Important Synthetic Flavor Compounds - Part 4 (ethyl 3 methyl butyrate ethyl hexanoate isopropyl acetate isobutyl acetate isoamyl acetate isoamyl butyrate ethyl acrylate or ethyl cis-4 octanoate ethyl trans-2, cis-4-decadienoate allyl hexanoate)

ethyl 3 methyl butyrate ethyl hexanoate isopropyl acetate isobutyl acetate isoamyl acetate isoamyl butyrate ethyl acrylate or ethyl 2-propenoate ethyl cis-4 octanoate ethyl trans-2, cis-4-decadienoate allyl hexanoate

Editor

09 Mar 2026 • 14 min read

Important synthetic flavor compounds: ethyl 3 methyl butyrate ethyl hexanoate isopropyl acetate isobutyl acetate isoamyl acetate isoamyl butyrate ethyl acrylate or ethyl cis-4 octanoate ethyl trans-2, cis-4-decadienoate allyl hexanoate.

These are among the 128 synthetic flavor compounds that John Wright, in his book Flavor Creation, suggests every flavorist should know and work with.

Part 4 (ethyl 3 methyl butyrate, ethyl hexanoate, isopropyl acetate, isobutyl acetate, isoamyl acetate, isoamyl butyrate, ethyl acrylate, or ethyl 2-propenoate, ethyl cis-4 octanoate, ethyl trans-2, cis-4-decadienoate, allyl hexanoate)

Here's the revised content with CAS numbers, standardized formatting, regulatory clarity, safety details, and expanded technical information for each compound:

Important Synthetic Flavor Compounds - Part 4 (Enhanced Edition)

Ethyl 3-Methyl Butyrate (Ethyl Isovalerate)

CAS Number: 108-64-5
FEMA Number: 2463
Regulatory Status: FEMA GRAS
Flavor Note(s): Powerful and substantive fruity note, similar to a more powerful version of ethyl butyrate, backed by a less obvious note of pineapple. Has a very distinct profile from its structural isomer ethyl 2-methyl butyrate.
Odor Threshold: Approximately 1–5 ppb in water (very potent)
Compounds That Render Similar Flavor Note: Ethyl butyrate (fruity, pineapple), though ethyl 3-methyl butyrate is more powerful and substantive.
Compounds Often Used Together With: A great partner for a number of related esters, especially ethyl butyrate, ethyl 2-methyl butyrate, and ethyl hexanoate.
All Potential Applications: Extremely versatile. Used in tropical fruits (cherimoya, jackfruit, kiwi, lychee, mango, passionfruit, pineapple), berry fruits (blackberry, blackcurrant, blueberry, cherry, cranberry, raspberry, strawberry), and other fruits (apple, apricot, Concord grape, lemon/lime, orange, watermelon).
General Usage Levels: Dose rates suggested for flavors intended to be dosed at 0.05% in ready-to-drink beverages or simple bouillon (ppm in flavor concentrate):
- Blueberry: 8,000–10,000 ppm
- Jackfruit: up to 3,000 ppm
- Pineapple: up to 3,000 ppm
- Passionfruit: ~2,000 ppm
- Apple: ~1,000 ppm
- Strawberry: ~1,000 ppm
- Watermelon: ~1,000 ppm
- Blackberry: ~800 ppm
- Mango: ~500 ppm
- Cranberry: ~500 ppm
- Raspberry: ~500 ppm
- Apricot: ~300 ppm
- Cherry: ~200 ppm
- Orange: up to 200 ppm
- Concord grape: ~200 ppm
- Blackcurrant: ~100 ppm
- Kiwi: ~100 ppm
- Lemon/Lime: ~100 ppm
- Lychee: ~20 ppm
  In finished products: 0.1–50 ppm depending on application.
Safety & Handling: Colorless to pale yellow liquid. Flash point: 80°F (27°C). Found widely in nature. Store in a cool, dry place in tightly sealed containers, away from ignition sources. Flammable. Shelf life: 24 months.

