阅读说明：本技术 一种以原糖为原料制备低聚果糖的方法 (Method for preparing fructo-oligosaccharide by using raw sugar as raw material ) 是由 李克文 栾庆民 李泉荟 贾慧慧 张莉 熊小兰 韩敏 徐虹 李新华 于 2019-10-29 设计创作，主要内容包括：本发明涉及一种以原糖为原料制备低聚果糖的方法,包括：先配制浓度为30wt％-70wt％的原糖溶液,在配制完成的原糖溶液中加入果糖基转移酶糖化4～100h,得到糖化液；再将糖化液经脱色、超滤、真空浓缩得到液体低聚果糖；最后将液体低聚果糖经色谱分离、浓缩、干燥,制得固体低聚果糖。本发明以原糖为原料制备的低聚果糖,突破了行业内目前以菊芋、菊苣或白砂糖为原料生产低聚果糖的生产模式,使用了成本更低的原糖代替,大大地降低了工业化生产的成本。(The invention relates to a method for preparing fructo-oligosaccharide by taking raw sugar as a raw material, which comprises the following steps: firstly, preparing an original sugar solution with the concentration of 30-70 wt%, and adding fructosyltransferase into the prepared original sugar solution for saccharification for 4-100 hours to obtain a saccharification solution; decolorizing, ultrafiltering and vacuum concentrating the saccharified liquid to obtain liquid oligofructose; and finally, carrying out chromatographic separation, concentration and drying on the liquid fructo-oligosaccharide to obtain the solid fructo-oligosaccharide. The invention uses the raw sugar as the raw material to prepare the fructo-oligosaccharide, breaks through the current production mode of producing the fructo-oligosaccharide by using the jerusalem artichoke, the chicory or the white granulated sugar as the raw material in the industry, uses the raw sugar with lower cost to replace, and greatly reduces the cost of industrial production.)

1. A method for preparing fructo-oligosaccharide from raw sugar comprises the following steps:

(1) preparing a raw sugar solution with the concentration of 30-70 wt%, and adding fructosyltransferase into the prepared raw sugar solution for saccharification for 4-100 h to obtain a saccharification solution;

(2) decoloring, ultrafiltering and vacuum concentrating the saccharified liquid obtained in the step (1) to obtain liquid fructo-oligosaccharide;

(3) and (3) carrying out chromatographic separation, concentration and drying on the liquid fructo-oligosaccharide obtained in the step (2) to obtain solid fructo-oligosaccharide.

2. The method according to claim 1, wherein in the step (1), the concentration of the raw sugar solution is 40 to 60 wt%.

3. The process according to claim 1, wherein the fructosyltransferase is added in an amount of 0.3 to 3L/t dry basis in step (1).

4. The production method according to claim 1, wherein in the step (1), the saccharification conditions are: the temperature is 40-75 ℃, the pH is 5.0-7.0, and the time is 10-80 h.

5. The preparation method according to claim 1, wherein the decolorization is performed by using a granular activated carbon column with a diameter of 10-30 meshes, the temperature of the granular activated carbon column is 70-80 ℃, the flow rate of the saccharification liquid is 2-3 BV, and the decolorization time is 0.5-1.0 h.

6. The method according to claim 1, wherein in the step (2), the ultrafiltration is performed by using an ultrafiltration membrane having a membrane molecular weight of 1w to 10w Da at an operating pressure of 0.1 to 1.0MPa and a temperature of 30 to 50 ℃.

7. The preparation method according to claim 1, wherein in the step (2), the vacuum concentration is carried out at an operating pressure of 0.1 to 1.0MPa and a temperature of 65 ℃, and the mass percentage of solids in the obtained liquid fructo-oligosaccharide is 60 to 75 percent.

8. The method according to claim 1, wherein in the step (3), the chromatographic separation conditions are: the operating pressure is 0.1-1.0 MPa, the temperature is 30-50 ℃, and the mass percentage of fructo-oligosaccharide in the liquid fructo-oligosaccharide after chromatographic separation is 70-95%.

