge, and at an ambient temperature of 4°C, use a centrifuge to centrifuge the milky white homogenate containing oil bodies, set the centrifugal force of the centrifuge to 7500RCF, and run for 20 minute.

Example 6

Step (1), step (3), step (4), step (5) and step (6) of the present embodiment are identical with embodiment 4, wherein the parameter setting of step (2) is different;

In step (2), the collected walnut kernels are weighed, and then the weighed walnut kernels are placed in a clean container, and deionized water with 10 times the quality of the walnut kernels is added to the container. Walnuts are soaked for 12 hours.

Example 7

Step (1), step (3), step (4), step (5) and step (6) of the present embodiment are identical with embodiment 4, wherein the parameter setting of step (2) is different;

In step (2), the collected walnut kernels are weighed, and then the weighed walnut kernels are placed in a clean container, and deionized water with 10 times the quality of the walnut kernels is added to the container. Walnuts are soaked for 24 hours.

The above 7 embodiments have been tested and verified. For the oil body samples prepared according to the embodiments of the present invention, 0.1 g of the samples are taken, added to 0.5 ml of deionized water, mixed evenly, placed under an optical microscope for observation, and Compared with the previous extraction method of walnut kernel oil body, the analysis results are as follows:

Figure 2 is an electron micrograph of the oil body extracted when distilled water is the buffer, and Figure 3 is an electron micrograph of the oil body extracted when Tris-HCl is used as the buffer. Grinding can improve the integrity of the extracted oil bodies.

Figure 4 is the electron micrograph of the oil body extracted when the centrifugal force of the centrifuge is 5500RCF. Improves the integrity of extracted oil bodies.

Fig. 6 is an electron micrograph of extracting oil bodies when walnut kernels are not soaked, and Fig. 7 is an electron micrograph of extracting oil bodies when soaking in deionized water. By comparison under an optical microscope, walnut kernels are soaked in deionized water, which can Improves the integrity of extracted oil bodies.

From the above specific examples and comparative analysis results, it can be concluded that the oil body extraction method of the present invention can greatly improve the integrity of the walnut kernel oil body, thereby improving the quality of walnut oil extracted.

Claims (4)

1. A method for improving the extraction integrity of walnut kernel oil bodies is characterized in that: before walnut kernels are made into walnut kernel slurry, the soaking link is increased, and a certain amount of buffer reagent is added to the grinding and beating link, for the walnut kernel slurry solution The centrifugal force range of the centrifugal link is set, and the specific steps are as follows: (1) Carry out shell breaking process on the raw material walnuts for preparing walnut oil, pay attention to the protection of the walnut kernels in the shell breaking process, avoid causing mechanical damage to the walnut kernels, and screen and remove the damaged walnut kernels in time; (2) Weigh the walnut kernel after breaking the shell, then place the weighed walnut kernel in a clean container, add 5 to 10 times the soaking solution of the walnut kernel mass in the container, and in the environment of 4°C, the Walnuts are soaked; (3) Filter the soaked walnut kernels, place them in a beater or grinder, and add a buffer reagent 5 to 10 times the mass of the walnut kernels; (4) Use a beater or a grinder to pulverize and beat the walnut kernels added with the buffer reagent. After the pulverization is completed, use a filter device to filter out impurities to obtain a milky white homogenate containing oil bodies; (5) Place the milky white homogenate in a centrifuge, and perform centrifugation at 4°C; (6) Leave the milky white homogenate after centrifugation to stand still, collect the oil bodies that automatically float to the liquid surface, and complete the whole oil body extraction process. 2. a kind of method improving walnut kernel oil body extraction integrity according to claim 1, is characterized in that, described soaking solution is deionized water. 3. a kind of method improving walnut kernel oil body extraction completeness according to claim 1 is characterized in that, described buffer reagent is the Tris-HCl of 0.1M, and pH is 8.0, wherein comprises the EDTA of 0.1mM. 4. A method for improving the integrity of walnut kernel oil body extraction according to claim 1, characterized in that the centrifugal force of the centrifugal treatment is controlled within the range of 3000RCF to 7500RCF and runs for 20 minutes.