CN115678925A - Preparation method of calcium propionate - Google Patents
Preparation method of calcium propionate Download PDFInfo
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- CN115678925A CN115678925A CN202211344889.6A CN202211344889A CN115678925A CN 115678925 A CN115678925 A CN 115678925A CN 202211344889 A CN202211344889 A CN 202211344889A CN 115678925 A CN115678925 A CN 115678925A
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Abstract
The invention provides a preparation method of calcium propionate, which comprises the following steps: s1: performing slant culture on the activated propionibacterium and preparing an initial bacterial suspension; s2: preparing an initial culture medium; s3: placing the initial bacterial suspension into an initial culture medium for culturing to obtain a propionibacterium bacterial suspension; s4: putting the propionibacterium suspension into a fermentation tank, adding a fermentation culture medium into the fermentation tank for fermentation to obtain fermentation propionic acid, and S5: filtering propionic acid produced by fermentation by adopting an anion permeable membrane to obtain propionate, reacting anion with calcium hydroxide to obtain a calcium propionate solution; s6: and (3) carrying out evaporative crystallization on the calcium propionate solution to obtain calcium propionate crystals.
Description
Technical Field
The invention relates to the technical field of preparation of food additives, in particular to a preparation method of calcium propionate.
Background
The safe and reliable food and feed additive approved by the World Health Organization (WHO) and the Food and Agriculture Organization (FAO) of the United nations is a safe, efficient and broad-spectrum antibacterial and mildewproof agent in the aspects of food industry, feed processing, pharmaceutical preparation, skin care products and the like.
The calcium propionate has wide antibacterial effect on mould, yeast, bacteria and the like, is widely applied, and is safe and effective. The preservative has the characteristics of excellent preservative and fresh-keeping functions, good solubility, convenient use and high content of available calcium, so that the calcium propionate is more beneficial to human bodies compared with the traditional preservative. Calcium propionate, like other fatty acids, is metabolized and absorbed by human and livestock, and supplies calcium necessary for human and livestock, which is an advantage that other mildewcides cannot.
There are two main ways of calcium propionate production at present: the preparation of calcium propionate by producing propionic acid by a biological fermentation method and the preparation of calcium propionate by producing propionic acid by organic chemical oxidation synthesis.
The biological fermentation method has become a main mode for producing calcium propionate due to the advantages of safety, reliability, low cost, simple and easily obtained and stable raw materials and the like, at present, propionic acid is prepared by fermenting propionibacterium by taking glucose as a substrate or glycerol as a fermentation substrate, a calcium propionate solution is prepared by adding a calcium source, and a calcium propionate powder finished product is prepared by atomization and drying. The problems encountered in the preparation of propionic acid by a biological fermentation method are mainly reflected in that propionic acid generated in the fermentation process cannot be separated in time, and even if alkali is added in the fermentation process to neutralize propionic acid, propionic acid roots still exist in fermentation liquor, so that the subsequent growth and propagation of propionic acid bacteria and continuous fermentation are greatly influenced, and the problems of low yield, low purity, high cost and the like are caused; in addition, after the fermentation by the current biological fermentation method is finished, impurities such as mycelium and the like in the fermentation liquor containing propionic acid need to be removed through a microfiltration membrane (ceramic membrane and the like), and then the propionic acid is concentrated and distilled through a nano membrane, and then a calcium source is added to generate calcium propionate. The process is complex, the energy consumption of the atomization drying process is high, and the propionic acid residue in the distilled waste liquid is high, so that the problems of high production cost, long production period and the like are caused.
The chemical synthesis method for producing propionic acid has the advantages of large investment of equipment, high energy consumption, expensive catalyst, high pollution, high production safety requirement and high cost, and flammable and explosive organic reagent raw materials such as ethylene, ethanol and the like are required to be used.
Disclosure of Invention
In order to solve the above technical problems, the present invention provides 1 a method for preparing calcium propionate, comprising the steps of:
s1: performing slant culture on the activated propionibacterium and preparing an initial bacterial suspension;
s2: preparing an initial culture medium, wherein the culture medium comprises 2% of glucose, 1% of sucrose, 2.5% of peptone, 5.15% of yeast extract and 89.35% of drinking water, and the pH value of the culture medium is 7.0-8.0;
s3: placing the initial bacterial suspension into an initial culture medium for culturing to obtain a propionibacterium bacterial suspension;
s4: putting the propionibacterium suspension into a fermentation tank, and adding a fermentation culture medium to perform fermentation to obtain fermentation propionic acid, wherein the fermentation culture medium comprises 10% of glucose, 1% of peptone, 2% of yeast extract, 0.1% of Na2HPO4, 0.1% of MgSO4 7H2O, 0.05% of Tween 80 and 86.75% of drinking water or purified water, and the pH of the fermentation culture medium is 7.0-8.0;
s5: filtering propionic acid produced by fermentation by adopting an anion permeable membrane to obtain propionate, reacting anion with calcium hydroxide to obtain a calcium propionate solution;
s6: evaporating and crystallizing the calcium propionate solution to obtain calcium propionate crystals
Further, the peptone is soy protein.