9. The method according to claim 1, wherein in the step (3), the drying is spray drying or belt drying.

Technical Field

The invention belongs to the technical field of fructo-oligosaccharide synthesis, and particularly relates to a method for preparing fructo-oligosaccharide by using raw sugar as a raw material.

Background

Fructo-oligosaccharide, also known as fructooligosaccharide or kestose family oligosaccharide, is a natural active ingredient present in fruits, vegetables, honey and other substances, and is also an excellent water-soluble dietary fiber. Fructo-oligosaccharide is obtained by converting fructosyltransferase by modern bioengineering technology, refining and concentrating, becomes a functional food base material widely popular in the international food market in the last decade by virtue of the superior physiological function of fructo-oligosaccharide, has an application range of more than 500 foods, health care products and medicines, and is known as a new health sugar source in the twenty-first century.

Natural fructooligosaccharides are present in a variety of plants or fruits, such as chicory, Jerusalem artichoke, banana, onion, honey, and the like. Commercial fructooligosaccharides can be extracted directly from plants or enzymatically produced. The fructo-oligosaccharide is a beneficial food additive with complete nutrition which is commonly used internationally, can effectively exert the physiological activity of probiotics, selectively increase the number of floras and is a growth promoting factor of the probiotics. In addition, fructo-oligosaccharide as a dietary fiber can promote intestinal flora balance, improve gastrointestinal function, and has multiple physiological functions of loosening bowel to relieve constipation, reducing blood lipid, regulating blood sugar, etc.

The raw sugar is light brown, is the most main sugar product in international trade, and can be used as a raw material for sugar finishing. The raw sugar cane sugar which is not crystallized is edible and is natural green raw sugar. The raw sugar cane obtained by crushing and drying the cane and grinding the cane is directly edible. The sugarcane raw sugar obtained by the simple processing technology keeps the original characteristics of the sugarcane, is rich in various mineral components such as calcium, iron, magnesium, manganese, zinc and the like, belongs to a pure natural green sugar material, and is beneficial to health.

At present, raw materials used for industrially producing the fructo-oligosaccharide mainly comprise jerusalem artichoke, chicory or white granulated sugar, and compared with the raw materials comprising the jerusalem artichoke, the chicory or the white granulated sugar, the fructo-oligosaccharide produced by using the raw sugar as the raw material can ensure that the content of the fructo-oligosaccharide after saccharification is more than or equal to 55 percent, and the product has the special flavor of sugarcane, is rich in various mineral compositions such as calcium, iron, magnesium, manganese, zinc and the like, and has better nutrition and flavor. In the prior art, there is also a method for preparing raw material of brown sugar, such as fructo-oligosaccharide prepared from brown sugar disclosed in chinese patent document CN108330150A, which is prepared by the following steps: (1) adding immobilized fructosyltransferase into brown sugar solution for conversion reaction to obtain syrup; (2) filtering and separating the syrup; (3) concentrating and sterilizing the filtered and separated syrup to obtain the syrup. The method has the advantages that the brown sugar has darker color and higher ash content, and if the industrial production is carried out, the burden of decolorization and ion exchange is heavy, the production process for preparing fructo-oligosaccharide by using raw sugar as a raw material is simpler, and the color of syrup is brighter. In addition, CN107354184A discloses a preparation method of fructo-oligosaccharide, which comprises the steps of adding liquid strains into a sucrose solution obtained by sucrose and water, adjusting the pH value of the solution to 4-7 by using a buffer solution, adding zinc chloride, uniformly stirring, fermenting under the irradiation of ultraviolet light, removing bacteria from a fermentation end product, decolorizing, refining and concentrating to obtain the fructo-oligosaccharide. The method adopts self-made liquid strains, has complex operation process, introduces a large amount of inorganic salts in the reaction process, and has heavy ion exchange burden if industrial production is carried out. The production process for preparing the fructo-oligosaccharide by taking the raw sugar as the raw material is simpler, a certain flavor of the sugarcane and rich mineral elements are reserved, and the production cost is lower compared with that of taking white granulated sugar and the like as the raw materials.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a method for preparing fructo-oligosaccharide by using raw sugar as a raw material. The content and the function of the fructo-oligosaccharide prepared by taking the raw sugar as the raw material can reach the level of the fructo-oligosaccharide prepared by taking the white granulated sugar as the raw material, and certain flavor and rich mineral elements of the sugarcane are reserved, so that the sugarcane is more nutritional and healthy. Compared with white granulated sugar and the like as raw materials, the production cost is lower.

