WO2014071736A1

WO2014071736A1 - Method for extracting silkworm pupa oil

Info

Publication number: WO2014071736A1
Application number: PCT/CN2013/077521
Authority: WO
Inventors: 张耀洲; 王玉芳; 陈剑清; 舒特俊
Original assignee: 天津耀宇生物技术有限公司
Priority date: 2012-11-09
Filing date: 2013-06-20
Publication date: 2014-05-15
Also published as: CN102965189A

Abstract

A method for extracting silkworm pupa oil from a silkworm pupa by means of a homogenization process, comprising the steps of pretreating the silkworm pupa, homogenized extraction, silkworm pupa oil preparation, silkworm pupa oil refining and so on.

Description

FIELD OF THE INVENTION The present invention relates to the field of food processing technology, and particularly relates to a method for extracting silkworm pupa oil by using a silkworm pupa as a raw material. Background technique

Natural oils and fats are widely found in animals and plants. They are contained in the body of animals, such as butter, lard, and sheep oil. Among the plants, there are perilla oil, linseed oil, and evening primrose oil. Grease is not only one of the main substances that human beings depend on, but also an important industrial raw material, and has a wide range of uses in the fields of food, medicine, cosmetics, leather industry and the like. China's oil and fat resources are seriously inadequate. China's three major edible oils, such as soybean oil, palm oil and rapeseed oil, rank first in the world, and total imports account for 18% of global trade. Therefore, experts have called for increased oil development, increased oil extraction rates, and increased oil production.

Silkworm cocoon is a kind of medicine and food. It is the main by-product of the silk industry. It can produce 1.5 tons of dried silkworm cocoons per ton of raw silk. The silkworm cocoons are the most abundant stage of storage during the metamorphosis of silkworms. A variety of natural active substances and pheromones are energy sources that support the emergence, flight, reproduction and embryonic development of silkworm moths, with very important nutritional value and health care functions. China is a major producer of silkworm. Domestically, more than 200,000 tons of silkworm cocoons are available every year. However, due to the lack of deep processing technology, they are basically used as feed or fertilizer, and the resource utilization rate is low, resulting in great waste. In view of the important nutritional value and health care function of silkworm pupa, the Ministry of Health has identified it as a new resource for nutritious food. Silkworm pupa oil is a mixture of various high-grade fatty acid glycerides extracted from silkworm pupa. It has a yellow to red transparent oily liquid. The content of unsaturated fatty acids in silkworm pupa oil is very high, about 75%, rich in essential linoleic acid and α-linolenic acid, etc., its content is about: oleic acid 33%, α-linolenic acid 35%, sub 8 % oleic acid, functional and nutritional studies at home and abroad have shown that alpha-linolenic acid has important protection Health function: Reduce blood lipids, cholesterol and blood pressure, prevent cardiovascular disease; inhibit platelet aggregation, prevent thrombosis and stroke; enhance retinal reflex ability, prevent vision deterioration; enhance memory. Therefore, silkworm cocoon oil products can be used to improve and prevent diseases such as hyperlipemia, hyperglycemia, and hypertension. Approved by the State Food and Drug Administration, the pharmaceutical industry has developed new drugs with antihypertensive, lipid-lowering and liver-protecting functions using silkworm cocoons as raw materials. Experts from the World Health Organization have shown that the α-linolenic acid rich in silkworm pupa is an essential carbon fatty acid in the human body, which is metabolized in the human body to produce sputum, DHA and prostacyclin.

The extraction method of silkworm pupa oil mainly includes pressing method, including raw pressing method, hot pressing method, boiling pressing method and leaching method, also known as extraction method and Soxhlet fat extraction method and supercritical method, but the silkworm pupa is high protein. Highly lipid substances, the protein after extracting oil by pressing method has been denatured, and the content of crude fiber in silkworm cocoons is less, the texture is softer, the oil yield of pressing is very low, and the pressing method is not convenient. The use of Soxhlet fat extraction is not only time-consuming and labor-intensive, but also requires the heating in the extraction process, which also affects the quality of the proposed grease. The organic solvent extraction method has low cost and low energy consumption, but has the disadvantages of long extraction time and low extraction rate; supercritical carbon dioxide extraction has high extraction rate and short extraction time, but requires high equipment and high energy consumption, and homogenization. The method-assisted extraction method has not been reported in the extraction of silkworm pupa oil, which effectively shortens the extraction time, and is easy to operate and easy to grasp. Homogenization enhances the rate and effect of the extraction process, which facilitates the extraction of oil. Summary of the invention

In order to overcome the deficiencies in the prior art of extracting silkworm cocoon oil, the present invention provides a method for extracting silkworm pupa oil from silkworm pupa by a homogenization method with simple operation, high extraction rate, short extraction time and low production cost.

