CN102816802A

CN102816802A - Method for producing potassium gluconate through fermentation of Aspergillus niger

Info

Publication number: CN102816802A
Application number: CN 201210314571
Authority: CN
Inventors: 李贵伶; 崔光水; 徐月美; 张伟
Original assignee: SHANDONG KAISON BIOCHEMICAL CO Ltd
Current assignee: SHANDONG KAISON BIOCHEMICAL CO Ltd
Priority date: 2012-08-30
Filing date: 2012-08-30
Publication date: 2012-12-12

Abstract

The invention discloses a method for producing potassium gluconate through fermentation of Aspergillus niger, which comprises the following steps: performing one-step jet on starch and starch-containing materials, and performing double-enzyme glucose preparation; using an Aspergillus niger P1205X21 strain which is resistant to high-concentration K<+> to ferment the glucose solution, and feeding an ion membrane KOH solution in the fermentation process to obtain a potassium gluconate solution; and by using a thermal crystallization process of multiple-effect continuous evaporation and crystallization, directly evaporating and crystallizing in a multiple-effect evaporation crystallizer to obtain the potassium gluconate finished product. The invention has the advantages that the raw materials are rich and accessible, the cost is low, the fermentation product is simplex, the product quality is high and easy to control, no waste water and waste gas are generated, no calcium gluconate mother liquor and calcium sulfate waste are generated, the environmental pollution is greatly reduced, the process route is short, evaporation, crystallization, drying and other procedures during calcium gluconate preparation are reduced, vapor is saved, the power consumption is reduced, and the production cost is greatly lowered.

Description

Fermentation of Aspergillus niger is produced the method for Potassium Gluconate

Technical field

The present invention relates to a kind of method of fermentative prodn Potassium Gluconate, specifically is the method that adopts aspergillus niger strain to utilize starch and starchy material to produce Potassium Gluconate through two enzyme sugarings, deep layer aerobic fermentation.

Background technology

Potassium Gluconate is as accessory substance, and acidity regulator, sequestrant, yeast food etc. are used for solid beverage, premixing powder of cake, sweet food premixed powder etc. more.Main as nutritious prod, dietary supplement, sequestering agent.Be the agent of a kind of effective benefit potassium, it can keep seepage force in the cell, regulates the human acid-base balance, has vital role to keeping Skelettmuskel tension force.Being effective benefit potassium agent of the various kaliopenias of human body, is the good food fortifier of potassium.Potassium Gluconate class drug type is more in the U.S..

The method of producing Potassium Gluconate at present mainly contains two kinds: a kind of is decalcification method; Promptly utilize the fermentation of Aspergillus niger glucose production to obtain calcium gluconate solution; Obtain crystalline dextrose acid calcium through filtration, evaporation, crystallization, spinning, drying and packaging; Molten brilliant back adds sulfuric acid and generates glucono-and calcium sulfate precipitation, and glucono-adding Pottasium Hydroxide that obtains or salt of wormwood reaction are obtained the glucono-potassium solution, obtains the Potassium Gluconate product through evaporation, crystallization spinning, oven dry again; The 2nd, the heterogeneous catalytic oxidation method, the reaction that this genealogy of law gas, liquid, solid three-phase carries out in reactor drum, it is to be raw material with the crystalline dextrose; Preparing certain density glucose solution, is catalyzer with multi-element metal/Pd/carbon catalyst, palladium/charcoal alloy Pd (Pt)/C, and air is an oxygenant; 30--under 70 ℃; Glucose oxidase is become glucono-, bubbling air in reactor solution, and continue to flow and add certain density Na0H solution and keep certain pH value.Reacted solution concentrates, obtains the glucono-sodium crystal after the spinning, crystallization, oven dry, packing through cooling, suction filtration, filtrate decompression.Take off sodium then and produce glucono-solution, add KOH and obtain the glucono-potassium solution, obtain the Potassium Gluconate product through evaporation, crystallization spinning, oven dry again.In above-mentioned two kinds of working methods, there is deficiency separately.

