A method for preparing a corn starch gel

Abstract

The application provides a preparation method of corn starch gel and relates to the technical field of food processing.The preparation method of the waxy corn starch gel comprises the following steps: mixing amylose paste and waxy corn starch paste, and obtaining the gel after injection molding and standing; the mass ratio of the amylose in the amylose paste to the waxy corn starch in the waxy corn starch paste is 0-1:2-3.The three-dimensional network structure of the waxy corn starch gel is more uniform and the pore size is smaller after adding the amylose in the waxy corn starch, the amylose is closely covered on the waxy corn starch gel matrix, a more stable network structure is formed, and the gelatinization characteristics of the waxy corn starch are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a method for preparing corn starch gel. Background Art

[0002] Starch, a macromolecular polysaccharide, not only supports plant growth and development but also plays an important role in human life. Starch is typically stored in the seeds of cereals and legumes, as well as in the tubers, rhizomes, and other storage organs of some plants. Natural starch has a semi-crystalline structure, primarily composed of amylose and amylopectin molecules. The branches of amylopectin can form double helices and further form crystalline lamellae, while their branch points form amorphous lamellae. Alternating crystalline and amorphous lamellae serve as the basis for further construction of semi-crystalline growth rings, which are primarily composed of single amylose molecules. Starch granules have varying morphological characteristics and sizes due to differences in plant origin and organ, starch granule development, and environmental factors. Starch is widely used in the food industry as an emulsifier, stabilizer, thickener, and edible coating.

[0003] Gelatinization and retrogradation are two important steps in the manufacture of these starch-based products. During the gelatinization process, starch granules gradually absorb water and swell. At the same time, the water molecules inside the starch granules destroy the semi-crystalline structure of the starch, turning it into amorphous starch. When the starch granules swell to a certain extent, they begin to rupture and then release starch molecules. Researchers have now concluded that the presence of swollen starch granules is conducive to increasing the viscosity of the starch paste and enhancing the gel strength. However, current studies have only investigated the effect of swollen starch granules on the final properties of starch-based products, and have always ignored the role of dissolved amylose molecules in gelatinized starch.

[0004] When native semi-crystalline granules are heated above their characteristic melting temperature with little or no shear, they swell and release amylose molecules without completely dissolving. Therefore, gelatinized starch typically contains a mixture of dissolved polymers (primarily low-molecular-weight leached amylose) and swollen starch granules. However, the importance of dissolved amylose in determining the properties of cooked starch is often underestimated in studies that consider gelatinized starch as containing both dissolved polymers and swollen starch granules.

[0005] Compared to regular corn starch, waxy corn starch contains little or no amylose and has a higher gelatinization viscosity. It is often used in the production of puddings and sauces to provide stability and thickening properties. However, due to its low amylose content, waxy corn starch has a slower retrogradation rate, which is not conducive to forming a uniform and tightly ordered gel structure during the retrogradation process. As a result, waxy corn starch pastes often fail to form a strong gel structure after retrogradation, which limits its industrial application. Summary of the Invention

[0006] Therefore, the present application aims to provide a preparation method of corn starch gel, which improves the gel properties by adjusting the ratio of waxy corn starch and amylose.

[0007] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions.

[0008] The present application provides a preparation method of corn starch gel, which comprises: mixing amylose paste and waxy corn starch paste, and injecting into a mold and standing to obtain the gel; the mass ratio of amylose in the amylose paste to waxy corn starch in the waxy corn starch paste is 0-1:2-3.

[0009] Preferably, the amylose is potato amylose.

[0010] Preferably, the preparation of the amylose comprises: immersing potato starch suspension in a water bath at 58℃ for 1h, centrifuging, repeating the immersion and centrifugation of the precipitate for 2 times, combining the supernatant, freeze-drying, and grinding to obtain the amylose.

[0011] Preferably, the mass concentration of the potato starch suspension is 6%.

