乙酸酐

synonyms

  • acetic anhydride
  • Acetyl acetate
  • CAS 108-24-7
  • ICSC No. 0209
  • RTECS number AK1925000
  • (EC) No. 203-564-8
  • UN number 1715
  • Public Chemistry CID 7918

physical description

Acetic anhydride is a clear, colorless liquid with a strong vinegar smell. Flash point 129 °F. Corrodes metals and tissues. Density 9.0 lbs/gallon. Used in the manufacture of fibers, plastics, pharmaceuticals, dyes and explosives.
Acetic anhydride is an acyclic carboxylic acid anhydride derived from acetic acid. It functions as a metabolite and a reagent.
Acetic anhydride is a natural product found in grapes.

Acetic anhydride is a clear, colorless liquid with a strong vinegar smell. Flash point 129 °F. Corrodes metals and tissues. Density 9.0 lbs/gallon. Used in the manufacture of fibers, plastics, pharmaceuticals, dyes and explosives.

What is acetic anhydride?

Purpose

In the food industry, acetic anhydride is used as a starch modifier.

describe

It is a clear liquid with a pungent vinegar smell.

The chemical formula is (CH 3 CO) 2 O.

It was first discovered in 1852. Interestingly, the French chemist who produced it was Charles Frédéric Gerhardt. Gerhard died in 1856 at the age of 39. He was poisoned by chemicals while conducting experiments.

Acetic anhydride uses

Used in the production of aspirin, acetaminophen and other drugs. As a food additive, it is used in the production of modified starch. Modified starch improves stability to heat and mild acids. They are then used to thicken food. They are also used as stabilizers or emulsifiers.

Acetic anhydride is used to convert cellulose into cellulose acetate. Cellulose acetate is a component of photographic film. With digital photography now becoming mainstream, this may not be so common anymore.

By the way, it is also used to produce heroin from morphine.

Common foods containing acetic anhydride

Acetic anhydride is used in many products, but primarily in frozen foods, ice cream, frozen cakes, dry cake mixes, flavored toppings and sauces, mayonnaise, snacks, and granola bars.

E number:

The E value of acetic anhydride is 1420.

Safety and efficacy of feed additives consisting of acetic acid for all animal species

On February 1, 2012, the European Food Safety Authority's Panel on Additives and Products or Substances used in animal feed (FEEDAP) adopted an opinion on the safety and effectiveness of acetic acid as a feed preservative. The opinion follows the submission of an application under Article 10(2) of Regulation (EC) No 1831/2003 concerning the existing product acetic acid.

The FEEDAP panel has evaluated the safety of acetic acid in its previous opinion. In the opinion, the panel concluded that based on comparisons between consumer exposure to acetic acid and target animal exposures, as well as limited experimental data on chickens and dogs fed diets containing acetic acid or its salts, the maximum concentration is 2.5 g Acetic acid/kg of complete feed (or 1 g/liter of drinking water) is safe for poultry, pigs and pets. The known high endogenous acetate production in ruminants suggests a rather high level of tolerance in these target animals.

Given the extensive and rapid metabolism of acetic acid and its salts, their use in animal nutrition is not expected to result in substantial human exposure.

Acetic acid and its salts are bulk industrial chemicals and the dangers of handling these substances are well known and documented. The risks to personnel handling free acids and the risk phrases that appear on material safety data sheets and labels depend on the concentration. Therefore, in the EU, dilute acid (10-25%) is considered an irritant, while at higher concentrations it is corrosive and at concentrations above 90% it is flammable.

The FEEDAP team concluded that the use of acetic acid in animal production poses no risk to the environment.

The characteristics of this additive and the conditions of its use are the same as those already evaluated by the FEEDAP Panel in its previous comments on acetic acid. The expert panel concluded that the new manufacturing process would not affect the safety of target species, consumers, users and the environment.

The FEEDAP panel has evaluated the efficacy of acetic acid in its previous opinion. In this opinion, the expert panel expressed reservations about the effectiveness of acetic acid and its salts as preservatives in complete feeds with typical moisture contents of ≤12%. However, it is recognized that under actual storage conditions the moisture content of all or part of the feed may be higher than this level. In these cases, additives can be effective in preventing or reducing the extent of deterioration.

The properties and conditions of use of the additives are the same as those already evaluated in previous comments. The expert panel concluded that the efficacy of the product was not affected by the new manufacturing process and, therefore, the same conclusion applies to acetic acid produced by this manufacturing process.

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