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Dehydroacetic Acid CAS 520-45-6

Molecular Formula: C8H8O4

Formula Weight: 168.15

ZSpharmac: Dehydroacetic Acid Supplier

Product Name: Dehydroacetic Acid
CAS No: 520-45-6
Purity: 99%

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Basic Info

Product Name:Dehydroacetic Acid
Other Names:Dehydroacetic Acid, 98%
Place of Origin:Shandong, China
Brand Name:ZSpharmac
Type:Cosmetic Raw Materials
Appearance:Light Yellow or Cream Fine Crystalline Powder
EINECS No.:208-293-9
Provide:Dehydroacetic Acid MSDS;
Dehydroacetic Acid COA

What is Dehydroacetic Acid?

Dehydroacetic acid is also known as 3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione, methyl acetylpyrone, DHA. Those precipitated from water are white acicular crystals or crystalline powders, and those precipitated from ethanol are prismatic crystals. odorless. Has a weak sour taste. The melting point is 109-110°C. The boiling point is 269.9%, 132~133°C (0.667×103Pa). Solubility (25°C, g/100g): acetone 22, benzene 8, methanol 5, ether 5, ethanol 3, carbon tetrachloride 3, propylene glycol 1.7, olive oil 1.6, n-hexane 0.7, water <0.1, glycerin <0.1, Also soluble in caustic solution. Non-hygroscopic. The pH of a saturated aqueous solution is 4. Dehydroacetic acid is an organic synthesis intermediate, a toughening agent, and a broad-spectrum food preservative. It has a strong antibacterial ability against mold and yeast, which is 2 to 10 times that of sodium benzoate. It is often used in the form of sodium salt in Preserve in fruit juice, fermented bean curd, pickles, and cakes. However, excessive use is harmful to humans and animals. Many countries have strict regulations on the use of this preservative. The maximum residue limit stipulated by the United States is 65mg/kg, and Japan and my country Taiwan allow it to be used in food. The limit is 0.5g/kg. my country’s food additive use standard GB2760-2014 stipulates that the limit of dehydroacetic acid in pickled vegetables and starch products is 1.0g/kg. In other products such as butter, pastries, meat products, juices, and seasonings It is stipulated that the added amount shall not exceed 0.3-0.5g/kg. Therefore, the accurate determination of dehydroacetic acid in food is a very important task to ensure food safety.

Dehydroacetic Acid Property

Melting point 111-113 °C (lit.)
Boiling point 270 °C (lit.)
density 1.1816 (rough estimate)
vapor pressure 0.001 hPa (20 °C)
refractive index 1.4611 (estimate)
Fp 157°C
storage temp. Store below +30°C.
solubility 2g/l
form Fine Crystalline Powder
color Light yellow or cream
PH4 (2g/l, H2O, 20℃)
Water Solubility 500mg/L at 25℃


Dehydroacetic Acid Uses

Dehydroacetic acid is used as an intermediate in organic synthesis; pastes of resin solutions such as vinyl acetate solutions and acrylic plastic emulsions, as well as pastes of combinations such as polyvinyl alcohol, carboxymethyl cellulose, starch, bone glue, etc; just recently extra commonly Utilized in adhesives, mosquito coils, feed, hair shampoo, tooth paste and various other areas; because this product has an inhibitory result on mold, yeast, and also Gram, it is utilized as an antifungal representative and also chemical in medicine, cosmetics, and food. GB2760-1996 specifies that it can be made use of in fermented bean curd, assorted pickles, as well as original orange juice, with a maximum use of 0.30 g/kg, and additionally used in cheese 0.01%~ 0.05%, butter as well as margarine 0.05%. Japan states that the maximum dosage is 0.5 g/kg; this product can be used as a low-toxicity stabilizer for PVC, especially when made use of in conjunction with Ca-Zn stabilizers, the effect is much better, it can boost transparency as well as protect against coloring; this product can be utilized with lots of Metals form control compounds and also can be utilized for shade evaluation; it is likewise used as a tooth decays preventative agent; cosmetic emulsifiable oil antifungal representative. As a result of poor water solubility, its sodium salt is normally used (see this short article). Rat oral LD501000mg/kg.

