Fundamental Food Microbiology, Third Edition - Fuad Fathir

502 FUNDAMENTAL FOOD MICROBIOLOGY
chocolate, instant tea, fish, sausage casings, and many others, and to reduce sulfite
in wines. In the future, the use of H 2O 2 in foods is expected to increase.
D. Epoxides (Ethylene Oxide, Propylene Oxide)
Ethylene oxide and propylene oxide are used as fumigants to destroy microorganisms
(and insects) in grains, cocoa powder, gums, nuts, dried fruits, spices, and packaging
materials. They are germicidal and effective against cells, spores, and viruses. Ethylene
oxide is more effective. Epoxides are alkylating agents and react with various
groups (e.g., –SH, –NH 2, and –OH) in cellular macromolecules, particularly structural
proteins and enzymes, adversely affecting their functions. They can react with
some food components, such as chlorides, and form toxic compounds that can remain
as residue in treated foods. They can be toxic at high concentrations (as residue),
particularly to people who are sensitive to them.
E. Acids
Acetic, propionic, lactic, citric, benzoic, and sorbic acids are discussed in Chapter
16 and Chapter 35.
F. Parabens
Methyl and propyl esters of p-hydroxybenzoic acids are discussed in Chapter 35.
G. Bacteriocins of Lactic Acid Bacteria
Bacteriocins of food-grade lactic acid bacteria, with special reference to nisin and
pediocin AcH, are discussed in Chapter 16.
H. Diacetyl
Diacetyl is discussed in Chapter 16.
I. CO 2
CO 2 is discussed in Chapter 36.
J. Butylated Hydroxyanisol (BHA), Butylated Hydroxytoluene (BHT),
and t-Butyl Hydroquinone (TBHQ)
BHA, BHT, and TBHQ are primarily used at 200 ppm or less as antioxidants to
delay oxidation of unsaturated lipids. Additionally, they have antimicrobial properties
and thus can be regarded as indirect antimicrobials. In concentrations of 50 to
400 ppm, BHA inhibits growth of many Gram-positive and Gram-negative bacteria;
however, some species may be resistant to it. They also effectively prevent growth
and toxin production by molds and growth of yeasts, but BHA seems to be more