It is not enough that the first method decalcification method is produced Potassium Gluconate:

1. production cost is high: because calglucon solubleness, causes fermentation sugared concentration low (＜15%) just less than 4%, reacting final product calglucon fermented liquid concentration is lower than 15%, and production cost is high;

2. cause environmental pollution: produce adding sulfuric acid simultaneously and produce solid waste calcium sulfate, be difficult to handle polluting;

3. the technology circuit is long, investment is big, energy consumption is high: after extracting calglucon earlier, after dissolving the brilliant KOH of adding solution again and reacting, extract Potassium Gluconate, need twice evaporation, crystallization, spinning, oven dry to cause that investment is big, energy consumption is high, production cost is high;

4. produce the calglucon waste liquor.

Second method heterogeneous catalytic oxidation method shortcoming is:

1. catalyst system therefor is after recycling certain number of times, and catalytic efficiency (descends, and inversion rate of glucose is reduced; Reaction times prolongs even basic catalytically inactive; Catalyzer must be scrapped renewal, and the corresponding unit product catalyzer consumption that improved also makes the products production cost higher;

2. the technology circuit is long, and cost is high;

3. because metal catalyst has certain toxicity, its product can not be used for foodstuff production as foodstuff additive usually, and is dangerous; Therefore, the application of product receives certain restriction.

Summary of the invention

The technical problem that the present invention will solve provides the method that a kind of production cost is low, processing line is short out, fermentation of Aspergillus niger low in the pollution of the environment, application safety is produced Potassium Gluconate.

For solving the problems of the technologies described above, the present invention includes following steps:

A, starch and starchy material added water and size mixing after, add high temperature resistant AMS, through once spray liquefier, add compounded saccharifying enzyme again and carry out saccharification, the saccharification after-filtration is produced glucose solution;

B, utilize black mold P ₁₂₀₅X ₂₁The strain fermentation glucose solution, stream adds ionic membrane KOH solution in the fermenting process, and the glucono-that neutralization produces generates the glucono-potassium solution;

C, the Potassium Gluconate purified solution is obtained the Potassium Gluconate finished product.

In the described steps A; The ratio of starch and water is 1:1-2 (W/ V), and using sulfuric acid or using KOH to regulate pH value is 6.0-6.5, adds high-temperature by 8-20u/g dry starch amount; Injection temperature is controlled at 100-115 ℃; Use dilute sulphuric acid to regulate pH value and be 4.0-4.5, add compounded saccharifying enzyme by 80-180u/g dry starch two, the enzyme that goes out stops saccharification filtering albumen.

Described saccharification time is 50-60 hour, and wine inspection is qualified, and DE value is warming up to 80-85 ℃ more than 97%, is incubated 30-40 minute and goes out enzyme termination saccharification.

Among the described step B, utilize aspergillus niger strain through the slant strains acclimation shaking culture, the shaking table acclimation and screening obtains black mold P ₁₂₀₅X ₂₁Bacterial classification; After the amplification culture of wheat bran bacterial classification, make spore suspension again; Press wheat bran 300g/ m ³Inoculum size adopts the flame sealing method that aspergillus niger spore suspension-s is inserted in the first class seed pot and cultivates, and after first order seed is cultivated maturation, changes the secondary seed jar over to and cultivates; Secondary seed changes ferment tank over to after cultivating maturation, controlled temperature, pressure, ventilation during the fermentation, and to keep pH value through automatic adding ionic membrane KOH solution be 4.5-6.0, and when glucose concn 0.5-0.8%, fermentation ends.

Described first order seed is cultivated and is undertaken by following condition: adopt the flame sealing method that aspergillus niger spore suspension-s is poured in the jar, control tank pressure 0.08-0.12MP, jar warm 35-38 ℃, ventilation 0.1-0.2m ³/ m ³.min, mixing speed 100--115rpm, pH value nature, when pH value is 2.9-3.1, total acid content>=0.1g/100ml, plant age the 7-11h microscopy do not have assorted bacterium, commentaries on classics secondary seed jar when mycelia is healthy and strong.

Described secondary seed is cultivated and is undertaken by following condition: the amount of first class seed pot be the secondary seed jar amount 10%, keep secondary pressure tank 0.08-0.12MPa, jar warm 35-38 ℃, ventilation 0.1-0.2m ³/ m ³.min, mixing speed 100rpm, pH value be 2.9-3.1, when total acid content>=0.1g/100ml, plant age 5-8h microscopy do not have assorted bacterium, commentaries on classics fermentor tank when mycelia is healthy and strong.

