CN111500360A

CN111500360A - Antioxidant sesame oil and preparation method thereof

Info

Publication number: CN111500360A
Application number: CN202010437366.0A
Authority: CN
Inventors: 崔艳兰
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-05-21
Filing date: 2020-05-21
Publication date: 2020-08-07

Abstract

The invention provides an antioxidant sesame oil and a preparation method thereof, wherein sesame is poured into immersion oil for ultrasonic immersion treatment, filtration, crushing, spreading and evenly spraying the immersion oil, standing for immersion, squeezing to obtain crude oil, then adding a catalyst into the crude oil, stirring for reaction, and post-treatment to obtain the antioxidant sesame oil, and the antioxidant property of the obtained sesame oil can be improved without adding an additional synthetic antioxidant. In the oil preparation process, on one hand, the loss of tocopherol substances and sesamin is avoided, on the other hand, the sesamolin is promoted to be converted into sesaminol, sesamolin phenol and sesamol, and according to research, the sesaminol and vitamin E have a synergistic effect and the oxidation resistance is enhanced.

Description

Antioxidant sesame oil and preparation method thereof

Technical Field

The invention relates to the technical field of food processing, in particular to antioxidant sesame oil and a preparation method thereof.

Background

Sesame oil is extracted from sesame, has special fragrance, is an essential good seasoning in daily diet of people, and can be used for cold dishes, hot dishes and soup. The sesame oil is rich in vitamin E, carotene, saturated and unsaturated fatty acids, phospholipid, sterol, stigmasterol, campesterol, cycloartenol, squalene, etc. In the fatty acid of the sesame oil, the unsaturated fatty acid accounts for about 84 percent, and the digestibility can reach 98 percent. Sesame oil has many benefits to human health, such as: delaying aging, protecting blood vessel, loosening bowel to relieve constipation, relieving tobacco and wine poisoning, protecting throat, treating rhinitis, resolving macula, moistening skin, etc.

The main methods for preparing sesame oil from sesame seeds comprise a water substitution method, a leaching method and a hot pressing method, but the water substitution method has the disadvantages of high labor intensity, low oil yield and small production scale; crude oil obtained by a leaching method needs to be refined, and nutrient components and antioxidant components of oil are easy to lose in the refining process; although the sesame oil obtained by the hot pressing method has a strong fragrance, substances harmful to human health, such as aldehyde ketone compounds, benzopyrene, pigments and the like, are generated, and in the high-temperature pressing process, proteins in the sesame are denatured and inactivated, so that the nutritional value is greatly reduced.

In addition to these three general methods, a low-temperature squeezing process which has been recently developed is more and more favored, which reduces loss of protein and nutrients in sesame, but still has problems of low oil yield, non-sterilization, poor oxidation stability of fats and oils, and short shelf life. Although sesame contains a large amount of unsaturated fatty acids which are easily oxidized, the sesame oil is theoretically not easy to preserve, but in fact pure sesame oil can be preserved for a relatively long time compared to other edible oils because sesame and sesame oil contain a certain amount of antioxidant substances. The antioxidant substances mainly comprise lignan compounds and tocopherol substances, wherein the lignan compounds comprise sesamin (a fat-soluble phenol organic substance) and sesamolin, and the sesamol are converted from the sesamolin in the oil preparation process. Unfortunately, these natural antioxidants tend to be more lost during the oil manufacturing process, and in order to improve the antioxidant properties of the product, one has to add additional antioxidants. The existing commonly used artificially synthesized antioxidant has accumulated toxicity and is not beneficial to human health, so that how to improve the oxidation resistance of the sesame oil on the premise of not using the artificially synthesized antioxidant is particularly important.

Disclosure of Invention

The invention aims to provide antioxidant sesame oil and a preparation method thereof, and aims to solve the technical problem that the improvement of the antioxidant property of the sesame oil depends on artificially synthesizing an antioxidant.