[0012] Preferably, the centrifugation is performed at a speed of 4000g for 45min.

[0013] Preferably, the preparation of the amylose paste comprises: mixing the amylose with water, and heating by microwave until clear and transparent.

[0014] Preferably, the mass-volume ratio of the amylose to water is 0.25-1:20g / mL.

[0015] Preferably, the preparation of the waxy corn starch paste comprises: mixing the waxy corn starch with water, and heating at 80℃ for 10min.

[0016] Preferably, the mass-volume ratio of the waxy corn starch to water is 2-2.75:10g / mL or 3:30g / mL.

[0017] The present application also provides the waxy corn starch gel obtained by the above-mentioned preparation method.

[0018] Compared with the prior art, the present application has the following beneficial effects:

[0019] The present invention provides a method for preparing a corn starch gel, comprising: mixing an amylose paste and a waxy corn starch paste, injection molding, and allowing the mixture to stand to obtain a gel; wherein the mass ratio of amylose in the amylose paste to waxy corn starch in the waxy corn starch paste is 0-1:2-3. Adding amylose to the waxy corn starch in the present invention results in a more uniform three-dimensional network structure and smaller pores in the waxy corn starch gel. The amylose is tightly coated on the waxy corn starch gel matrix, indicating a more stable network structure and improved gel properties of the waxy corn starch. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 : Microscopic images of waxy corn starch before and after gelatinization observed under bright field (A, B) and cross-polarized light (a, b);

[0021] Figure 2 : Storage modulus (G′) and loss modulus (G″) (A) and loss factor (tanδ) (B) of waxy corn starch-based gels with different amounts of amylose added as a function of angular frequency. Closed symbols: G′; open symbols: G″;

[0022] Figure 3 : Pictures of WCS and WCS-AM gels;

[0023] Figure 4 : SEM images of WCS-AM gels; (A) WCS, (B) WCS-8.3% AM, (C) WCS-16.7% AM, (D) WCS-25.0% AM, (E) WCS-33.3% AM;

[0024] Figure 5 :FTIR spectrum of WCS-AM gel (A) and 1047cm -1 / 1022cm -1 The value of (B);

[0025] Figure 6 : SAXS curves of WCS and WCS-AM gels;

[0026] Figure 7 : XRD patterns of WCS and WCS-AM gels. DETAILED DESCRIPTION

[0027] The invention provides a method for preparing corn starch gel, comprising: mixing amylose paste and waxy corn starch paste, injection molding, and standing to obtain a gel; the mass ratio of amylose in the amylose paste to waxy corn starch in the waxy corn starch paste is 0-1:2-3.

[0028] The amylose starch is preferably potato amylose starch; the preparation of the amylose starch preferably comprises: immersing a potato starch suspension in a water bath at 58℃ for 1h, centrifuging, repeating the immersion and centrifugation of the precipitate for 2 times, combining the supernatant, freeze-drying, and grinding to obtain the amylose starch; the mass concentration of the potato starch suspension is preferably 6%; the centrifugation is preferably at a speed of 4000g for 45min.

[0029] The preparation of the amylose starch paste preferably comprises: mixing the amylose starch with water, and microwave heating to be clear and transparent; the mass-volume ratio of the amylose starch to water is preferably 0.25-1:20g / mL, more preferably 1:20g / mL.

[0030] The preparation of the waxy corn starch paste preferably comprises: mixing the waxy corn starch with water, and heating at 80℃ for 10min; the mass-volume ratio of the waxy corn starch to water is preferably 2-2.75:10g / mL or 3:30g / mL, more preferably 2:10g / mL.

[0031] The standing is preferably placing the cooled and demoulded gel at 4℃ for 36h.

[0032] The application further provides the waxy corn starch gel obtained by the preparation method.

[0033] The technical solutions provided by the application will be described in detail below in combination with the embodiments, but they should not be understood as limiting the protection scope of the application.