Described ferment tank is undertaken by following condition: the amount of secondary seed jar be fermentor tank amount 10%, tank pressure 0.08-0.12MPa, jar the temperature 35-41 ℃ of ventilation 0.1-0.2m ³/ m ³.min, add 25-40% ionic membrane KOH solution through stream in first sugared concentration 25-32%, mixing speed 80-100rpm, the fermenting process; Be neutralized into the glucono-potassium solution with producing glucono-in the fermenting process; The control pH value is 4.5-6.0; Fermentation period 20-30h stops fermentation when surveying residual sugar 0.5-0.8%.

Described Potassium Gluconate purified solution is carried out according to the following steps: Potassium Gluconate soln using high-temperature condensation water is heated to 70-80 ℃, again through the Plate Filtration decon; Decolouring, filtration; Evaporative crystallization in the multiple-effect evaporation mold, controlled temperature 60-105 ℃, vacuum tightness-0.09--0.03 MPa; Separation, drying.

Advantageous effect of the present invention is: have abundant raw material and be easy to get, and raw materials cost all do not contain organic nutritive salt well below liquid sugar and crystalline dextrose in seed culture and the fermention medium, not only practice thrift cost but also be beneficial to extraction, the finished product foreign matter content is low; The just sugared concentration of fermentation is high, the cycle is short, controlled temperature is high (concentration can reach more than 30%, cycle 20-30h, 40 ℃ of temperature), fermenting process is easy to control, product is prone to extract, be easy to big suitability for industrialized production, and bacterial classification is at high density K ⁺Normally fermentation under the condition.It is low to have cost simultaneously, and tunning is single, and the quality product height is easy to control, advantages such as no waste water and gas generation; No glucono-mother liquor of calcium and calcium sulfate refuse produce, and significantly reduce environmental pollution; Processing line is short out, has reduced operations such as evaporation when producing calglucon, crystallization, oven dry, and energy consumption is low.With starch, starchiness (sucrose) be raw material through double-enzyme method sugar making, the deep layer aerobic fermentation, directly stream adds ionic membrane KOH solution during the fermentation; Obtain the glucono-potassium solution, avoided in the fermenting process stream to add lime carbonate, generate calglucon after; Adding sulfuric acid obtains adding Pottasium Hydroxide again behind the glucono-; After extracting, obtain glucose potassium, cause the production circuit long, cost is high.Adopt steam ejection liquefaction double-enzyme method sugar making technology than second spraying liquefaction; Can reduce steam consumption; Content was high when the protein in the liquid glucose was than second spraying simultaneously, and the proteic existence of part makes and no longer adds organic nitrogen source in the fermenting process in the liquid glucose, and is more favourable to subsequent extracted.In the purification of glucono-potassium solution, adopt the thermal crystalline technology of multiple-effect continuous evaporative crystallization, directly evaporative crystallization in the multiple-effect evaporation mold is practiced thrift steam, is reduced power consumption, and production cost reduces significantly.

Description of drawings

Fig. 1 is technological process of production figure of the present invention.

Embodiment

1. produce glucose solution:

1) size mixing:

In the ratio of starch and starchy material and water 1:1-2 (W/ V), starch is added in the jar of sizing mixing, use sulfuric acid or use KOH to transfer to pH value to be 6.0-6.5, add high-temperature by 8-20u/g dry starch; Stirred 20-30 minute.

2) steam ejection liquefaction:

Adopt one time steam ejection liquefaction technology, open starch pump slurries are controlled 5-50m ³/ h flow gets into injector: feed pressure is greater than vapor pressure 0.02-0.04Mpa, and temperature is controlled at 100-115 ℃, and adjusting slurry and steam are mixed into the pressure-bearing jar rapidly; Kept 5-6 minute; Get into flash tank, will expect temperature drop after 95--98 ℃, get into again and keep jar; Keep the inspection of 90-120 minute iodine qualified after, will expect that through interchanger temperature drop is to the 62--64 ℃ of entering PH jar of sizing mixing.