In order to realize the purpose, the invention provides a preparation method of antioxidant sesame oil, which comprises the following specific steps:

(1) preparation of immersion oil: respectively crushing hawthorn seeds and quinoa and mixing the crushed hawthorn seeds and quinoa into mixed powder, then adding the mixed powder into petroleum ether, carrying out ultrasonic extraction, filtering, taking filtrate, and removing the petroleum ether to obtain the immersion oil;

(2) preparation of the catalyst: firstly, tetraethyl titanate is mixed with absolute ethyl alcohol, glacial acetic acid and deionized water, stirred and hydrolyzed, an ethanol solution of zinc acetate is slowly dripped, ultrasonic oscillation is carried out uniformly, the ethanol is removed, and freeze drying is carried out, thus obtaining the catalyst;

(3) then, pouring sesame into the immersion oil obtained in the step (1) for ultrasonic immersion treatment, filtering, crushing, spreading, uniformly spraying the immersion oil, standing for immersion, and squeezing to obtain crude oil;

(4) and (3) finally, transferring the crude oil into a reaction kettle, adding the catalyst obtained in the step (2), stirring for reaction, performing post-treatment, and filling to obtain the antioxidant sesame oil.

Preferably, in the step (1), the mass ratio of the hawthorn seeds to the quinoa is 1: 0.1 to 0.2.

Preferably, in the step (1), the particle size of the mixed powder is 200-300 meshes.

Preferably, in the step (1), the mass-to-volume ratio of the mixed powder to the petroleum ether is 1 mg: 8-10 m L.

Preferably, in the step (1), the process conditions of the ultrasonic extraction are as follows: extracting with 400-600W ultrasonic wave for 60-80 minutes.

Preferably, in step (1), the petroleum ether is removed by rotary evaporation.

Preferably, in the step (2), the mass ratio of the tetraethyl titanate to the ethanol solution of anhydrous ethanol, glacial acetic acid, deionized water and zinc acetate is 1: 10-15: 2-4: 5-8: 2-3, adding zinc acetate into absolute ethyl alcohol with the weight being 8-10 times that of the zinc acetate, and uniformly oscillating by ultrasonic waves.

Preferably, in the step (2), the process conditions of the ultrasonic oscillation are as follows: ultrasonic oscillation at 300-500W for 40-60 minutes.

Preferably, in the step (2), ethanol is removed by a rotary evaporation method, and the freeze drying process conditions are as follows: freezing at-40 to-50 ℃ for 6 to 8 hours, vacuumizing to 0.2 to 0.3Pa, heating to 20 to 30 ℃, and keeping the vacuum degree for 6 to 9 hours.

Preferably, in the step (3), the sesame is plump in shape, and is subjected to screening, stone removal and dust removal treatment, and is crushed and sieved by a sieve of 60-80 meshes.

Preferably, in the step (3), the ultrasonic dipping treatment time is 2-3 hours, and the standing dipping time is 80-100 minutes; the dosage of the dipping oil in the ultrasonic dipping treatment and the standing dipping is 5-8 times and 0.1-0.2 time of the weight of the sesame respectively, and the ultrasonic dipping treatment is realized by adopting 300-500W ultrasonic oscillation.

Preferably, in the step (3), the pressing process conditions are as follows: squeezing for 50-80 minutes under the conditions of 40-50 MPa and 50-60 ℃.

Preferably, in the step (4), the amount of the catalyst is 0.3-0.4% of the weight of the crude oil.

Preferably, in the step (4), the process conditions of the stirring reaction are as follows: stirring and reacting for 40-60 minutes at the stirring speed of 1000-1200 rpm under the condition of 70-80 ℃.

Preferably, in the step (4), the post-treatment is performed by the following specific method: centrifuging at 6000-8000 rpm for 5-8 minutes, performing suction filtration, washing with deionized water for 2-3 times, and performing vacuum drying at 50-55 ℃ for 5-8 hours.

The antioxidant sesame oil is obtained by the preparation method.