[0034] The test materials involved in the embodiments of the application: the waxy corn starch is purchased from Qingdao Haidel Starch Co., Ltd.; the potato starch is purchased from Gansu Blue Sky Potato Industry Development Co., Ltd.; the soluble amylose starch is extracted from potato starch; the glucose oxidase-peroxidase assay kit (K-GLUC) is purchased from Megazyme Co., Ltd. in Ireland; anhydrous ethanol is purchased from National Pharmaceutical Group Chemical Reagent Co., Ltd.; dimethyl sulfoxide is purchased from National Pharmaceutical Group Chemical Reagent Co., Ltd.; and other reagents are all analytical pure.

[0035] The test instruments involved in the embodiments of the present application are as follows: an optical microscope purchased from Nikon Instruments Inc., USA; an S-4800 scanning electron microscope purchased from Hitachi Instruments Service Co., Ltd., Japan; an FTIR Fourier transform infrared spectrometer purchased from Shimadzu Corporation, Japan; an AxSD8 X-ray diffractometer purchased from Bruker AXS GmbH, Germany; a Nano-inXider small-angle X-ray scattering instrument purchased from Xenocs, France; a differential scanning calorimeter purchased from Mettler Toledo International Trade Co., Ltd., USA; a TA.XT Plus C texture analyzer purchased from SMS, UK; an MCR102 interfacial rheometer purchased from Anton Paar, Austria; and an Ultimate3000 high-performance size exclusion chromatograph purchased from Thermo Fisher Scientific, USA.

[0036] All the experiments involved in the embodiments were repeated at least three times. Variance analysis was performed using SPSS version 17 software, and mean comparison was performed using Duncan's test. All the results are reported as mean ± standard deviation, and the difference is judged to be significant when p<0.05.

[0037] Embodiment 1

[0038] (1) Preparation of amylose: a potato starch suspension (6% w / v) was subjected to amylose leaching in a 58°C water bath, and after 1h of leaching, the mixture was centrifuged at 4000g for 15min to separate the supernatant, and the same amount of water was added to the precipitate for 1h of amylose leaching. After 3h of cumulative leaching, the separated supernatants were combined and freeze-dried to obtain amylose powder;

[0039] (2) 1g of amylose obtained in step (1) was added to 20mL of distilled water, and microwave heating was performed until it became clear and transparent to obtain an amylose paste;

[0040] (3) 2g of waxy corn starch was added to 10mL of distilled water, and heating was performed at 80°C for 10min to obtain a waxy corn starch paste;

[0041] (4) The amylose paste and the waxy corn starch paste were uniformly mixed and transferred to a circular mold (diameter 40mm, height 30mm) and placed at 4°C for 36h to obtain a gel.

[0042] Embodiment 2

[0043] Preparation of gels with different proportions of amylose and waxy corn starch

[0044] The mass ratio of amylose starch and waxy corn starch was set as 0g:3g, 0.25g:2.75g, 0.5g:2.5g, 0.75g:2.25g, 1g:2g, respectively, and the preparation method of other steps and Example 1 was the same, and the obtained gels were named as WCS, WCS-8.3%AM, WCS-16.7%AM, WCS-25.0%AM and WCS-33.3%AM, respectively.

[0045] Example 3

[0046] The relevant quality of the gels obtained in Example 2 was detected respectively

[0047] (1) Optical microscope observation of WCS before and after gelatinization

[0048] The morphology of waxy corn starch before and after gelatinization was studied under normal light and cross-polarized light using an optical microscope. The specific operation method was as follows: a small amount of waxy corn starch suspension and waxy corn starch paste containing swollen starch particles were deposited on a clean glass slide with a clean cover glass. The particle morphology was observed under 200x magnification. The specific results are shown in Figure 1

[0049] As can be seen from Figure 1 , the native waxy corn starch shows a round, angular shape, and exhibits a typical Maltese cross under polarized light. After the native waxy corn starch was gelatinized at 80℃ for 10 min, the morphology of the swollen starch particles can be seen (Figure B), however, the Maltese cross of the waxy corn starch disappears after gelatinization. This indicates that the waxy corn starch treated at 80℃ for 10 min has been gelatinized, but still retains residual swollen starch particles.