3) saccharification:

Use dilute sulphuric acid to transfer pH value to be 4.0-4.5, add saccharifying enzyme, squeeze into saccharifying tank by 80-180u/g dry starch, saccharification 50-55 hour, to survey DE value >=97%, and no longer obviously rise, the wine inspection is qualified, is warming up to 80-85 ℃, is incubated 30-40 minute and goes out enzyme termination saccharification.

4) filter:

With pump saccharification liquid is squeezed into plate-and-frame filter press, remove zein, obtain the liquid glucose of 15%--35%.

2. deep layer aerobic fermentation process:

Utilize aspergillus niger strain to cultivate through slant strains, shaking table screening domestication, screening obtains black mold P ₁₂₀₅X ₂₁Bacterial classification, through eggplant bottle amplification culture, the wheat bran culture of strains makes spore suspension.Press wheat bran 300g/ m ³Inoculum size adopts the flame sealing method that aspergillus niger spore suspension-s is inserted in the first class seed pot, carries out changing the secondary seed jar over to and cultivating after first order seed cultivates maturation.Secondary seed changes ferment tank over to after cultivating maturation, during the fermentation controlled temperature, pressure, ventilation and keep PH=4.5--6.0 through automatic adding ionic membrane KOH solution.Until glucose concn≤0.5% o'clock fermentation ends.Its process control procedure is:

The preparation of substratum:

1) dull and stereotyped, slant strains substratum: adopt Cha Shi-Duo Shi nutrient agar, its composition (w/v) is: sucrose 2%, SODIUMNITRATE 0.3%, Repone K 0.5% ₀, MAGNESIUM SULPHATE HEPTAHYDRATE 99.5 0.5% ₀, agar 2%, ferrous sulfate 0.01% ₀, agar 2%, water surplus, potassium hydrogenphosphate consumption on Cha Shi-Duo Shi nutrient agar basis by 1% ₀Be increased to 3% ₀, to improve the resisting high-concentration potassium ion of bacterial classification.

2) shaking table substratum g/L:

Glucose 150-250

NH ₄H ₂PO ₄ 0.4－0.8

K ₂HPO ₄ 0.04—0.06

KH ₂PO ₄ 0.2—0.4

MgSO ₄·7H ₂0 0.1—0.3。

3) wheat bran bacterium culture medium: composition is Testa Tritici and tap water, ratio 1:0.8-1.0.

4) first order seed substratum g/L:

Glucose 150-250

NH ₄H ₂PO ₄ 0.4－0.8

K ₂HPO ₄ 0.04—0.06

KH ₂PO ₄ 0.2—0.4

MgSO ₄·7H ₂0 0.1—0.3

The pH value nature.

5) secondary seed medium g/L:

Glucose 200-250

NH ₄H ₂PO ₄ 0.4－0.8

K ₂HPO ₄ 0.04—0.06

KH ₂PO ₄ 0.2—0.4

MgSO ₄·7H ₂0 0.1—0.3

The pH value nature.

6) fermention medium g/L:

Glucose 250-300

NH ₄H ₂PO ₄?0.4－0.8

K ₂HPO ₄?0.04—0.06

KH ₂PO ₄ 0.2—0.4

MgSO ₄·7H ₂0 0.1—0.3

PH value 4.5-6.0.

In slant strains substratum, wheat bran bacterium culture medium, a secondary seed medium, the fermention medium, do not add organonitrogen and other nutrition such as peptone, amino acid, steeping water, urea.Solved in other fermention mediums and to have added the cost waste problem that organonitrogen and other organic nutrient substance cause.And prevent the thalline overgrowing and output decline.Simultaneously, do not add above-mentioned nutrition, also be convenient to purify, further practice thrift cost.In dull and stereotyped, the slant strains substratum, the potassium hydrogenphosphate consumption on Cha Shi-Duo Shi nutrient agar basis by 1% ₀Be increased to 3% ₀, to improve the resisting high-concentration potassium ion of bacterial classification.Prevent in the fermenting process that stream adds K behind the KOH ⁺Concentration increases and causes somatic cells osmotic pressure rising influence to be fermented.

