Method for preparing plant-based single cream from citrus peel residues, starch and vegetable oil

Abstract

The invention discloses a method for preparing plant-based single cream from citrus peel residues, starch and vegetable oil. The method comprises the following steps: pretreating citrus peel pomace to obtain peel pomace A; placing the peel residue A in a blasting pressure tank for blasting treatment to obtain a filter residue B; adding water and a hydrogen peroxide solution into the filter residue B, stirring and filtering to obtain a filter residue C, adding water into the filter residue C, heating the water, firstly adding a part of pregelatinized starch, uniformly stirring, then adding the residual starch, heating and boiling the system together, and then passing through a colloid mill to obtain a compound D; adding vegetable oil into the mixture D, and performing high-pressure homogenization to obtain a mixture E; and treating the mixture E in a high-voltage electric field to obtain the single cream substitute F. The brand-new plant-based single cream is obtained and can replace traditional single cream.

Description

Technical Field

[0001] The invention belongs to the field of food science, and in particular relates to a method for preparing vegetable-based cream by using citrus peel residue, starch and vegetable oil. Background Art

[0002] Cream is widely used in baking, beverages and other food processing fields, but it is directly derived from cow's milk, which is costly and has limited applications. In addition, in recent years, plant-based foods have developed rapidly, and people's demand for animal cream has a clear downward trend. Therefore, there is a broad market space for developing a non-animal source of cream substitute products.

[0003] There are currently three main types of animal cream substitutes on the market.

[0004] One is hydrogenated vegetable oil, but the trans fatty acids produced by hydrogenation are harmful to health and their market acceptance is decreasing.

[0005] The second is refined palm oil products. Although they can avoid the hazards caused by hydrogenation, they are limited by the taste and quality of palm oil, and the refining process is complicated and costly, so consumers do not accept them very much.

[0006] The third is the emerging emulsion gel, which is a composite structure system prepared by emulsification and gelation process using proteins, polysaccharides, vegetable oils, emulsifiers, stabilizers, etc. as main ingredients. However, emulsion gel generally has the problem of low whipping rate. In particular, the low melting point of the fat in the emulsion gel and good fluidity at room temperature are the key reasons for the poor whipping properties of emulsion gel cream. Summary of the invention In order to solve the above problems, the present invention aims to provide a method for preparing plant-based cream using citrus peel residue, starch and vegetable oil. The hydrogen bonds between the fiber crystals are destroyed by high-pressure blasting treatment, so that the structure is loose, more hydrophobic groups and capillaries are exposed, which is conducive to combining with oils and fats, and then hydrogen peroxide is used to remove lignin in the peel residue to prevent agglomeration. At the same time, high-branched starch is introduced, and the branched starch forms a soft and flowable system with water. After cellulose is added, it embodies rigid support and plays an oil absorption role. The semi-fiber plays an adhesion role, connects starch and fiber, and pectin plays an emulsifying and stabilizing role, reduces interfacial tension, and is conducive to the subsequent addition of oils and fats and the stability of the system. Finally, through high-pressure homogenization, the vegetable oil is evenly dispersed in the system, thereby affecting the crystal structure of the oil, changing the melting point of the vegetable oil, and improving the whipping property of the overall system, and a new plant-based cream is obtained, which can replace traditional cream.

