A kind of process for purification of raffinose
Technical field
The invention belongs to the deep processing field of cottonseed, be specifically related to a kind of process for purification of raffinose.
Background technology
Raffinose claims raffinose again, is the most well-known a kind of trisaccharide of occurring in nature,, all has the about 2-5wt% of content in cottonseed benevolence in most plant by semi-lactosi, fructose and glucose be combined into.Raffinose belongs to functional oligose, has extensive use at protective foods and pharmaceutical industries, its physiological function mainly contains: 1) raffinose promotes bifidus bacillus propagation, it is the multiplicaiton factor of bifidus bacillus, and bifidus bacillus can be in enteron aisle nutritive substances such as synthesise vitamins B1, B2, B6, B12, nicotinic acid, folic acid, help enhancing body immunizing power, the opposing tumour; 2) raffinose can suppress the growth of spoilage organism such as intestinal bacteria and clostridium perfringens, thus objectionable impuritiess such as the phenol that the metabolism of inhibition spoilage organism produces, ammonia, earthworm diindyl, cadaverine; 3) raffinose is difficult to be absorbed by human consumption, the energy that provides very low (6KJ/g), and have certain sugariness, can be used as functional food additives and in food, use; 4) can stimulate intestines peristalsis because the bifidobacterium fermentation raffinose produces a large amount of short chain fatty acids, increase the wettability of ight soil, and the raised growth by thalline to be keeping certain osmotic pressure, thereby improve bowel movement function, prevent the generation of constipation.
Chinese patent No.00134520.6 discloses a kind of treatment process of cottonseed, comprising extract Oleum Gossypii semen from cotton benevolence, remove gossypol and obtain cottonseed protein from cotton dregs, and the methanol solution recovery evaporation that will extract behind the gossypol obtains byproduct-crude product oligose.Yet, owing to extract in the methanol solution behind the gossypol and contain more impurity, pigment, the crude product oligosaccharide contg that obtains is low, impurity is big, using value is little, this patented technology is in practice, produce the byproduct that obtains behind the dephenolization cottonseed protein and be dropped, not only environment is had pollution, and wasted natural raffinose resource owing to being not used.
In recent years, the comprehensive utilization of cottonseed resource comes into one's own gradually.Existing raffinose is purified several different methods, comprises adopting Acid precipitation, centrifugal, resin absorption, millipore filtration, discoloring agent etc.Chinese patent No.200710098890.4 discloses a kind of production method of cottonseed oligosaccharide, wherein part steps is similar to the processing of patent No.00134520.6 cottonseed, use the method for three grades of dephenolizes, institute's difference be the methanol concentration that uses of each extraction step all not to the utmost institute with, how will adjust methyl alcohol in the practical application and not adjust to suitable concentration also not fully not openly; From its disclosed technical parameter, the content of the oligomeric Icing Sugar middle cotton seed sugar for preparing has only about 30%, and protein content illustrates that then up to 20% impurity wherein is still more.
Chinese patent application CN200810089636.2 discloses a kind of method of extracting raffinose in cotton dregs, wherein pay attention to the process of producing of raffinose coarse fodder, only mention subsequent process simply to raffinose raffinate, raffinose purified detailed step is not provided, by conventional means the raffinose crude extract of described preparation is handled and be difficult to obtain the higher raffinose of purity.
Therefore, the byproduct that deep processing obtains from cotton dregs for cottonseed---crude product raffinose is necessary to make with extra care processing, to improve its economic worth and use value.
Summary of the invention
The method that the purpose of this invention is to provide a kind of refining raffinose can remove harmful gossypol and other impurity by this method, obtains the higher raffinose of purity, for raffinose has been opened up bright prospects in the application in food and medicine field.
To achieve these goals, the invention provides following technical scheme:
A kind of method of refining raffinose comprises step:
1) will carry that to add concentration in the cotton dregs behind the oil be methyl alcohol or the ethanol of 65~95wt%, ℃ leaching is 0.5~1.5 hour in normal temperature~65, obtains containing the methyl alcohol or the alcohol extraction liquid of phenol and raffinose, concentrates, and obtains paste;
2) paste is dissolved in the hot water of 1~1.5 times of weight and obtains slurry, cooling was left standstill 5 hours at least, removed solids or pitch shape thing, obtained fraction;
3) with fraction after filtration, obtain clear liquid, clear liquid leaves standstill at least 24 hours crystallizatioies under 0~10 ℃ temperature, obtain crystallisate I;
4) with heating for dissolving in the ethanolic soln of crystallisate I more than concentration 90wt%, at least 24 hours crystallizatioies are left standstill in cooling under 0~10 ℃ temperature, obtain crystallisate II;
5) with crystallisate II with temperature less than 10 ℃, washing with alcohol more than the concentration 95wt%, drying obtains raffinose.
Wherein, cotton dregs described in the step 1) are to obtain after extracting Oleum Gossypii semen by any means known in the art from cottonseed.For example, can be to carry the wet dregs of rice behind the oil by what disclosed method among the patent CN00134520.6 obtained.
