Enhancement of Marketability

Eating is not an automatic, boring routine that people go through in order to stay alive. Indeed, for most people, meals are pleasurable experiences in which diners savor the color, flavor, odor, texture, and other properties of the foods they eat. Corporations that prepare foods for sale have always been aware of this fact, and they have developed hundreds of food additives that enhance the attractiveness of food to consumers. The food additives used to increase the marketability of foods usually do little or nothing to make food safer, more healthful, or more long-lasting. They just make it more enjoyable to consume.

Some of the earliest food additives people used were naturally occurring substances that enhance the color, odor, or flavor of food. Historians know of dozens of natural substances used over the cen­turies to enhance the physical appeal of foods. The list includes rose petals to provide a reddish color to food, indigo stone for blue tints, saffron to add yellow, spinach juice to produce a greenish tint, violet flowers to give a purple color, and finely ground gold or silver to provide a metallic tint.

It was not until the latter 19th century, however, that chemists began to synthesize products that could be used as artificial food ad­ditives for the enhancement of color, odor, and flavor. The first such breakthrough was the discovery by Sir William Perkin (1838-1907) in 1868 of the structure of coumarin, a benzene derivative with the pleasant odor of new-mown hay. Perkin began to market coumarin as the first synthetic perfume, marking the beginning of the arti­ficial perfume industry. In addition to its pleasant odor, coumarin has a flavor very similar to that of vanilla, and for many years it was popular as the first synthetic food flavoring, replacing the far more expensive natural vanilla bean. Coumarin retained its popularity until the mid-1920s, when its toxic effects on the liver and kidneys were discovered. By that time, however, a research team consist­ing of the German chemist Ferdinand Tiemann (1848-99) and the French chemist Wilhelm Haarmann (1847-1931) had discovered the chemical structure of vanillin, the compound that gives vanilla its odor and taste. They began to manufacture vanillin as an artificial substitute for the natural product.

One major breakthrough in the early history of flavor chemistry was the discovery of the properties of the alkyl esters of organic acids, that is, compounds formed when an alcohol (such as methyl alcohol) reacts with an organic acid (such as butyric acid). This class of compounds has flavors and odors remarkably similar to a number of natural products. The first of these esters, methyl anthranilate, is said to have been discovered accidentally by German chemists searching for new perfumes. The ester filled the room with an over­whelming smell of grapes, making the product ideal as a flavor addi­tive for foods. The ester is still the component primarily responsible for the flavor of grape Kool-Aid.

Today, flavor chemists have developed an extensive list of alkyl esters that can be used as artificial flavors. Some of these compounds actually occur in the plants that they smell like, while others do not. The chart on page 40 lists some of the synthetic flavors most com­monly used today.

In spite of the pronounced odors of the alkyl esters, the most popular food additives used for flavoring are aldehydes. They are, in order of the amount used in foods annually: ethyl vanillin and vanillin (3-methoxy-4-hydroxybenzaldehyde; vanilla flavor), cinnamaldehyde (cinnamon flavor), and benzaldehyde (cherry flavor).

Today, the FDA authorizes the use of nine synthetic compounds and 21 naturally occurring substances for use as color additives in foods. These substances are listed in the chart on pages 41-42.

The FDA has also certified about 150 naturally occurring substances and more than 800 synthetic chemicals for use as flavor additives. The chart on page 43 lists a few examples of each of the approved groups.

Clearly, many additives are available to impart specific flavors and appealing colors to foods. In addition to these, food processors now add a number of other substances, some natural and others, mostly synthetic substances, to enhance other physical properties, extend shelf life, and make foods easier for consumers to work with. Some examples of those additives are the following: acidu-lants and alkalies, bleaching agents, emulsifiers, firming agents, humectants, leavening agents, stabilizers, surface active agents, and thickeners.

Acidulants and alkalies are added to foods to increase or decrease their acidity or "tartness." Examples of products used to increase acidity and tartness are acetic acid, citric acid, lactic acids, sorbic acid, and tartaric acid. Compounds used to decrease or counteract

< SOME ALKYL ESTERS WITH DISTINCTIVE FLAVORS >
NAME OF ESTER	FLAVOR
methyl butyrate	apple
ethyl butyrate	pineapple
amyl acetate	banana
isoamyl acetate	pear
amyl butyrate	apricot
octyl acetate	orange
ethylmethylphenyl glycidate	strawberry
ethyl anthranilate	Concord grape
isobutyl formate	raspberry
ethyl formate	rum
methyl salicylate	wintergreen
methylphenyl acetate	jasmine

acidity include sodium carbonate, calcium carbonate, and ammo­nium bicarbonate.