Wherein, in S4, the fermentation time is 144H, and in the fermentation process, the fermentation liquor is stirred for 10mins at the speed of 10 revolutions per minute every 12H of fermentation.
Wherein, after 48H and 96H fermentation, a sterile 50% glucose aqueous solution is quantitatively fed-batch, and 2% sodium hydroxide is used for adjusting the pH value of the fermentation to 7.0-8.0.
In S5, a material pump is utilized to pump the fermentation liquor to a propionic acid diffusion permeation chamber in a permeation diffusion device, the feeding speed is controlled to be 1/8 of the volume of the fermentation liquor per hour, the pressure of the diffusion permeation chamber is controlled to be 0.4-0.8 MPa, meanwhile, 0.1% of calcium hydroxide solution is introduced into a propionic acid receiving chamber of the permeation diffusion device, the speed is 1/16 of the volume of the fermentation liquor per hour, and when the fermentation liquor passes through the diffusion chamber, propionate is permeated and diffused into the calcium hydroxide solution on the other side through an anion exchange permeation membrane under the action of osmotic pressure and pump pressure to generate the calcium propionate solution.
Wherein, the fermentation liquor which is left in the diffusion and permeation chamber after permeation returns to the fermentation tank to be continuously fermented to produce the propionic acid.
Furthermore, the anion diffusion permeable membrane is a quaternary ammonium salt type anion exchange membrane with the aperture of 100 Da-300 d.
In S6, adjusting the pH value of the dialyzed calcium propionate solution to 10-11, and clarifying the calcium propionate solution by fine filtration and turbidity removal; concentrating the clear calcium propionate solution to more than 15% by using a reverse osmosis membrane, and performing vacuum evaporation concentration crystallization, wherein the concentration is more than 40% by vacuum evaporation, the vacuum pressure is-0.06 to-0.08 Mpa, and the temperature is 60-80 ℃; adding a proper amount of finished calcium propionate crystals, and continuing to evaporate the calcium propionate solution in vacuum until more than 98% of calcium propionate crystals are separated out.
Further, the precipitated calcium propionate crystals are tiled, dried in vacuum at 70-80 ℃ for 30 minutes, and crushed to obtain calcium propionate crystal powder.
The invention has the beneficial effects that:
the invention adopts the conventional method that glucose is used as a substrate, and propionic acid is produced by fermenting propionibacterium propionicum. In the fermentation process, the fermentation liquor is periodically pumped into a diffusion dialysis device, and the propionic acid in the fermentation liquor is periodically dialyzed into 0.1 percent of calcium hydroxide solution on the other side through the diffusion effect, the convection mass transfer effect, the ion migration special transfer effect and the pumping pressure effect of an anion exchange membrane to directly generate the calcium propionate. The propionic acid generated in the fermentation process can be separated from the fermentation liquor at regular time through the permeable membrane, so that the influence of the propionic acid on the strains in the fermentation liquor is fundamentally solved, and the fermentation yield and the purity of the propionic acid are increased.
The post-treatment process of the finally obtained mixed feed liquid of the calcium propionate and the calcium hydroxide is simple, the calcium propionate solution is clarified through fine filtration, the calcium propionate solution is concentrated through a reverse osmosis membrane, a finished product is obtained through vacuum evaporation, crystallization and drying, the whole evaporation process is evaporated in a vacuum state, the evaporation temperature is low at 60-80 ℃, the energy consumption is low, the product purity is high, the yield is high, and compared with the processes of microfiltration, membrane concentration, propionic acid distillation, calcium hydroxide or calcium carbonate addition reaction for producing the calcium propionate, fine filtration clarification, atomization drying and the like in the prior art, the process is simpler.
The invention adopts the glucose which is derived from the wheat and the corn starch as the substrate to ferment and produce the calcium propionate, so that the calcium propionate product produced by the invention can better meet the requirements of natural food and European and American cleaning labels.
Drawings
Fig. 1 is a schematic view of a part of the structure of an apparatus used in the embodiment of the present invention.