The described methanol extraction liquid that contains phenol and raffinose is to concentrate being no more than under 100 ℃ the temperature, and methanol content is less than 500mg/kg in the paste product that obtains.Concentrate and to use modes such as single vaporization, falling film type evaporation, multiple-effect evaporation or thin film evaporation.
The temperature of hot water step 2) is any number in 50 ℃~100 ℃ scopes, for example 50 ℃, 60 ℃, 70 ℃, 80 ℃, 90 ℃ or 100 ℃; Preferred 70~90 ℃, for example 70 ℃, 80 ℃ or 90 ℃; More preferably 70~80 ℃; The weight ratio of paste and hot water is 1: 1~1: the 1.5 any ratio in the scope, for example can be 1: 1,1: 1.1,1: 1.2,1: 1.3,1: 1.4 or 1: 1.5; Preferred 1.2~1.4; Described slurry leaves standstill and can carry out at normal temperatures.
Filter described in the step 3) and comprise coarse filtration and fine filtering.Coarse filtration is meant by the aperture of 0.04~0.1mm filters the aperture of preferred 0.05~0.08mm, the more preferably from about aperture of 0.06~0.07mm.For example, can preferably adopt the filtering material in 0.053mm, 0.063mm or 0.071mm aperture.Described filtering material is silk screen filter cloth, for example Stainless Steel Cloth or fibers material silk screen preferably.Coarse filtration can adopt technique known to carry out, for example centrifugation apparatus, pumping and filtering device, filtering equipment etc.
Filtrate after the coarse filtration is continued fine filtering, and coarse filtration is meant by the aperture of 0.015~0.02mm and filters that the filtering material in 0.02mm aperture for example can preferably be adopted in the aperture of preferred 0.018~0.02mm.Described filtering material can be band suede filter cloth or the essentially identical silk screen filter cloth in aperture, preferably is with the suede filter cloth.Fine filtering can adopt technique known to carry out, for example centrifugation apparatus, pumping and filtering device, filtering equipment etc., but be good with suction filtration or press filtration.Filtering number of times can be an one or many, and the liquid that obtains behind the fine filtering is the best with the solid shape impurity of transparent nothing.
Heating temperature when dissolving in the step 4) is more than 45 ℃, for example 45~75 ℃, and preferred 50~70 ℃, more preferably 55~65 ℃.The weight ratio of crystallisate I and ethanolic soln is 1: 1~1: 5.Dwell temperature can be a normal temperature.Described normal temperature is meant the envrionment temperature when leaving standstill, and when envrionment temperature was hanged down, crystallization effect was better, preferably in envrionment temperature less than 10 ℃, time of repose greater than 24 hours, obtain more crystallisate.Can adopt the freezing artificial hypothermia's method that waits, make envrionment temperature when leaving standstill between 0~10 ℃, for example can be 1 ℃, 2 ℃, 3 ℃, 5 ℃, 7 ℃, 9 ℃ or 10 ℃; Preferred 0~7 ℃, more preferably 0~3.
Consumption of ethanol when washing in the step 5) more than the described concentration 95wt% and 1~1.5 times of weight of crystallisate II for example can be 1.1,1.2,1.3,1.4,1.5 times of weight of crystallisate II.Washing finishes the post crystallization thing by low temperature (less than 10 ℃) or vacuum or conventional known method drying such as freezing, obtains the crystallisate raffinose at last, and its purity can reach 85%.In addition, other cotton glycan such as clear liquid crystallization once more, last resistates simmer down to wood sugar that return capable of circulation of the mother liquor resistates after the crystallization.
Can remove a large amount of protein, tannin, phytic acid, gossypol pigment and lipid-soluble substance and insoluble solid matter in the cotton dregs by method of the present invention, the raffinose for preparing is faint yellow meal, do not have or little hygroscopic effect arranged, having removed the purity of raffinose in the crude product reaches more than 85%, moisture is less than 5%, but the additive of food, medicine and other fields is made in widespread use.
The present invention has following beneficial effect:
1) adopt comparatively simple physics method, got rid of the interpolation chemical agent, as steps such as acid solution, discoloring agents, ethanolic soln is recyclable, makes whole technological operation easy, and cost reduces;
2) purification obtains highly purified raffinose the cotton dregs after cottonseed is carried oil, for bright prospects have been opened up in the application of raffinose; Solved the liquid waste disposal problem of producing behind Oleum Gossypii semen and the cottonseed protein simultaneously;
3) cotton dregs extract in the residue waste residue behind the raffinose and contain great deal of tannin and phytic acid etc., can further extract or as fermentation fertilizer, make cottonseed obtain comprehensively rationally utilizing, for enterprise brings certain economic benefits.
Description of drawings
Fig. 1 is the process flow sheet of the refining raffinose of the present invention.
Embodiment
Following embodiment is used to further specify the present invention in conjunction with the accompanying drawings, but does not limit the scope of protection of the invention.Unless stated otherwise, used reagent and other experiment materials of the present invention is common commercially available prod.