In order to solve the problem, the specific technical solutions adopted by the present invention are as follows:

(a) Cocoon pretreatment:

The wet silkworm cocoons are placed in a blast drying oven at 120 ° C for 12 h to dry until the water content is less than 8%. (b) Homogenization extraction:

Weigh a certain amount of silkworm cocoon powder into the homogenizer, add the corresponding proportion of extraction solvent, the mass ratio of silkworm cocoon powder to extraction solvent is 1: 3~6, start the homogenizer homogenate 6 times, each time 5 minutes, A total of 30 minutes, the speed is 6000 ~ 18000rpm / min, collecting the homogenate;

(c) Preparation of silkworm pupa oil:

The extract is filtered with 4~8 layers of gauze. The filtrate is collected and centrifuged at 4000 ~ 8000 rpm/min for 10~30 minutes. The supernatant is collected and the supernatant is placed in a vacuum filter at room temperature. The filtrate was obtained by vacuum filtration at -0.08 MPa, and the filtrate was distilled under reduced pressure in a vacuum evaporator at 60-80 ° C and -0.08 MPa to recover the extraction solvent, and the residue was removed in an oven at 40 to 50 ° C. Extracting the solvent to obtain silkworm oil;

(d) Refined silkworm oil:

After heating the silkworm pupa oil obtained in the step (c) to 70 ° C, add citric acid crystals (C ₆ H ₈ 0 ₇ 3⁄40) which are 0.05% -0.12 % of the silkworm pupa oil, and after mixing, let stand for 5-6 minutes, The divalent metal ions Ca ²⁺ , Mg ²⁺ , and Fe ²⁺ such as calcium, magnesium, and iron remaining in the silkworm pupa oil are brought into a free state and moved to the aqueous phase. After centrifugation at 3000~4000rpm/min, it is removed to achieve the purpose of degumming. The acid value can not be higher than 0.2 mgKOH/g. Under the condition of considering the soap foot and color, the super alkali content of the refining silkworm oil is determined. 74.4%, at this time the hardness of the soap angle is suitable, the oil soap is easy to separate, the acid value and the color are all required; when the initial temperature of the oil is 45 ° C; adding a mass fraction of 14% potassium hydroxide aqueous solution, mixing and stirring 30 ~ 40 In the minute and continue to heat up until the temperature of the silkworm cocoon oil is controlled at 60 ~ 65 °C, the oil soap is quickly centrifuged at 3000~4000rpm/min, the upper layer of oil is removed, and the washing is stirred at 120 rpm/min with 80 °C distilled water until the washing liquid The pH value is neutral and the purpose of deacidification is achieved. The decolorized white clay which accounts for 4% of the silkworm pupa oil is added to the silkworm pupa oil after deacidification. The temperature of the silkworm pupa oil is controlled at 40 ~ 42 °C, stirred for 30 minutes, and the bleached white clay is separated by filtration. Refined silkworm cocoon oil.

Further, the mass ratio of the silkworm pupa powder to the extraction solvent in the above step (b) is 1:4-6. Further, the mass ratio of the silkworm meal to the extraction solvent in the above step (b) is 1:4.

Further, the solvent extracted in the above step (b) is petroleum ether, ethyl acetate or absolute ethanol. Further, in the above step (b), the rotational speed of the homogenizer is 6000 to 8000 rpm/min.