FIG. 2 is a schematic diagram of the construction of an osmotic diffusion device used in an embodiment of the present invention.
Detailed Description
Embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways as defined and covered by the claims.
A preparation method of calcium propionate comprises the following steps:
s1: performing slant culture on activated propionibacterium (China center for culture Collection of microorganisms and Consumer accession number: 1.2230) and preparing into initial bacterial suspension;
s2: preparing an initial culture medium, wherein the culture medium comprises 2% of glucose, 1% of sucrose, 2.5% of peptone (preferably soy protein), 5.15% of yeast extract and 89.35% of drinking water, and the pH value of the culture medium is 7.0-8.0;
s3: placing the initial bacterial suspension into an initial culture medium for culturing to obtain a propionibacterium bacterial suspension; in this embodiment, three-stage culture is preferably employed; the specific situation is as follows:
first-stage: the preferred strain for slant culture is prepared into 5ml of bacterial suspension, which is respectively inoculated into 500ml of sterilized culture medium of 6 strains, and then anaerobic culture is carried out for 24H at 30 ℃.
And (2) second stage: a total of 2L of the preferred 4 500ml primary seed solutions were inoculated into 50L of sterilized medium in a mini-seed tank and anaerobically cultured at 30 ℃ for 24H.
Third-stage: and inoculating 50L of the secondary seed solution L into 500L of sterilized culture medium in a seeding tank, and carrying out anaerobic culture for 24H at the temperature of 30 ℃ to obtain 500L of a tertiary propionic acid producing bacillus suspension.
S4: putting the propionibacterium suspension into a fermentation tank, and adding a fermentation culture medium to perform fermentation to obtain fermentation propionic acid, wherein the fermentation culture medium comprises 10% of glucose, 1% of peptone (preferably soybean protein), 2% of yeast extract, 0.1% of Na2HPO4, 0.1% of MgSO4 7H2O, 0.05% of Tween 80 and 86.75% of drinking water or purified water, and the pH of the fermentation culture medium is 7.0-8.0; wherein the fermentation time is 144H, and in the fermentation process, the fermentation liquid is stirred for 10mins at the speed of 10 revolutions per minute every 12H of fermentation. In the fermentation process, the regular slow stirring ensures that the strain can more fully digest and utilize the glucose, and the regular slow stirring is needed to ensure the uniformity of the fermentation liquid and the fermentation efficiency because the local propionic acid is possibly generated at a higher speed to cause a high reduction speed of the local pH and influence the continuous propagation and growth of the subsequent strain in the fermentation process.
After 48H and 96H of fermentation, sterile 50% glucose aqueous solution is quantitatively fed, and the pH of the fermentation is adjusted to 7.0-8.0 by using 2% sodium hydroxide.
S5: filtering propionate out by an anion permeable membrane from the fermentation propionic acid, reacting with calcium hydroxide to obtain a calcium propionate solution;
specifically, in S5, as shown in fig. 1 and 2, the material pump is used to pump the fermentation liquid into a propionic acid diffusion permeation chamber (the feeding direction is from bottom to top) of the permeation diffusion device, the feeding speed is controlled at 1/8 of the volume of the fermentation liquid per hour, the pressure in the diffusion permeation chamber is controlled at 0.4-0.8 Mpa, meanwhile, 0.1% calcium hydroxide solution is introduced into a propionic acid receiving chamber of the permeation diffusion device (the direction is opposite to the direction of the fermentation liquid from top to bottom), the speed is 1/16 of the volume of the fermentation liquid per hour, and when the fermentation liquid passes through the diffusion chamber, the propionate is permeated and diffused into the calcium hydroxide solution on the other side through an anion exchange permeation membrane under the action of osmotic pressure and pumping pressure to generate a calcium propionate solution.
Specifically, the fermentation liquor which is left in the diffusion permeation chamber after permeation returns to the fermentation tank to be continuously fermented to produce propionic acid;
specifically, the anion diffusion permeable membrane is a quaternary ammonium salt type anion exchange membrane with the aperture of 100 Da-300 d.
S6: and (3) carrying out evaporative crystallization on the calcium propionate solution to obtain calcium propionate crystals.
Specifically, in S6, adjusting the pH value of the dialyzed calcium propionate solution to 10-11, and clarifying the calcium propionate solution by fine filtration and turbidity removal; concentrating the clarified calcium propionate solution to more than 15% by using a reverse osmosis membrane, and performing vacuum evaporation and concentration crystallization, wherein the concentration is more than 40% by vacuum evaporation, the vacuum pressure is-0.06 to-0.08 Mpa, and the temperature is 60-80 ℃; adding a proper amount of finished calcium propionate crystals, and continuing to evaporate the calcium propionate solution in vacuum until more than 98% of calcium propionate crystals are separated out.