3. strain domestication screens and enlarged culturing:

Aspergillus niger strain is tamed, and the domestication purpose is to improve the resisting high-concentration potassium ion of bacterial classification, and the step of taming, screen, spread cultivation is following:

1) good used article and medium package, sterilized 7 minutes for 115 ℃.

2) a kind of rhyme scheme in Chinese operas serving as the prelude to a complete score for voices: under the aseptic technique, sterilization postcooling to 60-70 ℃ plate culture medium is poured in the petridish, evenly be paved with at the bottom of the plate, keep horizontal positioned, subsequent use after solidifying.

3) get aspergillus niger strain, process spore suspension, break up, be filled in the aseptic triangular flask in the pellet shot from a slingshot bottle.

4) draw bacteria suspension and in aseptic water pipe, do gradient dilution.

5) draw two of spore suspensions in petridish with aseptic straw, coating evenly.

6) culture temperature 36-37 ℃, be inverted and cultivated 3-4 days, treat that spore grows, move and be connected to slant medium.

7) inclined-plane is put in the 36-37 ℃ of constant incubator and was cultivated 6-7 days, and ripe back supplies the bacterial classification primary dcreening operation.

8) pack into triangular flask dress of the shaking table substratum branch for preparing, jumping a queue bandages 115 ℃ of sterilizations, and naturally cooling is subsequent use.

9) inoculation: aseptic condition is scraped and is got slant pore and insert the shaking in the bottle of shaking table substratum is housed, and send after gauze seals and shakes between bottle.

10) 36-37 ℃ of cultivation between shaking table, culturing process stream adds ionic membrane KOH, and control pH value 4.5-6.0 was cultivated 2-3 days.

11) choose: analyze each bacterial strain residual sugar, choose the low strain passage of residual sugar, 36-37 ℃, cultivated 6-7 days.

Make black mold P through above step repeated screening ₁₂₀₅X ₂₁Bacterial classification, this bacterial classification spreads cultivation through the inclined-plane, and carrying out wheat bran, to cultivate culturing step following:

1) batching: accurately take by weighing needed wheat bran amount according to consumption, according to wheat bran: water is 1:0.8-1.0, and poach installs the wrapping of jumping a queue by every 500ml triangular flask 30g wet feed.

2) sterilization: with the bottle that the bandages Autoclave of packing into, at 0.1Mpa, 20-30min sterilizes under 121 ℃ of conditions.

3) inoculation: scrape under the aseptic technique and get slant pore, be inoculated in the wheat bran substratum that makes and shake up 36-37 ℃ of cultivation.

4) inoculation is 6-7 days, all cover with spore inside and outside the substratum after, cultivate to finish, store between temporary.

5) before the first class seed pot inoculation, ripe wheat bran is broken up the back move in the cooled spore bottle of sterilization that is filled with water, it is subsequent use to process spore suspension.

4. a secondary seed spreads cultivation:

It is the wheat bran spore that baterial cultivation chamber is worth that one secondary seed spreads cultivation, and under the condition of the certain temperature of one, two seeding tank inner control, pressure, ventilation, cultivating becomes the mycelia seed with metabolic capacity.Its process control procedure is:

1) first order seed is cultivated:

Adopt the flame sealing method that aspergillus niger spore suspension-s is poured in the jar, control tank pressure 0.08-0.12MP, jar warm 35-38 ℃, ventilation 0.1-0.2m ³/ m ³.min, mixing speed 100--115rpm, pH value nature.When pH value is 2.9-3.1, always acid content >=0.1g/100ml, kind 7-11h microscopy in age do not have assorted bacterium, change the secondary seed jar when mycelia is healthy and strong.

2) secondary seed is cultivated:

The amount of first class seed pot be the secondary seed jar amount 10%, keep secondary pressure tank 0.08-0.12MPa, jar warm 35-38 ℃, ventilation 0.1-0.2m ³/ m ³.min, mixing speed 100rpm, pH value be 2.9-3.1, when total acid content>=0.1g/100ml, plant age 5-8h microscopy do not have assorted bacterium, commentaries on classics fermentor tank when mycelia is healthy and strong.

