Preparation method of cooking and stir-frying vegetable oil

Abstract

The invention belongs to the technical field of edible oil processing, and provides a preparation method of cooking and stir-frying vegetable oil, which comprises the following steps: preparing plant seeds and fruits, cleaning and drying, selecting different modes for crushing, adding distilled water, putting into an ultrasonic reactor for pretreatment, and then carrying out step-by-step enzymolysis and enzyme deactivation under certain conditions, thereby obtaining the cooking and stir-frying vegetable oil. The preparation method comprises the following steps: carrying out first-time centrifugal treatment to obtain free oil I and emulsion, carrying out demulsification treatment on the emulsion through ultrasonic waves and microwaves in sequence, carrying out centrifugal operation to obtain free oil II, and mixing the free oil I with the free oil II to obtain the final vegetable oil, by accelerating the heat transfer and mass transfer process, the overall extraction time can be shortened, the subsequent extraction engineering operation is more convenient, the extraction rate of the vegetable oil is improved, the oil is pretreated through ultrasonic waves, the emulsion is demulsified in a mode of combining ultrasonic waves and microwaves, the demulsification rate can be effectively improved, and the extraction rate of the vegetable oil is further improved.

Description

Technical Field

[0001] The invention belongs to the technical field of edible oil processing, in particular to a method for preparing cooking and frying vegetable oil. Background Art

[0002] Vegetable oil is a compound composed of unsaturated fatty acids and glycerol. It is an oil obtained from the fruits, seeds, and germs of plants. Vegetable oil is made from oil-rich plant kernels. After a series of pretreatments, it is extracted by mechanical pressing or solvent extraction to obtain crude oil, which is then refined.

[0003] In addition, most of the vegetable oils on the market, including leaching and pressing types, need to go through the refining process and semi-refining high-temperature treatment process. The refining process requires the crude oil to be degummed, alkali-refined, decolorized, deodorized and other processes. Most of the processes will have exogenous substances added, which will also affect food safety and the content and availability of nutrients. The deodorization process of the semi-refining process also requires the crude oil to be treated at high temperature and high pressure. High-temperature heating may even cause the oil to produce harmful substances such as trans fatty acids and oil polymers. At the same time, high temperature will increase the solubility of plant wax (hydrocarbon substances) in edible oil, resulting in unclean filtration and dewaxing during the semi-refining process. This type of plant wax will undergo chemical deterioration and produce harmful substances when heated at high temperature during consumption. At the same time, under low temperature conditions, plant wax will precipitate, especially in the north. The precipitated plant wax will condense into flocculent crystals in sunflower oil and soybean oil, affecting the overall appearance of the oil and being unfavorable for sales.

[0004] The aqueous enzymatic oil production method is safe, green, mild in preparation conditions, and low in energy consumption. The aqueous enzymatic method is used to produce vegetable oil. This method mainly extracts oil from oilseeds effectively through enzymatic hydrolysis, and recovers by-products such as saponins and carbohydrate active substances. These by-products can be further utilized as green feed additives or saponin crude products. However, when using traditional aqueous enzymatic oil production technology to pretreat plant raw materials, the oil extraction process in plants is relatively complicated and the extraction time is long, thereby reducing the extraction efficiency.

[0005] Therefore, those skilled in the art have proposed a method for preparing cooking and frying vegetable oil to solve the problems raised in the background art. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a method for preparing cooking and stir-frying vegetable oil, so as to solve the problems that when the traditional water-enzymatic oil-making technology in the prior art pretreats the plant raw materials, the oil extraction process in the plant is relatively complicated, the extraction time is long, and the extraction efficiency is low.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for preparing cooking and frying vegetable oil comprises the following steps:

[0009] S1: Prepare plump and undamaged plant seeds and fruits, wash them with clean water, and then dry them for later use;

[0010] S2: The dried plant seeds and fruits are ground by wet method or dry method according to the moisture content of the different plant seeds and fruits to obtain ground oil;