The Production Method of Dehydroacetic Acid

Method 1. Use cod liver or minced fish as raw material
Preparation of crude fish oil Take the fresh cod liver that has been removed from the gallbladder, washed and chopped, put it in a pot, add water, pass steam to 80°C, flow out the oil, filter, cool the filtrate to 0°C, precipitate solid fat, and filter under pressure , the filtrate is crude fish oil.
Fish oil [water]→[80°C] oil quality [filter]→crude fish oil or minced fish as raw material, minced, mixed with starch at 7-10°C, extracted with hexane for 15 minutes, filtered to obtain filtrate. The filtrate was washed with sodium chloride solution, then dehydrated with anhydrous sodium sulfate, and the hexane was recovered to obtain crude fish oil.
Minced fish [starch, hexane] → [7-10°C, 15min] filtrate [NaCl] → [anhydrous sodium sulfate] crude fish oil
Preparation of refined fish oil Take crude fish oil, add sodium hydroxide ethanol solution to saponify, filter, add acid to the filtrate, add water-insoluble organic solvent to extract, wash the extract with water, remove the organic layer, the water layer is light red or reddish brown The clear liquid was placed at 10°C for 30 minutes without solid precipitation to obtain refined fish oil.
Crude fish oil [alkaline ethanol solution] → filtrate [organic solvent] → [HCl] extract [washed] → refined fish oil
Pre-concentration and alcoholysis ethyl esterification of refined fish oil, use urea inclusion crystallization method to remove less saturated fatty acid in fish oil to obtain fatty acid ethyl ester of fish oil.
Refined fish oil [ethanol, urea inclusion crystal] → fish oil fatty acid ethyl ester
Preparation of DHA Put the fish oil fatty acid ethyl ester into the extraction tank, open the steel cylinder, after the CO2 is condensed, pressurize it to the set pressure by the high-pressure metering pump, and then preheat it to the working temperature, then enter the extraction tank. SC-CO2 carries fish oil fatty acid ethyl ester into the rectification column, and the components come out from the top of the column according to their solubility, and enter the separator for reception after decompression. Experimental conditions: extraction pressure is 11-15MPa, extraction temperature is 35°C; rectification pressure is 11-15MPa, rectification temperature is 40-85°C. Collect the EPA-rich fraction at 12-13.5MPa and the DHA-rich fraction at 14-15MPa, and measure with gas chromatography, EPA and DHA are purified to 90%. The EPA-rich fraction and the DHA-rich fraction are subjected to secondary extraction at 11.5-13MPa and 13.5-15MPa respectively, and the EPA is purified to 67%, and the DHA is purified to more than 90%.
Fish oil fatty acid ethyl ester [supercritical CO2 extraction] → [separation] DHA

Method 2: Use herring scraps as raw materials
Extraction of fish oil Mince herring scraps, add half the amount of water, adjust the pH to 8.5-9.0, keep warm for 45 minutes, add 5% salt, stir to dissolve, continue to keep warm for 15 minutes, filter, squeeze the filter residue, combine the filtrate and squeezed liquid , centrifuged while hot to make herring oil. The total content of EPA and DHA in herring oil is 8.9%.
Herring leftovers [H2O, 5%NaCl]→[pH8.5-9][filtered, centrifuged]→herring oil
Preparation of Polyunsaturated Fatty Acid (PUFA) Take herring oil, add sodium hydroxide ethanol (95%) solution, fill with nitrogen and reflux for saponification, cool the saponified solution to 15-20°C, a large amount of sodium salt of fatty acid is precipitated, squeeze and filter, and cool the filtrate To -20 ℃, and then press filter. Add an equal volume of water to the filtrate, adjust the pH to 3-4, and centrifuge for 10 minutes to obtain PUFA-I. Dissolve PUFA-I in sodium hydroxide ethanol solution, cool at -20°C, press filter, add a small amount of water to the filtrate, cool at -10°C, and remove cholesterol crystals by suction filtration. Add a small amount of water to the filtrate, cool at -20°C, centrifuge for 5 minutes, pour off the upper layer, and centrifuge for 10 minutes after the lower jelly (PUFA sodium salt) is acidified to obtain PUFA-II. The total content of EPA and DHA in PUFA-II is 64.8%.
Herring oil [NaOH ethanol] → [nitrogen] saponified liquid [cooling] filtrate [pH3-4] → [centrifugation] PUFA-I [NaOH ethanol] → PUFA-II