In actual production, three times of dialysis are usually performed, and the specific operations are as follows:
(1) first diffusion dialysis: after fermenting for 40 hours, pumping the fermentation liquor to a propionic acid diffusion permeation chamber (the feeding direction is from bottom to top) in a permeation diffusion device by using a material pump, controlling the feeding flow at 600-700L/H, and controlling the pressure of the diffusion chamber at 0.6Mpa; at the same time, 0.1 percent of calcium hydroxide solution is introduced into the propionic acid receiving chamber (the direction is opposite to the direction of fermentation liquid from top to bottom), the temperature is 30 ℃, and the flow rate is 300-350L/H. Diffusion dialysis of propionic acid 8H; monitoring the pH value of the mixed solution of calcium propionate and calcium hydroxide on line, supplementing a proper amount of 20% calcium hydroxide emulsion into a liquid storage tank in time when the pH value is lower than 9, continuously stirring to maintain the pH value of the mixed solution of the liquid storage tank at 10-11, and simultaneously cooling with cooling water to maintain the temperature of the mixed solution of the liquid storage tank at 28-32 ℃;
(2) first feeding of glucose: fermenting for 48H, and quickly adding 1000L of 50% glucose aqueous solution subjected to fine filtration and sterilization by 0.22um after the first diffusion dialysis is finished; adjusting the pH value of the fermentation to 7.0-8.0 by using 2% sodium hydroxide; during feeding, stirring at a low speed of 10 r/min to make the fermentation liquor uniform, stopping stirring after feeding, and continuing fermentation to produce propionic acid.
(3) And (3) second diffusion dialysis: after 88H fermentation, the second diffusion dialysis 8H is carried out according to the procedure in step (1).
(4) And (3) feeding glucose for the second time: after the end of the second diffusion dialysis for fermentation 96H, 1000L of sterile 50% glucose aqueous solution was fed in the last step according to step (2).
(5) And (3) third diffusion dialysis: after 144H fermentation, diffusion dialysis was performed according to step (1); repeatedly dialyzing for 24H, circulating for about 3 times of fermentation liquor volume, and separating more than 80% propionic acid from the fermentation liquor;
(6) 1000L of purified water is used as a propionic acid receiving solution instead of the mixed solution of calcium hydroxide and calcium propionate, and the flow rate is reduced to 1/8 of the flow rate of the calcium hydroxide solution in the step (1). And (2) repeatedly dialyzing for 24H according to the flow of the step (1), circulating the volume which is about 3 times of the volume of the fermentation liquor, properly adjusting the pressure to 0.8Mpa, and increasing the action of the pump pressure to enable the propionate to permeate the exchange membrane more easily. The residual propionic acid in the fermentation liquor can be reduced to below 0.1 percent by the step.
(7) About 8000L of the circulating dialysate of (1) \ (3) \ (5) and about 2000L of the dialysate of the purified water of (6) are mixed to have a total volume of about 10000L and a calcium propionate concentration of about 6-8%, and the pH is adjusted to 10-11 with calcium hydroxide.
Further, the precipitated calcium propionate crystals are tiled, dried in vacuum at 70-80 ℃ for 30 minutes, and crushed to obtain calcium propionate crystal powder.
The invention has the beneficial effects that:
1) The invention adopts the conventional method that glucose is used as a substrate and propionic acid is produced by fermenting propionibacterium propionicum. In the fermentation process, the fermentation liquor is periodically pumped into a diffusion dialysis device, and the propionic acid in the fermentation liquor is periodically dialyzed into 0.1 percent of calcium hydroxide solution on the other side through the diffusion effect, the convection mass transfer effect, the ion migration special transfer effect and the pumping pressure effect of an anion exchange membrane to directly generate the calcium propionate. The propionic acid generated in the fermentation process can be separated from the fermentation liquor at regular time through the permeable membrane, so that the influence of the propionic acid on the strains in the fermentation liquor is fundamentally solved, and the fermentation yield and the purity of the propionic acid are increased.
2) The post-treatment process for finally obtaining the calcium propionate and calcium hydroxide mixed feed liquid is simple, the calcium propionate solution is clarified through fine filtration, the calcium propionate solution is concentrated through a reverse osmosis membrane, a finished product is obtained through vacuum evaporation, crystallization and drying, the whole evaporation process is evaporated in a vacuum state, the evaporation temperature is low at 60-80 ℃, the energy consumption is low, the product purity is high, the yield is high, and compared with the multi-step processes of microfiltration, membrane concentration, propionic acid distillation, calcium propionate production through reaction of adding calcium hydroxide or calcium carbonate, atomization drying after fine filtration and clarification and the like in the prior art, the post-treatment process is simpler.
