Preparation method of prebiotic-containing composite sugar

Abstract

The invention discloses a preparation method of composite sugar containing prebiotics. The preparation method comprises the following steps: S1, crushing sugarcanes into shredded sugarcanes, squeezing and extracting juice by a light pressing method to obtain light pressed juice and shredded sugarcanes, and extracting juice from the shredded sugarcanes by an exuding method to obtain exuded juice; s2, hydrolyzing a part of the exuded juice to obtain invert sugar; s3, mixing the lightly pressed juice, the residual exuded juice and invert sugar, adding metal salt or metal oxide, adjusting pH, and separating to obtain clear juice; s4, evaporating and concentrating the clear juice to obtain syrup; s5, adding glucoside hydrolase, glycosyltransferase and isomerase into the syrup for catalytic reaction to obtain enzyme catalyzed syrup; s6, separating the syrup subjected to enzyme catalysis to obtain pure syrup; and S7, boiling the pure syrup as a raw material into massecuite, and carrying out crystallization assisting and honey separation to obtain the sugar product. The sugar production process provided by the invention is carried out under the meta-acid and medium-high temperature conditions, harmful by-products are effectively reduced, and the nutritional value and safety of the sugar are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of functional sugar, in particular to a preparation method of composite sugar containing prebiotics. BACKGROUND

[0002] The traditional sugar production process includes juice extraction, clarification, evaporation and sugar boiling processes, such as white sugar for both domestic and industrial use. In the production process using sugarcane as raw material, five extractions, multi-aid clarification, five-effect evaporation, three-system sugar boiling and other links are required. There are problems such as long process, high energy consumption, large equipment investment and single sugar product. Especially in the clarification stage, multiple chemical aids such as lime, phosphoric acid and polyacrylamide are added, and the amino acids and other substances in sugarcane are seriously lost. In the sugar boiling process, the main purpose is to recover sucrose and reduce non-sucrose substances in the product to the greatest extent. The sugar juice needs to be boiled for a long time to crystallize, which consumes time and energy. The final sugar product is only high-purity sucrose white sugar and other sugar products. The preparation process of black sugar and brown sugar requires high temperature and high alkali, which may contain harmful substances such as acrylamide, and there is a certain risk of food safety.

[0003] Enzyme preparations have been widely used in sugar production. Currently reported enzymes include amylase, pectinase, dextranase and complex enzyme, which are mainly used to remove non-sugar substances in sugar juice and improve its purity. However, there are few reports on the production of functional sugar by enzymatic method in the sugar production process.

[0004] From the perspective of consumers' demand for "safety" and "nutrition" of domestic sugar, the products produced by the existing sugar production process cannot fully meet the requirements. At the same time, with the rapid rise of new sweeteners such as erythritol and allulose and the continuous improvement of consumers' health awareness, it is difficult for white sugar and other sugar products, which occupy an important position in the sweetener industry, to maintain their irreplaceable position in the market with the characteristics of "sweet" and "pure".

[0005] Therefore, it is urgent to make technical innovation and quality improvement in the sugar production process, and to develop a preparation method of composite sugar with rich nutrition and prebiotics. SUMMARY

[0006] The purpose of the present application is to provide a preparation method of composite sugar containing prebiotics. The production process of the composite sugar proposed in the present application is carried out under acidic, medium-high temperature conditions, which greatly reduces the Maillard reaction and the formation of 5-hydroxymethylfurfural, and improves the safety of the product.

[0007] The present application is realized by the following technical solutions:

[0008] A preparation method of composite sugar containing prebiotics, comprising the following steps:

[0009] S1. Juice extraction: Sugarcane is cut into sections, washed, and crushed into sugarcane shreds. The sugarcane shreds are then pressed to extract juice using a light pressing method to obtain lightly pressed juice and lightly pressed sugarcane shreds. The lightly pressed sugarcane shreds are then extracted by an exudation method to obtain exudate juice.

