Structural formula CH3CH=CHCH=CHCOOK
The scientific name is potassium hexadiene-(2,4)-acid. Colorless to white scaly crystals or crystalline powder, odorless or slightly smelly. Unstable in air. Can be oxidized and colored. Molecular weight 150.22. It is hygroscopic. Soluble in water and ethanol.
Production method: neutralization method is mainly adopted. It is made of sorbic acid by neutralization reaction with potassium carbonate or potassium hydroxide.
Use: cosmetic preservative. Belonging to organic acid preservatives. The addition amount is generally 0.5%. Can be mixed with sorbic acid. Although potassium sorbate is easily soluble in water and easy to use, its1%aqueous solution has a pH value of 7-8, which tends to increase the pH value of cosmetics, so attention should be paid to it when using it.
When we buy packaged (or canned) food, we often see the words "sorbic acid" or "potassium sorbate" in the ingredients, and people often mistake them for the ingredients of the fruit "pear". In fact, they are commonly used food additives! Whether they are harmful to the human body or not, it is really necessary to clearly consume them. The following information about sorbic acid and potassium sorbate is for reference only:
Sorbic acid (chemical name: 2,4-hexadienoic acid molecular formula: C6H8O2)
Potassium sorbate (chemical name: potassium 2,4-hexadienoate) molecular formula: C6H7KO2)
Sorbic acid and potassium sorbate have similar properties and uses;
Sorbic acid is an efficient and safe preservative recommended by FAO and WHO. It is widely used in food, beverage, tobacco, pesticide, cosmetics and other industries. As an unsaturated acid, it can also be used in resin, perfume and rubber industries.
The difference between potassium sorbate and sodium benzoate
Taking potassium carbonate as potassium sorbate, firstly, potassium carbonate has no antiseptic effect, and it can't have the proper bacteriostatic effect of potassium sorbate, because it is sorbate, not potassium ion, that has the bacteriostatic effect. This kind of fake and inferior products will harm the interests of dealers, users and consumers. Second, the product will change color, affecting sensory indicators. According to the regulations, the appearance of normal potassium sorbate is white. However, the potassium sorbate product mixed with potassium carbonate will change color from white to yellow or brown after being stored for about 3 months, which will affect the sales.
Taking potassium benzoate as potassium sorbate, although potassium benzoate has antiseptic effect, it also has certain toxic and side effects on human body, and potassium sorbate is recognized as a safe food additive in the world. In the process of food production, replacing potassium benzoate and sodium benzoate with potassium sorbate is conducive to improving food safety and conforming to the trend of healthy consumption.
Potassium sorbate mixed with potassium carbonate will turn yellow or brown after being stored for 3 months. Some unscrupulous enterprises add chemical brighteners to fake and inferior products to increase the whiteness of products and cover up the yellow color produced after deterioration. According to health experts, these chemical brighteners will cause serious harm to human health.
The fake potassium sorbate produced by some small enterprises is still white when it first leaves the workshop. Potassium sorbate with low quality and low price will change color and have poor anticorrosion effect. Potassium sorbate with extremely low price is definitely of poor quality.
According to insiders, the imperfect product standard is a fundamental reason why fake and inferior potassium sorbate flooded the market. The current national standard of potassium sorbate in China is formulated on the basis of referring to the FCC standard of the United States. In China's national standards and American FCC standards, the determination of the purity (content) of potassium sorbate is based on the "content of potassium ions".
Potassium sorbate is made from sorbic acid and potassium carbonate by chemical reaction, in which sorbate and potassium ions combine to form potassium sorbate. Because the prices of potassium carbonate and potassium benzoate are lower than sorbic acid, potassium carbonate is illegally added to the product.
Poor management is also a reason for the existence of fake and inferior potassium sorbate. At present, health supervision and quality supervision departments can supervise the quality of food additives.
Because potassium ion can't play an antiseptic role, and sorbate is the real bacteriostatic factor, so the current national standard of potassium sorbate should be revised and improved, and the criterion for determining the purity of potassium sorbate in the standard should be changed to "sorbate content" (originally potassium ion content). By modifying the standard in this way, the authenticity of products can be identified from the product terminal, and those products whose sorbate content is not up to standard can be judged as fake and inferior products, so that "products mixed with potassium carbonate or potassium benzoate" cannot enter the market.
Potassium sorbate is made of sorbic acid and potassium carbonate as raw materials. Because the production technology is simple, the key process can be completed in one step. Therefore, many owners of small enterprises can master this technology with a little learning, which is also an important reason for the increasing number of small potassium sorbate production enterprises. Due to the simple production facilities of many small enterprises, most of them only have a few houses, a reaction kettle, a blender, several manual sealing machines and other facilities, lacking purification devices and producing by hand, so their production costs are low, but the physical and chemical quality and sanitary quality of products are often unstable.