[0050] (2) Interfacial rheological test of WCS-AM mixed gel

[0051] The mechanical rheometer with strain control was used to determine the rheological properties, which consisted of aluminum parallel plates (diameter 50 mm) and the gap was set to 1 mm. The prepared WCS-based gel was placed on a flat plate at a temperature of 4℃, and the excess gel was removed with a spatula. Then, all the gel samples were stabilized at this temperature for 1 min before measurement. Dynamic rheological experiments evaluated the viscoelastic modulus of the gel samples at a temperature of 4℃ under 1% strain as a function of angular frequency (0.1 rad / s-100 rad / s). The values of the storage modulus (G′), loss modulus (G″), and loss factor (tan δ) of all gel samples were recorded. The specific results are shown in Figure 2

[0052] As can be seen from Figure 2 ​​It can be seen that G' and G" of all samples increased with increasing angular frequency, indicating that all wax maize starch-based gels exhibited typical rheological behavior of weak gels. In addition, G' of all WCS-AM gels was greater than G". From Figure 2 As can be seen in Figure A, dynamic modulus values increased with increasing amylose starch addition. The results indicated that amylose starch enhanced the viscoelasticity of WCS-AM gels, which was due to the interaction of amylose starch with the embedded wax maize starch granules through hydrogen bonds.

[0053] On the other hand, the interaction between amylose starch chains also improved the rheological properties of WCS-AM gels. Tan delta, defined as the ratio of G" to G', reflects the liquid-like or solid-like behavior of the sample. The lower the tan delta, the more solid-like the behavior of the sample. As shown in Figure B, tan delta of all samples was less than 1, indicating that WCS-AM gels exhibited solid-like behavior. In addition, tan delta of WCS-AM mixed gels was lower than that of WCS gels alone, indicating that the network of wax maize starch-based gels changed from more liquid-like to more solid-like when amylose starch was added. Figure 2

[0054] (3) Texture (TPA) test of WCS-AM mixed gels

[0055] The texture properties of WCS and WCS-AM gels were determined using a texture analyzer and a P75 probe. The test parameters were: pre-test, test and post-test speed of 3 mm / s, 1 mm / s, 3 mm / s, and trigger force of 5 g. The specific results are shown in Figure C and Table 1. Figure 3

[0056] Table 1 Texture parameters of WCS and WCS-AM gels

[0057]

[0058] Note: The results are expressed as mean ± standard deviation (SD). Values in the same column with different letters are significantly different (p < 0.05).

[0059] From the results, it can be seen that the addition of amylose starch improved the texture properties of WCS gels, such as hardness, cohesiveness, springiness and gumminess. In addition, the addition of amylose starch also improved the sensory properties of WCS gels, such as color, flavor, taste and overall acceptability. Figure 3 ​​As shown in Table 1, waxy corn starch (10% w / v) exhibited a collapsed gel network after retrogradation at 4°C for 36 h. With increasing amylose addition, the gel morphology gradually became regular and smooth. Compared to WCS gels alone, the addition of amylose significantly improved the gel strength and elasticity of the WCS-AM hybrid gels (p < 0.05). This difference was attributed to the interaction between amylose and the swollen waxy corn starch granules and the enhanced connectivity between amylose molecular chains. Furthermore, cohesion and chewiness are important comprehensive indicators for evaluating gels and are crucial for their practical applications. With increasing amylose addition, both chewiness and cohesion of the WCS-AM hybrid gels increased. Furthermore, the resilience of the WCS-AM hybrid gels also showed a gradual increase with increasing amylose addition. These results demonstrate that amylose plays a crucial role in the formation of strong gels in WCS-based gels containing swollen granules, and that the addition of amylose can effectively modify the texture of waxy corn starch gels.

