01
Introduction to sodium diacetate
Sodium diacetate, abbreviated as SDA, is a white crystalline powder with acetic acid smell. It is easy to absorb moisture and soluble in water and alcohol. Its crystal structure is regular hexahedron, melting point is 96 ~ 97 ℃, and it is decomposed when heated to more than 150 ℃. It is combustible and stable under cool and dry conditions. Sodium diacetate has antibacterial effect mainly by decomposing molecular acetic acid, and it has good inhibitory ability against bacteria and molds.
02
Technical index of sodium diacetate
GB 25538-2010 food additive sodium diacetate stipulates that the technical indexes of sodium diacetate are:
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03
Safety and advantages of sodium diacetate
Sodium diacetate is a molecular compound of sodium acetate and acetic acid. It is one of the food, feed and grain preservatives approved by the state. In 1941, it was first used in the mildew prevention of bread by the United States. In the 1970s, it was used in the mildew prevention and preservation of Cereals, corn and feed abroad, and achieved good results. In 1977, the food and Agriculture Organization of the United Nations and the World Health Organization (FAO / who) approved SDA as a food additive and published its quality standards. In 1982, the U.S. Food and Drug Administration (FDA) recognized SDA and passed the "gras" (unanimously recognized safety) qualification. In July 1990, the Ministry of health of China published the hygienic standards for the use of SDA in food.
Compared with similar traditional products, sodium diacetate has many advantages. The dosage of sodium diacetate is only 1 / 3 ~ 1 / 2 of propionic acid and its salt, and the price is 1 / 2; Its inhibitory effect on Xanthomonas is better than that of calcium propionate, potassium sorbate and sodium benzoate, and its antifungal effect on Rhizopus and Trichoderma is better than that of clearing mold and Aspergillus. Sodium diacetate is suitable for mildew prevention of newly harvested grain with high water content. It can effectively increase the nutritional value of feed, improve the appetite of pets, be harmless to humans and animals, and have no pollution to the environment. It has become the first choice of mildew inhibitor for grain and feed.
04
Preparation method of sodium diacetate
The preparation process of sodium diacetate includes two main processes: chemical synthesis reaction and crystal formation. The chemical synthesis reaction process is to neutralize or associate the reaction raw materials with acetic acid (or acetate) molecules at a certain temperature to obtain the molecular association complex of acetic acid and sodium acetate. The crystal formation process is to cool down in water or ethanol medium to make the molecular association complex form crystals.
According to the raw materials used, the preparation methods can be divided into acetic acid sodium acetate method, acetic anhydride sodium acetate method, acetic acid acetic anhydride sodium carbonate method, acetic acid sodium carbonate method, acetic acid sodium hydroxide method, etc. Among them, acetic acid sodium carbonate method and acetic acid sodium hydroxide method are the most suitable for industrial production.
05
Application of sodium diacetate
Sodium diacetate is commonly used as preservative in food, grain and feed, and has a wide range of uses in chemical industry.
1. Used as food preservative
Sodium diacetate has a good anti-corrosion effect and is widely used in the anti-corrosion of bread, beer, barley, meat products, cans and pickled vegetables.
2. Used as grain mildew inhibitor
Sodium diacetate is used as an anti mildew preservative for various grain products, including rice, wheat, corn, beans, flour, peanuts, etc. sodium diacetate has a prominent advantage, that is, it does not need to dry the newly harvested grain with a water content of more than 20%, which has a significant anti mildew effect. China is a large grain producing country. The traditional grain storage method is to dry it to less than 12% water content before it can be stored in the warehouse. Even so, a large amount of grain is still lost due to mildew every year. The use of sodium diacetate for grain mildew prevention has the advantages of no drying, simple operation, saving manpower, material resources and site, low cost, long shelf life, good mildew prevention effect and remarkable social and economic benefits.
3. Used as feed mildew inhibitor and additive
Sodium diacetate can effectively inhibit the growth of mold spores in feed and prevent feed mildew. It is suitable for the anti mildew agent of various silages, mixed feed and raw materials. The cost of using sodium diacetate as feed anti mildew agent is only about 2 / 3 of propionate, and the economic benefit is very good. As a feed additive, sodium diacetate can not only prevent mildew, but also increase the nutritional value and palatability of the feed. The special sour taste of sodium diacetate can mask the unpleasant smell and taste of other additives in the feed, significantly enhance the palatability of the feed and improve the utilization rate of nutrients in the feed. Animals prefer to eat the feed containing sodium diacetate, and the nutritional status has been significantly improved.
4. Other purposes
Sodium diacetate can be used as veterinary medicine to treat hemorrhagic enteritis and piglet dysentery of Turkey and other poultry. Sodium diacetate is one of the commonly used raw materials of food acidity. In the organic synthesis industry, it can be used to prepare coumarin by the reaction of salicylic acid and acetic anhydride. It can also be used as chemical buffer, electroplating additive, plant growth regulator and fuel color fixing agent.
06
Usage and dosage of sodium diacetate in pet food
The addition of sodium diacetate in pet food can reduce the water activity and denature the cell protein. By changing the cell morphology and structure, the cell can dehydrate and die, so as to play an anti mildew role.
When sodium diacetate is used in pet food, it can be processed into a solution and sprayed evenly on pet food, or it can be fully mixed with other trace additives and added to pet food. When sodium diacetate is added in the form of crushing, the anti mildew effect is better than that in the form of liquid addition, while the micro powder form is more effective, which is twice as effective as that in the form of liquid addition. If it is mixed with sodium benzoate, the effect is better. When the water content of pet food is the same, the more the added amount, the longer the safe storage time. When the water content increases, the added amount also increases, generally when the added amount is 0.1% ~ 0.5% 8%。
07
Precautions for storage of sodium diacetate
It should be stored in a cool and dry place, and the fumes can be decomposed and pungent. The shelf life is generally two years. In the process of feed processing, high temperature should be avoided to prevent the decomposition of sodium diacetate and reduce the use efficiency.
In addition, sodium diacetate packaging uses plastic bags as inner packaging and woven bags for outer packaging; During storage, the warehouse shall be clean and dry to prevent rain and moisture, and shall not be mixed with other alkaline substances, pesticides, chemicals and other toxic substances. During transportation, the means of transportation shall be kept clean to prevent pollution by pesticides, chemicals and other toxic and harmful substances.
Part source: Zhang Hongli, preservatives, fungicides and Acidity Regulators - Sodium Diacetate