Anticaking agents are designed, as their name suggests, to prevent foods from clumping together. One of the most important appli­cations of anticaking agents is in the salt industry, where sodium

< PERMITTED NATURAL AND SYNTHETIC FOOD COLORING AGENTS V NATURAL COLORING AGENTS SYNTHETIC COLORING AGENTS* annatto extract FD&C Blue No. 1 beta-apo-8'-carotenal FD&C Blue No. 2 beta-carotene FD&C Green No. 3 beet powder FD&C Red No. 3 canthaxanthin FD&C Red No. 40 caramel color FD&C Yellow No. 5 carrot oil FD&C Yellow No. 6 cochineal extract Orange B cottonseed flour Citrus Red No. 2 ferrous gluconate fruit juice methylphenyl acetate grape color extract grape skin extract paprika

(continues)

< PERMITTED NATURAL AND SYNTHETIC FOOD COLORING AGENTS (continued) V
NATURAL COLORING AGENTS	SYNTHETIC COLORING AGENTS*
paprika oleoresin
riboflavin
saffron
titanium dioxide
turmeric
turmeric oleoresin
vegetable juice
*Colors approved according to the Food, Drug, and Cosmetics Act are referred to by designations known as FD&C color numbers.

silicoaluminate is widely used to prevent salt from caking together during transportation and storage. Other popular anticaking agents include calcium silicate and iron ammonium citrate.

Bleaching agents, such as chlorine, chlorine dioxide, and benzoyl peroxide, are used to increase the whiteness of a food product. They are used extensively to bleach flour and other wheat products.

Emulsifiers are used to form suspensions of watery foods with oily foods, such as the oil and vinegar that make up a salad dressing. They are widely used in the baking industry to control the size and texture of breads, cakes, and other products; to improve softness; to increase the volume of products; and to increase shelf life. Some

< SOME EXAMPLES OF APPROVED FLAVOR ADDITIVES V
NATURAL SUBSTANCES	SYNTHETIC SUBSTANCES
aloe	benzyl butyrate
blackberry bark	cinnamyl propionate
buchu leaves	cyclohexyl isovalerate
castor oil	diethyl sebacate
cubeb	ethyl pyruvate
hyacyinth flowers	geranyl formate
mimosa flowers	isoamyl nonanoate
orris root	methyl cinnamate
quebracho bark	phenethyl anthranilate
rhubarb root	sorbitan monostearate
spruce needles	undecyl alcohol
Source: Adapted from Code of Federal Regulations, Title 21, Chapter I, Part 172. Available online. URL: lula.law.cornell.edu/cfr/cfr.php?title=21&type=part& value=172.

common emulsifying agents are the polysorbates, sorbitan mono-stearate, glyceryl monostearate, and the acetic, lactic, citric, and fatty acid esters of glycerol.

Firming agents are substances that, as their name suggests, help foods to maintain a crisp or firm structure. They are often used as additives with fruits and vegetables that tend to grow soft after they have been harvested. They are also added to products like jams and jellies that are expected to retain a firm shape and not become watery or soupy. The most common firming agents are salts of cal­cium, such as calcium bisulfite, calcium citrate, calcium phosphate, calcium sulfate, and calcium gluconate.

Humectants are substances added to foods to promote the re­tention of moisture. These additives have the ability to form weak chemical bonds with water, keeping a product from drying out or becoming powdery. Some widely used humectants are propylene glycol, sorbitol, mannitol, glycerine, xylitol, propylene glycol, and polydextrose.

Leavening agents are substances that undergo a chemical reaction that produces carbon dioxide gas. As the gas forms and is warmed, it forms tiny bubbles that cause a product to "rise" and become fluffy. At one time, yeast was the most popular leavening agent used, but its action is not always dependable; it varies based on the age of the yeast culture, the temperature, the food to which it is added, and other factors. Today, the most popular leavening agents are salts of weak acids that hydrolyze (react with water) to produce hydrogen ions. They include sodium bicarbonate (baking soda), sodium alu­minum sulfate, calcium biphosphate, aluminum sulfate, and alumi­num phosphate.

Stabilizers are added to foods to hold them together and help them maintain a distinctive physical form. In many cases, a stabilizer plays the role of an emulsifier, maintaining a uniform dispersion of two immiscible (unmixable) substances. Some compounds used commercially as stabilizers are calcium carbonate, bicarbonate, and acetate; sodium and potassium citrate; sodium tartrate; and tannins.

Surface active agents are compounds that alter the surface prop­erties of liquid or semisolid foods, so as to produce a variety of ef­fects. For example, they might be used to make a product foamy or to reduce its tendency to foam. They might also be used to prevent a sticky food, such as peanut butter, from sticking to the container in which it is sold. Some common surface active agents are sodium and calcium stearoyl-2-lactylate, petroleum and other forms of wax, and the polysorbates.

Thickeners are used to increase the viscosity (resistance to flow) of food. They are added to salad dressings, cheese spreads, sauces, ice creams, frozen fruits, and other liquid and semisolid foods to produce some desired consistency. A number of natural gums, such as guar gum, gum arabic, and gum tragacanth, are especially popu­lar as thickeners. Various forms of starch used as thickeners include mono - and distarch phosphate and hydroxypropyl starch. Some syn­thetic compounds used for this purpose are the glycerol mono - and distearates, sodium and calcium stearoyl-2-lactylates, and polyglyc-erol monostearate (PGM).

Consumers in many parts of the world today have access to a huge variety of foods made possible by the use of food additives that enhance their color, flavor, taste, and other physical properties. Food chemists continue to look for new ways to make foods more interesting and more appealing to consumers in the future. One can safely predict that grocery stores of the mid-21st century will carry an even wider variety of products developed by ongoing research on food additives.