Anticorrosion
Sorbic acid (potassium) can effectively inhibit the activities of mold, yeast and aerobic bacteria, and also prevent the growth and reproduction of harmful microorganisms such as Botox, Staphylococcus and Salmonella, but it is almost ineffective for beneficial microorganisms such as anaerobic Bacillus and Lactobacillus acidophilus, and its inhibitory effect is stronger than sterilization, thus effectively prolonging the storage time of food and maintaining the original flavor of food. Its anti-corrosion effect is 5- 10 times that of the similar product sodium benzoate.
security
Because sorbic acid (potassium) is an unsaturated fatty acid (salt), it can be absorbed by the metabolic system of human body and quickly decomposed into carbon dioxide and water, and there is no residue in the body.
ADI 0-25mg/kg (calculated by sorbic acid, FAO/WHO 1994)
LD50 4920mg/kg (rat, oral)
GRAS （FDA， 182.3640 1994)
Its toxicity is only 1/2 of salt and 1/40 of sodium benzoate.
stability
Sorbic acid (potassium) is stable in a sealed state, easily absorbs water when exposed to humid air, and oxidizes to change color. Potassium sorbate has good thermal stability, and its decomposition temperature is as high as 270℃.
serviceable range
At present, it has been widely used in food, beverage, pickles, tobacco, medicine, cosmetics, agricultural products, feed and other industries. From the development trend, its application scope is still expanding.
Sorbic acid (potassium) is an acidic preservative, which still has a good antiseptic effect in foods close to neutral (PH6.0-6.5), while benzoic acid (sodium) has an antiseptic effect at pH >: At 4 o'clock, the effect has obviously decreased, and it has a bad taste.
usage mode
When in use, it can be directly added, sprayed, dipped, sprayed with dry powder, and treated on packaging materials.
What is the difference between sorbic acid and potassium sorbate?
Sorbic acid includes sorbic acid, potassium sorbate and calcium sorbate. Sorbic acid is insoluble in water, so it must be dissolved in ethanol or potassium bisulfate before use, which is inconvenient and irritating when used, so it is generally not used; Calcium sorbate is not often used because of its small scope of use as stipulated by FAO/WHO. Potassium sorbate does not have their shortcomings. It is soluble in water and widely used. We can often see it in some drinks, preserved fruits, canned foods and so on. Here I focus on potassium sorbate: it is unsaturated hexacarbonic acid; Potassium sorbate sold in the general market is white or light yellow particles, with a content of 98%-102%; It is odorless or slightly odorous, easy to absorb moisture, easy to oxidize and turn brown, stable to light and heat, with a relative density of 1.363 and a melting point of decomposition at 270℃. The pH of its 1% solution is 7-8. Potassium sorbate is an acidic preservative, which has high antibacterial performance and inhibits the growth and reproduction of mold. It mainly inhibits the growth of microorganisms and plays an antiseptic role by inhibiting the dehydrogenase system in microorganisms, and has inhibitory effects on bacteria, molds and yeasts; Its effect weakens with the increase of PH, and its bacteriostatic ability reaches the peak when PH reaches 3, and it still has bacteriostatic ability when PH reaches 6, but the minimum concentration (MIC) cannot be lower than 0.2%. Experiments show that the shelf life of food soaked in potassium sorbate solution with PH：3.2 is 2-4 times shorter than that without sterilization.
Sorbic acid, potassium sorbate and calcium sorbate have the same mechanism of action, and their toxicity is less than that of benzoic acid and nipagin ester. The daily allowance is 25mg/Kg, 5 times of benzoic acid and 2.5 times of nipagin ester, which is a relatively safe food preservative. In China, it can be used in soy sauce, vinegar, flour paste, jam, pickles, canned food and some wines.
Potassium sorbate CASNo.: 590-00-1sorbate CASNo.:110-44-1
HS No：29 16 190090
Although the state stipulates that sodium benzoate cannot be used for children's food and beverage, only sorbic acid or potassium sorbate can be used. However, due to the weak awareness of food safety in China at present, some manufacturers use toxic sodium benzoate in order to save costs, hoping to pay attention to the ingredients contained in various foods and drinks for the health of themselves and their families, and not to be careless. This toxicity will not cause us to die immediately or cause serious diseases immediately, but it is a hidden danger to our bodies and brings us great possibility of contracting various diseases such as cancer.