CN101818182A - Method for extracting high-viscosity oat polysaccharide by using naked oat bran as raw material - Google Patents

Abstract

The invention provides a method for extracting high-viscosity oat polysaccharide by using naked oat bran as a raw material. In the method, the naked oat bran serving as the raw material undergoes extrusion treatment, ethanol pre-treatment, multiple extractions by using water as an extraction solvent, mixing of extraction solution, addition of enzymes for starch degradation, isoelectric point deproteinization or protease hydrolysis method deproteinization, vacuum condensation, ethanol precipitation, standing, pumping filtration, collection of precipitates and freeze drying or hot air drying to form the oat polysaccharide. The viscosity of the oat polysaccharide obtained by the method is 2.2 to 2.8 times that of the common oat polysaccharide.

Description

With the naked oats wheat bran is the method that raw material extracts high viscosity oat polysaccharide

Technical field

The invention belongs to oat deep process technology field, especially a kind of is the method that raw material extracts high viscosity oat polysaccharide with the naked oats wheat bran.

Background technology

Food fibre (Dietary Fiber) is a kind of natural organic high-molecular compound, it is the non-starch based polysaccharide that is polymerized by the monose dehydration, can not be decomposed by digestive ferment in the human body, but can be by microbiological deterioration in the large intestine and utilization, be to keep a healthy indispensable class glucide, itself have water holding, hold oil, features such as strong water-swelling and strong adsorptive power.

The oat polysaccharide is the existence form after the water-soluble dietary fibre beta-glucan extracts in the oat, because beta-glucan is the important component of oat albuminous cell wall, so often extract from oat bran.The molecular structure of avenabeta glucosan is widely studied, existing known be D-glucose with β-(1,3) and linear polysaccharide that β-(1,4) glycosidic link is formed by connecting, the ratio of two kinds of glycosidic links is roughly 7: 3; β in the avenabeta glucosan-(1,3) and β-(1,4) glycosidic link distribute neither complete ordering, also non-unordered fully, wherein β-single existence of (1,3) key, β-(1,4) key then 2,3 connect and exist, maximum can reach 14 dextran units.Beta-glucan is not a material independently, and and protein, piperylene etc. be closely linked.

The oat polysaccharide that extracts gained from oat bran can be water-soluble, acid and diluted alkaline, be insoluble to ethanol, but its solvability influenced by oat polyoses grain size, 1,4 beta-glucanase activity, temperature, pH and medium ionic.Highly purified oat polysaccharide is a white, tasteless complete neutrality, its compound structure and action function are more satisfactory, do not contain gluten and phytinic acid, heavy metal and agricultural chemicals residual few do not contain microorganism yet, more stable, be subjected to the influence of temperature and pH hardly, have high viscosity characteristic, stronger retentiveness, good emulsifying and stable emulsifying performance, fibre network is stable.

Rheological characteristics is determined by the shape in the structure of beta-glucan, molecular size and the solution.K.Autio etc. have studied the rheological characteristics of avenabeta glucosan under conditions such as differing temps, concentration, shearing rate, studies show that the flow curve of 0.2-1.56% beta-glucan meets the Power-law model, the pseudoplastic fluid of performance shear shinning.Doublier and Wood research is thought, contains 80% beta-glucan oat gum, shows as random curling behavior in solution, and points out, is higher than at 0.3% o'clock in concentration, and viscosity and concentration are height correlations.The research of Kulicke shows then that when concentration is higher than threshold concentration viscosity and concentration present index rising relation.I.A.Nnann etc. have compared oat gum and other food colloids viscous behavior and colloid property in different shear rate, shown avenabeta glucosan can with melon glue etc. other food colloid is composite is applied in the foodstuffs industry.

The relative molecular mass of beta-glucan and concentration also can have influence on gelation, and relative molecular mass reduces to separate party with beta-glucan descends stickiness, and gellifying property increases; The easier formation gel of the beta-glucan that the beta-glucan that relative molecular mass is low is higher than relative molecular mass.The gelation of polysaccharide can be widely used in influencing in the food such as jam, pudding the quality of food.

The application of oat polysaccharide and its viscosity are closely related, and oat polysaccharide extractive technique is in the past only paid attention to the extraction yield of oat polysaccharide, and do not pay close attention to the viscosity variation of oat polysaccharide.Therefore, be necessary to study, develop the production technology of high viscosity oat polysaccharide at the relation of naked oats polysaccharide working method and the variation of its viscosity.

