Liquid state simulation system for pectin-sugar interaction and construction method thereof

Abstract

The invention discloses a liquid simulation system of pectin-sugar interaction and a construction method thereof, and the construction method comprises the following steps: adding pectin powder and sugar into a buffer solution to dissolve pectin and sugar in the buffer solution, and then heating for 1-3 hours at the temperature of 60-100 DEG C to obtain the liquid simulation system of pectin-sugar interaction, the ratio of the total mass of the pectin and the sugar to the mass of the buffer solution is (1: 50)-(1: 150), the pH value of the buffer solution is 2.0-6.0, and the mass ratio of the pectin powder to the sugar is (1: 3)-(1: 10). The simulation system can simulate the influence of the hot processing temperature on the interaction of pectin and sugar, and the simulation system is in a liquid state, so that interaction characterization can be carried out more easily by adopting spectrum technologies such as infrared spectrum and the like. The method has the characteristics of convenience and objectivity, and provides a theoretical basis for analyzing the problem that the sugar-pectin interaction influences the quality and structure of the dried product in the hot processing process.

Description

Technical Field

[0001] The invention belongs to the field of food technology, and particularly relates to a liquid simulation system of pectin-sugar interaction and a construction method thereof. Background Art

[0002] Pectin is a natural acidic polymer containing numerous polar groups and a complex structure, playing a crucial role in maintaining the integrity of plant cell walls. Pectin is sensitive to heat, and its structural properties, such as molecular weight distribution, neutral sugar composition, and content, are easily altered during thermal processing, which in turn affects the mechanical properties of the plant cell wall. Sugars regulate flavor and texture, alter moisture distribution in foods, influence processing, improve aroma, increase weight, and reduce production costs. It is widely used in canned foods, preserved fruits, and jams. Studies have shown that the addition of sugars can influence the texture and taste of fruit and vegetable products by altering the structural properties of pectin in the raw cell walls. Therefore, the interaction mechanism between sugars and pectins has attracted increasing research attention. Currently, vacuum freeze-dried solid-state simulation matrices and gel simulation systems are commonly used to investigate the mechanisms of sugar-pectin interactions. Solid-state matrices for vacuum freeze drying are obtained by drying a mixed solution of pectin and any sugar molecules using vacuum freeze drying technology. These matrices exhibit low water content and uniform color and texture. However, these matrices are only suitable for investigating the effects of sugars on the structure of pectin during the freeze-drying process or in freeze-dried foods. Gel systems are formed by adding high-concentration sugars or inducers such as ions to a pectin solution to form a gel, allowing for investigation of the pectin-sugar interaction mechanism. These systems are particularly well-suited for investigating the effects of sugars on pectin structure in jam-like products. However, the processing of preserved fruits and canned foods involves the presence of large amounts of water molecules and the addition of large amounts of exogenous sugars. Therefore, characterizing the mechanisms by which sugars influence pectin conformational changes requires the presence of large amounts of water. Based on this research background, a method for constructing a liquid-state mimic system for investigating pectin-sugar interactions was proposed. Summary of the Invention

[0003] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0004] Another object of the present invention is to provide a method for constructing a liquid simulation system of pectin-sugar interaction. The pectin-sugar liquid simulation system constructed by the present invention is used to explore the interaction mechanism between sugar and pectin during thermal processing.

[0005] Another object of the present invention is to provide a liquid simulation system of pectin-sugar interaction.

[0006] To this end, the technical solution provided by the present invention is: A method for constructing a liquid simulation system of pectin-sugar interaction comprises the following steps: Pectin powder and sugar are added to a buffer solution to dissolve the pectin and sugar in the buffer solution. The pH of the buffer solution is consistent with that of the fruit raw material. The solution is then heated at 60-100°C for 1-3 hours to obtain a liquid simulation system for pectin-sugar interaction. The fruit raw material is the type of fruit from which the pectin powder is produced. For example, if the watermelon pectin powder is derived from watermelon, the fruit raw material in this case is watermelon. The ratio of the total mass of the pectin and sugar to the mass of the buffer solution is 1:50-1:150, the pH of the buffer solution is 2.0-6.0, and the mass ratio of the pectin powder to the sugar is 1:3-1:10.