[0011] S3: Take the crushed oil, add a certain volume of distilled water, and place it in an ultrasonic reactor for pretreatment, and the ultrasonic time is 20-60 minutes;

[0012] S4: performing step-by-step enzymatic hydrolysis: (1) adding complex polysaccharide enzyme for hydrolysis, the hydrolysis temperature is 40-60°C, the pH is 4-5, and the time is 40-60 min; (2) alkaline extraction, the alkaline extraction parameters are pH 8-9, temperature 50-60°C, and time 30-40 min; (3) adding protease for hydrolysis, the hydrolysis temperature is 40-60°C, pH 8-9, and time is 2-3 h, to obtain an enzymatic mixed solution;

[0013] S5: heating the enzymatic mixed solution to 80-90°C and maintaining it for 10 minutes to inactivate the enzyme;

[0014] S6: Then centrifuge at a speed of 4000-4500 r / min for 10-15 min to collect free oil and emulsion;

[0015] S7: adding deionized water to the emulsion, mixing, placing in an ultrasonic cell pulverizer, treating at a certain ultrasonic temperature and ultrasonic intensity for a certain time, taking out, then adjusting the pH of the pretreated emulsion, placing it in a microwave oven, treating at a certain microwave intensity for a certain time, and then centrifuging at a centrifugal speed of 4000-4500 r / min for 10-15 min to obtain free oil II, a water phase mixture and residue;

[0016] S8: Mix the free oil 1 and the free oil 2 to obtain the final vegetable oil.

[0017] Preferably, in the step S2, the plant seeds and fruits are crushed and ground to 80-150 mesh.

[0018] Preferably, the ratio of oil to distilled water in step S3 is 1:6.

[0019] Preferably, the ultrasonic parameters of the ultrasonic reactor in step S3 include ultrasonic temperature and ultrasonic intensity, the ultrasonic temperature is 40-45°C, and the ultrasonic intensity is 300-400W.

[0020] Preferably, in step S4, the complex polysaccharide enzyme in the stepwise enzymatic hydrolysis step (1) includes pectinase, β-glucanase and cellulase, and the volume ratio of the three is 2:1:1, and the enzyme addition amount is 1.0%.

[0021] Preferably, in the step S4, the amount of protease added in the stepwise enzymatic hydrolysis step (3) is 1.5%.

[0022] Preferably, in step S7, the emulsion is treated at an ultrasonic temperature of 40-60° C. and an ultrasonic intensity of 350-500 W for 30-50 s.

[0023] Preferably, in step S7, after ultrasonic pretreatment, the pH value of the emulsion is adjusted to 4.5-5.5.

[0024] Preferably, in the step S7, after adjusting the pH value, the mixture is treated at a microwave intensity of 600-700 W for 70-100 s.

[0025] Preferably, the plant seeds and fruits in step S1 include camellia, oil palm, okra and perilla.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The invention pre-treats the oil under ultrasonic conditions, and the ultrasound can strengthen the extraction of oil in the plant, accelerate the heat transfer and mass transfer process, reduce the overall extraction time, make the subsequent extraction engineering operation more convenient, and improve the vegetable oil extraction rate; in the enzymatic hydrolysis process, firstly, a composite polysaccharide enzyme (pectinase, beta-glucanase and cellulase) is used to perform the first enzymatic hydrolysis under certain conditions, and then alkali extraction is performed, and then a protease is used to perform the second enzymatic hydrolysis under certain conditions to obtain an enzymatic hydrolysis mixed solution, and the enzymatic hydrolysis efficiency is improved through the step-by-step enzymatic hydrolysis, and the vegetable oil extraction rate is further improved; finally, in the demulsification process, the emulsion is demulsified by combining ultrasound with microwaves, so that the demulsification rate can be effectively improved, and the vegetable oil extraction rate can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 The present invention is a schematic flow chart of a method for preparing vegetable oil for cooking and stir-frying. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] As attached Figure 1 As shown:

[0032] Embodiment 1:

[0033] The present invention provides a method for preparing cooking and frying vegetable oil, comprising the following steps:

[0034] S1: Prepare plump and undamaged plant seeds and fruits, wash them with clean water, and then dry them for later use;

[0035] Specifically, the plant seeds and fruits in step S1 include camellia, oil palm, okra and perilla.

