LESSON 3
DETERIORATION OF WATERFOODS
Section I. DETERIORATIVE CONDITIONS IN WATERFOODS
3-1.
INTRODUCTION
a. Duty of 91R20. As a 91R20 veterinary food inspection specialist, you must
verify the presence of deteriorative conditions in waterfoods. As appropriate, you will
confirm inspection findings indicating the presence of deteriorative subsistence.
Deteriorative conditions include abnormal color, off-odor, abnormal texture, off-flavor,
foreign material, and others.
b. Duty of 91R10. The 91R10 veterinary food inspection specialist's findings do
not identify the deteriorative condition. Rather the 91R10 notes abnormalities of the
inspected product which may or may not indicate the presence of a deteriorative
condition.
3-2.
MICROBIAL SPOILAGE
a. Relatively Rapid Deterioration. From the moment fish are taken from the
water, a series of deteriorative changes start to occur which eventually will render the
fish unmarketable. Since these changes occur relatively rapidly, fish are probably the
most perishable of all flesh foods. Microbiological action produces the most extensive
of the deteriorative changes.
b. Product Examination by the Inspector. Examine the product and note
abnormal color(s), odor(s), and/or texture(s) typical of microbial deterioration. Microbial
spoilage may be caused by bacteria, mold, and/or yeasts. The particular color, odor, or
texture change(s) involved will depend upon the type or species of microorganism
involved.
c. Caution to the Inspector and Appropriate Action. If microbial spoilage is
suspected, THE INSPECTOR SHOULD NOT TASTE THE PRODUCT. He should
contact the veterinary officer for further examination of the product.
d. Color Changes. The following color changes may indicate microbial
spoilage: red, pink, chocolate brown, yellowish green, black, brown, and so forth
e. Odor Changes. The following odor changes have been associated with
microbial deterioration: muddy, musty, sour, putrid, soapy, milky, fecal, brine-like,
sweet, yeasty, ammonia, hydrogen sulfide, fruity, dishraggy, wet hair, wet dog, and so forth.
f. Changes in Texture. The following textural changes may be associated with
microbial deterioration: slimy, foamy, bubbly, soft, honeycombed, turbid, and jellylike.
MD0723
3-2