[0007] The technical solution of the present invention is as follows: a method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil, the method comprising the following steps: Step 1: pretreatment of citrus peel residue: grind the citrus peel residue after squeezing the juice with water, filter to obtain filter residue, rinse the filter residue with water to remove pigments and cold water soluble impurities, and obtain peel residue A; Step 2: High-pressure blasting treatment: Place the skin residue A in a blasting pressure tank for blasting treatment to destroy the hydrogen bonds between the fiber crystals, loosen the structure, expose more hydrophobic groups and capillaries, which is conducive to fusion with oil (oil absorption), and obtain filter residue B; Step 3: Hydrogen peroxide treatment: Add water and hydrogen peroxide solution to the residue B and stir to remove lignin in the skin residue. Then heat it to remove the residual hydrogen peroxide and filter to obtain the residue C, which is a mixture of pectin-fiber-hemicellulose. (lignin has poor solubility and there are strong interactions between molecules (such as hydrogen bonds and л-л stacking), which easily cause agglomeration and affect its uniform dispersion in the material.) Step 4: Boiling and mixing: Add water to the filter residue C, heat the water to 60-80°C, first add a portion of pregelatinized amylopectin, stir evenly, wait for the starch to completely absorb water and swell, then add the remaining pregelatinized starch, heat the system together and boil for 20-30 min, then pass the boiled mixture through a colloid mill while hot to fully mix it, and obtain a complex D composed of pectin-cellulose-hemicellulose-amylopectin; wherein, amylopectin forms a soft and flowable system with water, cellulose provides rigid support after addition and plays an oil absorption role, hemicellulose plays an adhesion role to connect starch and fiber, pectin plays an emulsifying and stabilizing role to reduce interfacial tension, which is beneficial to the subsequent addition of oil and fat and the stability of the system. (Amylose is prone to aging and crystallization, and is a hard and brittle gel, which is not suitable for use. Amylopectin gel is naturally soft and does not harden at low temperatures) (Function of pectin: Enhance emulsification stability: In a starch gel system containing oil components, pectin can be used as an emulsifier to reduce the surface tension of the oil-water interface, so that the oil is evenly dispersed in the system, forming a stable emulsified structure to prevent the oil from floating or agglomerating) Step 5: High-pressure homogenization: Add vegetable oil to mixture D and homogenize it at a pressure of 20-60 MPa to ensure that the oil and water phases are fully mixed. The cellulose in D is shear-resistant, which is beneficial to maintaining the rigid structure of the entire system (keeping the cream stiff and not easy to collapse), and promoting the oil to form fine crystals and transform to a more stable β crystal form to obtain mixture E; Step 6: Prepare emulsion by high-voltage electric field: Place mixture E in a high-voltage electric field for thorough mixing to obtain a cream substitute F; (pectin has a negative charge, and electric field treatment can make the system more stable).

[0008] Preferably, in step (1), in step 1, the citrus peel residue includes mandarin orange peel residue, orange peel residue or grapefruit peel with the pulp removed; The citrus peel residue after squeezing the juice is ground with water, passed through a 50-70 mesh gauze or filter screen to obtain a filter residue, and the filter residue is rinsed with 3-5 times water to further remove water-soluble sugars and pigments, etc., to obtain peel residue A.

[0009] Preferably, in step 2, the blasting conditions are: a pressure of 10-100 MPa, 5-10 cycles, each lasting 3-10 seconds.

[0010] Preferably, in step 3, 10-20 times of water is added to the residue B, and 2-10% hydrogen peroxide solution is added at the same time, and the system is controlled to be stirred at 20-50° C. for 2-4 h to remove lignin in the plant sample through its strong oxidizing property, thereby obtaining a mixture of pectin-cellulose-hemicellulose, and then the temperature is raised to above 80° C. to remove hydrogen peroxide, and the residue C is obtained by filtration.

[0011] Preferably, in step 4, the starch used in step 4 is pre-gelatinized and pre-treated before step 4 is performed. The pre-treatment method is to mix amylopectin and water in a ratio of 1: (15-25) to form a uniform starch milk, add the starch milk to a screw extruder, and the screw rotation speed is 100-400 r / min, the pressure is 0.5-3 MPa, and the extrusion temperature is 120-200°C to obtain pre-gelatinized starch. The starch milk is added to the screw extruder, and the starch molecular chain is broken and the hydrogen bond is disconnected by high temperature, high pressure and shear force, and its regularly arranged micelle structure is destroyed. Then, it is extruded through a small hole at high pressure, and the starch particles with broken hydrogen bonds, porous and no obvious crystallization are obtained after extrusion, puffing and drying. Prepare pre-gelatinized starch with high viscoelasticity, water retention, solubility in cold water and good freezing stability.

[0012] Further preferably, in step 4, the mixture is boiled and mixed: 10-20 times of water is added to the residue C, the water is heated to 60-80°C, a portion of pregelatinized amylopectin (the amount added accounts for 50% of the total amount of amylopectin added) is first added, the content of which is higher than the fiber, and after stirring evenly, the remaining starch is added after the starch completely absorbs water and swells, and the total amount of amylopectin added is 2-6 times the mass of the residue C. In this way, the aggregation of starch particles is reduced, thereby helping the starch to better combine with the components of the citrus peel residue, and improving the emulsification effect and stability of the final product. The system is heated and boiled together for 20-30 min, and then the boiled mixture is passed through a colloid mill while hot to fully mix it to obtain a mixture D.

