A zero-calorie dietary fiber-enriched sweetener and a method for preparing the same

Abstract

This invention discloses a zero-calorie sugar rich in dietary fiber and its preparation method, belonging to the field of zero-calorie sugar technology. The method includes the following steps: enzymatic hydrolysis of a mixture of inulin and resistant dextrin using inulinase and transglucosidase to obtain material A; adding dried dragon fruit peel powder to deionized water, heating and stirring evenly in a water bath, adjusting the pH of the system to 4.0-5.0, and enzymatic hydrolysis using pectin methyl esterase, xylanase, and polygalacturonase to obtain material B; mixing erythritol, mogroside V, steviol glycosides, sucralose, material A, and material B evenly to obtain a zero-calorie sugar base powder; dissolving γ-cyclodextrin in deionized water, adding anhydrous ethanol, and stirring evenly to obtain a binder; feeding the zero-calorie sugar base powder into a fluidized bed granulator, atomizing and spraying the binder, fluidizing and drying, and sieving to obtain a scientifically formulated, technologically stable, flavorful, and nutritionally healthy zero-calorie sugar rich in dietary fiber.

Description

Technical Field

[0001] This invention belongs to the field of zero-calorie sugar technology, specifically relating to a zero-calorie sugar rich in dietary fiber and its preparation method. Background Technology

[0002] With the comprehensive upgrading of national health consumption awareness, sugar control, fat reduction, and intestinal health have become core demands in food consumption. Long-term excessive intake of traditional added sugars such as sucrose and fructose is a significant contributing factor to various metabolic diseases, including obesity, hyperglycemia, hyperlipidemia, and tooth decay. The drawbacks of traditional sugars—high calories and a high glycemic index—are becoming increasingly prominent, making them unsuitable for the healthy dietary needs of modern consumers. Against this backdrop, zero-calorie sugar substitutes, with their advantages of being calorie-free, not raising blood sugar, and having a wide range of sweetness levels, are gradually replacing traditional sucrose and are widely used in beverages, baking, snack foods, and daily seasonings, leading to a continuous increase in market demand.

[0003] Currently, most mainstream zero-calorie sugar products on the market use single or compound sweeteners such as erythritol, steviol glycosides, sucralose, and xylitol as core ingredients. While they can achieve a zero-calorie, zero-glycemic index sweetness substitution effect, their functionality is relatively limited, only meeting basic sweetness needs and exhibiting significant technological shortcomings. Firstly, existing zero-calorie sugars only provide sweetness without additional nutritional benefits, failing to meet consumers' diverse health needs for sugar reduction, nutritional supplementation, and gut health, resulting in low added value. Secondly, most artificially synthesized or single-natural zero-calorie sugars have taste defects; some products have a bitter taste, lingering aftertaste, and poor sweetness stability, affecting the taste and overall experience. Thirdly, conventional zero-calorie sugars lack the physiological activity of dietary fiber, failing to regulate the balance of intestinal flora or promote intestinal peristalsis; long-term consumption only avoids the harmful effects of sugar and cannot provide dietary nutritional supplementation.

[0004] Dietary fiber is the seventh essential nutrient for the human body. It is divided into soluble and insoluble dietary fiber, and possesses multiple benefits such as low calorie content, resistance to digestion, promotion of intestinal metabolism, increased satiety, and stable postprandial blood sugar. It can effectively improve problems such as insufficient dietary fiber intake, intestinal dysfunction, and slow metabolism caused by refined diets in modern populations. Currently, some food products have attempted to add dietary fiber to upgrade their functionality. However, the combined application of dietary fiber and zero-calorie sugar still faces many technical bottlenecks. Most products simply physically mix dietary fiber with sweeteners, resulting in poor mixing uniformity, low dietary fiber content, easy clumping, poor solubility, and insufficient stability. This leads to products that easily separate when brewed, have a rough texture, and fail to achieve both a sweet taste and high fiber content. Furthermore, conventional compounding processes easily destroy the activity of dietary fiber and make it difficult to achieve the dual standards of zero calories and high dietary fiber content.

[0005] In conclusion, developing a scientifically formulated, technologically stable, and flavor-enhanced zero-calorie sugar rich in dietary fiber to meet the public's healthy dietary needs has significant market value and research significance. Summary of the Invention

[0006] The purpose of this invention is to provide a zero-calorie sugar rich in dietary fiber and its preparation method. By optimizing the preparation method and product formulation, a zero-calorie sugar rich in dietary fiber with stable processing and improved flavor is obtained to meet the public's healthy dietary needs.