The invention has the advantages that the invention has the advantages of simple process steps, high extraction rate, short extraction time and low production cost, and can be used for preparing silkworm pupa oil from silkworm pupa. The prepared silkworm pupa oil has a yellow color and oily aroma. The indexes meet the quality standards of silkworm pupa oil reported in the literature, and can be used as an edible oil or as a health food base. detailed description

It should be noted that the following detailed description is illustrative and that further inventions are provided. Unless otherwise stated, all scientific and technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

The present invention will be further described below in conjunction with the embodiments. However, the invention is not limited to these embodiments. Example 1

Taking silkworm pupa powder 100g as the raw material for the extraction of silkworm pupa oil, the extraction method is as follows:

(a) Cocoon pretreatment

The wet silkworm cocoons are placed in a blast drying oven at 120 ° C for 12 hours and dried until the water content is less than 8%.

(b) Homogenization extraction

Weigh 100g of silkworm cocoon powder into the homogenizer, add 400g petroleum ether (extraction solvent), the mass ratio of silkworm cocoon powder to petroleum ether is 1: 4, start the homogenizer homogenate 6 times, each time 5 minutes, total The homogenate was collected for 30 minutes at a speed of 8000 rpm.

(c) Preparation of silkworm cocoon oil

The obtained homogenate was filtered through 4 to 8 layers of gauze, and the filtrate was collected and centrifuged at 4000 to 8000 rpm/min for 10 to 30 minutes. The supernatant was collected and the supernatant was placed in a vacuum filter. The filtrate was filtered under reduced pressure at -0.08 MPa at room temperature to obtain a filtrate; the filtrate was distilled under reduced pressure at 60-80 ° C, -0.08 MPa in a vacuum evaporator, and the extraction solvent was recovered in an oven at 40 to 50 ° C. The residue extraction solvent is removed to obtain silkworm oil.

(d) refining silkworm cocoon oil

Add citric acid crystals (C ₆ H ₈ 0 ₇ -H ₂ 0 ) which are 0.05% of silkworm pupa oil to the silkworm pupa oil heated to 70 °C. After mixing, let stand for 5-6 minutes, which will remain in the silkworm pupa oil. Calcium, magnesium, iron and other divalent metal ions Ca ²⁺ , Mg ²⁺ , Fe ²⁺ become free, move to the aqueous phase, and then centrifuged at 3000 ~ 4000 rpm / min to remove, thereby achieving the purpose of degumming The acid value can not be higher than 0.2 mgKOH/g. Under the condition of considering the soap foot and color, the super alkali content of the refined silkworm oil is determined to be 74.4%. At this time, the hardness of the soap angle is suitable, the oil soap is easy to separate, and the acid value is And the color is up to the requirement; when the initial temperature of the oil is 45 °C; add a potassium hydroxide aqueous solution with a mass fraction of 14%, mix and stir for 30 to 40 minutes and continue to heat up until the temperature of the silkworm cocoon is controlled at 60 ~ 65 °C. Then, the oil soap is quickly centrifuged by 3,000-4000 rpm/min, the upper layer of oil is removed, and the mixture is washed with 120 ° C distilled water at 120 rpm/min until the pH of the washing liquid is neutral, and the purpose of deacidification is achieved; After the addition of 4% of the quality of the silkworm pupa oil, the silkworm pupa oil Controlled at 40 ~ 42 ° C, stirred for 30 minutes, bleaching clay was separated by filtration to obtain refined oils pupa.

Example 2

(a) Cocoon pretreatment

(b) Homogenization extraction

Weigh 100g of silkworm cocoon powder into the homogenizer, add 500g petroleum ether (extraction solvent), the mass ratio of silkworm cocoon powder to petroleum ether is 1:5, start the homogenizer homogenate 6 times, each time 5 minutes, total The homogenate was collected for 30 minutes at a speed of 8000 rpm. (C) Preparation of silkworm pupa oil

The obtained homogenate is filtered with 4 ~ 8 layers of gauze, the filtrate is collected, centrifuged at 4000 ~ 8000 rpm / min for 10 ~ 30 minutes, the supernatant is collected, and the supernatant is placed in a vacuum filter at room temperature. The filtrate was filtered under reduced pressure at -0.08 MPa to obtain a filtrate; the filtrate was distilled under reduced pressure at 60-80 ° C and -0.08 MPa in a vacuum evaporator to recover the extraction solvent, and the residue was removed in an oven at 40 to 50 ° C. The solvent is extracted and the silkworm oil is obtained.