Method 3: Using arachidonic acid as raw material
Arachidonic acid is used as raw material to obtain EPA through desaturation. EPA grows through the C2 chain to obtain docosapentaenoic acid. Docosapentaenoic acid is desaturated to obtain DHA.
Arachidonic acid [desaturation] → EPAEPA
[C2 chain growth] → docosapentaenoic acid [desaturation] → DHA

Method 4. Supercritical multi-component fluid precision distillation technology
At present, the high vacuum distillation method, molecular distillation method, silver nitrate complex method, simple supercritical CO2 extraction and industrial chromatography preparation technology commonly used at home and abroad have many disadvantages and shortcomings, and are not suitable for high-purity EPA and DHA. Industrialization development. Using supercritical multi-fluid precision distillation technology to directly separate high-purity EPA and DHA, it is operated under normal temperature conditions, and the products are not easy to be oxidized and degraded. chemical production.

Method 5. Extraction of fish oil by light alkali hydrolysis
This process is to use light lye to decompose cod liver protein tissue and destroy the binding relationship between protein and liver oil, so as to more fully separate fish oil. This method of liver oil has good quality and low price, and most fish oil factories in my country use this method to produce fish oil.

Method 6. Potassium method to extract fish oil
The light alkali used in the traditional light alkali hydrolysis method to extract fish oil is a dilute solution of sodium hydroxide, and the salt is a sodium chloride solution. The process is very mature. However, the waste liquid generated during the extraction process has a high content of sodium salts and cannot be further utilized, forming new waste. According to the extraction principle of the light alkali hydrolysis process, Yang Guan’e et al. replaced sodium hydroxide and sodium chloride in the light alkali hydrolysis process with potassium hydroxide and potassium nitrate, and the extraction rate and quality of fish oil remained stable; the waste residue and waste liquid after extracting fish oil It contains a lot of amino acids and proteins, which can be further used as raw materials for high-efficiency green fertilizers, and no new waste is produced.
The extraction method is as follows: After homogenizing a certain amount of cod liver with a homogenizer, add it to a three-necked flask, add half to one and a half times the amount of water, stir in a water bath and heat up to 45-50°C, and add 40% potassium hydroxide twice Adjust the pH of the aqueous solution to 8-9, continue to stir and raise the temperature to 80-90°C, keep it warm for 30 minutes, add potassium nitrate with 4% weight of cod liver, continue to stir, salt out for 15 minutes, centrifuge while it is hot, and separate the crude fish oil.
Cod liver [water]→[45-50℃][4%KOH]→[pH8-9][80-90℃]→[30min][4%KNO3]→[15min][centrifugation]→crude fish oil
Product determination method: peroxide value-sodium thiosulfate back titration method; acid value-alkali titration method; iodine value-sodium thiosulfate titration method; saponification value-hydrochloric acid back titration method; DHA, EPA content determination-gas chromatography .
Results (n=3): The extraction rate of fish oil was 24.4%; the acid value was 2.58; the iodine value was 309; the saponification value was 178.7; the peroxide value was 0.070%; the DHA content was 19.60%.

Detection Method of Dehydroacetic Acid

The evaluation of dehydroacetic acid mostly includes two fundamental procedures of example pretreatment and also discovery. The matrix of food is reasonably intricate, and the example needs to be pre-treated to get rid of disturbance as well as enrich the components to be evaluated prior to resolution, so as to enhance the discovery sensitivity of the example and minimize the discovery restriction.