[0013] More preferably, in step 4, the branched ratio of amylopectin is greater than 90%, and preferably, the types of amylopectin include but are not limited to glutinous rice starch, glutinous corn starch or other starches or a combination thereof. The amylopectin is subjected to spiral extrusion, puffing and drying to prepare pregelatinized starch for mixing with fiber.

[0014] Preferably, in step 5, the vegetable oil is palm oil, coconut oil, walnut oil, soybean oil, corn oil or olive oil or a combination thereof.

[0015] Preferably, in step 5, the high pressure homogenization condition is 20-60 MPa, and the oil and water phases are fully mixed while maintaining the quality of the cellulose. Preferably, in step 6, the voltage range is 2-5 kV, the distance between the electrode and the liquid surface is controlled at 2-10 cm, the processing time is 1-5 min, the frequency is 50-1000 Hz, and the pulse width is 1-5 µs to achieve mixing.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. Through the above steps, especially regulating the order of high-pressure blasting and hydrogen peroxide treatment steps, the content and proportion of soluble fiber (pectin, etc.) and insoluble fiber (cellulose, hemicellulose and lignin) in citrus peel residue can be effectively adjusted, and more hydrophobic groups and capillaries can be fully exposed, which is conducive to the fusion with oil, and then the crystal form of oil is changed, which plays an important role in improving the whipping rate of cream substitute.

[0017] 2. Through the above steps, a complex composed of pectin-cellulose-hemicellulose-branched starch can be established. In particular, high-branched starch is selected, and the gel formed by it is naturally soft and does not harden at low temperatures. It forms a soft and flowable system with water. After the addition of cellulose, it shows rigid support and plays an oil absorption role. The hemicellulose plays an adhesion role, connecting starch and fiber. Pectin plays an emulsifying and stabilizing role, reduces interfacial tension, and is conducive to the subsequent addition of oil and fat and the stability of the system, thereby effectively changing the crystal form of the oil, increasing the relative content of the β′ form and transforming it to a more stable β crystal form, thereby improving the whipping rate of the emulsion gel. This technology can be widely used in the fields of food, cosmetics and biomedicine, especially in products with high requirements for the stability and texture of the emulsion gel.

[0018] 3. The present invention uses high-voltage homogenization and high-voltage electric field to fully mix oil and water, not only making the oil form fine crystals and transforming to a more stable β crystal form, but also retaining the upright structure of cellulose, and treating the charged ions by electric field to make the system more stable. Through this treatment, the emulsification stability of the cream is improved by 2-3 times, and the whipping performance is improved to about 300%, meeting the functional requirements of food processing for cream substitutes.

[0019] 4. The present invention uses citrus peel residue, starch and vegetable oil, has low raw material cost and is conducive to industrialization. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Example 1 XRD spectrum of pectin-cellulose-hemicellulose-pullulan-vegetable oil composite system. DETAILED DESCRIPTION

[0021] The following will be combined with the specific embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. The embodiments described 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 making creative work belong to the protection scope of the present invention.

[0022] In the context of this specification, except for the contents explicitly described, any matters or items not mentioned directly use the technology known in the art. Moreover, any embodiment described in this patent can be freely combined with one or more other embodiments described in this patent, and the technical solutions or technical ideas formed thereby are regarded as part of the original disclosure or original record of the present invention, and should not be regarded as new content not disclosed in this patent, unless a person skilled in the art considers that the combination is obviously unreasonable.

[0023] The data points disclosed in the present invention include not only the specifically disclosed numerical points, but also the endpoints of each numerical range. Any combination of these data points should be regarded as the disclosed or recorded range of the present invention, regardless of whether these numerical points are disclosed one by one in this article.

[0024] Results comparison test method: Determination of whipping rate: Take out the cream substitute F and stir it with an electric mixer for 2 minutes at room temperature. Fill the whipped cream foam into a plastic dish, make it completely full and spread it, and smooth the surface with a spatula. Calculate the whipping rate according to the following formula, and repeat the measurement 3 times for each sample.

[0025] Whipping rate % = (M1-M2) / M2×100% Where: M1 is the mass of the same volume of unwhipped cream, g; M2 is the mass of the same volume of whipped cream, g. Determination of oil crystal form: Take a certain amount of sample and fill it into the circular hole of the test piece, flatten it with a glass slide, and remove the excess sample. Use a ceramic X-ray tube, Cu target, scan from 12° to 30° at a scanning rate of 5° / min, and set the step size to 0.05° for wide-angle XRD analysis.