[0036] S2: The dried plant seeds and fruits are ground by wet method or dry method according to the moisture content of the different plant seeds and fruits to obtain ground oil;

[0037] Specifically, in step S2, the plant seeds and fruits are crushed and ground into 80-150 meshes.

[0038] S3: Take the crushed oil, add a certain volume of distilled water, and place it in an ultrasonic reactor for pretreatment, and the ultrasonic time is 30 minutes;

[0039] Specifically, the ratio of oil to distilled water in step S3 is 1:6.

[0040] Specifically, the ultrasonic parameters of the ultrasonic reactor in step S3 include ultrasonic temperature and ultrasonic intensity. The ultrasonic temperature is 45° C. and the ultrasonic intensity is 350W.

[0041] S4: performing step-by-step enzymatic hydrolysis: (1) adding complex polysaccharide enzyme for hydrolysis at a temperature of 40°C, a pH of 4, and a time of 40 min; (2) alkaline extraction at a pH of 8, a temperature of 50°C, and a time of 30 min; (3) adding protease for hydrolysis at a temperature of 40°C, a pH of 8, and a time of 2 h to obtain an enzymatic mixed solution;

[0042] Specifically, in step S4, the complex polysaccharide enzyme in the stepwise enzymatic hydrolysis step (1) includes pectinase, β-glucanase and cellulase, and the volume ratio of the three is 2:1:1, and the enzyme addition amount is 1.0%.

[0043] Specifically, in the step S4, the amount of protease added in the stepwise enzymatic hydrolysis step (3) is 1.5%.

[0044] S5: heating the enzymatic mixed solution to 80°C and maintaining it for 10 minutes to inactivate the enzyme;

[0045] S6: Then centrifuge at a speed of 4000 r / min for 10 min to collect free oil and emulsion;

[0046] S7: adding deionized water to the emulsion, mixing, placing in an ultrasonic cell pulverizer, treating at a certain ultrasonic temperature and ultrasonic intensity for a certain time, taking out, then adjusting the pH of the pretreated emulsion, placing it in a microwave oven, treating at a certain microwave intensity for a certain time, and then centrifuging at a centrifugal speed of 4000 / min for 10 minutes to obtain free oil II, a water phase mixture and a residue;

[0047] Specifically, in step S7, the emulsion is treated at an ultrasonic temperature of 40° C. and an ultrasonic intensity of 350 W for 30 seconds.

[0048] Specifically, in step S7, after the ultrasonic pretreatment, the pH value of the emulsion is adjusted to 4.5.

[0049] Specifically, in the step S7, after adjusting the pH value, the mixture is treated at a microwave intensity of 600 W for 70 seconds.

[0050] S8: Mix the free oil 1 and the free oil 2 to obtain the final vegetable oil.

[0051] Further, free oil 1 and free oil 2 are combined and weighed to calculate the extraction rate of vegetable oil; extraction rate of vegetable oil = (mass of free oil 1 + mass of free oil 2) / mass of fat in plant × 100%

[0052] From the above, it can be seen that by crushing the oil and distilled water at an oil ratio of 1:6, the mixture of oil and water is pretreated under the conditions of ultrasonic temperature of 45°C, ultrasonic intensity of 350W, and ultrasonic time of 30min to strengthen the extraction of oils in plants and accelerate the heat and mass transfer process, which can reduce the overall extraction time, make subsequent extraction engineering operations more convenient, and improve the extraction rate.