3) ferment tank:

The amount of secondary seed jar be fermentor tank amount 10%, tank pressure 0.08-0.12MPa, jar the temperature 35-41 ℃ of ventilation 0.1-0.2m ³/ m ³.min, in the first sugared concentration 25-32%, mixing speed 80-100rpm, fermenting process through auto-feeding 25-40% ionic membrane KOH solution, be neutralized into the glucono-potassium solution with producing glucono-in the fermenting process, the control pH value is 4.5-6.0.Fermentation period 20-30h stops fermentation when surveying residual sugar 0.5-0.8%.

5. the extraction of glucono-potassium solution:

1) filter:

Except that containing the main products Potassium Gluconate, also contain solid phase impurity such as mycelium, protein in the fermenting-ripening liquid, removing these solid phase impurity is the first steps that guarantee final product quality.Fermented liquid is heated to 70-80 ℃ with the process high-temperature condensation water, removes impurity such as thalline again through Plate Filtration.Make the fermented liquid clear, transparence>90%, filter the gained mycelium and take out to feed factory production protein fodder.

2) decolorization filtering:

Though the fermented liquid clear after the filtration, but still contain pigment, organism and colloidalmaterial, as not decolouring, the color and luster of fermented liquid can be deepened after evaporation, causes finished product to be tawny.This project adopts gac that fermented liquid is decoloured; 80 ℃ of insulation 30min decolouring heats up to add 3-5% gac (physics charcoal, chemical charcoal each 50%) in the fermented liquid; Decolouring finishes secondary fermentation liquid and removes gac through Plate Filtration; Be filtered to the clear liquid water white transparency, transparence>99%, get into the evaporative crystallization operation.

3) evaporative crystallization:

Sunmorl N 60S fermented liquid concentration behind decolorization filtering is lower, can not direct crystallization, must concentrate the concentration that improves Sunmorl N 60S in the fermented liquid.Conventional evaporative crystallization technique is intermittently evaporation, decrease temperature crystalline technology, and present method adopts the thermal crystalline technology of multiple-effect continuous evaporative crystallization, direct evaporative crystallization in the multiple-effect evaporation mold, controlled temperature 60-105 ℃, vacuum tightness-0.09--0.03 MPa.After a large amount of crystal occurring (crystalline content is more than 35%), control fermented liquid degree Beaume 45Be '--46 Be ' during mother liquor degree Beaume 46-47 Be ', turn down the discharging pump reverse flow valve, open bleeder valve.This method is than ordinary method energy-conservation 70%.

4) separate:

The material that the multiple-effect evaporation mold is emitted is the mixture of Sunmorl N 60S crystallization and mother liquor; Adopt the closed continuous centrifuge that the Sunmorl N 60S crystallization is separated with mother liquor, wash the impurity of plane of crystal in the sepn process with deionized water off, get rid of to 3-5% moisture when following with automatic centrifuge; Wet crystal directly gets into baking operation; Wash-down water and most mother liquor get into the evaporative crystallization operation again, and mother liquor reclaims and takes out to external process factory through after repeatedly handling.

This extraction process is different from the extraction process of the employed evaporation at intermittence of present domestic production enterprise, decrease temperature crystalline, tripodia spinning, and adopts novel production device, is evaporated to Crystallization Separation from mycelia separation, feed liquid; Adopted energy-conservation, automatic equipment; Realize serialization, robotization in the operation, both shortened the operational cycle, improved working efficiency; Reduce labour intensity, guaranteed quality product again.

5) dry, packing:

Sunmorl N 60S plane of crystal after the spinning is with a spot of free-water; Adopt novel HSVB series low frequency high amplitude vibrated fluidized bed that wet crystal is carried out drying; Dry good product is through cooling controlled temperature＜75 ℃, moisture＜0.5% o'clock, and the back gets into and weighs automatically, packaging facilities; And sampling detects warehousing after passing.