The invention has the following beneficial effects:

the invention firstly pours sesame into immersion oil for ultrasonic immersion treatment, filters, crushes, spreads evenly sprays immersion oil, stands for immersion, squeezes to obtain crude oil, then adds catalyst into the crude oil, stirs for reaction, and carries out post treatment to obtain the antioxidant sesame oil, and the antioxidant property of the obtained sesame oil can be improved without adding artificial synthetic antioxidant additionally. In the oil preparation process, on one hand, the loss of tocopherol substances and sesamin is avoided, on the other hand, the sesamolin is promoted to be converted into sesaminol, sesamolin phenol and sesamol, and according to research, the sesaminol and vitamin E have a synergistic effect and the oxidation resistance is enhanced.

The specific analysis is as follows:

the immersion oil is prepared by taking hawthorn seeds and quinoa as raw materials and carrying out ultrasonic extraction on petroleum ether, wherein the hawthorn seeds contain rich polyphenol compounds, particularly including phenolic acid, flavonoid and the like, which are excellent hydrogen proton or electron donors and can form stable phenol free radical intermediates, so that peroxides or other free radicals are changed into stable hydroperoxides, and the occurrence of chain reaction, namely a chain blocking providing agent, is prevented. And because of the resonance delocalization effect and no position suitable for molecular oxygen attack, the material can not initiate new free radicals or be quickly oxidized due to chain reaction, and is relatively stable. It shows excellent antioxidant activity due to its high reactivity of hydrogen substitution and its ability to phagocytose free radicals. Quinoa is a plant food containing high-quality complete protein, contains rich amino acids, and because amino groups, carboxylic acids and the like in the amino acids can form hydrogen bond action with phenolic hydroxyl groups in polyphenols, the hydrogen supply capacity of the phenolic hydroxyl groups is further enhanced under the action of the hydrogen bond action, so that the antioxidation effect is enhanced, namely, the hawthorn seeds and the quinoa have synergistic effect, and the antioxidation effect of the immersion oil is enhanced.

Before the sesame is crushed, the sesame is subjected to ultrasonic dipping treatment by using dipping oil, so that a layer of oil film with a good antioxidant effect is formed on the surface of the sesame, a protection and dissolution effect is achieved, and nutrient substances released along with the crushing of the sesame are dissolved in the oil film and adhered to the surface of the oil film, so that the loss of nutrient components of the sesame in the crushing process is avoided. After the crushing is finished, spreading the crushed sesame seeds to be thin and uniformly spraying the immersion oil, so that the exposed surfaces formed after the crushing are covered with a layer of oil film again, and the immersion oil has good antioxidation effect, so that the sesame seeds can be effectively protected, and loss and oxidative deterioration are avoided. The ultrasonic impregnation treatment and the standing impregnation supplement each other, and the nutrient components in the sesame are protected in an all-round way.

The crude oil obtained after squeezing is stirred and reacted by a catalyst, the catalyst is prepared by taking ethanol solution of tetraethyl titanate and zinc acetate as raw materials, the tetraethyl titanate is hydrolyzed and is compounded with the zinc acetate, and the obtained catalyst has good water solubility (is convenient to remove after treatment) and contains titanium and zinc. The sesamolin in the sesame firstly obtains hydrogen ions, and then the sesamolin is subjected to intramolecular rearrangement (electron shift) or thermal decomposition to be converted into sesaminol and sesamol, and a large amount of sesaminol and sesamol is generated to be beneficial to improving the oxidation resistance of the sesame oil. Titanium in the catalyst has good electron-withdrawing ability and promotes the formation of hydrogen ions in a system, zinc has larger electronegativity and can promote electron displacement and realize intramolecular rearrangement, and the titanium and the zinc are matched with each other to complete the conversion of sesamolin to sesamol and synergistically improve the oxidation resistance of the sesame oil. In addition, phenolic acid, amino acid and the like in the immersion oil can also form hydrogen bond action with an intermediate of sesamolin hydrogen ions to promote the displacement of electrons, further promote the completion of the conversion reaction and be beneficial to improving the oxidation resistance of the sesame oil. In a word, the invention greatly improves the content of sesaminol and sesamol in sesame oil, avoids the loss of vitamin E in sesame, and leads the sesaminol and the vitamin E to synergistically improve the oxidation resistance of the product.