[0060] (4) Scanning electron microscopy (SEM) observation of WCS-AM hybrid gel

[0061] The microstructure of WCS and WCS-AM gels was obtained using SEM. The prepared gels were freeze-dried. The freeze-dried samples were sliced ​​into thin slices and coated with gold for testing at 5.0 kV. The specific results are shown in Figure 2. Figure 4 shown.

[0062] Depend on Figure 4 It can be seen that the microstructure of the WCS gel shows an uneven "honeycomb" shape and a large pore size. Compared with the WCS gel alone, the addition of amylose can make the network structure of the WCS-AM mixed gel more uniform and tightly ordered. This phenomenon is due to the interaction between AM and the swollen WCS particles affecting the compactness of the gel network structure. In addition, the rearrangement of amylose also helps to strengthen the gel network. When the addition amount of amylose is increased to 25% and 33.3%, some amylose matrix can be seen uniformly and tightly covering the mesh of the WCS gel (yellow dotted line in the figure), indicating that the aggregation of amylose and the interaction between amylose and waxy corn starch occurred during the retrogradation period, which is beneficial to the enhancement of the gel network. Figure 4 The results showed that amylose can effectively stabilize the microstructure of the gel, which helps to reduce the dehydration rate and improve the stability during storage.

[0063] (5) Fourier near infrared (FTIR) determination of WCS-AM hybrid gel

[0064] The WCS and WCS-AM gels were determined by FT-IR at 4000-400 cm -1The spectrum of the prepared gel sheet was measured at 4000-400 cm -1 Scanning within the absorption range with a resolution of 4cm -1 , the number of scans is 32 times. The specific results are as follows Figure 5 shown.

[0065] Depend on Figure 5 It can be seen that at 3600~3000cm -1 A clear peak can be observed at 2800-3000 cm, which is related to the stretching vibration of OH. This result is attributed to the intramolecular and intermolecular hydrogen bonding of water. -1 The peak at 1639cm is due to CH stretching vibration. -1 The peak band at 3600-3000 cm is related to the water content of the sample and corresponds to the OH bending vibration of the bound water in the amorphous region of starch. -1 The broad peaks in the range of 3600-3000 cm-1 are defined as the stretching vibration absorption of the related hydroxyl groups between polymers. -1 The broadening of the peak at 400 nm indicates that the interactions between WCS-AM are enhanced. These interactions occur between adjacent amylose and amylose molecules and between amylose and amylopectin molecules (intermolecular hydrogen bonding), which broadens the wavenumber range of the hydroxyl peak. In addition, compared with the pure WCS gel, the addition of amylose does not show any new peaks, indicating that no new covalent bonds are generated between amylose and the swollen granules of waxy corn starch, which are mainly due to hydrogen bonding. Figure 5 B also shows 1047cm -1 / 1022cm -1 The value of , which is usually used to reflect the short-range ordered structure of the sample. Compared with WCS gel, the addition of amylose increases the -1 / 1022cm -1 The values ​​indicate that amylose can promote the formation of an ordered structure of waxy corn starch, and the packing density of the double helix near the surface of the starch granule becomes increasingly dense during reorientation.

[0066] (6) Small-angle X-ray scattering (SAXS) measurement of WCS-AM hybrid gel

[0067] SAXS experiments were performed using a small-angle X-ray scattering system (λ = 0.154 nm) equipped with two two-dimensional Dectris-Platius3 hybrid pixel detectors operating at 50 kV and 0.6 mA. The moisture content of the samples was adjusted to 60% and then equilibrated at 20 °C overnight. Each sample was scanned four times, with each scan lasting 5 min. The scattering data were recorded and acquired using the IPReader software program associated with the instrument. All data were normalized using NanoinXider's Foxtrot 3.2.7 software for further processing. The specific results are shown in Figure 2. Figure 6 and as shown in Table 2.