1) Ultra High Performance Liquid Chromatography (UPLC): With the help of the concept and also principle of HPLC (High Performance Liquid Chromatography), UPLC covers new innovations such as tiny fragment packing, really low system quantity as well as rapid discovery approaches, as well as raises the evaluation capacity. Throughput, level of sensitivity and also peak capability. Compared to typical HPLC, the speed, level of sensitivity as well as resolution of UPLC are 9.0, 3.0 as well as 1.7 times higher than that of HPLC, which reduces the evaluation time, reduces the quantity of solvent and decreases the evaluation expense. At present, UPLC technique is generally used in the fields of medicine, food, atmosphere, biochemical evaluation and more. Wang Feng developed an approach for the resolution of dehydroacetic acid in numerous foods by ultra-high performance fluid chromatography (UPLC). Techniques A CAPCELLPAKMG-C18 column was used, methanol-0.02 mol/L ammonium acetate (pH7.0-8.5)=10 ∶ 90 was utilized as the mobile phase, the circulation rate was 0.5 mL/min, the column temperature was 30 ° C, as well as the discovery wavelength was 293nm. The recuperation price was 97.6%-101.2%, the minimum detection limitation was 1 μg/ mL, as well as the relative standard deviation of the accuracy of the method was less than 10%.

2) High performance capillary electrophoresis (HPCE): HPCE is just one of the most quickly created logical methods in recent years. It is a sort of liquid phase splitting up innovation that is driven by a high-voltage electric area as well as uses a capillary as a separation channel to achieve splitting up according to the differences in mobility and distribution actions in between parts in the example. This method combines the usual advantages of chromatography and also electrophoresis technology, has a variety of different splitting up systems, and can meet the demands of intricate matrix food analysis to a big extent, and is increasingly more extensively utilized in the field of food as well as drug analysis. Zhang Lichun et al established high performance capillary electrophoresis (HPCE) for the simultaneous resolution of benzoic acid, sorbic acid, dehydroacetic acid and methyl p-hydroxybenzoate, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate as well as butyl p-hydroxybenzoate in beverages. ester method. Under the ideal problems of 40mmol/L borax salt barrier system, splitting up voltage of 25kV, pH9.35, detection wavelength of 200nm, as well as column temperature of 20 ° C, the 7 chemicals can be completely divided within 14 mins.

3) Gas chromatography-mass spectrometry (GC-MS): GC separates the mix right into solitary parts and then gets in MS for discovery and also evaluation, which can rapidly and also conveniently realize the splitting up and detection of multiple parts of intricate compounds. Lei Ningsheng et al. made use of GC-MS to spot dehydroacetic acid in fresh wet rice noodles. The sample was focused by dichloromethane vortex, ultrasonic removal and also high-speed centrifugation. The concentrated solution was separated by DB-5MS capillary column as well as ionized by EI source. The approach was spotted by GC-MS, the discovery restriction of the approach was 10 μg/ kg, the recovery price was 87.6%-113.0%, as well as the relative standard deviation was 3.54%-6.15%. Flavor Shuangshuang figured out dehydroacetic acid in meat products by GC-MS, and also separated and gauged 3 kinds of antioxidants and also 7 kinds of chemicals at the same time. 89.6% to 97.8%.