[0007] Preferably, the method for constructing the liquid simulation system of pectin-sugar interaction further comprises the following steps: First, the pectin sample was precipitated with 75% ethanol by volume for 1-3 hours, and then vacuum filtered. The sample was then washed with anhydrous ethanol for 2-3 times and vacuum filtered to obtain a solid powder sample. Finally, the sample was dried under hot air at 40-50°C to obtain the pectin powder.

[0008] Preferably, in the method for constructing the liquid simulation system of pectin-sugar interaction, the buffer solution includes a disodium hydrogen phosphate-citric acid buffer solution with a pH of 2.0-6.0, a citric acid-sodium citrate buffer solution with a pH of 3.0-6.0, and an acetic acid-sodium acetate buffer solution with a pH of 3.6-5.8.

[0009] Preferably, in the method for constructing the liquid simulation system of pectin-sugar interaction, the sugar is selected from erythritol, glucose, sucrose or trehalose.

[0010] Preferably, in the method for constructing the liquid simulation system of pectin-sugar interaction, the pectin powder is lemon pectin powder, citrus pectin powder, peach pectin powder, tomato pectin powder or watermelon pectin powder.

[0011] Preferably, in the method for constructing the liquid simulation system of pectin-sugar interaction, when the pectin powder is lemon pectin powder or citrus pectin powder, a disodium hydrogen phosphate-citric acid buffer solution with a pH of 2.0 to 6.0 is used, and the ratio of the total mass of the pectin and sugar to the mass of the buffer solution is 1:50 to 1:80.

[0012] Preferably, in the method for constructing the liquid simulation system of pectin-sugar interaction, when the pectin powder is peach pectin powder, a citric acid-sodium citrate buffer solution with a pH of 3.0-6.0 is used, and the ratio of the total mass of the pectin and sugar to the mass of the buffer solution is 1:90-1:120.

[0013] Preferably, in the method for constructing the liquid simulation system of pectin-sugar interaction, when the pectin powder is tomato pectin powder or watermelon pectin powder, an acetic acid-sodium acetate buffer solution with a pH of 3.6 to 5.8 is used, and the ratio of the total mass of the pectin and sugar to the mass of the buffer solution is 1:120 to 1:150.

[0014] The present invention also provides a liquid simulation system of pectin-sugar interaction, which is constructed by the method described above.

[0015] The present invention has at least the following beneficial effects: By selecting a buffer solution and adjusting the pH, the present invention constructs a pectin-sugar liquid simulation system, which can be used to characterize the interaction between pectin and sugars in fruits with a pH range of 2.0 to 5.8. The simulation system can simulate the effect of heat processing temperature on the interaction between pectin and sugars. Furthermore, the liquid nature of the simulation system makes it easier to characterize the interaction using spectroscopic techniques such as infrared spectroscopy. This convenient and objective method provides a theoretical basis for analyzing the impact of sugar-pectin interactions during heat processing on the texture of dried products.

[0016] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The FTIR spectrum of the pectin-sugar simulation system when the buffer solution pH is 3.0 in the embodiment of the present invention is shown.

[0018] Figure 2 The FTIR spectrum of the pectin-sugar simulation system when the buffer solution pH is 3.8 in the embodiment of the present invention is shown.

[0019] Figure 3 The FTIR spectrum of the pectin-sugar simulation system when the buffer solution pH is 4.4 in the embodiment of the present invention is shown. DETAILED DESCRIPTION

[0020] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0021] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.

[0022] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials can be obtained from commercial channels unless otherwise specified.

[0023] A method for constructing a liquid simulation system of pectin-sugar interaction comprises the following steps: Step 1: After the pectin sample is precipitated with 75% ethanol by volume for 1-3 hours, vacuum filtration is performed to obtain a solid powder; Step 2: The sample obtained in the first step is further washed with anhydrous ethanol (99% by volume) for 2-3 times and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40-50°C hot air drying conditions to obtain pectin powder.

