Food Facts For You!

 

Caring For and Recalibrating a Food Thermometer

• Did you know that placement of a food thermometer in a product impacts whether or not the temperature is recorded correctly?
• Did you know that thermometer-forks are now thought to be appropriate for checking food temperature while grilling?
• Did you know that pop-up timers popularly found in turkeys may not be accurate?

The United States Department of Agriculture has a wealth of information to help you answer questions such as these. Look in the Food Facts subject index under Thermometers for links to all sorts of helpful information…and read on for instructions on how to calibrate your dial-stem thermometer.

Using a dial stem thermometer. [These instructions are available as a hand out – check the Food Facts archives under Thermometer – and should be shared with any consumer who receives a dial stem thermometer as a teaching aid.]

• Remove the thermometer from the plastic sleeve.
• Place the metal stem 2 to 2 1/2" deep in thickest part of food with the pointed end first.
• Can be used in roasts, casseroles, and soups.
• Insert sideways into thin foods like burgers, steaks, or chops.
• Use to check the internal temperature of a food at, or near, the end of cooking time.
• Do not place the thermometer in food during cooking or grilling, the thermometer will melt.
• After checking the temperature, clean the metal stem only with soap and water, do not put the entire thermometer in water, dry and store in the plastic sleeve.

Calibrating a dial stem thermometer (UWEX model). Sometimes a dial stem thermometer loses calibration (it no longer registers temperature correctly). You can recalibrate most dial stem thermometers using ice water and boiling water. To recalibrate the monogrammed UWEX thermometers, proceed as follows-

1. Hold the thermometer head in one hand.
2. Slide the white sheath up the thermometer stem until the pocket clip touches the rear of the thermometer case.
3. Turn the sheath so that the pocket clip catches and turns the adjusting lug, which will in turn move the pointer.
4. Immerse the stem at least 2 inches into either ice water or boiling water and allow the temperature to stabilize (at least 30 seconds). The pointer should read 32-33°F while the stem is immersed into a vessel filled with crushed ice and water. The pointer should read 210-212°F when the stem is immersed into a vessel filled with boiling water.
5. Adjust the pointer as necessary and recheck your readings to ensure calibration.

 

Calibrating a thermometer with a hex (6-sided) nut under the dial: The USDA offers these instructions for calibrating a dial stem thermometer with a hex nut under the dial.

Ice Water. To use the ice water method, fill a large glass with finely crushed ice. Add clean tap water to the top of the ice and stir well. Immerse the food thermometer stem a minimum of 2 inches into the mixture, touching neither the sides nor the bottom of the glass. Wait a minimum of 30 seconds before adjusting. (For ease in handling, the stem of the food thermometer can be placed through the clip section of the stem sheath and, holding the sheath horizontally, lowered into the water.) Without removing the stem from the ice, hold the adjusting nut under the head of the thermometer with a suitable tool and turn the head so the pointer reads 32 °F.

 

Boiling Water. To use the boiling water method, bring a pot of clean tap water to a full rolling boil. Immerse the stem of a food thermometer in boiling water a minimum of 2 inches and wait at least 30 seconds. (For ease in handling, the stem of the food thermometer can be placed through the clip section of the stem sheath and, holding the sheath horizontally, lowered into the boiling water.) Without removing the stem from the pan, hold the adjusting nut under the head of the food thermometer with a suitable tool and turn the head so the thermometer reads 212 °F.

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Does Eating Grilled Meats Cause Cancer?

 

Summer in the United States means cookouts and family barbecues. Hamburgers, hotdogs, steaks and chicken are the epitome of the perfect weekend summer meal.

For years, there has been controversy over whether meat grilled on a charcoal grill could cause cancer.

According to officials of the American Cancer Society, eating excessive amounts of grilled meat or chicken can increase your risk of developing cancer. This is also true for meats pan-fried at high temperatures. Current research tells us that over cooked or burnt meats pose the greatest risk. Whether you are using red meat, poultry or seafood, substances in the muscle proteins of these foods react under very high heat to form carcinogenic compounds called heterocyclic amines (HCAs). HCAs can damage DNA, beginning the process of cancer development. Consumption of HCAs is mostly clearly linked to cancers of the colon and stomach. One study found that people who eat the most barbecued red meat (beef, pork and lamb) almost doubled their risk of colon polyps, compared to those who did not eat these foods. Colon polyps can develop into colon cancer. Some evidence also suggests that these carcinogenic compounds can travel through the bloodstream to other tissues. This would explain why HCAs could be a factor in breast cancer and other cancers.

Keep in mind, that grilling is okay – firing up the barbeque every week in the summer would not be expected to increase risk. Excessive consumption of grilled foods is the risk factor; and excessive consumption of charred foods is the real culprit. Keep in mind that just like everything in life, moderation is key. There is only an increased risk of cancer when excessive amounts are consumed. This is by no means an alert or warning to toss out your grills! You still can enjoy grilled meats, but just do it in moderation.

 

And there are a few steps that you can take to further decrease your risk:

• Cook at lower temperatures. Charring is most often associated with grilling over high heat/flames. If you are using a charcoal grill, allow the time for the coals to burn white-hot; and then place them to one side. Use the other side of your grill for grilling. This indirect heat will cook food at a lower temperature and prevent burning. Or, try moving the heat of the grill surface away from the embers. If you have a gas grill, regulate the heat to low or medium-low to control charring.
  