[0007] The objective of this invention can be achieved through the following technical solutions: A method for preparing a zero-calorie sugar rich in dietary fiber includes the following steps: S1. The first complex enzyme preparation, composed of inulinase and transglucosidase, is used to enzymatically hydrolyze the mixture of inulin and resistant dextrin to obtain material A; S2. Add the dried dragon fruit peel powder to deionized water, heat in a water bath and stir evenly. Adjust the pH of the system to 4.0-5.0, and enzymatically hydrolyze it at 45-50℃ using a second complex enzyme preparation composed of pectin methyl esterase, xylanase and polygalacturonase to obtain material B. S3. Take erythritol, mogroside V, steviol glycoside, sucralose, material A and material B and mix them evenly to obtain zero-calorie sugar-based powder; S4. Dissolve γ-cyclodextrin in deionized water, add anhydrous ethanol, stir well to obtain the adhesive; S5. The zero-calorie sugar base powder is fed into a fluidized bed granulator, atomized and sprayed into the binder, fluidized and dried, and sieved to obtain the zero-calorie sugar rich in dietary fiber.

[0008] As a preferred embodiment of the present invention, in step S1, the mass ratio of inulinase to transglucosidase is 3-5:1-2.

[0009] As a preferred embodiment of the present invention, in step S1, the mass ratio of inulin, resistant dextrin, and complex enzyme is 4-6:1-2:0.06-0.07.

[0010] As a preferred embodiment of the present invention, in step S2, the mass ratio of pectin methylesterase, xylanase and polygalacturonase is 2-3:0.5-1:0.1-0.3.

[0011] As a preferred technical solution of the present invention, in step S2, the ratio of the dried dragon fruit peel powder, deionized water, and the second compound enzyme preparation is 1g: 15-25mL: 0.008-0.012g.

[0012] As a preferred embodiment of the present invention, in step S3, the mass ratio of erythritol, mogroside V, steviol glycoside, sucralose, material A and material B is 400-480: 0.4-0.5: 0.1-0.2: 0.05-0.1: 180-240: 30-60.

[0013] As a preferred embodiment of the present invention, in step S4, the mass ratio of γ-cyclodextrin, deionized water and anhydrous ethanol is 80-100:100-120:20-30.

[0014] As a preferred embodiment of the present invention, in step S5, the mass ratio of the zero-calorie sugar base powder to the binder is 8-10:0.6-0.8.

[0015] Another objective of this invention is to provide a zero-calorie sugar rich in dietary fiber, which is prepared using the above-described method for preparing a zero-calorie sugar rich in dietary fiber.

[0016] The beneficial effects of this invention are: (1) The present invention discloses a zero-calorie sugar rich in dietary fiber and its preparation method by setting up a two-stage exclusive compound enzymatic hydrolysis process: inulin and resistant dextrin are modified by using a compound system of inulinase and transglucosidase to degrade the macromolecular polysaccharide into highly water-soluble dietary fiber fragments; at the same time, a compound system of pectin methyl esterase, xylanase and polygalacturonase is used to deeply enzymatically hydrolyze the dragon fruit peel raw material, effectively degrading impurities such as insoluble pectin and lignin, and completely removing the green and bitter taste of the dragon fruit peel to obtain pectin oligosaccharide dietary fiber. The enzymatically modified dual dietary fiber system retains the total fiber content while significantly increasing the proportion of dietary fiber available to the human body. This is more conducive to regulating intestinal metabolism, enhancing satiety, and strengthening the product's health attributes. It also improves the product's cold water solubility, enabling its use in multiple application scenarios. The enzymatically modified dietary fiber exhibits better dispersibility and higher powder uniformity. Combined with the subsequent cyclodextrin granulation system, it results in higher particle formation rate and improved powder fineness. At the same time, it avoids the problems of large molecular fiber's easy moisture absorption and agglomeration, further optimizing the product's storage stability. Based on zero calories, no glycemic index, and no calorie burden, the product's dietary fiber content is significantly increased, which can effectively supplement the deficiencies in the human body's daily diet, regulate the balance of intestinal flora, promote intestinal peristalsis, and enhance satiety. This solves the problems of slow metabolism and intestinal dysfunction caused by traditional refined diets, enhancing the product's added value and health attributes.

[0017] (2) The dietary fiber-rich zero-calorie sugar and its preparation method disclosed in this invention use a special adhesive system composed of γ-cyclodextrin, deionized water and anhydrous ethanol. γ-cyclodextrin has excellent molecular coating, bonding and molding and moisture-proof and moisture-resistant properties. During fluidized granulation, it can make the powder uniformly agglomerate and form, with high particle regularity and low fine powder content. At the same time, it can form a dense protective film on the particle surface, effectively isolate environmental moisture, significantly inhibit the powder from absorbing moisture and agglomerating, and solve the problems of conventional zero-calorie sugar being easy to absorb moisture, easy to agglomerate and short storage period.

