Isoamyl acetate

Description

In commercial practice amyl invariably means isoamyl, unless it is prefaced by the n- for normal. Isoamyl acetate has a powerful, fruity odor with a bittersweet taste reminiscent of pear. If impure, the odor is strong, penetrating, and almost shocking. Usually prepared by esterification of commercial isoamyl alcohol with acetic acid.

Description

Isoamyl acetate is naturally produced by ripening fruit. It creates a strong, fruity banana or pear odor that is widely used to flavor foods, attract bees, and improve the smell of everything from perfumes to shoe polish. It is even used as a solvent for oil colors, lacquers, and resins; and, strangely enough, it can be used to test gas masks.

Chemical properties

Isoamyl Acetate is a strongly fruity-smelling liquid and has been identified in many fruit aromas. It is the main component of banana aroma and is, therefore, also used in banana flavors.
All isomers of amyl acetate are highly flammable, colorless to yellow, watery liquids.
Isoamyl acetate has a fruity, banana, sweet, fragrant, powerful odor with a bittersweet taste reminiscent of pear. If impure, the odor is strong, penetrating and almost shocking. In commercial practice, amyl invariably means isoamyl.

Physical properties

Clear, colorless liquid with a banana or pear-like odor. Odor threshold concentration is 7 ppm (quoted, Keith and Walters, 1992). A detection odor threshold concentration of 18 μg/m³ (3.4 ppbv) was determined by Katz and Talbert (1930).

Occurrence

Reported to be found in a number of naturally occurring products, including apple, banana, cocoa bean, coffee, cognac, grape, peach, pear, pineapple and strawberry

The Uses of Isoamyl acetate

Isoamyl acetate is used to impart pear flavorto mineral waters and syrups, in perfumes, inthe manufacture of artificial silk or leather, inphotographic films, in dyeing textiles, and asa solvent.

The Uses of Isoamyl acetate

Sting pheromone of the honeybee.1

The Uses of Isoamyl acetate

In alcohol solution as a pear flavor in mineral waters and syrups; as solvent for old oil colors, for tannins, nitrocellulose, lacquers, celluloid, and camphor; swelling bath sponges; covering unpleasant odors, perfuming shoe polish; manufacture of artificial silk, leather or pearls, photographic films, celluloid cements, waterproof varnishes, bronzing liquids, and metallic paints; dyeing and finishing textiles. A special grade of the amyl acetate has been used for burning in the Hefner lamp serving as a photometric standard.

The Uses of Isoamyl acetate

banana oil is a carrier oil. The banana family is of more interest for its nutritional value rather than for its botanical properties. The use of plantain juice as an antidote for snake bites has been reported in parts of Southeast Asia since 1916.

What are the applications of Application

Isopentyl acetate is a widely employed ester

Definition

ChEBI: The acetate ester of isoamylol.

Production Methods

The commerical-grade isoamyl acetate is prepared by the esterification of amyl alcohol (often fusel oil) with acetic acid and a small amount of sulfuric acid as the catalyst .

Preparation

By the esterification of commercial isoamyl alcohol with acetic acid

Taste threshold values

FEMA PADI: 24.491 mg

General Description

Oily liquid; colorless; banana odor. Floats and mixes with water. Flammable, irritating vapor is produced .

Air & Water Reactions

Highly flammable. Insoluble in water.

Reactivity Profile

Isoamyl acetate is an ester. Esters react with acids to liberate heat along with alcohols and acids. Strong oxidizing acids may cause a vigorous reaction that is sufficiently exothermic to ignite the reaction products. Heat is also generated by the interaction of esters with caustic solutions. Flammable hydrogen is generated by mixing esters with alkali metals and hydrides. Isoamyl acetate can react violently with oxidizing materials, nitrates, strong alkalis and strong acids.

Hazard

Flammable, moderate fire risk. Irritant. Explosive limits in air 1–7.5%.

Health Hazard

Isoamyl acetate exhibits low toxicity; thetoxic effects are comparable to those of n amyl acetate. The toxic symptoms includeirritation of the eyes, nose, and throat;fatigue; increased pulse rate; and narcosis.Inhalation of its vapors at 1000 ppm for30 minutes may cause irritation, fatigue, andrespiratory distress in humans. It is more narcotic than are the lower acetic esters. TheLD50 value in rabbits is on the order of7000 mg/kg.

Fire Hazard

FLAMMABLE. Flashback along vapor trail may occur. Vapor may explode if ignited in an enclosed area. When heated emits acrid fumes. When exposed to flames can react vigorously with reducing materials.

Flammability and Explosibility

Flammable

Potential Exposure

(n-isomer): Primary irritant (w/o allergic reaction), (sec-isomer) Human Data. Amyl acetates are used as industrial solvents and in the manufacturing and dry-cleaning industry; making artificial fruit-flavoring agents; cements, coated papers, lacquers; in medications as an inflammatory agent; pet repellents, insecticides and miticide. Many other uses.

Carcinogenicity

Not listed by ACGIH, California Proposition 65, IARC, NTP, or OSHA.

Source

Identified among 139 volatile compounds identified in cantaloupe (Cucumis melo var. reticulates cv. Sol Real) using an automated rapid headspace solid phase microextraction method (Beaulieu and Grimm, 2001).

Environmental Fate

Chemical/Physical. Slowly hydrolyzes in water forming 3-methyl-1-butanol and acetic acid.

Shipping

UN1993 Flammable liquids, n.o.s., Hazard Class: 3; Labels: 3-Flammable liquid, Technical Name Required.

Purification Methods

Dry the acetate with finely divided K2CO3 and fractionally distil it. [Beilstein 2 IV 157.]

Incompatibilities

Vapors may form explosive mixture with air. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides, nitrates. May soften certain plastics.

Waste Disposal

Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber. All federal, state, and local environmental regulations must be observed. In accordance with 40CFR165, follow recommendations for the disposal of pesticides and pesticide containers. Must be disposed properly by following package label directions or by contacting your local or federal environmental control agency, or by contacting your regional EPA office.