[0026] Modulus of the emulsion: Frequency scanning was performed using a rotational rheometer: the Oscillation frequency test mode was selected, the test temperature was 25°C, the frequency range was 1.0-100 rad / s, the data acquisition mode was logarithmic mode (log), 10 points were taken at each order of magnitude, and an oscillation scanning test was performed.

[0027] Particle size determination: The average droplet diameter of the emulsion was measured using a laser particle size analyzer. The stirring speed was set to 2000 r / min, and the sample was dispersed in distilled water to an appropriate shading value (1-10%) to avoid multiple light scattering effects. Three parallel measurements were performed, and the volume-weighted average D(4,3) was used to represent the average particle size of the emulsion droplets.

[0028] The starch used in step 4 described in the following embodiment is pre-gelatinized and pre-treated before step 4 is performed. The pre-treatment method is to mix amylopectin and water in a ratio of 1:20 to form a uniform starch milk, add the starch milk to a screw extruder, the screw rotation speed is 300 r / min, the pressure is 2.5 MPa, and the extrusion temperature is 150°C to obtain pre-gelatinized starch. The starch milk is added to the screw extruder, and the starch molecular chain is broken and the hydrogen bond is disconnected by high temperature, high pressure and shear force, and its regularly arranged micelle structure is destroyed. Then, it is extruded through a small hole at high pressure, and the hydrogen bond is disconnected, porous, and starch particles without obvious crystallization are obtained after extrusion, expansion and drying. Prepare pre-gelatinized starch with high viscoelasticity, water retention, solubility in cold water, and good freezing stability. Example 1 Step 1: Orange Peel Pretreatment The orange peel residue after juicing is ground with water and passed through a 60-mesh gauze or filter to obtain a filter residue. The filter residue is rinsed with 4 times water to remove water-soluble sugars and pigments, etc., to obtain peel residue A.

[0029] Step 2: High-pressure blasting treatment The skin residue A was placed in a blasting pressure tank, a pressure of 50 MPa was applied, and 10 cycles were performed, each lasting 3 seconds, to obtain the filter residue B.

[0030] Step 3: Hydrogen Peroxide Treatment Add 15 times of water to the residue B and add 5% hydrogen peroxide solution at the same time, control the system to stir at 30°C for 2 h, then heat to 80°C, remove hydrogen peroxide, and filter to obtain the residue C.

[0031] Step 4: Boil and mix Add 15 times of water to the residue C and add 5% of glutinous rice starch at the same time. After the starch completely absorbs water and swells, add the remaining 5% of starch. After heating and boiling for 25 minutes, pass the mixed solution through a colloid mill while it is hot to fully mix, thereby obtaining a compound D.

[0032] Step 5: High-pressure homogenization 30% walnut oil was added to the composite D, and the mixture was mixed by a high-pressure homogenizer at a pressure of 50 MPa to obtain a mixture E.

[0033] Step 6: High voltage electric field preparation of emulsion The mixture E was placed in a high voltage electric field with a voltage range of 3 kV, a distance between the electrode and the liquid surface of 5 cm, a treatment time of 3 min, a frequency of 500 Hz, and a pulse width of 3 µs to fully mix it to obtain a cream substitute F.

[0034] Comparative Example 1 Based on Example 1, the glutinous rice starch in step 4 was not pre-gelatinized before being added, and the rest was the same as Example 1.

[0035] Example 2 Step 1: Pretreatment of grapefruit peel residue The grapefruit peel residue after juicing is ground with water and passed through a 60-mesh gauze or filter to obtain a filter residue. The filter residue is rinsed with 4 times water to remove water-soluble sugars and pigments, etc., to obtain a peel residue A.

[0036] Step 2: Hydrogen Peroxide Treatment Add 15 times of water to the skin residue A and add 5% hydrogen peroxide solution at the same time, control the system to stir at 30°C for 2h, then heat to 80°C, remove hydrogen peroxide, and filter to obtain residue B.

[0037] Step 3: High-pressure blasting treatment The filter residue B was placed in a blasting pressure tank, and a pressure of 50 MPa was applied for 10 cycles, each lasting 3 seconds, to obtain the filter residue C.

