Section I. CAUSES OF OFF-FLAVORS IN MILK
a. Duty of 91R20. As a 91R20 veterinary food inspection specialist, you must
verify the presence of deteriorative conditions in dairy products. As appropriate, you will
confirm inspection findings indicating the presence of deteriorative subsistence.
Deteriorative conditions include abnormal color, off-odor, abnormal texture or
consistency, 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
c. Classifying Off-Flavors. The following paragraphs of this section classify
off-flavors in milk according to their causes.
There are four kinds of heat-induced flavor alterations: cooked or sulfurous,
heated or rich, caramelized, and scorched.
a. From Pasteurization. Pasteurization imparts a slight cooked or sulfurous
flavor to milk. The flavor is more pronounced if higher temperatures are used.
b. From Refrigerator Storage. A rich or heated flavor results after milk has
been stored at refrigerator temperatures for several days.
c. From an Autoclave. Retorted and autoclaved milk often has a caramelized
d. From High Temperature Processing. A scorched flavor can result from
exceptionally large amounts of "burn on" in a heat exchanger. This flavor also occurs in
dry milk powders subjected to abnormally high temperature processing.