[0018] (3) This invention uses erythritol, mogroside V, steviol glycosides, and sucralose to construct a multi-component sweetness system, which forms a significant synergistic mechanism with water-soluble dietary fiber fragments and pectin oligosaccharides prepared by two-stage enzymatic hydrolysis: the modified dietary fiber, with its network molecular structure, adsorbs and coats the bitter aftertaste and metallic odor of steviol glycosides and sucralose through hydrogen bonding and hydrophobic interaction, thus purifying the sweetness; at the same time, it forms a slow-release complexation effect on the sweet substances, releasing the sweetness evenly and prolonging the aftertaste, making the sweetness round and close to sucrose; at the same time, the modified dietary fiber can act as a sweetener dispersion carrier, improving the uniformity of the powder and its solubility in cold water, and inhibiting particle agglomeration and moisture absorption; both the sweetness compound system and the modified dietary fiber have the characteristics of being low in calories and zero in blood sugar, and the combined effects of pectin oligosaccharides and water-soluble dietary fiber on intestinal health and peristalsis promotion achieve multiple synergistic effects on taste, flavor, physicochemical properties and health functions. Detailed Implementation

[0019] The claims of the present invention will be further described in detail below with reference to specific embodiments, but this does not constitute any limitation on the present invention. Any limited modifications made by any person within the scope of protection of the claims of the present invention are still within the scope of protection of the claims of the present invention.

[0020] The sources of some of the raw materials for this invention are as follows: Inulinase, Hebei Runbu Biotechnology Co., Ltd.; Transglucosidase, CAS No. 9001-42-7, Shanghai Chunshi Biotechnology Co., Ltd.; Pectin methylesterase, CAS No. 9025-98-3, Guangdong Wengjiang Chemical Reagent Co., Ltd.; Xylanase, Hefei Shengrun Biological Products Co., Ltd.; Polygalacturonase, Shanghai Aladdin Biochemical Technology Co., Ltd.; Erythritol, Jiangsu Caiwei Biotechnology Co., Ltd.; Mogroside V, CAS No. 88901-36-4, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0021] Example 1

[0022] Inulin and resistant dextrin were mixed and added to deionized water. The mixture was heated and stirred in a water bath at 65°C for 30 min. The pH of the system was adjusted to 5.2 using a 0.1 mol / L citrate-sodium citrate buffer solution. The mixture was then cooled to 55°C, and the first compound enzyme preparation was added. The mixture was kept warm and stirred at 100 rpm for 1.5 h. The enzyme was then inactivated at 90°C for 10 min. The mixture was then freeze-dried at -20°C under vacuum of 10 Pa for 3 h. The resulting material A was obtained by pulverizing the mixture through an 80-mesh sieve. The mass ratio of inulin, resistant dextrin, deionized water, and compound enzyme was 4:1:80:0.06. The first compound enzyme preparation consisted of inulinase and transglucosidase in a mass ratio of 3:1. Fresh dragon fruit peel was taken, washed and cleaned, cut into pieces, and dried at 40℃ to constant weight. The dried peel was then pulverized and passed through a 60-mesh sieve to obtain dragon fruit peel powder. The powder was added to deionized water and stirred in a 55℃ water bath for 30 minutes. The pH of the system was adjusted to 4.0 using a 0.1 mol / L citrate-sodium citrate buffer solution. The temperature was lowered to 45℃, and the second complex enzyme preparation was added. The mixture was incubated and stirred for 2 hours for enzymatic hydrolysis. The temperature was then raised to 95℃ for 10 minutes to inactivate the enzyme. The mixture was cooled to room temperature and centrifuged at 3000 rpm for 10 minutes. min, collect the supernatant, add 75% ethanol aqueous solution, let stand at 4℃ for 8h to precipitate, filter, collect solid phase vacuum concentration, freeze dry at vacuum degree 10Pa and -15℃ for 8h, pulverize and pass through an 80-mesh sieve to obtain material B; the second compound enzyme preparation is composed of pectin methyl esterase, xylanase and polygalacturonase in a mass ratio of 2:0.5:0.1; the ratio of the dried dragon fruit peel powder, deionized water and the second compound enzyme preparation is 1g:15mL:0.008g; Erythritol, mogroside V, steviol glycosides, sucralose, material A, and material B were added to a double cone mixer and mixed at 60 r / min for 15 min under the conditions of relative humidity RH≤45% and temperature 20℃ to obtain zero-calorie glycosyl powder; the mass ratio of erythritol, mogroside V, steviol glycosides, sucralose, material A, and material B was 400:0.4:0.1:0.05:180:30. γ-Cyclodextrin was dissolved in deionized water under water bath heating and stirring at 60°C. After cooling to 40°C, anhydrous ethanol was added and stirred evenly to obtain a binder. The mass ratio of γ-Cyclodextrin, deionized water and anhydrous ethanol was 80:100:20. Zero-calorie sugar base powder is fed into a fluidized bed granulator. The inlet air temperature is set to 50°C and the outlet air temperature to 35°C. The binder is atomized and sprayed while the material is tumbling. The atomization pressure is controlled at 0.20 MPa and the spray rate is 8 g / min. The spraying is stopped and the liquid is fluidized and dried at 60°C until the moisture content is ≤3.0%. The liquid is then passed through a 60-mesh sieve to obtain the zero-calorie sugar rich in dietary fiber. The mass ratio of the zero-calorie sugar base powder to the binder is 8:0.6.