[0038] Step 4: Boil and mix Add 15 times of water to the residue C and add 5% of glutinous rice starch at the same time. After the starch completely absorbs water and swells, add the remaining 5% of starch. After heating and boiling for 25 minutes, pass the mixed solution through a colloid mill while it is hot to fully mix, and obtain a complex D.

[0039] Step 5: High-pressure homogenization 30% walnut oil was added to the composite D, and the mixture was mixed by a high-pressure homogenizer at a pressure of 50 MPa to obtain a mixture E.

[0040] Step 6: High voltage electric field preparation of emulsion The mixture E was placed in a high voltage electric field with a voltage range of 3 kV, a distance between the electrode and the liquid surface of 5 cm, a treatment time of 3 min, a frequency of 500 Hz, and a pulse width of 3 µs to fully mix it to obtain a cream substitute F.

[0041] Example 3 Step 1: Pre-treatment of mandarin orange peel residue The orange peel residue after juicing is ground with water and passed through a 60-mesh gauze or filter to obtain a filter residue. The filter residue is rinsed with 4 times water to remove water-soluble sugars and pigments, etc., to obtain peel residue A.

[0042] Step 2: High-pressure blasting treatment The skin residue A was placed in a blasting pressure tank, a pressure of 50 MPa was applied, and 10 cycles were performed, each lasting 3 seconds, to obtain the filter residue B.

[0043] Step 3: Hydrogen Peroxide Treatment Add 15 times of water to the residue B and add 5% hydrogen peroxide solution at the same time, control the system to stir at 30°C for 2.5 h, then heat to 80°C, remove hydrogen peroxide, and filter to obtain the residue C.

[0044] Step 4: Boil and mix Add 15 times of water to the residue C and add 5% corn starch at the same time. After the starch completely absorbs water and swells, add the remaining 5% starch. After heating and boiling for 25 minutes, pass the mixed solution through a colloid mill while it is hot to fully mix, and obtain a complex D.

[0045] Step 5: High-pressure homogenization 30% walnut oil was added to the composite D, and the mixture was mixed by a high-pressure homogenizer at a pressure of 50 MPa to obtain a mixture E.

[0046] Step 6: High voltage electric field preparation of emulsion The mixture E was placed in a high voltage electric field with a voltage range of 3 kV, a distance between the electrode and the liquid surface of 5 cm, a treatment time of 3 min, a frequency of 500 Hz, and a pulse width of 3 µs to fully mix it to obtain a cream substitute F. Table 1

[0047] As shown in Table 1 above, the present invention can effectively improve the whipping rate of traditional cream, increase the melting point of fat, increase the relative content of the β′ form of the fat crystal and transform it to the more stable β crystal form, thereby improving the whipping rate of the cream substitute. Example 1 uses two key innovative operations of the present invention, and the interplanar spacing of the characteristic diffraction peak in the composite moves from 4.55 Å to 4.47 Å, which is better than the traditional cream product.

[0048] Example 2 During the citrus fiber extraction process, hydrogen peroxide treatment was first performed and then high-pressure blasting treatment was performed. The fiber did not reach a sufficient degree of looseness and lost some components, which was not conducive to sufficient contact with branched starch in the later stage. The mutual force and interfacial effect were not strong, resulting in weak stability of the final emulsion and a lower whipping rate than Example 1.

[0049] Example 3 The content of amylopectin in the added corn starch is lower than that in glutinous rice starch. The formed pectin-cellulose-hemicellulose-amylopectin complex has weak interaction, limited oil adsorption capacity, unstable oil-water interface, and lower whipping rate than Example 1.

[0050] Comparative Example 1 The starch in the pectin-cellulose-hemicellulose-branched starch composite system has not been pre-gelatinized. The pre-gelatinization treatment will affect the molecular structure, texture properties and rheological properties of the branched starch. Gelatinization increases the water solubility of starch, loosens the molecular chains, and reduces the binding force between the molecular chains. These changes enable the branched starch to better integrate with cellulose and hemicellulose, thereby optimizing the structure and performance of the entire system. The lack of gelatinization directly affects the functionality of the branched starch, resulting in a 35% decrease in the whipping rate compared to Example 1.

[0051] Example 4 Based on Example 1, step 2: high-pressure blasting treatment conditions were changed (the skin residue A was placed in a blasting pressure tank, a pressure of 50 MPa was applied, and 10 cycles were performed, each lasting 3 seconds to obtain filter residue B), and the rest were the same as Example 1.