[0024] Step 4: Prepare acidic buffer solution. Use disodium hydrogen phosphate-citric acid buffer solution (pH 2.0-6.0) or citric acid-sodium citrate buffer solution (pH 3.0-6.0) or acetic acid-sodium acetate buffer solution (pH 3.6-5.8) Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 2.0-5.8 according to the pH of the actual fruit raw materials. Step 6: Slowly add pectin and sugar (mass ratio 1:3-1:10) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of buffer solution is 1:50-1:150; Step 7: Continue stirring the solution obtained in step 6 until the pectin and sugar are fully dissolved.

[0025] Step 8: Heat treatment. (The temperature can be adjusted according to the actual processing temperature of the product.) Heat the simulated system obtained in step 7 at 60-100°C for 1-3 hours to obtain a simulated system.

[0026] In order to enable those skilled in the art to better understand the technical solution of the present invention, the following examples are provided for further explanation: Example I-1 (lemon pectin + erythritol) Step 1: After the lemon pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain lemon pectin powder.

[0027] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 2.0 according to the pH of the actual lemon raw material; Step 6: Slowly add lemon pectin (1 g) and erythritol (4 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:50; Step 7: Stir the solution obtained in step 6 continuously until the lemon pectin and sugar are fully dissolved.

[0028] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 60° C. for 2 h to obtain a simulation system.

[0029] Example I-2 (lemon pectin + glucose) Step 1: After the lemon pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain lemon pectin powder.

[0030] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 2.0 according to the pH of the actual lemon raw material; Step 6: Slowly add lemon pectin (1 g) and glucose (6 g) to the solution obtained in step 5, wherein the total mass ratio of pectin and sugar to the mass of the buffer solution is set to 1:70; Step 7: Stir the solution obtained in step 6 continuously until the lemon pectin and sugar are fully dissolved.

[0031] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 70° C. for 3 h to obtain a simulation system.

[0032] Example I-3 (lemon pectin + sucrose) Step 1: After the lemon pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain lemon pectin powder.

[0033] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 2.0 according to the pH of the actual lemon raw material; Step 6: Slowly add lemon pectin (1 g) and sucrose (5 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:80; Step 7: Stir the solution obtained in step 6 continuously until the lemon pectin and sugar are fully dissolved.

[0034] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 80° C. for 2 h to obtain a simulation system.

[0035] Example I-4 (lemon pectin + trehalose) Step 1: After the lemon pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain lemon pectin powder.

[0036] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 2.0 according to the pH of the actual lemon raw material; Step 6: Slowly add lemon pectin (1 g) and trehalose (7 g) to the solution obtained in step 5, wherein the total mass ratio of pectin and sugar to the mass of buffer solution is set to 1:70; Step 7: Stir the solution obtained in step 6 continuously until the lemon pectin and sugar are fully dissolved.

[0037] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 75° C. for 3 h to obtain a simulation system.

[0038] Example II-1 (Citrus Pectin + Erythritol) (Comparison of Fourier Transform Infrared Spectra with Pure Pectin in Comparative Example 1) Step 1: After the citrus pectin sample was precipitated with 75% ethanol by volume for 1 hour, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed twice with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain citrus pectin powder.

[0039] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.0 according to the pH of the actual citrus fruit. Step 6: Slowly add citrus pectin (1 g) and erythritol (5 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:50; Step 7: Continue stirring the solution obtained in step 6 until the citrus pectin and sugar are fully dissolved.

[0040] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 90° C. for 2 h to obtain a simulation system.

[0041] Example II-2 (Citrus Pectin + Glucose) (Comparison of Fourier Transform Infrared Spectra with Pure Pectin in Comparative Example 1) Step 1: After the citrus pectin sample was precipitated with 75% ethanol by volume for 1 hour, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed twice with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain citrus pectin powder.

[0042] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.0 according to the pH of the actual citrus raw materials; Step 6: Slowly add citrus pectin (1 g) and glucose (6 g) to the solution obtained in step 5, wherein the total mass ratio of pectin and glucose to the mass of the buffer solution is set to 1:60; Step 7: Continue stirring the solution obtained in step 6 until the citrus pectin and sugar are fully dissolved.

[0043] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 70° C. for 2 h to obtain a simulation system.