[0023] Example 2

[0024] Inulin and resistant dextrin were mixed and added to deionized water. The mixture was heated and stirred in a water bath at 65°C for 35 min. The pH of the system was adjusted to 5.6 using 0.1 mol / L citrate-sodium citrate buffer solution. The mixture was then cooled to 58°C, and the first compound enzyme preparation was added. The mixture was kept warm and stirred at 150 rpm for 2.0 h. The enzyme was then inactivated at 90°C for 10 min. The mixture was then freeze-dried at -20°C under vacuum of 10 Pa for 4 h. The resulting material A was obtained by pulverizing the mixture through an 80-mesh sieve. The mass ratio of inulin, resistant dextrin, deionized water, and compound enzyme was 5:1.5:80:0.065. The first compound enzyme preparation consisted of inulinase and transglucosidase in a mass ratio of 4:1.5. Fresh dragon fruit peel was collected, washed to remove impurities, cut into pieces, and dried at 45℃ to constant weight. The dried peel was then pulverized and passed through an 80-mesh sieve to obtain dragon fruit peel powder. The powder was added to deionized water and stirred in a 60℃ water bath for 35 minutes. The pH of the system was adjusted to 4.5 using a 0.1 mol / L citrate-sodium citrate buffer solution. The temperature was lowered to 48℃, and the second complex enzyme preparation was added. The mixture was incubated and stirred for 3 hours for enzymatic hydrolysis. The temperature was then raised to 95℃ for 10 minutes to inactivate the enzyme. The mixture was cooled to room temperature and centrifuged at 4000 rpm for 15 minutes. The supernatant was collected, and an 80% (v / v) ethanol aqueous solution was added. The mixture was allowed to stand at 4°C for 9 hours to precipitate. After filtration, the solid phase was collected and concentrated under reduced pressure. The mixture was then freeze-dried at -20°C under a vacuum of 10 Pa for 9 hours and pulverized through an 80-mesh sieve to obtain material B. The second compound enzyme preparation is composed of pectin methyl esterase, xylanase, and polygalacturonase in a mass ratio of 2.5:0.8:0.2. The ratio of the dried dragon fruit peel powder, deionized water, and the second compound enzyme preparation is 1 g:20 mL:0.010 g. Erythritol, mogroside V, steviol glycosides, sucralose, material A, and material B were added to a double cone mixer and mixed at 70 r / min for 20 min under the conditions of relative humidity RH≤45% and temperature 23℃ to obtain zero-calorie glycosyl powder; the mass ratio of erythritol, mogroside V, steviol glycosides, sucralose, material A, and material B was 460:0.48:0.15:0.07:220:50. γ-Cyclodextrin was dissolved in deionized water under water bath heating and stirring at 60°C. After cooling to 40°C, anhydrous ethanol was added and stirred evenly to obtain a binder. The mass ratio of γ-Cyclodextrin, deionized water and anhydrous ethanol was 90:110:25. Zero-calorie sugar base powder is fed into a fluidized bed granulator. The inlet air temperature is set to 55°C and the outlet air temperature to 38°C. Under the condition of material tumbling, the binder is atomized and sprayed. The atomization pressure is controlled at 0.22MPa and the spray rate is 9g / min. The spraying is stopped and the liquid is fluidized and dried at 60°C until the moisture content is ≤3.0%. The liquid is then passed through a 70-mesh sieve to obtain the zero-calorie sugar rich in dietary fiber. The mass ratio of the zero-calorie sugar base powder to the binder is 9:0.7.