One of the raw materials of the catalyst, tetraethyl titanate, has a certain toxic action, so the invention should reduce the material proportion of tetraethyl titanate when preparing the catalyst, and lead the tetraethyl titanate to be completely hydrolyzed to generate titanium oxide and be compounded (the catalyst has less dosage and is harmless to human bodies) so as to avoid transferring to sesame oil products during catalytic reaction and damaging human health.

In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below.

Detailed Description

The following is a detailed description of embodiments of the invention, but the invention can be implemented in many different ways, as defined and covered by the claims.

Example 1:

a preparation method of antioxidant sesame oil comprises the following specific steps:

In the step (1), the mass ratio of the hawthorn seeds to the quinoa is 1: 0.1.

in the step (1), the particle size of the mixed powder is 300 meshes.

In the step (1), the mass-to-volume ratio of the mixed powder to the petroleum ether is 1 mg: 8m L.

In the step (1), the process conditions of ultrasonic extraction are as follows: ultrasonic extraction at 600W for 60 min.

In the step (1), petroleum ether is removed by a rotary evaporation method.

In the step (2), the mass ratio of the tetraethyl titanate to the ethanol solution of the absolute ethyl alcohol, the glacial acetic acid, the deionized water and the zinc acetate is 1: 15: 2: 8: 2, the ethanol solution of the zinc acetate is obtained by adding the zinc acetate into 10 times of absolute ethanol by weight and uniformly oscillating by ultrasonic waves.

In the step (2), the process conditions of ultrasonic oscillation are as follows: the ultrasonic wave was oscillated at 300W for 60 minutes.

In the step (2), ethanol is removed by a rotary evaporation method, and the freeze drying process conditions are as follows: freezing at-40 deg.C for 8 hr, vacuumizing to 0.2Pa, heating to 30 deg.C, and maintaining vacuum degree for 6 hr.

In the step (3), the sesame is plump in shape, and is subjected to screening, stone removal and dust removal treatment, and is crushed and sieved by a 80-mesh sieve.

In the step (3), the ultrasonic dipping time is 2 hours, and the standing dipping time is 100 minutes; the dosage of the soaking oil in the ultrasonic soaking treatment and standing soaking is 5 times and 0.2 time of the weight of sesame respectively, and the ultrasonic soaking treatment is realized by adopting 300W ultrasonic oscillation.

In the step (3), the squeezing process conditions are as follows: squeezing under 50MPa and 50 deg.C for 80 min.

In the step (4), the amount of the catalyst is 0.3 percent of the weight of the crude oil.

In the step (4), the technological conditions of the stirring reaction are as follows: the reaction was stirred at a stirring rate of 1000 rpm for 60 minutes at 80 ℃.

In the step (4), the post-treatment method comprises the following specific steps: centrifuging at 6000 rpm for 8 minutes, filtering, washing with deionized water for 2 times, and vacuum drying at 55 deg.C for 5 hours.

The antioxidant sesame oil is obtained by the preparation method.

Example 2:

In the step (1), the mass ratio of the hawthorn seeds to the quinoa is 1: 0.2.

in the step (1), the particle size of the mixed powder is 200 meshes.

In the step (1), the mass-to-volume ratio of the mixed powder to the petroleum ether is 1 mg: 10m L.

In the step (1), the process conditions of ultrasonic extraction are as follows: ultrasonic extraction at 400W for 80 minutes.

In the step (1), petroleum ether is removed by a rotary evaporation method.

In the step (2), the mass ratio of the tetraethyl titanate to the ethanol solution of the absolute ethyl alcohol, the glacial acetic acid, the deionized water and the zinc acetate is 1: 10: 4: 5: and 3, adding zinc acetate into absolute ethyl alcohol with the weight 8 times that of the zinc acetate in the ethanol solution of the zinc acetate, and uniformly oscillating by ultrasonic waves.

In the step (2), the process conditions of ultrasonic oscillation are as follows: 500W ultrasonic oscillation was carried out for 40 minutes.

In the step (2), ethanol is removed by a rotary evaporation method, and the freeze drying process conditions are as follows: freezing at-50 deg.C for 6 hr, vacuumizing to 0.3Pa, heating to 20 deg.C, and maintaining vacuum degree for 9 hr.