• Choose lean cuts of meat. Flare-ups are most often associated with fat dripping onto hot goals or a grill surface. Before grilling, trim external fat from steaks, roasts or chicken, and choose lean ground meat for grilling.
  
• Try marinating meat. The color and flavor that develop when cooking meat over high heat can add taste-appeal. You can marinate meat in a salt/sugar brine before grilling and encourage color and flavor development without high heat. A standard marinade consists of
  
• Choose meat from younger animals. The protein in older animals is more likely to have free fragments (amino acids) that will react to form heterocyclic amines. If you purchase meat in the grocery store, it will be difficult to tell the age of the animal; but if you raise animals yourself, reserve the meat from older animals for stewing, not grilling.
  
• Avoid eating burned or charred areas. Since heterocyclic amines are associated only with burned or charred areas, simply trim these areas off before cutting into a steak or chicken breast. If the burned area is on the skin of chicken, simply remove the skin and enjoy!
  
• Use a meat thermometer to tell when food is done. Once meat has reached the proper internal temperature to ensure safety, remove it from the grill. Over-cooking meat is also a way to produce harmful compounds.
  
• Try vegetables or fruits on the grill. Vegetables and fruits don't form heterocyclic amines on grilling. They also supply a whole range of cancer-fighting nutrients and phytochemicals. In fact, the natural phytochemicals in vegetables stimulate enzymes that can convert HCAs to an inactive, stable form that is easily eliminated from the body.

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Pet Food Chemical and Threat to Humans

 

Pet food chemical unlikely to pose threat to humans, experts say

By Donald G. Mcneil Jr. International Herald Tribune Wednesday, May 2, 2007

Toxicologists monitoring the American food supply for traces of melamine after it was found in imported ingredients in the contaminated pet food that has killed at least 16 dogs and cats and sickened thousands of others said Tuesday [May 1, 2007] that even if there were small amounts of it in the American food supply, it would be unlikely to pose much of a threat to humans.

Sampling thus far by the Food and Drug Administration for melamine, which has also been detected in chicken feed on some farms in Indiana, has not turned up the chemical in food meant for humans, and the trace amounts found in some poultry feed — and hog feed — would presumably be excreted or broken down by the animals before they were slaughtered, scientists and U.S. officials said. Also, a survey of poison control centers, veterans' hospitals and a sample of private hospitals across the country by the U.S. Centers for Disease Control and Prevention has found no increase in reports of kidney diseases, the most likely indicator of melamine poisoning, said Bernadette Burden, a CDC spokeswoman.

How the chemical — found in wheat gluten imported from China — could have poisoned cats and dogs remains something of a mystery, scientists said, because tests done decades ago on rats concluded that it was not very toxic. "Even when rats were loaded up with quite a lot, it caused stones or tumors over time, not acute kidney failure," said John Groves, a Princeton University chemistry professor. Other chemists speculated that the melamine could have been changed by the cooking of the pet food, by metabolism by bacteria or through combination with other, still unknown chemicals.

"I'm convinced that melamine can't do it by itself," said Richard Goldstein of Cornell University 's veterinary college. Toxicity trials, he said, were done with pure melamine, not manufacturing scrap, which could also contain cyanuric acid or other compounds. Also, said Jack Henion, a retired professor of toxicology and veterinary medicine at Cornell, cats — the first animals whose deaths from pet food were noticed — are unusually sensitive to kidney and urinary problems.

Melamine is a simple organic molecule that can be extracted from oil or coal, and is used as a resin in making plastics. It is found in plates, countertops, cabinet facings, even children's erasers. It contains large amounts of nitrogen. For that reason, it has apparently been used as a fertilizer, though it would presumably be harmless because plants would take up only the free nitrogen.

But in China , ground-up scraps from plastic-making have been added to grain and byproducts, like the sticky glutens used to thicken soups or help bread rise. It is presumably done to fool buyers into thinking they are getting a more nutritious product, because crude tests for protein in grain do not test for protein molecules, but for nitrogen, which proteins also have in abundance.

"It's blatant fraud in my view," Henion said. "There's no other good reason we know of to put melamine in." Some of those grain products have been sold to the United States for pet food. Last week, the drug agency said it would start requiring importers to provide proof of the safety of many more ingredients, including glutens and proteins of wheat, rice, corn, soy and mung bean.

 

Officials from the drug agency and the Agriculture Department estimated Tuesday that up to three million young broiler chickens on farms in Indiana ate feed contaminated with pet food containing melamine or related compounds in February. Most were slaughtered, sold and, presumably, eaten, said Kenneth Peterson, assistant administrator for field operations with the Food Safety and Inspection Service.

Even in those chickens, or in hogs on other farms, independent toxicologists and drug agency and agriculture department officials said, it was highly unlikely that the melamine could concentrate in amounts that could be harmful to humans. It would be mixed with other feeds, and much of it would be metabolized by animals and excreted. And it is not stored in fat as, for example, pesticides are. Also, most humans are not strictly carnivores, as cats are, so they would get lower doses.

"The dilution levels are enormous," David Acheson, the drug agency's assistant commissioner for food protection said Tuesday [May 1, 2007]. "When you multiply it all together, we think the likelihood of human illness is very low.”

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