By retrieval, find two pieces of patent documentations related to the present invention, a kind of method (CN101558845) of comprehensively extracting oat starch, protein powder, beta-glucan from oat bran of the first mainly may further comprise the steps: 1. oat bran immersion, defibrination; 2. separation of starch from slurry; 3. liquid ingredient adjust pH precipitation is separated out avenin; 4. filtrate isolating beta-glucan; 5. the Separation ﹠ Purification of oat starch; 6. the purification of avenin.It two is a kind of methods (CN1869077) of extracting avenabeta glucosan, comprises the steps: 1) oat bran is added water stir under 50-60 ℃, regulate pH 8-10; 2) add proteolytic enzyme at the 45-60 ℃ of albumen of handling down in the hydrolysis oat bran; 3) add α-Dian Fenmei and handle down, filter, obtain clarified liq at 80 ℃; 4) adopting molecular weight cut-off is the ultrafiltration membrance filter of 30000-50000Da, obtains beta-glucan solution, and lyophilize obtains the beta-glucan product.

Above-mentioned two pieces of patent documentations mostly are the technological improvements on the oat polysaccharide yield, with the technical scheme of present patent application in essence different are arranged.

Summary of the invention

The objective of the invention is to overcome the deficiencies in the prior art part, provide a kind of from through extracting the method have than the oat polysaccharide of high viscosity the pretreated naked oats wheat bran of extruding, the viscosity of the oat polysaccharide that obtains with this method is 2.2～2.8 times of common oat polysaccharide viscosity.

The objective of the invention is to be achieved through the following technical solutions:

A kind of is the method that raw material extracts high viscosity oat polysaccharide with the naked oats wheat bran, and step is:

(1) extruding pre-treatment: the naked oats wheat bran, the adjusting moisture content is 25%-45%, extrusion temperature is (110～120 ℃)-(130～145 ℃)-(160～180 ℃);

(2) ethanol pre-treatment: the aqueous ethanolic solution that adds 50%～80% (V/V) through the naked oats wheat bran of extrusion process, the feed liquid ratio is 1: (3～4) g/v, in 60 ℃～80 ℃ insulation 10-40min, abandoning supernatant, lower floor's insolubles repeats last time and operates 2～3 times, obtains the naked oats wheat bran of pre-treatment;

(3) water extraction: water is (6～10) with the ratio of the naked oats wheat bran of process pre-treatment: 1 (mL: g), in 70～90 ℃ of insulation 80～120min, filter, collect filtrate, insolubles repeats aforesaid operations 2 times, merging filtrate, and vacuum concentration is to 1/3rd of original volume;

(4) starch removes: every 1000L filtrate adds the heat-resisting amylase of 3000U～6000U, is heated to more than 95 ℃ to keep 10～30min, is cooled to 60 ℃, adds Glycosylase 3000U～6000U, keeps 10～30min;

(5) iso-electric point removes protein: the pH value of extracting solution is adjusted to 4.5, leaves standstill 2～4h in 0～30 ℃, and centrifugal or filter, collect supernatant liquor or filtrate, the pH that regulates this solution is 6.0～7.0, vacuum concentration is to 1/2nd of original volume;

(6) vacuum concentration: vacuum tightness＜0.1MPa is concentrated to extracting solution more than 10% under 45～65 ℃;

(7) ethanol sedimentation: add down slowly ethanol in feed liquid in agitation condition, make alcohol concn greater than 70%, leave standstill 6～24h in 0～30 ℃, filter or centrifugation, collect solid matter, drying promptly gets the oat polysaccharide.

And, iso-electric point in the described step (5) removes protein and adopts the protease hydrolysis method to remove protein to substitute, be the proteolytic enzyme that every 1000L filtrate adds 10000U～400000U, in 50～60 ℃ of maintenance 20～40min, vacuum concentration is to 1/2nd of original volume.

Advantage of the present invention and positively effect are:

The present invention is a raw material with the naked oats wheat bran, passes through extrusion process and ethanol pre-treatment successively, and then extracts high viscosity oat polysaccharide, and the viscosity of the oat polysaccharide that obtains with this method is 2.2～2.8 times of common oat polysaccharide viscosity.

Embodiment

Below in conjunction with embodiment, the present invention is further described, and following embodiment is illustrative, is not determinate, can not limit protection scope of the present invention with following embodiment.

Specific examples of the present invention:

1, take by weighing 1000kg naked oats wheat bran, add 350kg-600kg water, making moisture content is 25%-45%, stir, and three sections extruding, its temperature is: (110～120 ℃)-(130～145 ℃)-(160～180 ℃)).