In the step (3), the sesame is plump in shape, and is subjected to screening, stone removal and dust removal treatment, and is crushed and sieved by a 60-mesh sieve.

In the step (3), the ultrasonic dipping treatment time is 3 hours, and the standing dipping time is 80 minutes; the dosage of the immersion oil in the ultrasonic immersion treatment and the standing immersion is respectively 8 times and 0.1 time of the weight of the sesame, and the ultrasonic immersion treatment is realized by adopting 500W ultrasonic oscillation.

In the step (3), the squeezing process conditions are as follows: squeezing under 40MPa at 60 deg.C for 50 min.

In the step (4), the amount of the catalyst is 0.4% of the weight of the crude oil.

In the step (4), the technological conditions of the stirring reaction are as follows: the reaction was stirred at a stirring rate of 1200 rpm for 40 minutes at 70 ℃.

In the step (4), the post-treatment method comprises the following specific steps: centrifuging at 8000 rpm for 5 min, vacuum filtering, washing with deionized water for 3 times, and vacuum drying at 50 deg.C for 8 hr.

The antioxidant sesame oil is obtained by the preparation method.

Example 3:

In the step (1), the mass ratio of the hawthorn seeds to the quinoa is 1: 0.15.

in the step (1), the particle size of the mixed powder is 300 meshes.

In the step (1), the mass-to-volume ratio of the mixed powder to the petroleum ether is 1 mg: 9m L.

In the step (1), the process conditions of ultrasonic extraction are as follows: the ultrasonic extraction was carried out at 500W for 70 minutes.

In the step (1), petroleum ether is removed by a rotary evaporation method.

In the step (2), the mass ratio of the tetraethyl titanate to the ethanol solution of the absolute ethyl alcohol, the glacial acetic acid, the deionized water and the zinc acetate is 1: 12: 3: 6: 2.5, adding zinc acetate into 9 times of absolute ethyl alcohol by weight, and uniformly oscillating by ultrasonic waves to obtain the zinc acetate ethanol solution.

In the step (2), the process conditions of ultrasonic oscillation are as follows: the ultrasonic wave of 400W was oscillated for 50 minutes.

In the step (2), ethanol is removed by a rotary evaporation method, and the freeze drying process conditions are as follows: freezing at-45 deg.C for 7 hr, vacuumizing to 0.2Pa, heating to 25 deg.C, and maintaining vacuum degree for 8 hr.

In the step (3), the sesame is plump in shape, and is subjected to screening, stone removal and dust removal treatment, and is crushed and sieved by a 70-mesh sieve.

In the step (3), the ultrasonic dipping time is 2.5 hours, and the standing dipping time is 90 minutes; the dosage of the immersion oil in the ultrasonic immersion treatment and the standing immersion is 6 times and 0.15 time of the weight of sesame respectively, and the ultrasonic immersion treatment is realized by adopting 400W ultrasonic oscillation.

In the step (3), the squeezing process conditions are as follows: squeezing under 45MPa and 55 deg.C for 70 min.

In the step (4), the amount of the catalyst is 0.35% of the weight of the crude oil.

In the step (4), the technological conditions of the stirring reaction are as follows: the reaction was stirred at a stirring rate of 1100 rpm for 50 minutes at 75 ℃.

In the step (4), the post-treatment method comprises the following specific steps: centrifuging at 7000 rpm for 6 min, filtering, washing with deionized water for 3 times, and vacuum drying at 52 deg.C for 6 hr.

The antioxidant sesame oil is obtained by the preparation method.

Comparative example 1

The hawthorn seeds are omitted when preparing the immersion oil.

The rest is the same as example 1.

Comparative example 2

Quinoa was omitted when the immersion oil was prepared.

The rest is the same as example 1.

Comparative example 3

The ethanolic solution of zinc acetate was omitted from the preparation of the catalyst.

The rest is the same as example 1.

Comparative example 4

The ultrasonic immersion treatment is omitted in step (3).

The rest is the same as example 1.

