The method of obtaining citric acid
(57) Abstract:Method for obtaining citric acid, in which the fermented solution, cleaned with a slurry of bentonite followed by treatment of a solution of a carbon sorbent, taken in an amount of 2.0 to 12.0 g per 1 DM3solution. The amount of sorption time limit 0,30-0,80 cm3/, this provides a reduction in the color and quantity of impurities in the purified solution. 1 C.p. f-crystals, 1 table. The invention relates to the microbiological industry, and comes to cleaning and bleaching fermented environments in directed biosynthesis of citric acid from carbohydrate-containing raw materials.Citric acid is a multifunctional product, and its scope is very diverse. With the growing needs of citric acid in the food industry, we have urgent task of obtaining high-quality liquid citric acid. In accordance with the traditional way of cleaning solutions of citric acid undergo multi-stage, at the stage of precipitation of calcium citrate, the decomposition of sulfuric acid and filtration of the gypsum slurry by adding activated carbon in a solution of citric acid, and is lnyh costs. When using powdered activated carbon requires careful filtering particles from coal, the installation of the control filters and high head pressure during the filtration process. Excessive consumption of coal leads to a significant reduction in the solution of the acid content due to the interaction of acid and minerals coal. In addition, regeneration of spent coal is a long, complex and inefficient process, requiring significant quantities of reagents and energy.Closest /2/ to the proposed method is a method for citric acid, which after fermentation of carbohydrate-containing raw material is cleaned fermented solution, sorbent, which is used as a suspension of activated bentonite in the amount of 2 - 5 g/DM3in terms of dry bentonite solution stand for at least 40 minutes, separating the precipitate, and then filtered through a layer of zeolite, and receive liquid citric acid containing 0.52 g of protein per 100 grams of acid, and 0.04 wt.% ash matter, 2.17 g of residual sugar per 100 grams of acid and which has a light yellow color.When the concentration of, for example, by evaporation, the resulting solution of citric acid also increases coee appearance.The technical result of the invention is to reduce the color and quantity of impurities in fermented citric acid solution while maintaining its content in the solution.The technical result of the invention is achieved in that in a method of producing citric acid, including the fermentation of carbohydrate-containing raw material, cleaning of the fermented solution with a suspension of activated bentonite, subsequent separation of the solution, which after the separation process of a carbon adsorbent with sorption volume of pores in the limit 0,30 - 0,80 cm3/g, taken in an amount of 2.0 to 12.0 g per 1 DM3solution, and as a carbon sorbent used activated carbon fiber material selected from the group including brand material OUT-M, busofit T busofit TM, carbopol.Information confirming the possibility of achieving technical results presented in the examples.In the examples used carbon fiber sorbents produced by the industry, and their quality is TU RB 00204056-076-94 "carbon Sorbent medical OUT-M, TU RB 00204056-108-95 "Activated carbon fiber material Busofit the p.Example 1
Carry out the fermentation of Saharsa-mineral environment of the mold fungus Aspergillus niger in-depth method.After separation of the coarse fraction of mycelium titratable acidity of the solution was 15.2%.In the fermented solution was added 2 g/DM3pre-prepared activated suspension containing bentonite 10 wt.% and incubated the mixture for 40 minutes, after which the precipitate is separated and the solution having a titratable acidity of 14.6%, passed through a layer of non-woven fabric of a carbon sorbent brand Carbon-asset, having a volume of sorption pores of 0.35 cm3/g, taken in an amount of 4.8 g per 1 DM3solution. After passing determine the performance of the pure solution: titratable acidity, color by measuring the optical density of the solution at a wavelength of equal to 364 nm, the protein content by the method of Lowry, the surface tension of the solution by the method of separation of the ring. The obtained data are presented in the table.Example 2
Conduct the fermentation medium on the basis of hydrolyzed starch and cleaning fermented solution analogously to example 1. As a carbon sorbent use woven material brand Busofit-TM, iatesta obtained acid solution presented in the table.Example 3
Conduct the fermentation medium and cleaning fermented solution analogously to example 1. As a carbon sorbent use woven material brand OUT-M, having a volume of sorption long 0,50 cm3/g and taken in an amount of 3.0 g per 1 DM3solution.Indicators of quality of purified acid solution presented in the table.Example 4
Conduct the fermentation medium and cleaning fermented solution analogously to example 1. As a carbon sorbent use woven material brand Carbon-asset, having a volume of sorption long 0,80 cm3/g and taken in an amount of 2.0 g per 1 DM3solution.Indicators of quality of purified acid solution presented in the table.Examples 5 to 8
Conduct the fermentation medium and cleaning fermented solution analogously to example 1, use grade a carbon fiber material sorbent, respectively as in examples 1 to 4, and the acid solution is treated by immersing in it a carbon sorbent, which after exposure is separated by filtration.Indicators of quality of purified citric acid solution presented in the table.