4) Fluid chromatography-mass spectrometry (LC-MS): 11 type of preservatives and also 6 type of anti-oxidants in spices were all at once identified by ultra-high efficiency fluid chromatography-tandem mass spectrometry (UPLC-MS/MS). After pretreatment, the extract was separated by a C18 reversed-phase column (150mm × 2.1 mm, 1.7 μm), 20mmol/L ammonium acetate liquid solution-acetonitrile was used as the mobile phase, gradient elution was done, and also unfavorable ion numerous response tracking (MRM) was utilized for electrospray ionization. mode for MS/MS discovery. Source temperature level: 120 ° C; capillary voltage: 3.1 kV; photomultiplier voltage: 650V; desolvation temperature level: 350 ° C; desolvation gas (nitrogen) circulation: 600L/h; collision gas (argon) circulation: 350L/h; Cone gas flow: 50L/h; retention time of dehydroacetic acid is 6.65 min, mass spectrometer criteria are parent ion 167m/z, product ion 83m/z (quantitative ion) as well as 123m/z, detection limit is 5mg/kg, The recoveries were between 94% and 118%, and the RSD worths were within 7%. Chen Xiaohong et al. also utilized ultrafast fluid chromatography-tandem mass spectrometry (UFLC-MS/MS) to at the same time measure dehydroacetic acid in rice a glass of wine and also wine and also attained great results.

About Products:
If you need Dehydroacetic Acid as a cosmetic raw material, please contact our service staff directly, and we will provide you with high-quality products at the best price.
As an experienced Dehydroacetic Acid manufacturer and supplier, ZSpharmac will provide Dehydroacetic Acid raw materials to customers all over the world for a long time.
Over the years, the company has been adhering to the spirit of “integrity management, strict quality control, customer first”, and has won unanimous praise from domestic and foreign customers.

Company Profile and Corporate Culture

Company Profile:

ZhiShang Chemical is owned by ZhiShang Group is a professional new-type chemicals enterprise combined into research and development, production and sales .

The company’s competitive product is pharmaceutical raw materials and intermediates (especially carbohydrate derivatives Series), In recent years, the company has made a major breakthrough in food and feed additives, plant extraction, industrial chemicals industry .

The company insists on the spirit of “sincere management, strict quality control, customer as god” , get consistent high praise from customers at home and abroad.

Corporate Culture:

Help China Chemicals to benefit the happiness of human life
Become the most trusted chemical supplier in the world
Striver – oriented, enrich employees, customer first, deep service, seek development
Be prepared for danger in times of peace, forge ahead actively, unity and cooperation, and be brave to fight

About Us

The production base is located in Zhangqiu chemical industry park and Tai’an high-tech chemical industry park. laboratory and workshop in strict accordance with the GMP standard and the product fit national ISO9001 and ISO2000 standards.

“Zhishang” products are exported to Europe, North and South America, the Middle East, Asia Pacific and Africa area, so as to establish a long-term and stable cooperation relationship with customer in the world.

Company Info
  • Business Type: Manufacturer
  • Product Range: Cosmetic raw materials
  • Products/Service:Cosmetic raw materials (flavors and fragrances,antioxidant products, moisturizing and hydrating, whitening agents, cosmetic additives)
  • Total Employees: 51~100
  • Capital (Million US $): 10000000RMB
  • Year Established: 2016
Production Capacity
  • No. of Production Lines : 8
  • No. of QC Staff : 5 -10 People
  • OEM Services Provided : yes
  • Factory Size (Sq.meters) : 3,000-5,000 square meters
  • Certificate: ISO9001 , CE , GMP , API , MSDS
  • Factory Location : Diao Town Industry Park, Zhangqiu City, Jinan City, Shandong Province, China.


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We will make samples before mass production, and after sample approved, we’ll begin mass production. Doing 100% inspection during production, then do random inspection before packing.



You can get free samples for some products,you only need to pay the shipping cost or arrange a courier to us and take the samples. You can send us your product specifications and requests,we will manufacture the products according to your requests.

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Our MOQ is 1kg. But usually we accept less quantity such as 100g on the condition that sample charge is 100% paid.

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Yes. We’ll give you product analysis report before shipping.

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Different quantity has different discount.


1. ≤50kg, Express delivery recommended, usually called as DDU service;

2. ≤500kg, Air shipping recommended, usually called as FOB, CFR, or CIF service;

3. >500kg, sea shipping recommended, usually called as FOB, CFR, or CIF service;

4. For high value products, please select air shipping and express delivery for safe.

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