[0052] Example 4-1: The blasting conditions are: 8 MPa pressure, 10 cycles, each lasting 3 seconds.

[0053] Example 4-2: The blasting conditions are: a pressure of 40 MPa, 10 cycles, each lasting 3 seconds.

[0054] Example 4-3: The blasting conditions are: a pressure of 100 MPa, 10 cycles, each lasting 3 seconds.

[0055] Table 2

[0056] As can be seen from Table 2 above, the rheological properties of the traditional cream substitute prepared by the present invention are optimized. The high-pressure bursting pressure in step 2 of Example 4-2 is 40 MPa, and the rest is the same as Example 1. When the frequency is 1 Hz, the storage modulus of the emulsion in the composite increases to 200 Pa, and the loss modulus increases to 150 Pa, and the elastic and viscosity properties are enhanced. After the citrus peel residue absorbs water and swells, it interacts with the amylopectin to form a physical cross-linked structure, which improves the network strength and structural stability of the emulsion, while the traditional cream has a lower storage modulus and loss modulus due to its component characteristics.

[0057] Example 4-1: The blasting pressure of 8 MPa was used to treat the leather residue. The pressure was too low, which only caused a slight change in the fiber surface morphology. The roughness and specific surface area could not be increased, and the structure was not sufficiently loose. The hydrophobic groups and capillaries were not fully exposed. The strength and elasticity of the fiber may remain at the original level, which is not conducive to its adsorption of oil. This resulted in the failure to fully treat with hydrogen peroxide in step 3 to remove lignin in the fiber, and the obtained pectin-cellulose-hemicellulose mixture had an uneven structure, and the effect was definitely not as good as that of Example 1.

[0058] Example 4-3: Under a bursting pressure of 100 MPa, the fibers rupture and structural changes affect the pore structure and performance of the fibers, increasing their brittleness and possibly causing the discharge of some water, which affects the elasticity, toughness and strength of the fibers. The resulting pectin-cellulose-hemifibrillar composite structure is fragile and has a lower loss modulus than that of Example 1.

[0059] Example 5 Based on Example 1, step 6 was changed: the mixture E was placed in a high voltage electric field with a voltage of 3 kV, a distance between the electrode and the liquid surface of 5 cm, a treatment time of 3 min, a frequency of 500 Hz, and a pulse width of 3 µs to fully mix the mixture, thereby obtaining a cream substitute F.

[0060] Example 5-1: The voltage is 2 kV, the distance between the electrode and the liquid surface is 5 cm, the processing time is 3 min, the frequency is 500 Hz, and the pulse width is 3 µs.

[0061] Example 5-2: The voltage is 5 kV, the distance between the electrode and the liquid surface is 5 cm, the processing time is 3 min, the frequency is 500 Hz, and the pulse width is 3 µs.

[0062] Example 5-3: The voltage is 6 kV, the distance between the electrode and the liquid surface is 5 cm, the processing time is 3 min, the frequency is 500 Hz, and the pulse width is 3 µs.

[0063] Table 3

[0064] As shown in Table 3 above, the present invention can effectively improve the whipping rate of traditional cream. The voltage in step 6 of Example 5-2 is 5 kV, and the rest is the same as Example 1. The average particle size of the pectin-cellulose-hemicellulose-branched starch-vegetable oil system is about 40 μm. The smaller the particle size, the more stable the emulsion, and thus the higher the whipping rate.

[0065] Example 5-1 has a high voltage electric field voltage of 2 kV. The lower voltage may not be enough to significantly affect the surface charge of particles such as pectin, and the electrostatic repulsion is reduced. At the same time, the oil droplets and particles are difficult to be fully dispersed, resulting in the increase of the emulsion particle size, the decrease of the emulsion stability, and the easy occurrence of aggregation or stratification, which affects the stability of the pectin-cellulose-hemicellulose-branched starch-vegetable oil complex, and the effect is not as good as that of Example 1.

[0066] Example 5-3 6 kV high voltage electric field voltage, too high voltage causes excessive shear force, destroys the microstructure of the emulsion, destroys the pectin with negative charge as an emulsifier stabilizer, and further affects the stability of the oil-water interface. At the same time, too high voltage will cause local high temperature, which will lead to thermal degradation of some components in the pectin-cellulose-hemicellulose-branched starch-vegetable oil complex or oxidation of oil, affecting the quality of the cream substitute.

