569 FLINT
flavonol. (flavon-3-ol). A flavonoid plant pig- “Flectol” [Solutia]. TM for polymerized 1,2-
ment giving ivory and yellow colors to flowers. Not dihydro-2,2,4-trimethylquinoline.
identical with flavanol.
Use: Rubber antioxidant to retard oxidation, deterio-
ration, and normal aging in belts, tires, hoses, re-
tread, rubber, and general mechanics.
flavoprotein. An enzyme containing a FMN or
FAD as a tightly bound prosthetic group.
Fleming, Sir Alexander. (1881–1955). A
See flavin enzyme.
Scottish biochemist and bacteriologist who discov-
ered (1928) the bactericidal properties of molds pro-
flavor. (1) The simultaneous physiological and
duced from the plant Penicillium notatum. A broad
psychological response obtained from a substance
spectrum of antibiotics has been developed from this
in the mouth that includes the senses of taste (salty,
discovery.
sour, bitter, sweet), smell (fruity, pungent), and feel.
See antibiotic.
The sense of feel as related to flavor encompasses
only the effect of chemical action on the mouth
“Flexamine G” [Uniroyal]. TM for a mixture
membranes such as heat from pepper, coolness from
of N,N
′
-diphenyl-p-phenylenediamine and a com-
peppermint, and the like (Institute of Food Technol-
plex diarylamine-ketone reaction product.
ogists). No reliable correlation of taste with chemi-
Properties: Brownish-gray granules. D 1.20, melt-
cal structure has yet been possible. Flavor is a criti-
ing range 75–90C. “Flexamine S” is soluble in ace-
cal factor in the acceptability of foods, medicines,
tone, benzene, and ethylene dichloride and insoluble
confectionery, and beverages. Flavors are used in
in water and gasoline.
insect and animal baits to induce ingestion of the
Use: Antioxidant used in tires, camelback, wire insu-
bait, also to prevent rodent attack on organic materi-
lation, neoprene belting, and soles.
als, e.g., tributyl tin in cable covers. Substances that
affect flavor often have a synergistic effect (for
“Flexol” [Dow]. TM for a series of plasticizers
example, monosodium glutamate and certain nucle-
and stabilizers including phthalates, adipates, poly-
otides). Sodium chloride is classed as a seasoning
alkylene glycol derivatives, polymeric epoxies, de-
agent.
canoates, octoates, hexoates, tri(2-ethylhex-
See potentiator; enhancer.
yl)phosphate, and dibutyltin dilaurate.
(2) Any substance or mixture of substances that
Use: Film and sheeting; flooring; coated fabrics;
contributes a positive taste to a food product, such as
wire, cable and other extrusions; organosols; plasti-
vanillin, cacao, and fruit extracts among natural
sols and plastigels; lacquers; and rubbers.
products, together with numerous synthetic com-
pounds that imitate or duplicate these tastes. Unde-
“Flexomer” [Dow]. TM for very low density,
sirable or off flavors occur in milk, meat, and other
extremely flexible, olefin copolymers that bridge
food products as a result of improper preparation,
the gap between plastics and rubber.
oxidation, and incipient rancidity. There are over
Use: For hose and tubing, ice and frozen-food bags,
1500 flavoring materials listed as food additives
food packaging and stretch wrap, and impact modi-
under provisions of the Food, Drug, and Cosmetics
fiers when blended with other polymers.
Act.
See odor.
“Flexsil” [Ametek]. TM for for a high silica
refractory cloth filter designed to extract dross, slag,
Flavor Extract Manufacturers Association.
refractory particles, and nonmetallic inclusions
(FEMA). The FEMA makes recommendations
from molten metals. An important property is its
to the FDA on safety aspects of flavoring materials.
chemically active surface.
Membership is composed of firms engaged in the
Use: In-mold filtration of gray, malleable, or white,
manufacture and sale of flavoring extracts. It is lo-
compacted graphite, and ductile cast irons, as well as
cated at 1620 I Street, NW, Ste. 925, Washington
nonferrous aluminum- and copper-based alloys.
DC 20006.
“Flexzone” [Uniroyal]. TM for a series of an-
flax. Bast fibers, approximately 20 inches long,
tiozonants, antioxidants, and stabilizers based on p-
obtained from the stems of the linseed plant, Linum
phenylenediamine.
usitatissimum. Stronger and more durable than cot-
ton. Combustible.
flint. A crystalline form of native silica or quartz.
Use: Apparel fabrics (linens), thread, rope, twine,
Properties: Smoky-gray, brownish, blackish or dull
cigarette paper, duplicating papers.
yellowish in color; waxy to greasy luster. Mohs
hardness 6.5–7, d 2.60–2.65. More easily soluble in
flaxseed oil. See linseed oil.
hot caustic alkali than is crystallized quartz.
Occurrence: Europe, U.S.
flecainide. Use: Abrasive; balls for ball mills; paint extender;
CAS: 54143-55-4. mf: C
17
H
20
F
6
N
2
O
3
. filler for fertilizer, insecticides, rubber, plastics, and
Hazard: Human systemic effects. road asphalt; ceramics; chemical tower packing.