[0044] Example II-3 (Citrus Pectin + Sucrose) (Comparison of Fourier Transform Infrared Spectra of Pure Pectin with Comparative Example 1) Step 1: After the citrus pectin sample was precipitated with 75% ethanol by volume for 1 hour, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed twice with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain citrus pectin powder.

[0045] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.0 according to the pH of the actual citrus raw materials; Step 6: Slowly add citrus pectin (1 g) and sucrose (4 g) to the solution obtained in step 5, wherein the total mass ratio of citrus pectin and sugar to the mass of the buffer solution is set to 1:50; Step 7: Continue stirring the solution obtained in step 6 until the citrus pectin and sugar are fully dissolved.

[0046] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 60° C. for 2 h to obtain a simulation system.

[0047] Example II-4 (Citrus Pectin + Trehalose) (Comparison of Fourier Transform Infrared Spectra with Pure Pectin in Comparative Example 1) Step 1: After the citrus pectin sample was precipitated with 75% ethanol by volume for 1 hour, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed twice with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain citrus pectin powder.

[0048] Step 4: Preparation of acidic buffer solution. Use disodium hydrogen phosphate-citric acid to prepare buffer solution (pH 2.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.0 according to the pH of the actual citrus raw materials; Step 6: Slowly add citrus pectin (1 g) and trehalose (8 g) to the solution obtained in step 5, wherein the total mass ratio of pectin and sugar to the mass of the buffer solution is set to 1:80; Step 7: Continue stirring the solution obtained in step 6 until the citrus pectin and sugar are fully dissolved.

[0049] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 80° C. for 2 h to obtain a simulation system.

[0050] Example III-1 (Peach Pectin + Sucrose) - Simulating the Thermal Processing of Preserved Fruit Step 1: After the peach pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain peach pectin powder.

[0051] Step 4: Prepare acidic buffer solution. Use citric acid-sodium citrate to prepare buffer solution (pH 3.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.8 according to the actual pH of the peach raw material. Step 6: Slowly add peach pectin (1 g) and sucrose (6 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:90; Step 7: Continue stirring the solution obtained in step 6 until the peach pectin and sugar are fully dissolved.

[0052] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 70° C. for 3 h to obtain a simulation system.

[0053] Example III-2 (Peach Pectin + Erythritol) - Simulating the Thermal Processing of Preserved Fruit Step 1: After the peach pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain peach pectin powder.

[0054] Step 4: Prepare acidic buffer solution. Use citric acid-sodium citrate to prepare buffer solution (pH 3.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.8 according to the actual pH of the peach raw material. Step 6: Slowly add peach pectin (1 g) and erythritol (3 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:90; Step 7: Continue stirring the solution obtained in step 6 until the peach pectin and sugar are fully dissolved.

[0055] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 80° C. for 3 h to obtain a simulation system.

[0056] Example III-3 (Peach Pectin + Glucose) - Simulating the Thermal Processing of Preserved Fruit Step 1: After the peach pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain peach pectin powder.

[0057] Step 4: Prepare acidic buffer solution. Use citric acid-sodium citrate to prepare buffer solution (pH 3.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.8 according to the actual pH of the peach raw material. Step 6: Slowly add peach pectin (1 g) and glucose (8 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:110; Step 7: Continue stirring the solution obtained in step 6 until the peach pectin and sugar are fully dissolved.

[0058] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 80° C. for 3 h to obtain a simulation system.

[0059] Example II-4 (Peach Pectin + Trehalose) - Simulating the Thermal Processing of Preserved Fruit Step 1: After the peach pectin sample was precipitated with 75% ethanol for 2 hours, vacuum filtration was performed to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain peach pectin powder.

[0060] Step 4: Prepare acidic buffer solution. Use citric acid-sodium citrate to prepare buffer solution (pH 3.0-6.0); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 3.8 according to the actual pH of the peach raw material. Step 6: Slowly add peach pectin (1 g) and trehalose (10 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:120; Step 7: Continue stirring the solution obtained in step 6 until the peach pectin and sugar are fully dissolved.

[0061] Step 8: Heat treatment: The simulation system obtained in step 7 is heated at 100° C. for 3 h to obtain a simulation system.

[0062] Example IV-1 (Tomato Pectin + Erythritol) Step 1: The tomato pectin sample was precipitated with 75% ethanol for 2 h, and then vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain tomato pectin powder.