[0068] Table 2 SAXS fitting parameters of WCS and WCS-AM gels

[0069]

[0070] Note: Mean ± SD represents three replicates of the experiment; values ​​with different superscript letters within the same column are significantly different (p < 0.05). q: peak position of semicrystalline lamellae; d: average thickness of semicrystalline lamellae calculated by the Woolf-Bragg equation (dBragg = 2π / q); α: fractal geometry index obtained from the slope of the double logSAXS pattern; Dm: mass fractal structure parameter.

[0071] Depend on Figure 6 As can be seen, the scattering intensity of the gel containing amylose is higher than that of the native WCS gel. The scattering intensity depends on the amount of ordered semicrystalline structures and / or the electron density difference between the crystalline and amorphous layers of the amorphous background. The results show that the electron density difference between the ordered and amorphous regions increases with increasing amylose content. The addition of amylose favors the formation of ordered aggregate structures (ordered semicrystalline structures) in the WCS-AM system during retrogradation, resulting in a higher scattering intensity for the WCS-AM hybrid gel than for the WCS gel.

[0072] Depend on Figure 6 As shown in B, both WCS and WCS-AM gels are in the low q region (<0.3nm -1 ) shows a peak. Compared to the WCS gel, the peak position of the WCS-AM hybrid gel shifts from the high-q region to the low-q region with increasing amylose addition, indicating that the size of the ordered structure gradually increases during the retrogradation process. This is attributed to the fact that the addition of amylose strengthens the intermolecular hydrogen bonds in the WCS-AM system, such as the enhanced interactions between amylose and amylose, and between amylose and swollen waxy corn starch particles.

[0073] From Table 2, it can be seen that the thickness of the periodic semicrystalline lamellae is significantly different for the retrograded WCS and WCS-AM gels, with WCS-33.3% AM having the highest d value of 28.358 nm, while WCS has the lowest d value of 19.093 nm. This indicates that the addition of amylose facilitates the rearrangement of ordered aggregates during the retrogradation at 4°C, increasing the thickness of the original ordered semicrystalline lamellae of starch. The exponent a value reflects the surface / mass fractal characteristics of the scattering objects. The mass fractal dimension (1 < a < 3) is an indicator of compactness, while the surface fractal dimension (3 < a < 4) is used to indicate the smoothness of the starch granules.

[0074] The results in Table 2 show that both the WCS and WCS-AM gel samples in the present application are mass fractal, having self-similar structures in nature. The a value of the WCS-AM gel samples is higher than that of the WCS gel samples when amylose is added, which indicates that the addition of amylose forms a more compact structure in the retrograded gel samples. This is mainly due to the enhanced interaction between amylose and the swollen granules of waxy corn starch, which promotes the formation of a three-dimensional network during retrogradation.

[0075] (7) Retrogradation properties (DSC) of WCS-AM mixed gels

[0076] Differential scanning calorimetry was used to study the pasting properties of starch. The samples (3 mg, dry basis) and ultrapure water (6 μΐ) were carefully placed in a crucible and sealed overnight. The crucible was then heated from 25°C to 125°C at a rate of 10°C / min in a nitrogen atmosphere. During the scan, an empty crucible was used as a reference. The onset temperature (To), peak temperature (Tp), end temperature (Tc), and pasting enthalpy change (ΔΗ) were calculated using STARe software. The specific results are shown in Table 3.

[0077] Table 3 Retrogradation properties of WCS and WCS-AM gels

[0078]

[0079]

[0080] Note: Results are expressed as mean ± standard deviation (SD). Values in the same column with different letters are significantly different (p < 0.05). To is the initial temperature, Tp is the peak temperature, Tc is the final temperature, and ΔΗ is the retrogradation enthalpy.