[0010] S2, Sucrose hydrolysis: Take a portion of the exudate and hydrolyze it using acid or enzymatic methods to obtain invert sugar;

[0011] S3, Purification: After mixing the lightly pressed juice, the remaining exudate and invert sugar, add metal salts or metal oxides, adjust the pH to 5.0~7.0, filter, heat and centrifuge to obtain clear juice;

[0012] S4. Concentration: The clear juice is evaporated and concentrated under medium temperature conditions to obtain syrup;

[0013] S5. Catalysis: Glycoside hydrolase, glycosyltransferase and isomerase are added to the syrup to carry out the catalytic reaction. The enzyme activity ratio of glycoside hydrolase, glycosyltransferase and isomerase is 1:3:1~2:9:5, the total amount of enzyme added is 15~40 U / mL, the reaction temperature is 45℃~65℃, and the reaction time is 15~90 min to obtain the enzyme-catalyzed syrup.

[0014] S6. Separation: The enzyme-catalyzed syrup is separated by adding metal salts or metal oxides to obtain pure syrup;

[0015] S7. Sugar formation: Pure syrup is boiled into a sugar paste, which is then dried after crystallization and separation to obtain sugar products. The by-product molasses is processed to produce other sugars or new sweeteners.

[0016] The present invention proposes a method for preparing prebiotic-containing compound sugar. By employing different extraction methods on sugarcane raw materials, the extraction efficiency is improved, and conditions for efficient hydrolysis of sucrose in the juice are created. During the purification process of the sugarcane juice, metal salts and lime are added, and the quality of the juice is improved through simple heating and centrifugation. The residual metal salts can be used as activators for subsequent enzymes to participate in enzymatic reactions. After concentration, glycoside hydrolase, glycosyltransferase, and isomerase are added to the syrup to promote the conversion of sucrose and the efficient generation of prebiotics such as oligosaccharides and allulose in a sucrose solution system containing glucose and fructose. Then, metal salts are added again to enrich the prebiotics and clarify the syrup. Oligosaccharides and other substances are finally incorporated into the sugar product through a crystallization process. The molasses obtained by separating the molasses still contains prebiotics and other products, which can be used as raw materials for other sugars and novel sweeteners.

[0017] Preferably, the light pressure in step S1 is 0.3 × 10⁻⁶. 6 ~4.0×10 6 Pa, the process parameters for the percolation method are: percolation water temperature 35℃~65℃, and percolation water content 3%~15% of sugarcane fiber.

[0018] Further preferably, the light pressure in step S1 is 0.8 x 10 6 ~2.0 x 10 6 Pa, and the process parameters of the leaching method are that the water temperature for leaching is 45°C~55°C, and the water for leaching is 8%~10% of the amount of the cane.

[0019] Preferably, the water used in the cleaning and leaching method in step S1 is the condensed water obtained by evaporation in step S4.

[0020] Preferably, 20%~80% of the leaching juice in step S2 is hydrolyzed by acid or enzyme method. The enzyme method process specifically uses sucrose enzyme, the temperature is 45°C~60°C, the pH is 4.5~6.5, and the mass / volume ratio of the amount of sucrose enzyme added to the leaching juice is 20~60 mg / L. The acid method process specifically uses food-grade acid as the catalyst for hydrolysis by heating, the food-grade acid is selected from hydrochloric acid and phosphoric acid, the amount of the food-grade acid added accounts for 0.2%~1.0% of the total mass of the leaching juice, the hydrolysis temperature is 55°C~85°C, and the hydrolysis time is 30~60 min.

[0021] Preferably, the metal in step S3 is magnesium, and the metal salt or metal oxide includes magnesium carbonate, magnesium oxide, and magnesium sulfate, and the amount of the metal added is 50~300 mg / L, the pH is adjusted to 5.5~6.9 using lime, and the heating temperature is 65°C~100°C.

[0022] Further preferably, the metal salt in step S3 is magnesium sulfate, the amount of the metal added is 100~200 mg / L, the pH is adjusted to 6.0~6.5 using lime, and the heating temperature is 85°C~90°C.