(1) extruding pre-treatment: naked oats wheat bran, extrusion temperature are (110～120 ℃)-(130～145 ℃)-(160～180 ℃);

2, the aqueous ethanolic solution that adds 50%～80% (V/V) through the naked oats wheat bran of above-mentioned processing treatment again, the feed liquid ratio is 1: (3～4) (g naked oats wheat bran/v ethanolic soln), in 60 ℃～80 ℃ insulation 10-40min, abandoning supernatant, lower floor's insolubles repeats last time and operates 2～3 times.

3, through the naked oats wheat bran of Ethanol Treatment, ethanol is removed in volatilization, add distilled water, material/liquor ratio is (6～10): 1 (mL distilled water: g naked oats wheat bran), in 70～90 ℃ of insulation 80～120min, filter, collect filtrate, insolubles repeats aforesaid operations 2 times, merging filtrate, and vacuum concentration is to 1/3rd of original volume.

4, concentrated filtrate adds the heat-resisting amylase of 10000U～60000U, heats to more than 95 ℃, and insulation 10～30min is cooled to 60 ℃, adds Glycosylase 10000～60000U, keeps 10～30min.

5, the pH that regulates extracting solution is 4.5,0～30 ℃ and leaves standstill 2～4h, and is centrifugal or filter, and collects supernatant liquor or filtrate, and the pH that regulates this solution is 7.0, and vacuum concentration is to 1/2nd of original volume.

Or extracting solution added the proteolytic enzyme of 60000～4000000U, and keeping 20min～40min in 50 ℃～60 ℃, vacuum concentration is to 1/2nd of original volume.

6,, extracting solution is concentrated to more than 10% under 45～65 ℃ at vacuum tightness＜0.1MPa;

7, under vigorous stirring, in extracting concentrated solution, slowly add ethanol, make concentration of ethanol greater than 70%, leave standstill 6～24h in 0～30 ℃, filter or centrifugation, collect solid matter, lyophilize or warm air drying, the oat polysaccharide.

Claims (2)

1. one kind is the method that raw material extracts high viscosity oat polysaccharide with the naked oats wheat bran, and it is characterized in that: step is:

(1) extruding pre-treatment: the naked oats wheat bran, the adjusting moisture content is 25%-45%, extrusion temperature is (110～120 ℃)-(130～145 ℃)-(160～180 ℃);

(2) ethanol pre-treatment: the aqueous ethanolic solution that adds 50%～80% (V/V) through the naked oats wheat bran of extrusion process, the feed liquid ratio is 1: (3～4) g/v, in 60 ℃～80 ℃ insulation 10-40min, abandoning supernatant, lower floor's insolubles repeats last time and operates 2～3 times, obtains the naked oats wheat bran of pre-treatment;

(3) water extraction: water is (6～10) with the ratio of the naked oats wheat bran of process pre-treatment: 1 (mL: g), in 70～90 ℃ of insulation 80～120min, filter, collect filtrate, insolubles repeats aforesaid operations 2 times, merging filtrate, and vacuum concentration is to 1/3rd of original volume;

(4) starch removes: every 1000L filtrate adds the heat-resisting amylase of 3000U～6000U, is heated to more than 95 ℃ to keep 10～30min, is cooled to 60 ℃, adds Glycosylase 3000U～6000U, keeps 10～30min;

(5) iso-electric point removes protein: the pH value of extracting solution is adjusted to 4.5, leaves standstill 2～4h in 0～30 ℃, and centrifugal or filter, collect supernatant liquor or filtrate, the pH that regulates this solution is 6.0～7.0, vacuum concentration is to 1/2nd of original volume;

(6) vacuum concentration: vacuum tightness＜0.1MPa is concentrated to extracting solution more than 10% under 45～65 ℃;

(7) ethanol sedimentation: add down slowly ethanol in feed liquid in agitation condition, make alcohol concn greater than 70%, leave standstill 6～24h in 0～30 ℃, filter or centrifugation, collect solid matter, drying promptly gets the oat polysaccharide.

2. according to claim 1 is the method that raw material extracts high viscosity oat polysaccharide with the naked oats wheat bran, it is characterized in that: the iso-electric point in the described step (5) removes protein and adopts the protease hydrolysis method to remove protein to substitute, be the proteolytic enzyme that every 1000L filtrate adds 10000U～400000U, in 50～60 ℃ of maintenance 20～40min, vacuum concentration is to 1/2nd of original volume.