3solution. After filtration define the indicators of quality of purified citric acid solution.Thus, the proposed method obtained the purified citric acid solution, in which, in comparison with the prototype, remains the same content acid, reduced the color of the solution and the content of proteins, in addition, judging by the increased surface tension of the pure solution to 65,0 - 65,3 10-3H/m, reduced the content of surface-active substances, for example, amino acids, enzymes and others.Cleaned the proposed method of solution of citric acid can be used to obtain the known ways of concentrated citric acid of commercial quality.Sources of information
1. Instruction manual for the production of citric acid. - L.: KNEIPP, 1981. - 130 C.2. The application for the invention of the Russian Federation N 96114341/13, IPC 6 C 12 P 7/48, Method of production of citric acid. 1. The method of obtaining citric acid, including the fermentation of carbohydrate-containing raw materials, purification of fermented rasteniya the solution process of a carbon sorbent, having a volume of sorption time limit 0,30 - 0,80 cm3/g, taken in an amount of 2.0 to 12.0 g per 1 DM3solution.2. The method according to p. 1, characterized in that a carbon sorbent used activated carbon fiber material selected from the group including brand material OUT-M, Busofit-T Busofit-TM, Carbon asset.
FIELD: biotechnology, microbiology, organic chemistry.
SUBSTANCE: invention relates to a method for preparing organic acids, in particular, citric acid. Method involves isolation of calcium citrate and acid stable amylolytic enzymes from the solution cultural fluid after fermentation with fungus Aspergillus niger. The isolation process is carried out at temperature 10-50°C and pH 3.2-5.9. Method provides increasing yield of calcium citrate and complex of acid stable amylolytic enzymes: α-amylase and glucoamylase.
EFFECT: improved preparing method.
1 tbl, 6 ex
FIELD: microbiological industry, in particular production of citric acid and acid-resistant α-amylase and glucoamylase enzymes.
SUBSTANCE: claimed method includes starch and maize flour hydrolysis in ratio of 1:7-1:40 with bacterial α-amylase enzyme preparation at elevated temperature and pressure to obtain value of carbon source dextrose equivalent not more than 30; addition of nitrogen organic source and mineral salts such as copper (II), zinc, cobalt (II) sulfates in amount of (0.5-1.0)x10-3, (1.5-3.5)x10-3, (1.5-4.5)x10-3 g/dm3, respectively, iron (II) to starch and maize flour hydrolyzate followed by medium fermentation with acid-forming fungi Aspergillus niger. Than hydrolyzate is diluted with sterile water to obtain fermentable sugar content of 120-140 g/dm3 and carbon and nitrogen organic source in ratio of (50-60):1, respectively. Method of present invention males in possible to convert sugar to citric acid with yield of 79.3-83.1 % and to obtain acid-resistant α-amylase and glucoamylase enzymes having activities of 2.50-3.50 U A-C/cm3 and 80.2-147.4 U Gl-C/cm3, respectively.
EFFECT: method for production of citric acid, α-amylase and glucoamylase with increased yield.
1 tbl, 4 ex
FIELD: microbiological industry, biochemistry.
SUBSTANCE: invention relates to a method for preparing citric acid and a complex of acid-stable amylolytic enzymes possessing activity of α-amylase and glucoamylase. Method involves separation of mycelium of fungus Aspergillus niger as a producer of acid from a fermented solution with the protein concentration 1.5-7.0 g/dm3 at temperature ≤32°C. Prepared fermented solution is purified by successive filtration processes through membranes with pores diameter values 0.65, 0.45 and 0.15 mcm and separated by ultrafiltration through a membrane retaining substances with molecular mass in limits 1000-50000 Da and providing preparing citric acid solution and acid-stable amylolytic enzymes solution. Citric acid solution with the protein content 0.05-0.15 g/dm3 is cleared preliminary followed by its concentrating, crystallizing and citric acid crystals are separated from mother liquor. Mother liquor with optical density value 0.1-0.4 at λmax = 400 nm is recovered to the concentrating step and solution with optical density 0.41-0.8 at λmax = 400 nm is cleared preliminary and recovered to the concentrating step. Solution of above mentioned enzymes is dried by sublimation or spraying up to preparing a dry complex with enzymatic activity of α-amylase and glucoamylase 700-900 and 10000-15000 U/g, respectively, or solution is precipitated followed by drying up to preparing the dry complex with enzymatic activity of α-amylase and glucoamylase 1000-1300 and 20000-26000 U/g, respectively. Method provides simultaneous preparing crystalline citric acid and a dry complex of acid-stable amylolytic enzymes with the high quality and high yield.