[0025] Example 3

[0026] Inulin and resistant dextrin were mixed and added to deionized water. The mixture was heated and stirred in a water bath at 65°C for 40 min. The pH of the system was adjusted to 5.7 using a 0.1 mol / L citrate-sodium citrate buffer solution. The temperature was lowered to 60°C, and the first compound enzyme preparation was added. The mixture was kept warm and stirred at 200 rpm for 2.5 h. The temperature was raised to 90°C to inactivate the enzyme for 10 min. The mixture was then freeze-dried at -20°C under vacuum of 10 Pa for 5 h. The material A was obtained by pulverizing the mixture through an 80-mesh sieve. The mass ratio of inulin, resistant dextrin, deionized water, and compound enzyme was 6:2:80:0.07. The first compound enzyme preparation consisted of inulinase and transglucosidase in a mass ratio of 5:2. Fresh dragon fruit peel was taken, washed and cleaned, cut into pieces, and dried at 50℃ to constant weight. The dried peel was then pulverized and passed through a 100-mesh sieve to obtain dragon fruit peel powder. The powder was added to deionized water and stirred in a 65℃ water bath for 40 minutes. The pH of the system was adjusted to 5.0 using a 0.1 mol / L citrate-sodium citrate buffer solution. The temperature was lowered to 50℃, and the second compound enzyme preparation was added. The mixture was incubated and stirred for 4 hours for enzymatic hydrolysis. The temperature was then raised to 95℃ for 10 minutes to inactivate the enzyme. The mixture was cooled to room temperature and centrifuged at 5000 rpm for 2 seconds. 0 min, collect the supernatant, add 80% ethanol aqueous solution, let stand at 4℃ for 10 h to precipitate, filter, collect solid phase vacuum concentration, freeze dry at vacuum degree 10 Pa and -25℃ for 10 h, pulverize and pass through an 80 mesh sieve to obtain material B; the second compound enzyme preparation is composed of pectin methyl esterase, xylanase and polygalacturonase in a mass ratio of 3:1:0.3; the ratio of the dried dragon fruit peel powder, deionized water and the second compound enzyme preparation is 1 g: 25 mL: 0.012 g; Erythritol, mogroside V, steviol glycosides, sucralose, material A, and material B were added to a double cone mixer and mixed at 80 r / min for 25 min under the conditions of relative humidity RH≤45% and temperature 25℃ to obtain zero-calorie glycosyl powder; the mass ratio of erythritol, mogroside V, steviol glycosides, sucralose, material A, and material B was 480:0.5:0.2:0.1:240:60. γ-Cyclodextrin was dissolved in deionized water under water bath heating and stirring at 60°C. After cooling to 40°C, anhydrous ethanol was added and stirred evenly to obtain a binder. The mass ratio of γ-Cyclodextrin, deionized water and anhydrous ethanol was 100:120:30. Zero-calorie sugar base powder is fed into a fluidized bed granulator. The inlet air temperature is set to 60°C and the outlet air temperature to 40°C. The binder is atomized and sprayed while the material is tumbling. The atomization pressure is controlled at 0.25 MPa and the spray rate is 10 g / min. The spraying is stopped and the liquid is fluidized and dried at 60°C until the moisture content is ≤3.0%. The liquid is then passed through an 80-mesh sieve to obtain the zero-calorie sugar rich in dietary fiber. The mass ratio of the zero-calorie sugar base powder to the binder is 10:0.8.

[0027] Comparative Example 1 The difference from Example 2 is that the zero-calorie sugar is composed of erythritol, mogroside V, steviol glycoside, sucralose and material B in a mass ratio of 460:0.48:0.15:0.07:270.

[0028] Comparative Example 2 The difference from Example 2 is that the zero-calorie sugar is composed of erythritol, mogroside V, steviol glycoside, sucralose and material A in a mass ratio of 460:0.48:0.15:0.07:270.

[0029] Comparative Example 3 The difference from Example 2 is that the preparation method of material A includes the following steps: inulin and resistant dextrin are mixed, added to deionized water, heated and stirred in a water bath at 65°C for 35 min, the pH of the system is adjusted to 5.6 using 0.1 mol / L citrate-sodium citrate buffer, cooled to 58°C, stirred at 150 rpm for 2.0 h, heated to 90°C and held for 10 min, freeze-dried at a vacuum of 10 Pa and -20°C for 4 h, and pulverized through an 80-mesh sieve to obtain material A; the mass ratio of inulin, resistant dextrin, and deionized water is 5:1.5:80.

[0030] Comparative Example 4 The difference from Example 2 is that the preparation method of material B includes the following steps: adding dried dragon fruit peel powder to deionized water, stirring at a constant temperature of 60°C for 35 min, adjusting the pH of the system to 4.5 with 0.1 mol / L citrate-sodium citrate buffer solution, cooling to 48°C, stirring at this temperature for 3 h, heating to 95°C and holding for 10 min, cooling to room temperature, centrifuging at 4000 r / min for 15 min, collecting the supernatant, adding 80% ethanol aqueous solution, allowing to stand at 4°C for 9 h to precipitate, filtering, collecting the solid phase and concentrating under reduced pressure, freeze-drying at a vacuum of 10 Pa and -20°C for 9 h, pulverizing through an 80-mesh sieve to obtain material B; the ratio of dried dragon fruit peel powder to deionized water is 1 g: 20 mL.