[0053] Embodiment 2:

[0054] This embodiment is basically the same as the previous embodiment, except that different extraction conditions are adopted in the step-by-step enzymatic hydrolysis step. The ultrasonic temperature in step S3 is 45°C, the ultrasonic intensity is 350W, and the ultrasonic time is 30min, which are fixed conditions in this embodiment.

[0055] The present invention provides a method for preparing cooking and frying vegetable oil, comprising the following steps:

[0056] S1: Prepare plump and undamaged plant seeds and fruits, wash them with clean water, and then dry them for later use;

[0057] Specifically, the plant seeds and fruits in step S1 include camellia, oil palm, okra and perilla.

[0058] S2: The dried plant seeds and fruits are ground by wet method or dry method according to the moisture content of the different plant seeds and fruits to obtain ground oil;

[0059] Specifically, in step S2, the plant seeds and fruits are crushed and ground into 80-150 meshes.

[0060] Specifically, the ratio of oil to distilled water in step S3 is 1:6.

[0061] S3: Take the crushed oil, add a certain volume of distilled water, and place it in an ultrasonic reactor for pretreatment, and the ultrasonic time is 30 minutes;

[0062] Specifically, the ultrasonic parameters of the ultrasonic reactor in step S3 include ultrasonic temperature and ultrasonic intensity. The ultrasonic temperature is 45° C. and the ultrasonic intensity is 350W.

[0063] S4: performing step-by-step enzymatic hydrolysis: (1) adding complex polysaccharide enzyme for hydrolysis at a temperature of 50°C, a pH of 4.5, and a time of 60 min; (2) alkaline extraction at a pH of 9, a temperature of 60°C, and a time of 35 min; (3) adding protease for hydrolysis at a temperature of 60°C, a pH of 8.5, and a time of 3 h to obtain an enzymatic mixed solution;

[0064] Specifically, in step S4, the complex polysaccharide enzyme in the stepwise enzymatic hydrolysis step (1) includes pectinase, β-glucanase and cellulase, and the volume ratio of the three is 2:1:1, and the enzyme addition amount is 1.0%.

[0065] Specifically, in the step S4, the amount of protease added in the stepwise enzymatic hydrolysis step (3) is 1.5%.

[0066] S5: heating the enzymatic mixed solution to 90°C and maintaining it for 10 minutes to inactivate the enzyme;

[0067] S6: Then centrifuge at a speed of 4500 r / min for 15 min to collect free oil and emulsion;

[0068] S7: adding deionized water to the emulsion, mixing, placing in an ultrasonic cell pulverizer, treating at a certain ultrasonic temperature and ultrasonic intensity for a certain time, taking out, then adjusting the pH of the pretreated emulsion, placing it in a microwave oven, treating at a certain microwave intensity for a certain time, and then centrifuging at a centrifugal speed of 4000 r / min for 10 minutes to obtain free oil II, a water phase mixture and residue;

[0069] Specifically, in step S7, the emulsion is treated at an ultrasonic temperature of 40° C. and an ultrasonic intensity of 350 W for 30 seconds.

[0070] Specifically, in step S7, after the ultrasonic pretreatment, the pH value of the emulsion is adjusted to 4.5.

[0071] Specifically, in the step S7, after adjusting the pH value, the mixture is treated at a microwave intensity of 600 W for 70 seconds.

[0072] S8: Mix the free oil 1 and the free oil 2 to obtain the final vegetable oil.

[0073] As can be seen from the above, in the enzymatic hydrolysis process, firstly, a composite polysaccharide enzyme (pectinase, β-glucanase and cellulase) is used to perform the first step of enzymatic hydrolysis under certain conditions, then alkaline extraction is performed, and then protease is used to perform the second step of enzymatic hydrolysis under certain conditions to obtain an enzymatic hydrolysis mixed solution. The enzymatic hydrolysis efficiency is improved by step-by-step enzymatic hydrolysis; then, the enzymatic hydrolysis mixed solution is heated to certain conditions to inactivate the enzymes, and then centrifuged to further improve the vegetable oil extraction rate.