3) The invention adopts the glucose which is derived from the wheat and the corn starch as the substrate to ferment and produce the calcium propionate, so that the calcium propionate product produced by the invention can better meet the requirements of natural food and European and American cleaning labels.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. The preparation method of calcium propionate is characterized by comprising the following steps:
s1: performing slant culture on the activated propionibacterium and preparing an initial bacterial suspension;
s2: preparing an initial culture medium, wherein the culture medium comprises 2% of glucose, 1% of sucrose, 2.5% of peptone, 5.15% of yeast extract and 89.35% of drinking water, and the pH value of the culture medium is 7.0-8.0;
s3: placing the initial bacterial suspension into an initial culture medium for culturing to obtain a propionibacterium bacterial suspension;
s4: putting the propionibacterium suspension into a fermentation tank, and adding a fermentation medium for fermentation to obtain fermentation propionic acid, wherein the fermentation medium comprises 10 percent of glucose, 1 percent of peptone, 2 percent of yeast extract, 0.1 percent of Na2HPO4, 0.1 percent of MgSO4 7H2O, 0.05 percent of Tween 80 and 86.75 percent of drinking water or purified water, and the pH of the fermentation medium is 7.0-8.0;
s5: filtering propionic acid produced by fermentation by adopting an anion permeable membrane to obtain propionate, reacting anion with calcium hydroxide to obtain a calcium propionate solution;
s6: and (3) carrying out evaporative crystallization on the calcium propionate solution to obtain calcium propionate crystals.
2. The method of claim 1, wherein the calcium propionate is prepared by: the peptone is soybean protein.
3. The method of claim 1, wherein the calcium propionate is prepared by: in S4, the fermentation time is 144H, and in the fermentation process, the fermentation liquor is stirred for 10mins at the speed of 10 revolutions per minute every 12H of fermentation.
4. The method of claim 3, wherein the calcium propionate is prepared by: after 48H and 96H of fermentation, sterile 50% glucose aqueous solution is quantitatively fed, and the pH of the fermentation is adjusted to 7.0-8.0 by using 2% sodium hydroxide.
5. The method of claim 1, wherein the calcium propionate is prepared by: in S5, a material pump is utilized to pump the fermentation liquor to a propionic acid diffusion and permeation chamber in the permeation and diffusion device, the feeding speed is controlled to be 1/8 of the volume of the fermentation liquor per hour, the pressure of the diffusion and permeation chamber is controlled to be 0.4-0.8 Mpa, meanwhile, 0.1% of calcium hydroxide solution is introduced into a propionic acid receiving chamber of the permeation and diffusion device, the speed is 1/16 of the volume of the fermentation liquor per hour, and when the fermentation liquor passes through the diffusion chamber, propionate is permeated and diffused into the calcium hydroxide solution on the other side through an anion exchange and permeation membrane under the action of osmotic pressure and pump pressure to generate the calcium propionate solution.
6. The method of claim 5, wherein the step of preparing calcium propionate comprises: wherein, the fermentation liquor which is left in the diffusion and permeation chamber after permeation returns to the fermentation tank to be continuously fermented to produce the propionic acid.
7. The method of claim 5, wherein the calcium propionate is prepared by: the anion diffusion permeable membrane is a quaternary ammonium salt type anion exchange membrane, and the aperture is 100 Da-300 d.
8. The method of claim 1, wherein the step of preparing calcium propionate comprises: in S6, adjusting the pH value of the dialyzed calcium propionate solution to 10-11, and clarifying the calcium propionate solution by fine filtration and turbidity removal; concentrating the clarified calcium propionate solution to more than 15% by using a reverse osmosis membrane, and performing vacuum evaporation and concentration crystallization, wherein the concentration is more than 40% by vacuum evaporation, the vacuum pressure is-0.06 to-0.08 Mpa, and the temperature is 60-80 ℃; adding a proper amount of finished product calcium propionate crystals, and continuing to evaporate the calcium propionate solution in vacuum until more than 98% of calcium propionate crystals are separated out.
9. The method of claim 8, wherein the calcium propionate is prepared by:
and flatly paving the precipitated calcium propionate crystals, drying the crystals for 30 minutes at 70-80 ℃ in vacuum, and crushing the crystals to obtain calcium propionate crystal powder.
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