[0067] The technical solution of the present invention is explained through the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above specific embodiments to be implemented. Any improvements made by technicians in the relevant field based on the present invention, or equivalent replacement of the materials selected by the present invention, etc., fall within the scope of protection of the patent.

Claims

1. A method for preparing a vegetable-based cream using citrus peel residue, starch and vegetable oil, characterized in that: The method comprises the following steps: Step 1: pretreatment of citrus peel residue: grind the citrus peel residue after squeezing the juice with water, filter to obtain filter residue, rinse the filter residue with water to remove pigments and cold water soluble impurities, and obtain peel residue A; Step 2: high-pressure blasting treatment: placing the skin residue A in a blasting pressure tank for blasting treatment to obtain filter residue B; Step 3: Hydrogen peroxide treatment: add water and hydrogen peroxide solution to the filter residue B, stir, and filter to obtain the filter residue C, which is a mixture of pectin-cellulose-hemicellulose; Step 4: Boiling and mixing: add water to the filter residue C, heat the water, add a portion of the amylopectin first, stir evenly, wait for the starch to completely absorb water and swell, then add the remaining starch, heat the system together and boil, then pass the boiled mixture through a colloid mill while it is hot to obtain a complex D composed of pectin-cellulose-hemicellulose-amylopectin; Step 5: High-pressure homogenization: Add vegetable oil to mixture D and homogenize under high pressure at 20-60 MPa to obtain mixture E; Step 6: Preparing an emulsion by high-voltage electric field: The mixture E is placed in a high-voltage electric field for thorough mixing, thereby obtaining a cream substitute F.

2. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 1, characterized in that: In step 1, the citrus peel residue includes mandarin orange peel residue, orange peel residue or grapefruit peel with pulp removed; The citrus peel residue after squeezing the juice is ground with water, passed through a 50-70 mesh gauze or filter screen to obtain a filter residue, and the filter residue is rinsed with 3-5 times water to further remove water-soluble sugars and pigments, etc., to obtain peel residue A.

3. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 1, characterized in that: In step 2, the blasting conditions are: a pressure of 10-100 MPa, 5-10 cycles, each lasting 3-10 seconds.

4. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 1, characterized in that: In step 3, 10-20 times of water is added to the filter residue B, and 2-10% hydrogen peroxide solution is added at the same time, and the system is controlled to be stirred at 20-50° C. for 2-4 hours to obtain a mixture of pectin-cellulose-hemicellulose, which is then heated to above 80° C., hydrogen peroxide is removed, and filter residue C is obtained.

5. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 1, characterized in that: The starch used in step 4 is pre-gelatinized and pre-treated before step 4 is performed. The pre-treatment method is to mix amylopectin and water in a ratio of 1: (15-25) to form a uniform starch milk, and add the starch milk to a screw extruder. The screw rotation speed is 100-400 r / min, the pressure is 0.5-3 MPa, and the extrusion temperature is 120-200°C to obtain pre-gelatinized starch.

6. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 5, characterized in that: In the step 4, boiling and mixing: add 10-20 times of water to the filter residue C, heat the water to 60-80° C., first add a portion of pregelatinized branched starch, stir evenly, wait for the starch to completely absorb water and swell, then add the remaining pregelatinized starch, heat the system together and boil for 20-30 min, then grind the boiled mixture through a colloid mill while hot for 9-15 min to fully mix it, and obtain a mixture D.

7. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 6, characterized in that: In step 4, the amount added accounts for 50% of the total amount of amylopectin added, and the total amount of amylopectin added is 2-6 times the mass of the filter residue C; the amylopectin branch ratio is greater than 90%, and preferably, the types of amylopectin include glutinous rice starch, glutinous corn starch or others or their combinations.

8. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 1, characterized in that: In step 5, the vegetable oil is palm oil, coconut oil, walnut oil, soybean oil, corn oil or olive oil or a combination thereof.

9. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 1, characterized in that: In step 5, the high-pressure homogenization condition is 20-60 MPa, which fully mixes the oil and water phases while maintaining the quality of the cellulose.

10. The method for preparing vegetable-based cream using citrus peel residue, starch and vegetable oil according to claim 1, characterized in that: In step 6, the voltage range is 2-5 kV, the distance between the electrode and the liquid surface is controlled at 2-10 cm, the processing time is 1-5 min, the frequency is 50-1000 Hz, and the pulse width is 1-5 µs.

Images