SPOILAGE IN ANIMAL PRODUCTS
Fresh animal product are perishable, so they need to be chilled and stored in ice or a refrigerator
(0 – 4o C). In this condition, means that psychrotrophs become dominant and are the primary cause of
spoilage. If these fresh product are mishandled and allowed to remain at room temperature, a more
diverse flora may be present, since not only will many psychrotrophs grow, but also there will be some
In general the muscle tissue of live, healthy animal is sterile. The organism that present in the
carcass are concentrated in lymph nodes. After slaughter, the defense mechanism ares lowed or halted.
This enables bacteria to multiply and spread throughout the tissues.
Spoilage of meat due to the growth and metabolism of large numbers of microorganisms on the
surface or the interior. Most spoilage is on the surface.
The most common indications of spoilage are : 1) off-odor and slime, usually due to growth of
aerobic bacteria on the cut surfaces of meat ; 2) fungal growth , which is favored at water activity too
low for bacterial growth; 3) bone-taint, or deep spoilage, due anaerobic or facultative microorganism
and 4) discoloration, primarily due to alterations of myoglobin, the muscle pigment.
There are some differences in the spoilage patterns fresh and cured meat. Generally, cooked
meat is spoilage by a few types of organisms that can survive the cooking, or that gain access to the
cooked product. Fresh, chilled meat meat is indicated by off-odor and slime due to Pseudomonas,
Acinetobacter and Alcaligenes. Cured meat become sour due to the activity of Micrococcus,
Lactobacillus and Microbacterium species.
Immediately after processing, any of several hundred species of microorganism might be found.
However, because the poultry is chilled held in cold storage, psychrothropic microorganism
predominate and cause deterioration. The main defect are off odor, which appear at a bacterial load
between 106 – 108 pe