(d) refining silkworm cocoon oil

After the obtained silkworm pupa oil is heated to 70 ° C, the citric acid crystal ( C ₆ H ₈ 0 ₇ -H ₂ 0 ) which accounts for 0.08 % of the silkworm pupa oil is added, and after mixing, it is allowed to stand for 5-6 minutes, which will remain in the silkworm pupa oil. Calcium, magnesium, iron and other divalent metal ions Ca ²⁺ , Mg ²⁺ , Fe ²⁺ become free, move to the aqueous phase, and then centrifuged at 3000 ~ 4000 rpm / min to remove, thereby achieving the purpose of degumming The acid value can not be higher than 0.2 mg KOH / g as the standard, in the case of comprehensive consideration of soap feet and color, the determination of the super alkali content of the refining silkworm pupa oil is 74.4%, at this time the hardness of the saponin angle is suitable, the oil soap is easy to separate, The acid value and color are all required. When the initial temperature of the oil is 45 °C, add a potassium hydroxide solution with a mass fraction of 14%, mix and stir for 30 to 40 minutes and continue to heat up until the temperature of the silkworm cocoon is controlled at 60 ~ 65 °C. At the same time, the oil soap is quickly centrifuged by 3,000 ~ 4000 rpm / min, the upper layer of grease is removed, and the mixture is stirred and washed at 120 rpm/min with 80 ° C distilled water until the pH of the washing liquid is neutral, and the purpose of deacidification is achieved; Adding decolorized white clay, which accounts for 4% of the quality of silkworm pupa oil, to the silkworm pupa oil after deacidification, silkworm pupa The oil temperature is controlled at 40 ~ 42 °C, stirred for 30 minutes, and the decolorized white clay is separated by filtration to obtain refined silkworm oil.

Example 3

(a) Cocoon pretreatment

(b) Homogenization extraction Weigh 100g of silkworm cocoon powder into the homogenizer, add 600g petroleum ether (extraction solvent), the mass ratio of silkworm cocoon powder to petroleum ether is 1:6, start the homogenizer homogenate 6 times, each time 5 minutes, total The homogenate was collected for 30 minutes at a speed of 8000 rpm.

(c) Preparation of silkworm cocoon oil

(d) refining silkworm cocoon oil

After the obtained silkworm pupa oil is heated to 70 ° C, the citric acid crystal ( C ₆ H ₈ 0 ₇ -H ₂ 0 ) which accounts for 0.12% of the silkworm pupa oil is added, and after mixing, it is allowed to stand for 5-6 minutes, which will remain in the silkworm pupa oil. Calcium, magnesium, iron and other divalent metal ions Ca ²⁺ , Mg ²⁺ , Fe ²⁺ become free, move to the aqueous phase, and then centrifuged at 3000 ~ 4000 rpm / min to remove, thereby achieving the purpose of degumming The acid value can not be higher than 0.2 mgKOH/g. Under the condition of considering the soap foot and color, the super alkali content of the refined silkworm oil is determined to be 74.4%. At this time, the hardness of the soap angle is suitable, the oil soap is easy to separate, and the acid value is And the color is up to the requirements; when the initial temperature of the oil is 45 °C; add a mass fraction of 14% potassium hydroxide aqueous solution, mix and stir for 30 ~ 40 minutes and continue to heat up until the silkworm oil temperature is controlled at 60 ~ 65 °C, The oil soap is quickly centrifuged by centrifugation at 3000 ~ 4000 rpm/min, the upper layer of grease is removed, and the mixture is stirred and washed at 120 rpm/min with distilled water at 80 ° C until the pH of the washing liquid is neutral to achieve the purpose of deacidification; Adding 4% of the quality of silkworm pupa oil to the silkworm pupa oil, silkworm pupa Temperature controlled at 40 ~ 42 ° C, stirred for 30 minutes, bleaching clay was separated by filtration to obtain refined oils pupa.

Example 4

Taking silkworm pupa powder 100g as the raw material for the extraction of silkworm pupa oil, the extraction method is as follows: In the homogenization extraction step (b) of the above examples 1-3, the silkworm pupa powder is weighed and placed 100g. In the pulverizer, petroleum ether (extraction solvent) added was replaced with ethyl acetate, and the amount to be added was the same as that of the corresponding examples, and other steps were also prepared in the same manner as in the corresponding examples to prepare refining silkworm pupa oil.