[0031] Comparative Example 5 The difference from Example 2 is that only deionized water is used as the binder, and the amount used is the same as in Example 2 (zero-calorie sugar-based powder: binder = 9:0.7). The fluidized bed granulation parameters and drying conditions remain unchanged.

[0032] Comparative Example 6 The difference from Example 2 is that the zero-calorie sugar is composed of erythritol, material A and material B in a mass ratio of 460.7:220:50.

[0033] Performance testing 1. Dietary fiber content was determined according to standard GB 5009.88-2014.

[0034] 2. The calorific value was determined with reference to standard GB 28050-2025.

[0035] 3. Sensory flavor rating test: Accurately weigh 2.0g of each zero-calorie sugar sample to be tested and place it in a 100mL clean tasting cup. Add 50mL of room temperature purified water and gently stir until the sample is basically dispersed. Let it stand for 1 minute before use. All samples to be tested should be prepared under the same ratio, conditions, and time. Four scoring indicators are set: sweetness, aftertaste, off-flavor, and mouthfeel, with a maximum score of 25 points for each indicator. The scoring criteria for each indicator are as follows: Sweetness (25 points): 21-25 points: Pure and full sweetness, uniform sweetness, close to the sweetness of regular sucrose, without being too sweet or not sweet enough; 16-20 points: Relatively pure sweetness, slightly bland or slightly sweet, without any obvious disharmony; 11-15 points: Uneven sweetness, obviously bland or too sweet; 0-10 points: Strange sweetness, weak sweetness or no sweetness.

[0036] Aftertaste (25 points): 21-25 points: The aftertaste is long-lasting and mellow, with rich layers of sweetness and no hollow aftertaste; 16-20 points: There is obvious aftertaste, but the duration is short and the flavor is average; 11-15 points: The aftertaste is weak and there is almost no aftertaste; 0-10 points: There is no aftertaste, and the aftertaste is bland or bitter and astringent.

[0037] Odor (25 points): 21-25 points: No bitterness, no enzyme taste, no raw material off-flavor, no artificial flavor, pure flavor; 16-20 points: Very slight off-flavor exists, which can be ignored and does not affect the taste; 11-15 points: There is obvious slight bitterness and raw material off-flavor; 0-10 points: Strong off-flavor, obvious bitterness and off-flavor, cannot be eaten normally.

[0038] Taste upon entry (25 points): 21-25 points: Smooth and delicate upon entry, without any grainy or rough texture, and a refreshing taste; 16-20 points: Relatively smooth upon entry, with very fine grainy texture, but no rough texture; 11-15 points: Noticeable grainy texture, with a rougher taste; 0-10 points: Coarse grainy texture, with a gritty feel, and an extremely poor taste.

[0039] A professional sensory evaluation team of 10 people (without taste or smell impairments) was formed. The evaluators refrained from eating, smoking, and chewing gum for 30 minutes before the test, and rinsed their mouths with purified water and let them sit for 1 minute before the test. Each sample was evaluated in turn. After tasting each sample, the evaluators rinsed their mouths thoroughly with purified water and waited 3 minutes before tasting the next sample to avoid flavor interference. The 10 evaluators scored the samples independently. After all samples were scored, all scores were summed. The highest and lowest scores of each group were removed, and the average score was calculated. The sum of the average scores was the final sensory flavor score of the sample.

