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Is Pink Turkey Meat Safe? |
The color pink in cooked
turkey meat raises a "red flag" to many diners and cooks. Conditioned
to be wary of cooked fresh pork that looks pink, they question
the safety of cooked poultry and other meats that have a rosy
blush.
Numerous callers to the USDA Meat and Poultry Hotline report
being alarmed when seeing "pink." To them, it means "unsafe"
or "under-done."
"I cooked my turkey until done according to the directions,
but when I sliced the breast meat, it was still pink near the
bone," said an Oklahoma caller. "Is it safe?"
"We had a big family argument at Thanksgiving dinner. Aunt
Mildred wouldn't eat the turkey because it looked pink," reported
the beleaguered cook from a Wisconsin family.
The color of cooked poultry is not always a sure sign of its
safety. Only by using a food thermometer can one accurately
determine that poultry has reached a safe minimum internal temperature
of 165 °F throughout the product. Turkey can remain pink
even after cooking to a safe minimum internal temperature of 165
°F. The meat of smoked turkey is always pink.
To understand some of the causes of "pinking" or "pinkening"
in fresh turkey, it’s important to know first what gives
meat its natural color.
Why is Poultry Lighter in Color Than Beef?
The protein myoglobin is the major pigment found in
all vertebrates and can exist in various forms which determine
the resulting meat color. The major reason that poultry meat
is much lighter in color than beef is that it is dramatically
lower in myoglobin. Also, as an animal becomes older, its myoglobin
content usually increases. Turkeys today are young — 4
to 5 months old at the time of slaughter.
Why Are White & Dark Meat of Poultry Different
Colors?
The pink, red or white coloration of meat is due primarily to
oxygen-storing myoglobin which is located in the muscle cells
and retains the oxygen brought by the blood until the cells
need it. To some extent, oxygen use can be related to the bird’s
general level of activity: muscles that are exercised frequently
and strenuously — such as the legs — need more oxygen,
and they have a greater storage capacity than muscles needing
little oxygen. Turkeys do a lot of standing around, but little
if any flying, so their wing and breast muscles are white; their
legs, dark.
What Causes Well-Done Meat to Be Pink?
- Chemical Changes During Cooking.
Scientists have found that pinkness occurs when gases in
the atmosphere of a heated gas or electric oven react chemically
with hemoglobin in the meat tissues to give poultry a pink
tinge. They are the same substances that give red color
to smoked hams and other cured meats.
The presence of high levels of myoglobin, or some of its
redder forms due to incomplete denaturation during heat
processing, can account for poultry having a pink to red
color similar to that of an undercooked product.
- Natural Presence of Nitrites.
Nitrites are commonly used to produce a desired pink color
in traditionally cured meats such as ham or bologna. So
it follows that the natural presence of nitrates and nitrites,
either in the feed or water supply, used in the production
of poultry are a factor in nitrite levels in the birds.
One study found that during 40 hours of storage at 40 °F,
naturally occurring microorganisms converted nitrate to
nitrite. It also found that the local water supply had nitrate
and, thus, it could serve as a nitrate source during processing.
- Young Age of Meat.
Often meat of younger birds shows the most pink because
their thinner skins permit oven gases to reach the flesh.
The amount of fat in the skin also affects the amount of
pink color. Young birds or animals also lack the shield
of a fat covering.
- Grilling.
Meat and poultry grilled or smoked outdoors can also look
pink, even when well done. There may be a pink-colored rim
about one-half inch wide around the outside of the cooked
meat. The meat of commercially smoked turkeys is usually
pink because it is prepared with natural smoke and liquid
smoke flavor.
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Last Modified:
April 27, 2006 |
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