Example 5

Taking silkworm pupa powder 100g as the raw material for the extraction of silkworm pupa oil, the extraction method is as follows: In the homogenization extraction step (b) of the above Examples 1-3, 100 g of silkworm pupa powder was weighed and placed in a homogenizer, added The petroleum ether (extraction solvent) is replaced with absolute ethanol, and the amount to be added is the same as that of the corresponding examples, and other steps should be the same as in the corresponding examples to prepare refined silkworm oil.

Example 6

Taking silkworm pupa powder 100g as the raw material for the extraction of silkworm pupa oil, the extraction method is as follows: In the homogenization extraction step (b) of the above Examples 1 to 6, 100 g of silkworm pupa powder is weighed and placed in a homogenizer. The extraction solvent to be added and the amount to be added should be the same as in the corresponding examples, and the homogenizer was rotated at 1000 rpm/min, and the homogenate was collected. The other steps should be the same as in the corresponding examples to prepare refined silkworm pupa oil.

Example 7

Taking silkworm pupa powder 100g as the raw material for the extraction of silkworm pupa oil, the extraction method is as follows: In the homogenization extraction step (b) of the above Examples 1 to 6, 100 g of silkworm pupa powder is weighed and placed in a homogenizer. The extraction solvent to be added and the amount to be added should be the same as in the corresponding examples, the homogenizer was rotated at 6000 rpm/min, and the homogenate was collected. The other steps should be the same as in the corresponding examples to prepare refined silkworm cocoon oil.

In order to determine the optimum ratio and process steps of the materials used in the present invention, the inventors conducted a large number of laboratory studies, each of which was repeated three times, and the results of the experiment were the average of three replicates, and the various tests were as follows:

Material: Silkworm Cocoon: Provided by Zhejiang Zhongqi Biomedical Co., Ltd.

Reagents: Petroleum ether, glacial acetic acid and other chromatographic reagents are chromatographically pure, other reagents are of analytical grade, and all reagents are sold. Experimental equipment: Gas chromatograph, Sakamoto Shimazu production; 1 W400A high-speed universal pulverizer, Beijing Kewei Yongxing Instrument Co., Ltd.; Thermo-RC 6+ centrifuge; Shanghai medical instrument analysis factory production; Pulping machine, Shanghai Youjie Electromechanical Equipment Development Co., Ltd.; RE-2000 rotary evaporator, produced by Shanghai Yarong Biochemical Instrument Factory; GZX-9146MB: digital display blast drying oven,

Weigh 3 parts of crushed silkworm cocoon powder, 100g each, and place them in a homogenizer. Weigh 400g of extractive petroleum ether, ethyl acetate and absolute ethanol into the homogenizer to start the homogenizer. The mixture was treated with a rotation speed of 8000 rpm/min for 6 times for 5 minutes for a total of 30 minutes. The homogenate was collected, filtered with 4 to 8 layers of gauze, and the filtrate was collected and centrifuged at a speed of 4000 to 8000 rpm/min for 10 to 30 minutes. The supernatant was collected, and the supernatant was filtered under reduced pressure at -0.08 MPa in a vacuum filter to obtain a filtrate; the filtrate was reduced in a reduced pressure evaporator at 60 to 80 ° C, -0.08 MPa. The distillation solvent is recovered, the extraction solvent is recovered, and the residual extraction solvent is removed in an oven at 40 to 50 ° C to obtain silkworm pupa oil. The formula for calculating the yield of silkworm pupa oil is as follows:

The quality of silkworm cocoon powder ( _g )

The experimental and calculation results are shown in Table 1.

Table 1 Effect of different solvents on oil yield and oil quality

It can be seen from Table 1 that the oil extraction rate of ethyl acetate is the highest, but the color of the silkworm cocoon obtained is not transparent, and the odor of the cocoon oil is heavier. It indicates that the ethyl acetate is highly polar, and a non-lipid substance is proposed in addition to the oily substance. The eucalyptus oil proposed by petroleum ether is clear and transparent, and has a pale yellow color. The most volatile oleyl ether is used as an extraction solvent.