[0040] 4. Cold water solubility test Accurately weigh 2.0000g of the zero-calorie sugar sample to be tested (recorded as total mass M1) and place it in a clean beaker; accurately measure 40.00g of 25℃ deionized water and add it to the beaker, then turn on the electric stirrer and stir at a constant temperature for 5min; after stirring, transfer the entire solution to a pre-weighed centrifuge tube and centrifuge at 8000r / min for 10min to completely separate the undissolved solid residue; discard the supernatant, place the insoluble residue at the bottom of the centrifuge tube in a 105℃ forced-air drying oven to constant weight, cool to room temperature, weigh, and record the mass of the insoluble residue M2; each group of samples was tested in parallel 3 times, and the average value was used to calculate the solubility rate: Cold water solubility (%) = [(M1-M2) / M1] × 100% 5. Particle Formation Rate Test Place a 60-mesh sieve on the top layer, an 80-mesh sieve on the bottom layer, and a sieve tray at the bottom to assemble and fix the standard sieve; accurately weigh 100.00g of the total mass of the zero-calorie sugar product to be tested (denoted as G). 总 The particles are evenly spread on the surface of the upper 60-mesh sieve; a manual horizontal vibrating sieve method is used to vibrate and sieve at a uniform speed for 5 minutes to ensure that the particles are fully classified and do not stick together or agglomerate; the particles in the 60-80 mesh range remaining between the two sieves are collected, and the mass of qualified particles is accurately weighed (denoted as G). 合格 Each group of samples was sieved in parallel three times, and the average value was used to calculate the molding rate. Particle forming rate (%) = (G 合格 / G 总 ) × 100% 6. Stability test during room temperature storage Accurately weigh 200.00g of the zero-calorie sugar sample to be tested and place it in a clean, dry, sealed sample bottle, protecting it from light. Place the sample bottle in a constant temperature and humidity test chamber with preset temperature and humidity conditions and store it continuously for 30 days. During this period, do not open or move the sample. After the storage period, take out the sample and sieve it at a uniform speed for 3 minutes using a 40-mesh standard sieve to completely separate loose particles from agglomerated particles. Collect the agglomerated material that cannot pass through the sieve holes and accurately weigh the mass of the agglomerated material (denoted as G). 结块 Each group of samples was tested in parallel three times, and the agglomeration rate was calculated by taking the average value. clumping rate (%) = (G 结块 / 200.00)×100% The test results are shown in Table 1 below.

[0041] Table 1 The test results above show that, according to the latest GB 28050-2025 rules, this product contains no protein, fat, or digestible carbohydrates, and only dietary fiber is converted into energy at 8 kJ / g. The energy range of each sample is lower than the legal threshold for zero energy in solid foods (≤17kJ / 100g), which fully complies with the national standard definition of zero-calorie food.

[0042] Example 1 had the lowest amount of dietary fiber added, Example 2 improved the ratio, and Example 3 had the highest amounts of inulin, resistant dextrin, and dragon fruit peel extract, with a longer enzymatic hydrolysis time and more complete extraction, resulting in the best total dietary fiber content. Example 1 had a short enzymatic hydrolysis time and low enzyme dosage, resulting in a slight residual bitterness and weaker sweetness, leading to a lower overall sensory score. Example 2 had the optimal process parameters, thorough enzymatic hydrolysis, and effectively removed the off-flavors of the raw materials. Combined with the appropriate ratio of mogroside V, steviol glycosides, and sucralose, it had a pure sweetness, a long-lasting aftertaste, and the best sensory performance. Example 3 had the highest dietary fiber content, but the high plant fiber content slightly weakened the sweetness's clarity, resulting in a slightly lower sensory score than Example 2, but the overall flavor was excellent, with no off-flavors and a delicate texture. Examples 1-3 showed improvements with increasing amounts of compound enzymes and enzymatic hydrolysis temperature. With higher adaptability and longer enzymatic hydrolysis time, it can be fully degraded into water-soluble small molecule polysaccharide fragments, significantly improving the product's cold water solubility. Additionally, Example 3 has a higher binder ratio and better atomization granulation parameters, resulting in better particle porosity and further improving the dissolution rate and solubility. Example 1 has milder granulation parameters, resulting in average particle bonding uniformity and a relatively low forming rate. Example 2 has a more sufficient γ-cyclodextrin binding system, with better adaptability to fluidized bed granulation temperature and atomization pressure compared to Example 3, resulting in higher particle regularity, the highest proportion of qualified particles, and the best granulation forming effect. Example 3 has the highest binder addition ratio, which can form a dense protective film on the particle surface, effectively isolating moisture in the air and inhibiting particle moisture absorption and clumping. Example 1 uses the least amount of γ-cyclodextrin, resulting in the weakest protective effect and a slightly higher clumping rate, but it still has good storage stability.

[0043] After removing material A from Comparative Example 1, the lack of dietary fiber's moisture dispersion and flavor buffering effect resulted in a decrease in the product's sweetness and smoothness, and a significant reduction in sensory scores.

[0044] After removing material B from Comparative Example 2, the dietary fiber content of the product decreased slightly, the sensory quality declined, the product lost its natural fruity aroma and layering, the erythritol sweetness was plain and bland without a lasting aftertaste, the bitterness was slightly prominent, and the sensory score was significantly lower than the baseline group. The data in this group indicate that material B is not simply a fiber supplement, but a key functional auxiliary material for flavor optimization and rich taste layers in this invention, and it is irreplaceable in improving the product's edible quality.

