There are three types of microorganisms that cause food spoilage -- yeasts, moulds and bacteria.
Bacteria are round, rod or spiral shaped microorganisms. Bacteria may grow under a wide variety of conditions. There are many types of bacteria that cause spoilage. They can be divided into: spore-forming and non-spore-forming. Bacteria generally prefer low acid foods like vegetables and meat. In order to destroy bacteria spores in a relatively short period of time, low acid foods must be processed for the appropriate length of time at 116°C (240°F) in a pressure canner. (Temperatures higher than 100°C [212°F] can be obtained only by pressure canning.)
Microorganisms involved in food spoilage
Microorganisms involved in food spoilage(Other than Canned Foods) with some examples of causative organisms
Food
Type of Spoilage
Microorganisms involved
Bread
Mouldy
Rhizopus nigricans
Penicillium
Aspergillus niger
Ropy
Bacillus subtilis
Maple sap and syrup
Ropy
Enterobacter aerogenes
Yeasty
Saccharomyces
Zygosaccharomyces
Pink
Micrococcus roseus
Mouldy
Aspergillus
Penicillium
Fresh fruits and vegetables
Soft rot
Rhizopus
Erwinia
Gray mold rot
Botrytis
Black mold rot
A. niger
Pickles, sauerkraut
Film yeasts, pink yeasts
Rhodotorula
Fresh meat
Putrefaction
Alcaligenes
Clostridium
Proteus vulgaris
Pseudomonas fluorescens
Cured meat
Mouldy
Aspergillus
Rhizopus
Penicillium
Souring
Pseudomonas
Micrococcus
Greening, slime
Lactobacillus
Leuconostoc
Fish
Discoloration
Pseudomonas
Putrefaction
Alcaligenes
Flavobacterium
Eggs
Green rot
P. fluorescens
Colorless rots
Pseudomonas
Alcaligenes
Black rots
Proteus
Concentrated orange juice
"Off" flavor
Lactobacillus
Leuconostoc
Acetobacter
Poultry
Slime, odor
Pseudomonas
Alcaligenes
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