Comparative example 5

In the step (3), the dipping oil is not sprayed, and then the mixture is kept stand for dipping.

The rest is the same as example 1.

Test examples

The oxidation induction time of the sesame oil obtained in examples 1 to 3 and comparative examples 1 to 5 was measured by means of a 743-type Rancimat oil oxidation rancidity apparatus, and a certain brand of commercially available sesame oil was used as a control group, and the measurement temperature was 120 ℃ and the air flow rate was 10L/h.

Peroxide number determinations are made with reference to GB/T8233-2018 and GB/T5538-2005.

The results are shown in Table 1.

TABLE 1 Oxidation resistance comparison

	Oxidative induction time (h)	Peroxide number (mmol/kg)
			Control group	5.5	5.3
Example 1	25.8	0.08
			Example 2	25.5	0.09
Example 3	26.0	0.06
			Comparative example 1	8.9	3.35
Comparative example 2	10.2	2.73
			Comparative example 3	17.8	1.23
Comparative example 4	10.5	2.69
			Comparative example 5	11.7	2.37

As shown in Table 1, the sesame oil obtained in examples 1 to 3 had a long oxidation induction time, a low peroxide number, and a significantly high oxidation resistance.

Compared example 1, hawthorn seeds are omitted when the immersion oil is prepared, and compared example 2, quinoa is omitted when the immersion oil is prepared, so that nutritional ingredients are lost or deteriorated in the sesame squeezing process, and the oxidation resistance of sesame oil is obviously deteriorated; comparative example 3 the ethanol solution of zinc acetate is omitted when the catalyst is prepared, the catalytic effect of the catalyst is obviously deteriorated, the conversion of sesamolin is not sufficient, and the oxidation resistance of sesame oil is deteriorated; comparative example 4 ultrasonic impregnation treatment was omitted in step (3), and comparative example 5 standing impregnation was omitted after spraying impregnation oil in step (3), resulting in insufficient protection of nutrients of sesame and significant deterioration of oxidation resistance of sesame oil.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The preparation method of the antioxidant sesame oil is characterized by comprising the following specific steps:

2. The preparation method according to claim 1, wherein in the step (1), the mass ratio of the hawthorn seeds to the quinoa is 1: 0.1 to 0.2.

3. The preparation method according to claim 1, wherein in the step (1), the mass-to-volume ratio of the mixed powder to the petroleum ether is 1 mg: 8-10 m L.

4. The preparation method according to claim 1, wherein in the step (1), the process conditions of the ultrasonic extraction are as follows: extracting with 400-600W ultrasonic wave for 60-80 minutes.

5. The preparation method according to claim 1, wherein in the step (2), the mass ratio of the tetraethyl titanate to the ethanol solution of anhydrous ethanol, glacial acetic acid, deionized water and zinc acetate is 1: 10-15: 2-4: 5-8: 2-3, adding zinc acetate into absolute ethyl alcohol with the weight being 8-10 times that of the zinc acetate, and uniformly oscillating by ultrasonic waves.

6. The preparation method according to claim 1, wherein in the step (2), the process conditions of the ultrasonic oscillation are as follows: ultrasonic oscillation at 300-500W for 40-60 minutes.

7. The preparation method according to claim 1, wherein in the step (3), the ultrasonic immersion treatment is carried out for 2 to 3 hours, and the standing immersion is carried out for 80 to 100 minutes; the dosage of the dipping oil in the ultrasonic dipping treatment and the standing dipping is 5-8 times and 0.1-0.2 time of the weight of the sesame respectively, and the ultrasonic dipping treatment is realized by adopting 300-500W ultrasonic oscillation.

8. The preparation method according to claim 1, wherein in the step (3), the pressing process conditions are as follows: squeezing for 50-80 minutes under the conditions of 40-50 MPa and 50-60 ℃.

9. The preparation method according to claim 1, wherein in the step (4), the process conditions of the stirring reaction are as follows: stirring and reacting for 40-60 minutes at the stirring speed of 1000-1200 rpm under the condition of 70-80 ℃.

10. An antioxidant sesame oil prepared by any one of claims 1 to 9.