[0074] Embodiment three:

[0075] This embodiment is basically the same as the second embodiment, except that different demulsification conditions are adopted in the demulsification step. The ultrasonic temperature in step S3 is 45°C, the ultrasonic intensity is 350W, and the ultrasonic time is 30min. The enzymatic hydrolysis conditions, enzyme inactivation conditions and the first centrifugation conditions in the step-by-step enzymatic hydrolysis step are fixed conditions in this embodiment.

[0076] The present invention provides a method for preparing cooking and frying vegetable oil, comprising the following steps:

[0077] S1: Prepare plump and undamaged plant seeds and fruits, wash them with clean water, and then dry them for later use;

[0078] Specifically, the plant seeds and fruits in step S1 include camellia, oil palm, okra and perilla.

[0079] S2: The dried plant seeds and fruits are ground by wet method or dry method according to the moisture content of the different plant seeds and fruits to obtain ground oil;

[0080] Specifically, in step S2, the plant seeds and fruits are crushed and ground into 80-150 meshes.

[0081] Specifically, the ratio of oil to distilled water in step S3 is 1:6.

[0082] S3: Take the crushed oil, add a certain volume of distilled water, and place it in an ultrasonic reactor for pretreatment, and the ultrasonic time is 30 minutes;

[0083] Specifically, the ultrasonic parameters of the ultrasonic reactor in step S3 include ultrasonic temperature and ultrasonic intensity. The ultrasonic temperature is 45° C. and the ultrasonic intensity is 350W.

[0084] S4: performing step-by-step enzymatic hydrolysis: (1) adding complex polysaccharide enzyme for hydrolysis at a temperature of 50°C, a pH of 4.5, and a time of 60 min; (2) alkaline extraction at a pH of 9, a temperature of 60°C, and a time of 35 min; (3) adding protease for hydrolysis at a temperature of 60°C, a pH of 8.5, and a time of 3 h to obtain an enzymatic mixed solution;

[0085] Specifically, in step S4, the complex polysaccharide enzyme in the stepwise enzymatic hydrolysis step (1) includes pectinase, β-glucanase and cellulase, and the volume ratio of the three is 2:1:1, and the enzyme addition amount is 1.0%.

[0086] Specifically, in the step S4, the amount of protease added in the stepwise enzymatic hydrolysis step (3) is 1.5%.

[0087] S5: heating the enzymatic mixed solution to 90°C and maintaining it for 10 minutes to inactivate the enzyme;

[0088] S6: Then centrifuge at a speed of 4500 r / min for 15 min to collect free oil and emulsion;

[0089] S7: adding deionized water to the emulsion, mixing, placing in an ultrasonic cell pulverizer, treating at a certain ultrasonic temperature and ultrasonic intensity for a certain time, taking out, then adjusting the pH of the pretreated emulsion, placing it in a microwave oven, treating at a certain microwave intensity for a certain time, and then centrifuging at a centrifugal speed of 4500 r / min for 10 minutes to obtain free oil II, a water phase mixture and residue;

[0090] Specifically, in step S7, the emulsion is treated at an ultrasonic temperature of 50° C. and an ultrasonic intensity of 400 W for 30 seconds.

[0091] Specifically, in step S7, after the ultrasonic pretreatment, the pH value of the emulsion is adjusted to 5.5.

[0092] Specifically, in the step S7, after adjusting the pH value, the mixture is treated at a microwave intensity of 700 W for 100 s.

[0093] S8: Mix the free oil 1 and the free oil 2 to obtain the final vegetable oil.

[0094] Furthermore, the demulsification rate is calculated as follows:

[0095] Demulsification rate = free oil mass / total oil content in emulsion × 100%.