[0023] Preferably, the concentration process parameters in step S4 are that the temperature is controlled at 60°C~100°C, and the concentration of the obtained sugar syrup is 30~50 °Bx.

[0024] Preferably, the glycoside hydrolase in step S5 is selected from one or more of α-glucosidase and α-glucanase, the glycosyltransferase is one or more of dextransucrase and fructosyltransferase, the isomerase is D-psicose-3-epimerase, and the catalytic reaction conditions are that the reaction temperature is 45°C~65°C, and the reaction time is 30~60 min.

[0025] Further preferably, the enzyme activity ratio of the glycoside hydrolase, the glycosyltransferase, and the isomerase in step S5 is 3:8:2~3:10:5.

[0026] Still further preferably, the enzyme activity ratio of the glycoside hydrolase, the glycosyltransferase, and the isomerase in step S5 is 3:8:3, and the enzyme activity ratio of α-glucanase, α-glucosidase, dextransucrase, fructosyltransferase, and D-psicose-3-epimerase is 2:1:2:6:3.

[0027] Preferably, the metal in step S6 is magnesium, and the metal salt or metal oxide includes magnesium carbonate, magnesium oxide and magnesium sulfate, and the addition amount is 30-100 mg / L.

[0028] Further preferably, the metal salt or oxide in step S6 is magnesium oxide, and the addition amount is 50 mg / L.

[0029] Preferably, the sugar paste prepared in step S7 is not watered when the sugar paste is divided, and the moisture content of the dried sugar is controlled to be 0.5%-3.0%.

[0030] The specific steps of the crystal assisting method are as follows: the sugar paste is cooled in the crystal assisting machine through mechanical stirring, so as to reduce the solubility of sucrose, and finally promote the continuous generation of crystals.

[0031] Compared with the prior art, the beneficial effects of the present application are as follows:

[0032] 1. The juice extraction of sugarcane adopts the light pressure pressing and exudation process, the purity of the cane juice is high, and the steam condensate water can be used as a resource.

[0033] 2. In the preparation method, part of the sucrose is hydrolyzed into monosaccharides, so that a certain amount of small molecule acceptors exist in the multi-enzyme catalytic reaction system, which significantly promotes the synthesis of prebiotics such as oligosaccharides and allulose, and the existence of monosaccharides can also reduce the solubility of sucrose to improve the crystallization efficiency.

[0034] 3. In the sugar production, part of the sucrose is converted into other functional substances by the action of enzymes, which not only reduces the sucrose content of the sugar, but also greatly improves the nutritional value and taste of the sugar, and the enzyme is inactivated in the subsequent sugar-making section, which is safe.

[0035] 4. The whole sugar production process is carried out under the conditions of partial acid and medium-high temperature, which greatly reduces the Maillard reaction and the formation of 5-hydroxymethylfurfural and other substances, and improves the safety of the product.

[0036] 5. The by-product molasses contains substances such as oligosaccharides, which can be used as raw materials for preparing new sweeteners or other sugars, and can effectively promote the chain, supplement and extension of the industry.

[0037] 6. The sugar production process of the present application is carried out under the conditions of partial acid and medium-high temperature, which can effectively reduce harmful by-products, enrich prebiotics while reducing the sucrose content of the product, and improve the nutritional value and safety of the sugar. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The flow chart of the preparation method of the prebiotic-containing composite sugar according to the present application is shown. DETAILED DESCRIPTION

[0039] The present invention will be further described in detail below with reference to the embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions in the art or as recommended by the manufacturer; the raw materials and reagents used, unless otherwise specified, are considered to be commercially available materials and reagents that can be obtained through conventional markets and other commercial channels.