Replacement page (Article 26) 2. The effect of the mass ratio of silkworm pupa powder and extraction solvent on the yield of silkworm pupa oil

Accurately weigh 5 parts of crushed silkworm cocoon powder, each 100g, placed in the homogenizer, weigh 200g, 300g, 400g, 500g, 600g of extraction solvent, respectively, into the corresponding homogenizer, start The homogenizer was treated 6 times with a rotation speed of 8000 rpm/min for 5 minutes each time for a total of 30 minutes. The homogenate was collected, filtered with 4 to 8 layers of gauze, and the filtrate was collected and centrifuged at a speed of 4000 to 8000 rpm/min. ~30 minutes, the supernatant was collected, and the supernatant was filtered under reduced pressure at -0.08 MPa in a vacuum filter to obtain a filtrate; the filtrate was placed at 60-80 ° C in a vacuum evaporator, - 0.08MPa vacuum distillation, recovery of extraction solvent, removal of residue in an oven at 40~50 °C, extraction of soluble solution 2 The effect of the mass ratio of silkworm meal and extraction solvent on the yield of silkworm oil

It can be seen from Table 2 that as the mass ratio of silkworm pupa powder to extraction solvent increases, the yield of silkworm pupa oil also increases. When the mass ratio is greater than 1:4, the yield of silkworm pupa oil increases slowly, taking into account cost and various factors. The invention selects the mass ratio of silkworm pupa powder to extraction solvent 1: 4~6, and the best quality is 1:4.

3, the effect of the speed of the homogenizer on the yield of silkworm pupa

Weigh 6 parts of crushed silkworm cocoon powder, 100g each, placed in a homogenizer, and weigh 6 parts of petroleum ether, 400g each, and add them to the corresponding homogenizer to start homogenization. Machine speed is 8000 rpm / min 6 times, 5 minutes each time, a total of 30 minutes, collect the homogenate, filter with 4 ~ 8 layers of gauze, collect the filtrate, centrifuge with a centrifuge at 4000 ~ 8000rpm / min 10~ After 30 minutes, the supernatant was collected, and the supernatant was filtered under reduced pressure at -0.08 MPa in a vacuum filter to obtain a filtrate; the filtrate was placed at 60-80 ° C, -0.08 in a vacuum evaporator. The MPa is distilled under reduced pressure, the extraction solvent is recovered, and the residue extraction solvent is removed in an oven at 40 to 50 ° C to obtain silkworm pupa oil. By public Table 3 Effect of homogenization speed on the yield of silkworm pupa

It can be seen from Table 3 that when the homogenate rotation speed is increased from 6000 rpm/min to 8000 rpm/min, the extraction rate of silkworm pupa oil is significantly increased. When the rotation speed is increased from 8000 rpm/min to 12000 rpm/min, the extraction rate of silkworm pupa oil is not significantly increased. When the temperature is increased from 12,000 rpm/min to 16000 rpm/min, the extraction rate is decreased. This may be due to the loss of solvent due to excessive homogenization speed. Considering 8000 rpm/min as the optimum homogenization speed.

4. Effect of homogenization time on the yield of silkworm pupa

Weigh 4 parts of crushed silkworm cocoon powder, 100g each, placed in a homogenizer, and weigh 4 parts of petroleum ether, 400g each, and add them to the corresponding homogenizer to start homogenization. The machine was operated at 8000 rpm/min for 2 times, 4 times, 6 times, 8 times, 5 minutes each time, for a total of 10 minutes, 20 minutes, 30 minutes, 40 minutes, collecting the homogenate, using 4 ~ 8 layers of gauze Filtration, collecting the filtrate, centrifuging at 4000 ~ 8000 rpm for 10 ~ 30 minutes, collecting the supernatant, and filtering the supernatant in a vacuum filter at room temperature under -0.08 MPa to obtain a filtrate. The filtrate was distilled under reduced pressure at 60-80 ° C and -0.08 MPa in a vacuum evaporator to recover the extraction solvent, and the residue extraction solvent was removed in an oven at 40 to 50 ° C to obtain silkworm pupa oil. Calculate the yield of silkworm pupa oil according to formula (1). The results are shown in Table 4.