The preparation of embodiment 1 raffinose
Present embodiment uses the cotton dregs carry behind the oil as raw material, and described cotton dregs can be according to the method production among the Chinese patent No.001345206.Methyl alcohol is reclaimed in the methanol solution evaporation that Chinese patent No.001345206 produces behind the dephenolization cottonseed protein, concentrate, obtain paste, controlled temperature≤100 ℃ when concentrating.In system, recycle methanol content<500mg/kg in the paste after the Methanol Recovery.With paste and hot water by weight 1: 1 in common vessel stirring and dissolving be soup compound, the temperature of hot water is 70 ℃.Soup compound left standstill 5 hours after being cooled to room temperature, removed the solids on upper strata or the throw out of pitch shape thing and lower floor, obtained fraction.
The filter cloth suction filtration (coarse filtration) of fraction by the 0.053mm aperture with after removing partial impurities, then by the band suede filter cloth suction filtration (fine filtering) in 0.015mm aperture, obtained the clear liquid of the solid shape impurity of transparent nothing.Place container to leave standstill the clear liquid behind the fine filtering and made its crystallization in 24 hours at 10 ℃, filter crystallisate I.With crystallisate I and concentration is that the ethanolic soln of 95wt% mixes with weight ratio at 1: 1, is heated to 45 ℃~75 ℃ to dissolving fully, naturally cools to normal temperature, leaves standstill crystallization under 10 ℃, filter, crystallisate II.It is the alcohol immersion washing of 95wt% that crystallisate II is used the concentration less than 10 ℃, and consumption of ethanol is about 1 times of weight of crystallisate during washing.Crystallisate II after the washing is the dry crystallisate that obtains raffinose under low temperature (less than 10 ℃) condition, detects through HPLC (high performance liquid chromatography) method, and its purity is about 85.1%.
The preparation of embodiment 2 raffinoses
Present embodiment uses the cotton dregs carry behind the oil as raw material, and described cotton dregs can be according to the method production among the Chinese patent No.001345206.Ethanol is reclaimed in the ethanol liquid evaporation that Chinese patent No.001345206 produces behind the dephenolization cottonseed protein, concentrate, obtain paste, controlled temperature≤100 ℃ when concentrating.Ethanol reclaims the back and recycle ethanol content<500mg/kg in the paste in system.With paste and hot water by weight 1: 1.5 in common vessel stirring and dissolving be soup compound, the temperature of hot water is 90 ℃.Soup compound is cooled to standing over night after the room temperature, removes the solids on upper strata or the throw out of pitch shape thing and lower floor, obtains fraction.
The filter cloth suction filtration (coarse filtration) of fraction by the 0.1mm aperture with after removing partial impurities, then by the band suede filter cloth suction filtration (fine filtering) in 0.02mm aperture, obtained the clear liquid of the solid shape impurity of transparent nothing.Place container to leave standstill the clear liquid behind the fine filtering and made its crystallization at least in 24 hours at 2 ℃, filter crystallisate I.With crystallisate I and concentration is that the ethanolic soln of 95wt% mixes with weight ratio at 1: 1.5, is heated to 45 ℃~75 ℃ to dissolving fully, naturally cools to normal temperature, leaves standstill crystallization at 2 ℃, filter, crystallisate II.Crystallisate II is used less than after 10 ℃ the soaked in absolute ethyl alcohol washing, and lyophilize obtains the crystallisate of raffinose.Consumption of ethanol is about 1.4 times of crystallisate during washing.In the raffinose crystallisate that obtains, the content of raffinose about 85%.
The preparation of embodiment 3 raffinoses
Present embodiment uses the cotton dregs carry behind the oil as raw material, described cotton dregs can be common high temperature cotton dregs, perhaps according to the method production among the Chinese patent No.001345206, obtain contain wet cake with 85% methyl alcohol 40 ℃ of extractions 1.5 hours down, the extraction liquid evaporation concentration, methyl alcohol is reclaimed in controlled temperature≤100 ℃ when concentrating, and obtain paste, methanol content<500mg/kg in the paste.With paste and hot water by weight 1: 1.2 in common vessel stirring and dissolving be soup compound, the temperature of hot water is 80 ℃.Soup compound is cooled to standing over night after the room temperature, removes the solids on upper strata or the throw out of pitch shape thing and lower floor, obtains fraction.
The filter cloth suction filtration (coarse filtration) of fraction by the 0.071mm aperture with after removing partial impurities, then by the band suede filter cloth suction filtration (fine filtering) in 0.02mm aperture, obtained the clear liquid of the solid shape impurity of transparent nothing.Place container to leave standstill the clear liquid behind the fine filtering and made its crystallization in 24 hours at 5 ℃, filter crystallisate I.With crystallisate I and concentration is that the ethanolic soln of 95wt% mixes with weight ratio at 1: 1.5, is heated to dissolving fully, naturally cools to normal temperature, leaves standstill the 24h crystallization at 5 ℃, filter, crystallisate II.Crystallisate II is used less than after 10 ℃ the soaked in absolute ethyl alcohol washing, and lyophilize obtains the crystallisate of raffinose.Consumption of ethanol is about 1.2 times of crystallisate during washing.The content about 85.3% of raffinose in the cottonseed oligose crystallisate that obtains at last.