[0040] Example 1

[0041] like Figure 1 As shown, a method for preparing a prebiotic-containing complex sugar includes the following steps:

[0042] S1. Juice Extraction: After the sugarcane arrives at the factory, it is cut into sections and crushed into sugarcane shreds, using a pressure of 8×10. 5 After lightly pressing Pa to extract juice, lightly pressed juice and lightly pressed sugarcane fibers are obtained. The lightly pressed sugarcane fibers are then percolated with condensed water at a water temperature of 55°C and 8% of the sugarcane weight to extract juice, and the water used for washing and percolation is the condensed water obtained from evaporation in step S4.

[0043] S2, Sucrose hydrolysis: 20 wt% of the exudate was hydrolyzed by adding sucrase at a temperature of 50°C, pH 5.5, and the amount of sucrase added was 40 mg / L to obtain invert sugar;

[0044] S3. Clarification: After mixing the lightly pressed juice, the remaining exudate, and the invert sugar, add magnesium sulfate at a rate of 200 mg / L (based on the total volume of the lightly pressed juice, the remaining exudate, and the invert sugar). Adjust the pH to 6.5, then filter through a sieve, heat to 85°C, and centrifuge to obtain clear juice.

[0045] S4. Concentration: The clear juice is concentrated into a syrup with a concentration of 40 °Bx in a four-effect evaporation system (temperature 65℃~95℃);

[0046] S5. Catalysis: α-glucanase, α-glucosidase, glucan sucrase, fructosyltransferase, and D-allulose-3-epimerase with an enzyme activity ratio of 2:1:2:6:3 were added to the syrup to catalyze the reaction. The total amount of enzyme added was 25 U / mL, the reaction temperature was 55℃, and the reaction time was 45 min to obtain the enzyme-catalyzed syrup.

[0047] S6. Separation: Magnesium oxide is added to the enzyme-catalyzed syrup for filtration and centrifugation. The amount added is 50 mg / L to obtain pure syrup.

[0048] S7. Sugar formation: Pure syrup is boiled into a sugar paste, which is then dried after crystallization and separation to obtain sugar products. The moisture content of the dried sugar is controlled at 0.5% to 3%. The by-product molasses is pretreated to prepare new sweeteners such as allulose or sugar.

[0049] Comparative Example 1

[0050] The same as Example 1, except that only the exuding juice is used in step S1, and the remaining exuding juice and invert sugar are mixed in step S3.

[0051] Comparative Example 2

[0052] The same as Example 1, except that only the light press juice is used in step S1; 20wt% of the light press juice is hydrolyzed by acid or enzyme method to obtain invert sugar in step S2; and the remaining light press juice and invert sugar are mixed in step S3.

[0053] Comparative Example 3

[0054] The same as Example 1, except that the enzyme catalytic reaction in step S5 is not performed.

[0055] Comparative Example 4

[0056] The same as Example 1, except that the enzyme activity ratio of α-glucanase to α-glucosidase is 2:1 in step S5.

[0057] Comparative Example 5

[0058] The same as Example 1, except that the enzyme activity ratio of dextransucrase to fructosyltransferase is 1:3 in step S5.

[0059] Comparative Example 6

[0060] The same as Example 1, except that D-alloketose-3-epimerase is added in step S5.

[0061] Comparative Example 7

[0062] The same as Example 1, except that the enzyme activity ratio of α-glucanase to α-glucosidase to D-alloketose-3-epimerase is 2:1:3 in step S5.

[0063] Comparative Example 8

[0064] The same as Example 1, except that the enzyme activity ratio of dextransucrase to fructosyltransferase to D-alloketose-3-epimerase is 2:6:3 in step S5.

[0065] Comparative Example 9

[0066] The same as Example 1, except that the enzyme activity ratio of α-glucanase to α-glucosidase to dextransucrase to fructosyltransferase is 2:1:2:6 in step S5.

[0067] Comparative Example 10

[0068] The same as example 1, except that step S2 hydrolysis is not performed, and the exudation juice and light pressure juice are mixed in step S3.

