What are Flavors Made of?

pic_lab1Flavor development labs usually have a lab bench, a scale and little bottles full of aromatics.These aromatics are natural extracts from plant materials and isolated aroma chemicals(synthetic or natural). All materials that are used to make food flavors MUST be approved to use in food at the level they are selected. A trade organization, Flavor Extract Manufacturers Association (FEMA) works with governing agencies to assure the safety of flavors. Often one flavor material can have several names. An easy way to keep track of components is to use the FEMA number (approval number). The most recent FEMA GRAS list is up to FEMA 4778 .

Some of the little bottles contain the various categories of materials :

Natural Extracts:

1)  Essential oils:  Aromatic oils obtained from the distillation or expression of plant materials.  For example: orange oil expressed (squeezed) from orange peel and peppermint oil steam distilled from mint leaves.

***** “fixed oils” such as nut oil are not essential oils because they are not aromatic****

2) Rectified Oils:  A further distilled essential oil that was processed to remove unwanted top notes or improve color.

3)  Folded oils:  Essential oils which are concentrated by distillation. Typically,terpenes(which have little flavor) are removed.  Because terpenes are removed, these essential oils are usually stronger in flavor and more soluble.

4)  Oleoresins:  Most often these are hexane extracted spices. Oleoresins usually contain the essential oil portion of the spice and the “taste” (non-volatile) component of the spice.  Examples are Ginger oleoresin, Cinnamon oleoresin and Black Pepper oleoresin.

4) Alcoholic extracts: An ethyl alcohol extract of a natural material.  For example: vanilla and chocolate extract. These extracts also often contain water, glycerine, corn syrup or propylene glycol.

Isolated Aroma Chemicals:

These chemicals are composed of the atoms: Carbon, Hydrogen, Oxygen, Nitrogen and Sulfur.  They are considered aromatic because they have a low hydrogen to carbon ratio, are fragrant and usually have a molecular weight less than 300.

1) Carboxylic acids: Organic acids characterized by the presence of at least one carboxyl group. The general formula of a carboxylic acid is R-COOH. Acids can be sour, like acetic acid (gives vinegar it’s sour taste) or can have a rancid flavor.

2) Alcohols: Chemical compounds having the general formula ROH, where R represents an alkyl group and –OH a hydroxyl group. An example of an alcohol for flavor use is cis-3-Hexenol which is green and fresh.

3)  Esters:  Organic compounds formed when an acid and an alcohol combine and release water. They have the general formula RCOORˈ, where R and Rˈ are organic radicals. Esters are typically colorless and have pleasant fruity or floral aroma.

4) Aldehydes & Ketones: Compounds that contain the carbonyl group c=o, a double bond between a carbon and oxygen atom. A ketone has two alkyl or aryly groups bonded to the carbonyl, because an aldehyde has one alkyl group and one hydrogen bonded to the carbonyl. These aromatics are very potent and add strong character to flavor; such as Benzaldehyde (smells strongly of almond or cherry).

5)  Lactones:  Organic compounds containing a ring of atoms in which the group –CO.O– forms part of the ring. These aroma chemicals are known to be woody, creamy and sweet.

6) Sulfides:  Organic compounds containing a sulfur atom. Usually they have a “ripe” or rotten odor.

7) Phenols: Chemical compounds having the general formula ROH, where R represents an aryl group and –OH a hydroxyl group.

8) Ethers: Chemical compounds having the general formula ROR.

9) Pyrazines: A group of organic compounds having a six-member ring in which the first and fourth atoms are nitrogen and the rest are carbon.  Often these compounds have strong roasted or nutty notes.

10) Mercaptans (also know as Thiols): A sulfur-containing organic compound with the general formula RSH.  These compounds are sometimes described as skunky. A well-known mercaptan is Furfuryl mercaptan which is reminiscent of coffee.

Useful references for learning about Flavor Materials include:

Fenaroli’s Handbook of Flavor Ingredients

Guenther: The Essential Oils 

Arctander’s Perfume and Flavor Materials of Natural Origin

Source Book of Flavors

Flavor scientist does not believe food flavors are safe for e-cig application, for more background, please see the statement from FEMA.

If you are interested in formulating flavors for food use, please see Flavor Knowledge System web page and class listings.