Ethyl Hexanoate (Ethyl Caproate)

CAS Number: 123-66-0
FEMA Number: 2439
Regulatory Status: FEMA GRAS
Flavor Note(s): Sweet, fruity, pineapple, waxy, fatty and estry with a green banana nuance. The taste is sweet, pineapple, fruity, waxy and banana with a green, estry nuance.
Odor Threshold: Approximately 1–10 ppb in water
Compounds That Render Similar Flavor Note: Ethyl butyrate (pineapple, but lighter), isoamyl acetate (banana, but less fatty-waxy).
Compounds Often Used Together With: Often used with ethyl butyrate, ethyl 3-methyl butyrate, and other esters to build complex fruit profiles.
All Potential Applications: Pineapple, banana, strawberry, and other fruit flavors for beverages, candies, baked goods, and dairy products.
General Usage Levels: In finished products: 5–50 ppm (pineapple: 15–40 ppm; banana: 10–30 ppm; strawberry: 5–20 ppm). In flavor concentrates: 0.05–0.5% (500–5000 ppm).
Safety & Handling: Colorless to yellowish liquid. Flash point: 121°F (49°C). Slightly soluble in propylene glycol; insoluble in water and glycerin. Soluble in fixed oils and most organic solvents. Store in a cool, dry place in tightly sealed containers, away from ignition sources. Shelf life: 24 months.

Isopropyl Acetate

CAS Number: 108-21-4
FEMA Number: 2926
Regulatory Status: FEMA GRAS. Food Chemicals Codex listed.
Flavor Note(s): Ethereal, fruity, sweet, banana, with a slight chemical nuance. Also described as tutti frutti, fruity, apple, banana-like.
Odor Threshold: Approximately 10–50 ppb in water
Compounds That Render Similar Flavor Note: Ethyl acetate (ethereal, but less banana), isoamyl acetate (banana, but more pronounced and less chemical).
Compounds Often Used Together With: Used with other fruity esters and solvents to create top notes in fruit complexes.
All Potential Applications: Fruit flavors (banana, apple, tutti frutti) and as a solvent in flavor formulations. Naturally occurs in apple, banana, cheddar cheese, cocoa, grape, honey, melon, pineapple, and strawberry.
General Usage Levels: Recommended smelling at 10.00% in dipropylene glycol. In finished products: 5–30 ppm. In flavor concentrates: 0.05–0.3% (500–3000 ppm).
Safety & Handling: Extremely flammable. Flash point: 62°F (17°C). Very volatile. Must be stored away from all ignition sources in a cool, well-ventilated area. Use explosion-proof equipment. Ground containers when transferring. Store in tightly sealed containers. Shelf life: 24 months.

Isobutyl Acetate

CAS Number: 110-19-0
FEMA Number: 2175
Regulatory Status: FEMA GRAS
Flavor Note(s): Sweet, fruity, etherial with an apple banana nuance. The taste is sweet, fruity with a banana tutti frutti note.
Odor Threshold: Approximately 10–50 ppb in water
Compounds That Render Similar Flavor Note: Isopropyl acetate (more chemical banana), isoamyl acetate (stronger banana), ethyl acetate (more ethereal).
Compounds Often Used Together With: Used with other acetate esters and fruity components in apple, banana, pear, and tutti frutti flavors.
All Potential Applications: Fruit flavors, particularly apple, banana, pear, and tutti frutti. Used in beverages, candies, baked goods, and as a solvent.
General Usage Levels: In finished products: 5–50 ppm. In flavor concentrates: 0.05–0.5% (500–5000 ppm). For banana: 15–40 ppm; for apple/pear: 10–30 ppm; for tutti frutti: 20–50 ppm.
Safety & Handling: Flammable. Flash point: 60°F (16°C). Very soluble in alcohol, fixed oils, and propylene glycol; slightly soluble in water. Store in tightly sealed containers away from heat and ignition sources. Use explosion-proof equipment. Shelf life: 24 months.

