28
Modern Food Microbiology
Division: Deuteromycota (the “imperfects,” anamorphs; perfect stages are unknown)
Class: Coelomycetes
Genus: Colletotrichum
Class: Hypomycetes (hyphae give rise to conidia)
Order: Hyphomycetales
Family: Moniliaceae
Genus: Alternaria
Aspergillus
Aureobasidium (Pullularia)
Botrytis
Cladosporium
Fusarium
Geotrichum
Helminthosporium
Monilia/Sclerotinium
Penicillium
Stachybotrys
Trichothecium
Some of the genera are listed below in alphabetical order.
Alternaria. Septate mycelia with conidiophores and large brown conidia are produced. The conidia
have both cross and longitudinal septa and are variously shaped. They cause brown to black rots of
stone fruits, apples, and figs. Stem-end rot and black rot of citrus fruits are also caused by species/strains
of this genus. This is a field fungus that grows on wheat. Additionally, it is found on red meats. Some
species produce mycotoxins (see Chapter 30).
Aspergillus. Chains of conidia are produced. Where cleistothecia with ascospores are developed, the
perfect stage of those found in foods is Emericella, Eurotium, or Neosartorya. Eurotium (the former
A. glaucus group) produces bright yellow cleistothecia, and all species are xerophilic. E. herbariorum
has been found to cause spoilage of grape jams and jellies.
41 Emericella produces white cleistothecia,
and E. nidulans is the teleomorph of Aspergillus nidulans. Neosartorya produces white cleistothecia
and colorless ascospores. N. fischeri is heat resistant, and resistance of its spores is similar to those
of Byssochlamys.
37 The aspergilli appear yellow to green to black on a large number of foods. Black
rot of peaches, citrus fruits, and figs is one of the fruit spoilage conditions produced. They are found
on country-cured hams and on bacon. Some species cause spoilage of oils, such as palm, peanut, and
corn. A. oryzae and A. soyae are involved in the shogu fermentation and the former in koji. A. glaucus
produces katsuobushi, a fermented fish product. The A. glaucus–A. restrictus group contains
storage fungi that invade seeds, soybeans, and common beans. A. niger produces β-galactosidase,
glucoamylase, invertase, lipase, and pectinase: and A. oryzae produces α-amylase. Several species
produce aflatoxins, and others produce ochratoxin A and sterigmatocystin (see Chapter 30).
Aureobasidium (Pullularia). Yeast-like colonies are produced initially. They later spread and produce
black patches. A. pullulans (Pullularia pullulans) is the most prevalent in foods. They are found in
shrimp, are involved in the “black spot” condition of long-term stored beef, and are common on fruits
and vegetables.
Modern Food Microbiology
Division: Deuteromycota (the “imperfects,” anamorphs; perfect stages are unknown)
Class: Coelomycetes
Genus: Colletotrichum
Class: Hypomycetes (hyphae give rise to conidia)
Order: Hyphomycetales
Family: Moniliaceae
Genus: Alternaria
Aspergillus
Aureobasidium (Pullularia)
Botrytis
Cladosporium
Fusarium
Geotrichum
Helminthosporium
Monilia/Sclerotinium
Penicillium
Stachybotrys
Trichothecium
Some of the genera are listed below in alphabetical order.
Alternaria. Septate mycelia with conidiophores and large brown conidia are produced. The conidia
have both cross and longitudinal septa and are variously shaped. They cause brown to black rots of
stone fruits, apples, and figs. Stem-end rot and black rot of citrus fruits are also caused by species/strains
of this genus. This is a field fungus that grows on wheat. Additionally, it is found on red meats. Some
species produce mycotoxins (see Chapter 30).
Aspergillus. Chains of conidia are produced. Where cleistothecia with ascospores are developed, the
perfect stage of those found in foods is Emericella, Eurotium, or Neosartorya. Eurotium (the former
A. glaucus group) produces bright yellow cleistothecia, and all species are xerophilic. E. herbariorum
has been found to cause spoilage of grape jams and jellies.
41 Emericella produces white cleistothecia,
and E. nidulans is the teleomorph of Aspergillus nidulans. Neosartorya produces white cleistothecia
and colorless ascospores. N. fischeri is heat resistant, and resistance of its spores is similar to those
of Byssochlamys.
37 The aspergilli appear yellow to green to black on a large number of foods. Black
rot of peaches, citrus fruits, and figs is one of the fruit spoilage conditions produced. They are found
on country-cured hams and on bacon. Some species cause spoilage of oils, such as palm, peanut, and
corn. A. oryzae and A. soyae are involved in the shogu fermentation and the former in koji. A. glaucus
produces katsuobushi, a fermented fish product. The A. glaucus–A. restrictus group contains
storage fungi that invade seeds, soybeans, and common beans. A. niger produces β-galactosidase,
glucoamylase, invertase, lipase, and pectinase: and A. oryzae produces α-amylase. Several species
produce aflatoxins, and others produce ochratoxin A and sterigmatocystin (see Chapter 30).
Aureobasidium (Pullularia). Yeast-like colonies are produced initially. They later spread and produce
black patches. A. pullulans (Pullularia pullulans) is the most prevalent in foods. They are found in
shrimp, are involved in the “black spot” condition of long-term stored beef, and are common on fruits
and vegetables.