402
APPENDIX A
Glossary
Acid: A substance with a pH of less than 7.0.
Acids, strong: Substances that release high
concentrations of hydrogen ions in a solu-
tion giving a low pH; examples are muriatic
and sulfuric acids.
Acids, weak: Substances with a moderately
low pH; examples are organic acids, such as
acetic and hydroxyacetic acids.
Adulteration: The addition of an improper,
foreign substance.
Aerobic: The ability to live and reproduce
only in the presence of oxygen.
Air screen: A unit that provides a strong
downward movement of air at doors to pre-
vent refrigeration loss and insect entry.
Alkali: A substance with a pH of more
than 7.0.
Alkalies, strong: Substances that release
high concentrations of hydroxyl ions in a
solution giving a high pH; examples are
sodium hydroxide and potassium hydroxide.
Alkalies, weak: Substances that release
moderate to low concentrations of hydroxyl
ions in a solution giving a moderately high
pH; examples are sodium bicarbonate and
sodium tetraphosphate.Allergen: A substance that causes the
human immune system to trigger and work
against itself.Anaerobic: The ability to live and repro-
duce in the absence of oxygen.Antibiotic: A compound produced by a
microorganism that interferes with the growth
of another microbe.Antimicrobial: A substance that prevents
the proliferation of microorganisms.Antiseptic: A chemical substance used to
interfere with or inhibit the growth of cer-
tain microorganisms.AW: The unit of measurement for water
requirement of microorganisms.Bacilli: Rod-shaped bacteria.Bacteria: Single-celled microorganisms
that decompose matter, resulting in product
spoilage and/or foodborne illness.Bactericide: A chemical substance that will
kill certain bacterial cells.