EFFECT: improved preparing method.
2 tbl, 5 ex
FIELD: microbiological industry.
SUBSTANCE: citric acid is obtained by fermentation of fungi Aspergillus niger. Fermentation is carried out in periodic mode in at least three fermenters wherein one of these fermenters is the head one, to produce in head fermenter organic acid concentration of 110-140 g/dm3 and sugar concentration of 3-5 g/dm3. and in the rest fermenters 80-90 g/dm3 and 10-12 g/dm3, respectively. Fermentation id continuous mode is carried out in two step in fermenter battery connected in parallel with the head on, wherein organic acid and sugar concentrations are maintained at 12-16 g/dm3, and viscosity is maintained at 0.04-0.05 Pa.s. In this purpose cultural liquid with sugar concentration of 3-5 g/dm3 is periodically evacuated from head fermenter and cultural liquid with sugar concentration of 10-12 g/dm3 is evacuated from the rest ones, and nutrient solution and sterile water are added thereto.. Additionally carbohydrate sources and mineral salts are introduced.
EFFECT: increased citric acid yield due to increased fermenter productivity.
2 cl, 1 tbl, 3 ex
SUBSTANCE: method provides the hydrolysis of starch-containing raw materials, following adding of the mineral salts to the obtained hydrolysate and medium fermentation with acid-forming fungi Aspergillus niger. The hydrolysis is carried out with ferment preparate of bacterial α-amilase at increased temperature and excessive pressure. The starch-containing raw material are rice flour allowed beforehand in the water at 20-25°C during 10-12 hrs. in amount of 205.3-235.7 g and rye flour in amount of 232.0-290.6 g. The carbon and nitrogen ratio in the obtained rice flour suspension is provided respectively equal (20.0-23.0):1, in rye flour suspension - (14.0-16.0):1. The ferment preparate is added up to achieving of carbon source dextrose equivalent value 35-40%. The sugars conversion to citric acid is 86.7-93.2%. α-amilase and glucoamylase activity is respectively 4.5-6.2 units A,C/cm3 and 160-180 units Gl.C/cm3.
EFFECT: increase of α-amilase and glucoamylase yield while maintaining the high yield of citric acid.
1 tbl, 7 ex
FIELD: food industry.
SUBSTANCE: citric acid production method involves preparation of Aspergillus niger VKPM F-696 producer fungus strain conidia. For spawn growing one prepares a nutrient medium based on sand sugar in the presence of a water-soluble complex of C60 fullerene with polyvinylchloride in an amount of 0.75-1.25 mg per 1 cm3 of the nutrient medium, C60 fullerene content being 0.5-0.7%. Spawn is grown. The nutrient medium based on sand sugar is prepared for fermentation and inoculated with the spawn with subsequent fermentation. Citric acid yield is 97.1 - 98.4%.
EFFECT: citric acid yield increase.
1 tbl, 3 ex
FIELD: food industry.
SUBSTANCE: method envisages the fermenter cleaning, nutritional medium loading into the fermenter and subsequent sterilisation of the nutritional medium and the fermenter with an antiseptic agent under overpressure equal to 0.08-0.10 MPa during 10-30 minutes at a temperature of 20-25°C.
EFFECT: sterilisation time reduction combined with preservation of absolute sterility of nutritional media.
2 tbl, 5 ex
SUBSTANCE: invention relates to biotechnology. The strain of fungus Aspergillus niger B-6 is the producer of citric acid. The strain Aspergillus niger is deposited in the joint Russian Collection of Agrocultural Microorganisms RAAS (RCAM) under registration number RCAM02149 and can be applied in the production of citric acid.
EFFECT: invention makes it possible to increase the output of citric acid.
2 tbl, 6 ex