[0063] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 4.4 according to the pH of the actual tomato raw material. Step 6: Slowly add tomato pectin (1 g) and erythritol (5 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:120; Step 7: Continue stirring the solution obtained in step 6 until the tomato pectin and sugar are fully dissolved.

[0064] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 60° C. for 2 h to obtain a simulation system.

[0065] Example IV-2 (Tomato Pectin + Glucose) Step 1: The tomato pectin sample was precipitated with 75% ethanol for 2 h, and then vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain tomato pectin powder.

[0066] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 4.4 according to the pH of the actual tomato raw material. Step 6: Slowly add tomato pectin (1 g) and glucose (8 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:140; Step 7: Continue stirring the solution obtained in step 6 until the tomato pectin and sugar are fully dissolved.

[0067] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 70° C. for 2 h to obtain a simulation system.

[0068] Example IV-3 (Tomato Pectin + Sucrose) Step 1: The tomato pectin sample was precipitated with 75% ethanol for 2 h, and then vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain tomato pectin powder.

[0069] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 4.4 according to the pH of the actual tomato raw material. Step 6: Slowly add tomato pectin (1 g) and sucrose (6 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:130; Step 7: Continue stirring the solution obtained in step 6 until the tomato pectin and sugar are fully dissolved.

[0070] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 80°C for 1 hour to obtain a simulation system.

[0071] Example IV-4 (Tomato Pectin + Trehalose) Step 1: The tomato pectin sample was precipitated with 75% ethanol for 2 h, and then vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 45°C hot air drying conditions to obtain tomato pectin powder.

[0072] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 4.4 according to the pH of the actual tomato raw material. Step 6: Slowly add tomato pectin (1 g) and trehalose (9 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:140; Step 7: Continue stirring the solution obtained in step 6 until the tomato pectin and sugar are fully dissolved.

[0073] Step 8: Heat treatment: The simulation system obtained in step 7 is heated at 100° C. for 1 h to obtain a simulation system.

[0074] Example V-1 (Watermelon Pectin + Erythritol) Step 1: After the watermelon pectin sample was precipitated with 75% ethanol for 2 h, it was vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain watermelon pectin powder.

[0075] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 5.8 according to the pH of the actual watermelon raw material. Step 6: Slowly add watermelon pectin (1 g) and erythritol (7 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:130; Step 7: Continue stirring the solution obtained in step 6 until the watermelon pectin and sugar are fully dissolved.

[0076] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 60° C. for 3 h to obtain a simulation system.

[0077] Example V-2 (Watermelon Pectin + Glucose) Step 1: After the watermelon pectin sample was precipitated with 75% ethanol for 2 h, it was vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain watermelon pectin powder.

[0078] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 5.8 according to the pH of the actual watermelon raw material; Step 6: Slowly add watermelon pectin (1 g) and glucose (5 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:120; Step 7: Continue stirring the solution obtained in step 6 until the watermelon pectin and sugar are fully dissolved.

[0079] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 80° C. for 2 h to obtain a simulation system.

[0080] Example V-3 (watermelon pectin + sucrose) Step 1: After the watermelon pectin sample was precipitated with 75% ethanol for 2 h, it was vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain watermelon pectin powder.

[0081] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 5.8 according to the pH of the actual watermelon raw material; Step 6: Slowly add watermelon pectin (1 g) and sucrose (10 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:140; Step 7: Continue stirring the solution obtained in step 6 until the watermelon pectin and sugar are fully dissolved.

[0082] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 80° C. for 2 h to obtain a simulation system.

[0083] Example V-4 (watermelon pectin + trehalose) Step 1: After the watermelon pectin sample was precipitated with 75% ethanol for 2 h, it was vacuum filtered to obtain a solid powder; Step 2: The sample obtained in the first step was washed three times with anhydrous ethanol (99% by volume) and vacuum filtered to obtain a solid powder; Step 3: The sample obtained in the second step is placed under 40°C hot air drying conditions to obtain watermelon pectin powder.