[0069] The materials obtained in example 1 and comparative examples 1-10 are detected, and the product quality is shown in table 1 as follows:

[0070] Table 1 Material and product quality

[0071] From table 1, it is obtained that the sugar cane juice obtained by using light pressure or exudation alone in comparative example 1 and comparative example 2 is not as good as that in example 1, and the purity of the sugar cane juice obtained by the combined action of the two is much higher than that in comparative example 1 or comparative example 2. In comparative examples 3-9, the use of glycoside hydrolytic enzyme, glycosyltransferase and isomerase for catalytic reaction compared with the use of one or two of the enzymes alone reduces the sucrose content of sugar and increases the content of oligosaccharide, greatly improving the nutritional value and taste of sugar. In comparative example 10, no sucrose hydrolysis is performed, compared with the partial hydrolysis of sucrose into monosaccharide in example 1, the hydrolysis reaction significantly promotes the synthesis of prebiotics such as oligosaccharide and allulose, and the presence of monosaccharide can also reduce the solubility of sucrose to improve the crystallization efficiency.

[0072] The types and contents of amino acids in the sugar obtained in example 1 and comparative examples 1 and 2 are shown in table 2 as follows:

[0073] Table 2

[0074] Example 2

[0075] The same as example 1, except that:

[0076] In step S1, the light pressure is 2.0 x 10 6 Pa, and the process parameters of the exudation method are that the water temperature for exudation is 45℃, and the exudation water is 10% of the amount of cane.

[0077] In step S3, magnesium carbonate is added in an amount of 100 mg / L, lime is used to adjust the pH to 6.0, and the heating temperature is 90℃.

[0078] In step S4, the concentration process parameters are that the temperature is 60℃-80℃, and the obtained sugar syrup concentration is 30 °Bx.

[0079] Example 3

[0080] The same as example 1, except that:

[0081] In step S1, the light pressure is 0.3 x 10 6Pa, the process parameters of the exudation method are that the water temperature for exudation is 35°C, and the exudation water is 15% of the amount of the cane.

[0082] In step S2, 80% of the exudation juice is hydrolyzed by sucrose enzyme, the temperature is 45°C, the pH is 6.5, the mass / volume ratio of the sucrose enzyme addition amount to the exudation juice is 20 mg / L.

[0083] In step S3, the magnesium salt is magnesium carbonate, the addition amount is 50 mg / L, the pH is adjusted to 5.5 by using lime, and the heating temperature is 65°C.

[0084] In step S4, the concentration process parameters are that the temperature is 60°C-85°C, and the obtained sugar syrup concentration is 30 °Bx.

[0085] In step S5, the enzyme activity ratio of glycoside hydrolase, glycosyltransferase and isomerase is 3:8:2, the total enzyme addition amount is 15 U / mL, and the catalytic reaction conditions are that the reaction temperature is 65°C and the reaction time is 30 min.

[0086] In step S6, the metal salt is magnesium carbonate, and the addition amount is 30 mg / L.

[0087] Example 4

[0088] The same as example 1, except that:

[0089] In step S1, the light pressure is 4.0 x 10 6 Pa, the process parameters of the exudation method are that the water temperature for exudation is 65°C, and the exudation water is 3% of the amount of the cane.

[0090] In step S2, 80% of the exudation juice is hydrolyzed by sucrose enzyme, the temperature is 60°C, the pH is 4.5, and the mass / volume ratio of the sucrose enzyme addition amount to the exudation juice is 60 mg / L.

[0091] In step S3, magnesium oxide is added, the addition amount is 300 mg / L, the pH is adjusted to 6.9 by using lime, and the heating temperature is 100°C.

[0092] In step S4, the concentration process parameters are that the temperature is 65°C-100°C, and the obtained sugar syrup concentration is 50 °Bx.

[0093] In step S5, the enzyme activity ratio of glycoside hydrolase, glycosyltransferase and isomerase is 3:10:5, the total enzyme addition amount is 40 U / mL, and the catalytic reaction conditions are that the reaction temperature is 45°C and the reaction time is 60 min.

[0094] In step S6, the metal salt is magnesium sulfate, and the addition amount is 100 mg / L.

