IB. Composition and Spoilage of Red Meats

Question 1

• spoilage within muscle tissue due to slow cooling of carcasses

Answer 1

“sours” or “bone taint”

Question 2

• cause meat spoilage stored at ambient temperature.

Answer 2

Clostridium perfringens and
Enterobacteriaceae

Question 3

• produce a whiskery, airy, or cottony gray to black growth on beef.

Answer 3

Thamnidium, Mucor, and Rhizopus

Question 4

• black spot
• white spot
• green patches

Answer 4

Cladosporidium, Sporotrichum and Chrysosporium , Pennecilium

Question 5

• spoilage microorganisms in poultry muscle

Answer 5

Pseudomonas, Aeromonas, Shewanella putrefaciens

Question 6

• has the ability to make hydrogen sulfide, dimethyl sulfide, and
methyl mercaptan that causes spoilage

Answer 6

S. putrefaciens

Question 7

• molecule present in crustacean shellfish

Answer 7

trimethylamine oxide

Question 8

• breakdown proteins and cause tissue softening and development
of volatile off-odors in crustaceans

Answer 8

cathepsin-like enzyme

Question 9

Proteolytic and Lipolytic Activities

Answer 9

• Pseudomonas and other aerobic spoilage bacteria produce proteolytic enzymes
• proteolysis occurs in populations of 108 CFU/cm2

Question 10

• occurs when unsaturated fatty acids react with oxygen

Answer 10

oxidative rancidity of fat

Question 11

Spoilage of Adipose Tissue

Answer 11

• consists of insoluble fat, which cannot be used for microbial growth until it is
broken down and emulsified

Question 12

Spoilage under Anaerobic Conditions

Answer 12

• LAB dominate the spoilage microflora when oxygen is excluded