[0084] Step 4: Prepare acidic buffer solution. Use acetic acid-sodium acetate to prepare buffer solution (pH 3.6-5.8); Step 5: Adjust pH. The pH of the simulated system obtained in step 4 can be adjusted to 5.8 according to the pH of the actual watermelon raw material; Step 6: Slowly add watermelon pectin (1 g) and trehalose (9 g) to the solution obtained in step 5, wherein the ratio of the total mass of pectin and sugar to the mass of the buffer solution is set to 1:140; Step 7: Continue stirring the solution obtained in step 6 until the watermelon pectin and sugar are fully dissolved.

[0085] Step 8: Heat treatment: The simulation system obtained in step 7 was heated at 90° C. for 1 h to obtain a simulation system.

[0086] Depend on Figure 1 、 Figure 2 and Figure 3 It can be seen that under different pH conditions, there are obvious differences in the FT-IR scanning spectra, especially in the range of 2700-3750 cm -1 and 750-1200cm -1 In the wavelength range, it is shown that there is an interaction between pectin and sugar. In summary, the pectin-sugar liquid simulation system constructed by the present invention can be used to explore the interaction between pectin and sugar, and the Fourier infrared scanning technology can be used to reveal the interaction mechanism between the two.

[0087] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and embodiments. They can be applied to a variety of fields suitable for the embodiments of the present invention. Those skilled in the art will readily realize further modifications. Therefore, without departing from the general concept defined by the claims and their equivalents, the embodiments of the present invention are not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for constructing a liquid simulation system of pectin-sugar interaction, characterized in that: The steps include: Pectin powder and sugar are added to a buffer solution to dissolve the pectin and sugar in the buffer solution, the pH of the buffer solution is consistent with the pH of the fruit raw material, and then heated at a temperature of 60-100° C. for 1-3 hours to obtain a liquid simulation system of pectin-sugar interaction, wherein the fruit raw material is the fruit type for producing the pectin powder; The ratio of the total mass of the pectin and the sugar to the mass of the buffer solution is 1:50-1:150, the pH of the buffer solution is 2.0-6.0, and the mass ratio of the pectin powder to the sugar is 1:3-1:

10.

2. The method for constructing a liquid simulation system of pectin-sugar interaction according to claim 1, characterized in that: The following steps are also included: First, the pectin sample is precipitated with 75% ethanol by volume for 1-3 hours, and then vacuum filtered. Then, it is washed with anhydrous ethanol for 2-3 times, and vacuum filtered to obtain a solid powder sample. Finally, it is placed under hot air drying conditions at a temperature of 40-50°C to obtain the pectin powder.

3. The method for constructing a liquid simulation system of pectin-sugar interaction according to claim 1, characterized in that: The buffer solution includes a disodium hydrogen phosphate-citric acid buffer solution with a pH of 2.0-6.0, a citric acid-sodium citrate buffer solution with a pH of 3.0-6.0, and an acetic acid-sodium acetate buffer solution with a pH of 3.6-5.

8.

4. The method for constructing a liquid simulation system of pectin-sugar interaction according to claim 1, characterized in that: The sugar is selected from erythritol, glucose, sucrose or trehalose.

5. The method for constructing a liquid simulation system of pectin-sugar interaction according to claim 1, characterized in that: The pectin powder is lemon pectin powder, citrus pectin powder, peach pectin powder, tomato pectin powder or watermelon pectin powder.

6. The method for constructing a liquid simulation system of pectin-sugar interaction according to claim 5, characterized in that: When the pectin powder is lemon pectin powder or citrus pectin powder, a disodium hydrogen phosphate-citric acid buffer solution with a pH of 2.0-6.0 is used.

7. The method for constructing a liquid simulation system of pectin-sugar interaction according to claim 5, characterized in that: When the pectin powder is peach pectin powder, a citric acid-sodium citrate buffer solution with a pH of 3.0-6.0 is used.

8. The method for constructing a liquid simulation system of pectin-sugar interaction according to claim 5, characterized in that: When the pectin powder is tomato pectin powder or watermelon pectin powder, an acetic acid-sodium acetate buffer solution with a pH of 3.6-5.8 is used.

9. A liquid simulation system of pectin-sugar interaction, characterized in that: The method is constructed by the method described in claim 1.

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