By 5 instances of the present invention that above step and condition are implemented, the practical implementation condition is following:

Claims

1. a fermentation of Aspergillus niger is produced the method for Potassium Gluconate, it is characterized in that may further comprise the steps:

2. fermentation of Aspergillus niger according to claim 1 is produced the method for Potassium Gluconate, it is characterized in that in the described steps A that the ratio of starch and water is 1:1-2 (W/ V); Using sulfuric acid or using KOH to regulate pH value is 6.0-6.5; Add high temperature resistant AMS by 8-20u/g dry starch amount, injection temperature is controlled at 100-115 ℃, uses dilute sulphuric acid to regulate pH value and is 4.0-4.5; Add compounded saccharifying enzyme by 80-180u/g dry starch amount, the enzyme that goes out stops saccharification filtering albumen.

3. fermentation of Aspergillus niger according to claim 2 is produced the method for Potassium Gluconate, it is characterized in that described saccharification time is 50-60 hour, and the wine inspection is qualified, and DE value is warming up to 80-85 ℃ more than 97%, is incubated 30-40 minute and goes out enzyme termination saccharification.

4. fermentation of Aspergillus niger according to claim 1 is produced the method for Potassium Gluconate, it is characterized in that among the described step B that utilize aspergillus niger strain through the slant strains acclimation shaking culture, the shaking table acclimation and screening obtains black mold P ₁₂₀₅X ₂₁Bacterial classification; After the amplification culture of wheat bran bacterial classification, make spore suspension again; Press wheat bran 300g/ m ³Inoculum size adopts the flame sealing method that aspergillus niger spore suspension-s is inserted in the first class seed pot and cultivates, and after first order seed is cultivated maturation, changes the secondary seed jar over to and cultivates; Secondary seed changes ferment tank over to after cultivating maturation, controlled temperature, pressure, ventilation during the fermentation, and to keep pH value through automatic adding ionic membrane KOH solution be 4.5-6.0, and when glucose concn 0.5-0.8%, fermentation ends.

5. fermentation of Aspergillus niger according to claim 4 is produced the method for Potassium Gluconate; It is characterized in that described first order seed is cultivated is undertaken by following condition: adopt the flame sealing method that aspergillus niger spore suspension-s is poured in the jar, control tank pressure 0.08-0.12MP, jar warm 35-38 ℃, ventilation 0.1-0.2m ³/ m ³.min, mixing speed 100--115rpm, pH value nature, when pH value is 2.9-3.1, total acid content>=0.1g/100ml, plant age the 7-11h microscopy do not have assorted bacterium, commentaries on classics secondary seed jar when mycelia is healthy and strong.

6. fermentation of Aspergillus niger according to claim 4 is produced the method for Potassium Gluconate; It is characterized in that described secondary seed is cultivated is undertaken by following condition: the amount of first class seed pot be the secondary seed jar amount 10%, keep secondary pressure tank 0.08-0.12MPa, jar warm 35-38 ℃, ventilation 0.1-0.2m ³/ m ³.min, mixing speed 100rpm, pH value be 2.9-3.1, when total acid content>=0.1g/100ml, plant age 5-8h microscopy do not have assorted bacterium, commentaries on classics fermentor tank when mycelia is healthy and strong.

7. fermentation of Aspergillus niger according to claim 4 is produced the method for Potassium Gluconate; It is characterized in that described ferment tank is undertaken by following condition: the amount of secondary seed jar be fermentor tank amount 10%, tank pressure 0.08-0.12MPa, jar the temperature 35-41 ℃ of ventilation 0.1-0.2m ³/ m ³.min, add 25-40% ionic membrane KOH solution through stream in first sugared concentration 25-32%, mixing speed 80-100rpm, the fermenting process; Be neutralized into the glucono-potassium solution with producing glucono-in the fermenting process; The control pH value is 4.5-6.0; Fermentation period 20-30h stops fermentation when surveying residual sugar 0.5-0.8%.

8. fermentation of Aspergillus niger according to claim 1 is produced the method for Potassium Gluconate; It is characterized in that described Potassium Gluconate purified solution carries out according to the following steps: Potassium Gluconate soln using high-temperature condensation water is heated to 70-80 ℃, again through the Plate Filtration decon; Decolouring, filtration; Evaporative crystallization in the multiple-effect evaporation mold, controlled temperature 60-105 ℃, vacuum tightness-0.09--0.03 MPa; Separation, drying.