The technical scheme of the invention is as follows:

a method for preparing fructo-oligosaccharide from raw sugar comprises the following steps:

(1) preparing a raw sugar solution with the concentration of 30-70 wt%, and adding fructosyltransferase into the prepared raw sugar solution for saccharification for 4-100 h to obtain a saccharification solution;

(2) decoloring, ultrafiltering and vacuum concentrating the saccharified liquid obtained in the step (1) to obtain liquid fructo-oligosaccharide;

(3) and (3) carrying out chromatographic separation, concentration and drying on the liquid fructo-oligosaccharide obtained in the step (2) to obtain solid fructo-oligosaccharide.

Preferably, according to the present invention, in the step (1), the concentration of the raw sugar solution is 40 wt% to 60 wt%.

Preferably, in step (1), the fructosyltransferase is added in an amount of 0.3 to 3L/t dry basis.

Preferably, in step (1), the saccharification conditions are: the temperature is 40-75 ℃, the pH is 5.0-7.0, and the time is 10-80 h.

Preferably, in the step (2), a granular activated carbon column with the diameter of 10-30 meshes is used for decoloring, the temperature of the granular activated carbon column is 70-80 ℃, the flow rate of the saccharifying liquid is 2-3 BV, and the decoloring time is 0.5-1.0 h.

Preferably, in the step (2), an ultrafiltration membrane with a membrane molecular weight of 1 w-10 w Da is used, and the operating pressure is 0.1-1.0 MPa and the temperature is 30-50 ℃.

Preferably, in the step (2), the vacuum concentration is carried out at an operating pressure of 0.1-1.0 MPa and a temperature of 65 ℃, and the mass percentage of solids in the obtained liquid fructo-oligosaccharide is 60-75%.

Preferably, according to the present invention, in the step (3), the chromatographic separation conditions are: the operating pressure is 0.1-1.0 MPa, the temperature is 30-50 ℃, and the mass percentage of fructo-oligosaccharide in the liquid fructo-oligosaccharide after chromatographic separation is 70-95%.

Preferably, in step (3), the drying is spray drying or belt drying.

The invention has the following beneficial effects:

(1) the invention uses the raw sugar as the raw material to prepare the fructo-oligosaccharide, breaks through the current production mode of producing the fructo-oligosaccharide by using the jerusalem artichoke, the chicory or the white granulated sugar as the raw material in the industry, uses the raw sugar with lower cost to replace, and greatly reduces the cost of industrial production.

(2) The fructo-oligosaccharide prepared by the invention can reach the level of the fructo-oligosaccharide prepared by the raw materials such as white granulated sugar in the aspect of functions, and the fructo-oligosaccharide product prepared by the invention keeps certain sugarcane flavor, and the sugarcane flavor is stronger.

(3) The preparation method adopted by the invention has simple process and convenient operation, and in the refining process, the ultrafiltration process replaces the currently common ion exchange process, thereby reducing the loss, improving the yield of the fructo-oligosaccharide, and simultaneously adopting the ultrafiltration to reserve rich mineral elements contained in the raw sugar, thereby being more nutritional and healthy.

The specific implementation mode is as follows:

the technical solution of the present invention is described in detail by the following specific examples, but the scope of the present invention is not limited thereto.