Table 4 Effect of homogenization treatment time on the yield of silkworm pupa

It can be seen from Table 4 that as the homogenization time increases, the extraction rate of silkworm pupa oil also increases. When the homogenate is treated for 30-40 minutes, the yield of silkworm pupa oil is higher, and the yield of silkworm pupa oil is 30 minutes when the homogenate is treated. highest. The treatment time of the present invention is selected to be 30 to 40 minutes, preferably 30 minutes.

5. Comparison of extraction rate and yield of silkworm pupa oil by homogenization method and solvent extraction method

In order to verify the reliability of the silkworm pupa oil extracted by the present invention, the above optimization conditions were used in the experiment. Three times of repetition, that is, the extraction solvent was petroleum ether, the mass ratio of the silkworm pupa powder to the extraction solvent was 1:4, the homogenate rotation speed was 8000 rpm/min, and the homogenization treatment time was 30 minutes. The yield of silkworm cocoon oil is calculated according to formula (1), and the extraction rate is calculated as follows: yield (%) xlOO

Swallow i: powder ® ί % ) The experimental and calculation results are shown in Table 5.

Table 5 Comparison of solvent extraction and homogenization of silkworm pupa

It can be seen from Table 5 that compared with the solvent extraction method, the yield of the silkworm pupa oil of the present invention is increased from 24.1% to 26.9%, the extraction rate is increased from 80.3% to 89.7%, and the extraction time is shortened from 2 hours to 30%. minute.

In order to verify the beneficial effects of the present invention, the silkworm pupa oil prepared by the method provided by the present invention was tested as follows:

1) Sensory test

Color: Light yellow.

Odour: Normal and no odor.

Appearance: Uniform, free of foreign matter and sediment.

2) Physical and chemical indicators of silkworm pupa oil prepared by homogenization method

Refer to GB/T 5009.37-2003 "Analytical Method for Hygienic Standards of Edible Vegetable Oils", GB/T 5534-1995 "Determination of Saponification Value of Animal and Vegetable Oils", GB/T 5530-2005 "Determination of Acid Value and Acidity of Animal and Vegetable Oils", GB/T 5532-2008 "Determination of iodine value of animal and vegetable oils", GB/T5527-1985 "Test method for determination of refractive index of vegetable oils and fats", GB5526-1985 "Measurement method of plant oils and fats", analysis of physical and chemical indicators of silkworm pupa The measurement results are shown in Table 6. Table 6 Comparison of National Standards for Silkworm Cocoon Oil and Rapeseed Oil

As can be seen from Table 6, the silkworm pupa oil prepared by the present invention is close to the quality indexes of the silkworm pupa oil standard reported in the literature.

The silkworm pupa oil prepared by the present invention was analyzed for its fatty acid composition by GC-MS.

Chromatographic conditions: VF-1701ms (30m * 0.25mm * 0.25um); Carrier gas: high purity helium; Flow rate: l.OmL / min; Inlet temperature: 250 degrees; Split ratio 20: 1; Injection volume : lul; column temperature: 80 degrees for 5 minutes, 30 degrees per minute to 200 degrees, for 1 minute, 3 degrees per minute to 230 degrees, for 10 minutes.

Mass spectrometry conditions: EI source: 70 ev; ion source temperature 250 degrees, transmission line temperature: 260 degrees; quadrupole temperature: 40 degrees; scanning range: 35-500;

The test results are shown in Table 7.

Table 7 Fatty acid composition of silkworm pupa

It can be seen from Table 7 that the relative content of unsaturated fatty acids is 75.34%. It can be seen that silkworm pupa oil contains a large amount of polyunsaturated fatty acids and has rich nutritional value.

According to the above experimental research, the present invention is compared with the existing silkworm pupa oil extraction method, the silkworm pupa oil extraction The take rate is obviously improved, the extraction time is greatly shortened, the process is simple and stable, and it is suitable for industrial production. The silkworm pupa oil product extracted by the invention has a yellow color and has the unique oil flavor of the silkworm pupa oil. Since the silkworm pupa oil has no national quality standard, compared with the edible oil such as rapeseed oil, the indicators meet the requirements.