Isoamyl Acetate

CAS Number: 123-92-2
FEMA Number: 2055
Regulatory Status: FEMA GRAS. JECFA number 43. Listed in 21 CFR 172.515.
Flavor Note(s): Apple, banana, pear. It is the classic "banana" character with sweet, fruity, and pear-like undertones.
Odor Threshold: Approximately 10–50 ppb in water
Compounds That Render Similar Flavor Note: Isoamyl butyrate (softer, more fruity), amyl acetate, isopropyl acetate (chemical banana).
Compounds Often Used Together With: Used with ethyl acetate, ethyl butyrate, and other esters to build banana, pear, and tutti frutti profiles. Also used with isoamyl alcohol for depth.
All Potential Applications: Banana, pear, apple, tutti frutti, and other fruit flavors for candy, beverages, baked goods, chewing gum, and dairy products.
General Usage Levels: Used at moderate to high levels. In finished products: 10–100 ppm (can be higher in candy: 50–200 ppm). In flavor concentrates: 0.1–1.0% (1000–10,000 ppm).
Safety & Handling: Colorless liquid. Flash point: 77°F (25°C). Flammable. Store in a cool, dry place away from ignition sources. Soluble in alcohol and most organic solvents; slightly soluble in water. Shelf life: 24 months.

Isoamyl Butyrate

CAS Number: 106-27-4
FEMA Number: 2060
Regulatory Status: FEMA GRAS
Flavor Note(s): Strong, fruity, banana, pear, peach. The taste is sweet.
Odor Threshold: Approximately 10–50 ppb in water
Compounds That Render Similar Flavor Note: Isoamyl acetate (stronger, sharper banana), amyl butyrate, isoamyl isobutyrate.
Compounds Often Used Together With: Used with isoamyl acetate, ethyl butyrate, and other esters to build complex fruit profiles, especially for banana, pear, peach, and apricot.
All Potential Applications: Banana, pear, peach, apricot, and other fruit flavors for beverages, candies, baked goods, and dairy products.
General Usage Levels: In finished products: 5–50 ppm. In flavor concentrates: 0.05–0.5% (500–5000 ppm). For banana: 10–40 ppm; for pear/peach: 8–30 ppm; for apricot: 5–25 ppm.
Safety & Handling: Colorless to pale yellow liquid. Sum of isomers: >98%. Flash point: 136°F (58°C). Insoluble in water. Keep in tightly closed container in a cool and dry place, protected from light. When stored for more than 24 months, quality should be checked before use. Shelf life: 24 months.

Ethyl Acrylate (Ethyl 2-Propenoate)

CAS Number: 140-88-5
FEMA Number: 2418
Regulatory Status: FEMA GRAS but subject to strict usage limits. JECFA evaluation 2004 (Session 63). Due to its lachrymatory nature and safety profile, regulatory status may be restricted in some applications.
Flavor Note(s): Intense, harsh, fruity aroma. It is described as a lachrymator (tearing agent).
Odor Threshold: Approximately 1–5 ppb in water
Compounds That Render Similar Flavor Note: Ethyl methacrylate, methyl acrylate (harsh, fruity).
Compounds Often Used Together With: Limited use in flavors due to safety concerns; may be used with other esters in pineapple and other fruit notes at very low levels.
All Potential Applications: Pineapple and other fruit flavors, though use is highly restricted.
General Usage Levels: Extremely low levels due to potency and safety considerations. In finished products: typically 0.01–0.5 ppb if used. In flavor concentrates: 0.0001–0.0005% (1–5 ppm). Use only as a highly diluted solution.
Safety & Handling: Colorless mobile liquid. Lachrymator (tearing agent). Extremely flammable. Flash point: 50°F (10°C). Boiling point: 99–101°C. Soluble in ether and oils; slightly soluble in water. Requires extremely careful handling with adequate ventilation, fume hood, and full PPE (chemical-resistant gloves, safety goggles, face shield). Store away from all ignition sources. Polymerizes upon exposure to light and heat; stabilize with inhibitor. Due to safety profile, consider alternatives where possible. Shelf life: 12 months with inhibitor.