[0095] The above description of the embodiments is only used to help understand the technical solutions of the present application and its core ideas. It should be pointed out that for those skilled in the art, without departing from the principles of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A method for preparing a prebiotic-containing complex sugar, characterized in that, Includes the following steps: S1. Juice extraction: Sugarcane is cut into sections, washed, and crushed into sugarcane shreds. The sugarcane shreds are then pressed to extract juice using a light pressing method to obtain lightly pressed juice and lightly pressed sugarcane shreds. The lightly pressed sugarcane shreds are then extracted by an exudation method to obtain exudate juice. S2, Sucrose hydrolysis: Take a portion of the exudate and hydrolyze it using acid or enzymatic methods to obtain invert sugar; S3, Purification: After mixing the lightly pressed juice, the remaining exudate and invert sugar, add metal salts or metal oxides, adjust the pH to 5.0~7.0, filter, heat and centrifuge to obtain clear juice; S4. Concentration: The clear juice is evaporated and concentrated under medium temperature conditions to obtain syrup; S5. Catalysis: Glycoside hydrolase, glycosyltransferase and isomerase are added to the syrup to carry out the catalytic reaction. The enzyme activity ratio of glycoside hydrolase, glycosyltransferase and isomerase is 1:3:1~2:9:5, the total amount of enzyme added is 15~40 U / mL, the reaction temperature is 45℃~65℃, and the reaction time is 15~90 min to obtain the enzyme-catalyzed syrup. S6. Separation: The enzyme-catalyzed syrup is separated by adding metal salts or metal oxides to obtain pure syrup; S7. Sugar formation: Pure syrup is boiled into a sugar paste, which is then dried after crystallization and separation to obtain sugar products. The by-product molasses is processed to produce other sugars or new sweeteners.

2. The preparation method according to claim 1, characterized in that, The light pressure mentioned in step S1 is 0.3 × 10⁻⁶. 6 ~4.0×10 6 Pa, the process parameters for the percolation method are: percolation water temperature 35℃~65℃, and percolation water content 3%~15% of sugarcane fiber.

3. The preparation method according to claim 1 or 2, characterized in that, The water used for cleaning and leaching in step S1 is the condensate obtained from evaporation in step S4.

4. The preparation method according to claim 1 or 2, characterized in that, In step S2, 20% to 80% of the exudate is hydrolyzed by acid or enzymatic methods. The enzymatic process conditions are: temperature 45°C to 60°C, pH 4.5 to 6.

5.

5. The preparation method according to claim 1 or 2, characterized in that, The metal mentioned in step S3 is magnesium, and the metal salt or metal oxide includes magnesium carbonate, magnesium oxide and magnesium sulfate, with an addition amount of 50~300 mg / L. The pH is adjusted to 5.5~6.9 using lime, and the heating temperature is 65℃~100℃.

6. The preparation method according to claim 1 or 2, characterized in that, The concentration process parameters in step S4 are: temperature controlled at 60℃~100℃, and the resulting syrup concentration is 30~50 °Bx.

7. The preparation method according to claim 1 or 2, characterized in that, In step S5, the glycoside hydrolase is selected from one or more of α-glucosidase and α-glucanase, the glycosyltransferase is selected from one or more of glucan sucrase and fructosyltransferase, the isomerase is D-allulose-3-epimerase, and the catalytic reaction conditions are: reaction temperature 45°C~65°C, reaction time 30~60 min.

8. The preparation method according to claim 7, characterized in that, In step S5, the enzyme activity ratio of glycoside hydrolase, glycosyltransferase and isomerase is 3:8:3 to 3:10:

5.

9. The preparation method according to claim 1 or 2, characterized in that, The metal mentioned in step S6 is magnesium, and the metal salt or oxide includes magnesium carbonate, magnesium oxide and magnesium sulfate, with an addition amount of 30~100 mg / L.

10. The preparation method according to claim 1 or 2, characterized in that, When separating the sugar paste prepared in step S7, no water is added, and the moisture content of the dried sugar is controlled at 0.5%~3.0%.

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