GB1536-2004 "Rapeseed oil" quality standard, fatty acid composition analysis shows that rich in polyunsaturated fatty acids, especially α-linolenic acid rich in content, is a nutritional nutrient oil with high nutritional value.

The above description is only an embodiment of the present invention, and it should be noted that those skilled in the art can also make some improvements and retouching without departing from the core technical features of the present invention. And improvements are also within the scope of the patent protection of the present invention.

Claims

Claim

A method for extracting silkworm pupa oil, characterized in that the method comprises the following steps:

(a) pretreatment of silkworm cocoons;

(b) extraction by homogenization;

(c) preparing silkworm pupa oil;

(d) Refined silkworm cocoon oil.

The method according to claim 1, wherein the silkworm cocoon pretreatment in the step (a) is: placing the wet silkworm cocoons in a blast drying oven at 120 ° C for 12 hours and drying until the water content is less than 8%. With powder

The method according to claim 1, wherein the homogenization method in the step (b) is: placing the silkworm cocoon powder in a homogenizer, adding an extraction solvent, wherein the quality of the silkworm cocoon powder and the extraction solvent The ratio is 1: 3 ~ 6, start the homogenizer, homogenize 6 times at 6000 ~ 18000 rpm / min, 5 minutes each time, a total of 30 minutes, collect the homogenate.

The method according to claim 3, wherein the mass ratio of the silkworm meal to the extraction solvent in the step (b) is 1:4 to 6.

The method according to claim 3, wherein the mass ratio of the silkworm meal to the extraction solvent in the step (b) is 1:4.

The method according to any one of claims 3 to 5, wherein the solvent extracted in the step (b) is petroleum ether, ethyl acetate or absolute ethanol.

The method according to any one of claims 3 to 5, wherein the speed of the homogenizer in step (b) is 6000 to 8000 rpm/min.

The method according to claim 1, wherein the preparing the silkworm pupa oil in the step (c) comprises: filtering the homogenate obtained in the step (b) with 4 to 8 layers of gauze, collecting the filtrate, at 4000 ~ Centrifuge at 8000 rpm/min for 10 to 30 minutes, collect the supernatant, and filter the supernatant in a vacuum filter at room temperature under -0.08 MPa under reduced pressure. The filtrate is placed in a vacuum evaporator at 60 ~ 80 ° C, -0.08 MPa under reduced pressure distillation, the extraction solvent was recovered, and the residue extraction solvent was removed in an oven at 40 to 50 ° C to obtain silkworm pupa oil.

The method according to claim 1, wherein the refining the cocoon oil in the step (d) comprises:

2) Deacidification of silkworm oil;

3) Refining of silkworm cocoon oil.

10. The method of claim 9 wherein:

The degumming of the silkworm pupa oil in the step 1) is: heating the silkworm pupa oil obtained in the step (c) to 70 ° C, and adding the citric acid crystal C ₆ H ₈ 0 ₇ H ₂ 0 which accounts for 0.05% to 0.12% of the silkworm pupa oil quality, After mixing, let stand for 5-6 minutes, and then centrifuge at 3000~4000rpm/min to achieve the purpose of degumming;

The deacidification of the silkworm pupa oil in the step 2) is: the acid value can not be higher than 0.2 mg KOH / g as the standard, in the case of comprehensive consideration of soap feet and color, the determination of the super alkali amount of the refining silkworm pupa oil is 74.4%, when the hair When the initial temperature of the oil is 45 °C; add a potassium hydroxide aqueous solution with a mass fraction of 14%, mix and stir for 30~40 minutes and continue to heat up until the temperature of the silkworm cocoon is controlled at 60 ~ 65 °C, and pass 3000 ~ 4000rpm/min quickly. The oil soap is separated by centrifugation, the upper layer of oil is removed, and the mixture is washed with 120 ° C distilled water at 120 rpm/min until the pH of the washing liquid is neutral, thereby achieving the purpose of deacidification;

The refining of the silkworm pupa oil in the step 2) is: adding the decolorized white clay which accounts for 4% of the silkworm pupa oil in the silkworm pupa oil after deacidification, the temperature of the silkworm pupa oil is controlled at 40 to 42 ° C, stirring for 30 minutes, and separating the decolorized white clay by filtration, Refined silkworm cocoon oil.