[0045] Comparative Example 3 retains all the raw material ratios of Material A, but omits the combined enzymatic hydrolysis process of inulinase and transglucosidase. The unhydrolyzed inulin and resistant dextrin exist in a high molecular polymer structure with large molecular chains and extremely poor water solubility, which causes the product's cold water solubility to drop from 96.8% to 82.4%, significantly deteriorating the uniformity of dissolution. At the same time, the large molecular polysaccharides have a slightly powdery and rough feel, and the original taste of the raw materials remains, resulting in a decline in sensory flavor.

[0046] Comparative Example 4 retained the dragon fruit peel raw material, but omitted the synergistic enzymatic hydrolysis process of pectin methyl esterase, xylanase, and polygalacturonase. The unhydrolyzed dragon fruit peel powder contained a large amount of insoluble hard pectin, lignin, and bitter active substances, which not only failed to exert the flavor enhancement effect, but also introduced obvious green off-flavors and a grainy texture, resulting in a significant decrease in the product's sensory score. At the same time, the insoluble macromolecular components severely hindered the water penetration and dispersion, and after storage, there was slight sedimentation and a rough taste.

[0047] Comparative Example 5 only replaced the binder system. Pure water has no coating, slow-release, or binding functions, and cannot make the powder agglomerate and form uniformly. The powder is loose, contains many fine powders, and has uneven particle size. At the same time, it lacks the molecular coating moisture-proof film structure of γ-cyclodextrin, and the powder easily absorbs environmental moisture, resulting in serious failure of storage stability.

[0048] Comparative Example 6 removed trace amounts of mogroside V, steviol glycosides, and sucralose, retaining only erythritol as the single sweet base. Erythritol has a refreshing sweetness but a thin sweetness and no aftertaste. The product has a single sweetness level, a bland taste, and a hollow aftertaste.

[0049] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, features in the embodiments of the present invention can be combined with each other unless otherwise specified.

Claims

1. A zero-calorie sugar rich in dietary fiber and its preparation method, characterized in that, Includes the following steps: S1. The first complex enzyme preparation, composed of inulinase and transglucosidase, is used to enzymatically hydrolyze the mixture of inulin and resistant dextrin to obtain material A; S2. Add the dried dragon fruit peel powder to deionized water, heat in a water bath and stir evenly. Adjust the pH of the system to 4.0-5.0, and enzymatically hydrolyze it at 45-50℃ using a second complex enzyme preparation composed of pectin methyl esterase, xylanase and polygalacturonase to obtain material B. S3. Take erythritol, mogroside V, steviol glycoside, sucralose, material A and material B and mix them evenly to obtain zero-calorie sugar-based powder; S4. Dissolve γ-cyclodextrin in deionized water, add anhydrous ethanol, stir well to obtain the adhesive; S5. The zero-calorie sugar base powder is fed into a fluidized bed granulator, atomized and sprayed into the binder, fluidized and dried, and sieved to obtain the zero-calorie sugar rich in dietary fiber.

2. The zero-calorie sugar rich in dietary fiber and its preparation method according to claim 1, characterized in that, In step S1, the mass ratio of inulinase to transglucosidase is 3-5:1-2.

3. The zero-calorie sugar rich in dietary fiber and its preparation method according to claim 1, characterized in that, In step S1, the mass ratio of inulin, resistant dextrin, and complex enzyme is 4-6:1-2:0.06-0.

07.

4. The zero-calorie sugar rich in dietary fiber and its preparation method according to claim 1, characterized in that, In step S2, the mass ratio of pectin methylesterase, xylanase and polygalacturonase is 2-3:0.5-1:0.1-0.

3.

5. The zero-calorie sugar rich in dietary fiber and its preparation method according to claim 1, characterized in that, In step S2, the ratio of the dried dragon fruit peel powder, deionized water, and the second compound enzyme preparation is 1g: 15-25mL: 0.008-0.012g.

6. The zero-calorie sugar rich in dietary fiber and its preparation method according to claim 1, characterized in that, In step S3, the mass ratio of erythritol, mogroside V, steviol glycoside, sucralose, material A and material B is 400-480: 0.4-0.5: 0.1-0.2: 0.05-0.1: 180-240: 30-60.

7. The zero-calorie sugar rich in dietary fiber and its preparation method according to claim 1, characterized in that, In step S4, the mass ratio of the γ-cyclodextrin, deionized water, and anhydrous ethanol is 80-100:100-120:20-30.

8. The zero-calorie sugar rich in dietary fiber and its preparation method according to claim 1, characterized in that, In step S5, the mass ratio of the zero-calorie sugar base powder to the binder is 8-10:0.6-0.

8.

9. A zero-calorie sugar rich in dietary fiber, characterized in that, It is prepared using the method for preparing a zero-calorie sugar rich in dietary fiber as described in any one of claims 1-8.

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