[0081] Table 3 shows that there is no significant difference in the initial and final temperatures between the WCS and WCS-AM gels, but the peak temperature of the WCS-33.3% AM gel increases slightly compared to the WCS gel. This suggests that more complete crystals formed during retrogradation. Furthermore, the enthalpy of retrograded starch indicates that crystallites, composed of bonds between adjacent double helices, melted during storage. The ΔH of the WCS-AM mixed gel sample increased approximately 64-fold compared to the WCS gel, indicating that more crystalline regions formed during retrogradation and that more energy was required to break the crystals. This is attributed to the fact that the addition of amylose promotes interactions between molecular chains in the WCS-AM system, leading to the formation of more crystallites.

[0082] (8) X-ray diffraction (XRD) determination of WCS-AM mixed gel

[0083] The crystalline form of starch samples was measured using an X-ray diffractometer. Before measurement, all samples were placed in a container saturated with relative humidity for 48 hours to achieve a moisture content of >20%. The operating voltage was 40 kV, the current was 25 mA, the scanning range was 4-40° (2θ), and the step size was 0.01. The relative crystallinity was calculated as the ratio of the area of ​​the crystalline region to the total area in the X-ray diffraction pattern. The specific results are as follows Figure 7 and as shown in Table 4.

[0084] Table 4 Relative crystallinity of WCS and WCS-AM gels

[0085]

[0086] Depend on Figure 7 It can be seen that the diffraction peaks of natural waxy corn starch have strong diffraction peaks near 15° and 23°, and there is an unresolved double peak near 17° and 18° of 2θ, indicating that its crystallization mode is type A. Compared with natural waxy corn starch, the peak intensity after gelation has changed significantly, indicating that gelation has severely destroyed the crystal structure of starch. In addition, after the addition of amylose, the diffraction peak positions of all freeze-dried gels have changed, showing a typical B-type X-ray diffraction pattern, and the diffraction peaks are at 2θ values ​​of 5.6°, 15.0°, 17.1°, 22.0°, and 24.0°. This is due to the degradation and recrystallization of amylose and amylopectin. In addition, with the increase in the amount of amylose added, the peak intensity of the WCS-AM mixed freeze-dried gel gradually increases, reflecting the increase in the crystallinity of the freeze-dried gel. Specifically, the RC value of the WCS-AM mixed gel increased from 4.17% for waxy corn starch to 21.04% for WCS-33.3% amylose because the addition of soluble amylose promoted the interaction between the amylose and waxy corn starch molecular chains, which was conducive to the formation of a strong and ordered gel network structure between the starch chains, resulting in an increase in the crystalline area in the gel system.

[0087] The above merely describes the preferred embodiments of the present application, and it should be pointed out that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as falling within the protection scope of the present application.

Claims

1. A process for the preparation of a gel of corn starch, characterized in that, The preparation method comprises the following steps: Mixing straight starch paste and waxy corn starch paste, injection molding, standing, and then obtaining a gel; The mass ratio of straight starch in the straight starch paste to waxy corn starch in the waxy corn starch paste is 1:2-3; The straight starch is potato straight starch; The preparation of the straight starch comprises the following steps: immersing potato starch suspension in a water bath at 58℃ for 1h, centrifuging, repeating the immersion and centrifugation for 2 times, combining the supernatant, freeze-drying, and grinding into powder to obtain the straight starch; The mass concentration of the potato starch suspension is 6%; The preparation of the straight starch paste comprises the following steps: mixing the straight starch with water, and microwave heating until clear and transparent; The mass-volume ratio of the straight starch to water is 0.25-1:20g / mL; The preparation of the waxy corn starch paste comprises the following steps: mixing waxy corn starch with water, and heating at 80℃ for 10min; The mass-volume ratio of the waxy corn starch to water is 2-2.75:10g / mL; The standing is at 4℃.

2. The production method according to claim 1, characterized by, The centrifugation is at a speed of 4000g for 45min.

3. Waxy corn starch gel prepared by the preparation method in any one of claims 1-2.

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