[0096] In summary, when demulsifying the emulsion, first add deionized water to the emulsion, put it into the ultrasonic temperature of 50 ° C and the ultrasonic intensity of 400 W for pretreatment for 30 seconds, and then use acid and alkali to adjust the pH of the emulsion that has been ultrasonically pretreated to 5.5, and then place it in a microwave oven, treat it at a microwave intensity of 700 W for 100 seconds, and then centrifuge it.

[0097] As can be seen from the above, in the demulsification process, the emulsion is first pretreated with ultrasound, and then the emulsion is treated with microwaves. The present invention demulsifies the emulsion by combining ultrasound with microwaves, which can effectively improve the demulsification rate and further improve the extraction rate of vegetable oil.

[0098] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claim involved.

[0099] The embodiments of the present invention are provided for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for preparing cooking and frying vegetable oil, characterized in that: The following steps are involved: S1: Prepare plump and undamaged plant seeds and fruits, wash them with clean water, and then dry them for later use; S2: The dried plant seeds and fruits are ground by wet method or dry method according to the moisture content of the different plant seeds and fruits to obtain ground oil; S3: Take the crushed oil, add a certain volume of distilled water, and place it in an ultrasonic reactor for pretreatment, and the ultrasonic time is 20-60 minutes; S4: performing step-by-step enzymatic hydrolysis: (1) adding complex polysaccharide enzyme for hydrolysis, the hydrolysis temperature is 40-60°C, the pH is 4-5, and the time is 40-60 min; (2) alkaline extraction, the alkaline extraction parameters are pH 8-9, temperature 50-60°C, and time 30-40 min; (3) adding protease for hydrolysis, the hydrolysis temperature is 40-60°C, pH 8-9, and time is 2-3 h, to obtain an enzymatic mixed solution; S5: heating the enzymatic mixed solution to 80-90°C and maintaining it for 10 minutes to inactivate the enzyme; S6: Then centrifuge at a speed of 4000-4500 r / min for 10-15 min to collect free oil and emulsion; S7: adding deionized water to the emulsion, mixing, placing in an ultrasonic cell pulverizer, treating at a certain ultrasonic temperature and ultrasonic intensity for a certain time, taking out, then adjusting the pH of the pretreated emulsion, placing it in a microwave oven, treating at a certain microwave intensity for a certain time, and then centrifuging at a centrifugal speed of 4000-4500 r / min for 10-15 min to obtain free oil II, a water phase mixture and residue; S8: Mix the free oil 1 and the free oil 2 to obtain the final vegetable oil.

2. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: In the step S2, the plant seeds and fruits are crushed and ground into 80-150 meshes.

3. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: The oil-to-distilled water ratio in step S3 is 1:

6.

4. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: The ultrasonic parameters of the ultrasonic reactor in step S3 include ultrasonic temperature and ultrasonic intensity. The ultrasonic temperature is 40-45° C. and the ultrasonic intensity is 300-400W.

5. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: In the step S4, the complex polysaccharide enzyme in the stepwise enzymolysis step (1) includes pectinase, β-glucanase and cellulase, and the volume ratio of the three is 2:1:1, and the enzyme addition amount is 1.0%.

6. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: In the step S4, the amount of protease added in the stepwise enzymatic hydrolysis step (3) is 1.5%.

7. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: In the step S7, the emulsion is treated at an ultrasonic temperature of 40-60°C and an ultrasonic intensity of 350-500W for 30-50s.

8. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: In the step S7, after the ultrasonic pretreatment, the pH value of the emulsion is adjusted to 4.5-5.

5.

9. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: In the step S7, after adjusting the pH value, the mixture is treated at a microwave intensity of 600-700 W for 70-100 s.

10. The method for preparing a cooking and frying vegetable oil according to claim 1, characterized in that: The plant seeds and fruits in step S1 include camellia, oil palm, okra and perilla.

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