Ethyl cis-4-Octenoate

CAS Number: 34495-71-1
FEMA Number: 3344
Regulatory Status: FEMA GRAS
Flavor Note(s): A fruity pear-like note with slight citrus connotations.
Odor Threshold: Very low; approximately 0.1–1 ppb in water
Compounds That Render Similar Flavor Note: Ethyl trans-4-octenoate, ethyl 2-octenoate, other unsaturated C8 esters with pear-like character.
Compounds Often Used Together With: Used with ethyl hexanoate, ethyl decadienoate, and other unsaturated esters to build pear, apple, and tropical fruit profiles.
All Potential Applications: Pear, apple, and tropical fruit flavors where a fresh, fruity character is desired.
General Usage Levels: In finished products: 0.5–10 ppm. In flavor concentrates: 0.005–0.1% (50–1000 ppm). For pear: 2–8 ppm; for apple: 1–5 ppm; for tropical: 1–6 ppm.
Safety & Handling: Store tightly sealed under inert gas in a cool, well-ventilated area. Insoluble in water; soluble in alcohol. Emerging research suggests this substance may possess notable antimicrobial properties, particularly in combating prevalent foodborne microorganisms like Salmonella and Listeria. Shelf life: 24 months from manufacture date. Protect from light and air.

Ethyl trans-2, cis-4-Decadienoate

CAS Number: 3025-30-7
FEMA Number: 3148
Regulatory Status: FEMA GRAS (Publication No(s): 4, 25). JECFA Flavor Number 1192.
Flavor Note(s): Fruity, pear, apple, tropical. It is known for its powerful, sweet, and juicy pear-like character with fatty-green undertones.
Odor Threshold: Extremely low; approximately 0.01–0.1 ppb in water
Compounds That Render Similar Flavor Note: Ethyl 2,4-decadienoate isomers, methyl decadienoate, and other unsaturated esters with pear character.
Compounds Often Used Together With: Used with ethyl hexanoate, ethyl octanoate, and other esters to build complex pear, apple, and tropical fruit profiles.
All Potential Applications: Pear, apple, pineapple, and other tropical fruit flavors for beverages, candies, and baked goods.
General Usage Levels: Extremely potent. In finished products: 0.1–5 ppm. In flavor concentrates: 0.001–0.05% (10–500 ppm). For pear: 0.5–3 ppm; for apple: 0.3–2 ppm; for tropical: 0.5–4 ppm.
Safety & Handling: Colorless to pale yellow liquid. As an unsaturated ester, it is prone to oxidation and isomerization. Store under inert gas (nitrogen) in tightly sealed containers, protected from light and heat. Minimize headspace. Shelf life: 12–24 months when properly stored.

Allyl Hexanoate (Allyl Caproate)

CAS Number: 123-68-2
FEMA Number: 2032
Regulatory Status: FEMA GRAS. JECFA number 3. Listed in 21 CFR 172.515.
Flavor Note(s): Pineapple. It has a sweet, fruity, juicy pineapple character with a slightly ethereal top note.
Odor Threshold: Approximately 5–25 ppb in water
Compounds That Render Similar Flavor Note: Allyl cyclohexylpropionate (pineapple, but heavier), ethyl hexanoate (pineapple, but less intense), methyl hexanoate.
Compounds Often Used Together With: Used with ethyl butyrate, ethyl hexanoate, and other esters to build complex pineapple and tropical fruit profiles.
All Potential Applications: Pineapple flavors, tropical fruit blends, and other fruit applications where a distinctive pineapple note is desired. Used in beverages, candies, baked goods, and chewing gum.
General Usage Levels: In finished products: 5–50 ppm (pineapple: 10–40 ppm; tropical blends: 5–30 ppm). In flavor concentrates: 0.05–0.5% (500–5000 ppm).
Safety & Handling: Colorless to pale yellow liquid. Flash point: 151°F (66°C). As an allyl ester, may have different regulatory considerations compared to non-allyl esters. Store in tightly sealed containers away from light and heat. Soluble in alcohol and oils; insoluble in water. Shelf life: 24 months.

Below is the original version

For the short list of synthetic flavor compounds, provided here is information flavorists need to know including 1) their FEMA number, 2) flavor note(s), 3) compounds that render similar flavor note, 4) compounds that are often used togather with the compound, 5) applications, 6) usage levels, 7) other things flavorists need to know.