Beef Nutritional Profile

8/18/2019 Beef Nutritional Profile

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Nutritional Profile*

Energy value (calories per serving): Moderate

Protein: High

Fat: Moderate

Saturated fat: High

Cholesterol: Moderate

Carbohydrates: None

Fiber: None

Sodium: Low

Major vitamin contribution: B vitamins

Major mineral contribution: Iron, phosphorus, zinc

About the Nutrients in This Food

Like fish, pork, poultry, milk, and eggs, beef has high-quality proteins,with sufficient amounts of all the essential amino acids. Beef fat is slightlymore highly saturated than pork fat, but less saturated than lamb fat. Allhave about the same amount of cholesterol per serving.

Beef is an excellent source of B vitamins, including niacin, vitaminB6 , and vitamin B12, which is found only in animal foods. Lean beef pro-vides heme iron, the organic iron that is about five times more useful to thebody than nonheme iron, the inorganic form of iron found in plant foods.Beef is also an excellent source of zinc.

One four-ounce serving of lean broiled sirloin steak has nine gramsfat (3.5 g saturated fat), 101 mg cholesterol, 34 g protein, and 3.81 mg iron(21 percent of the RDA for a woman, 46 percent of the RDA for a man).One four-ounce serving of lean roast beef has 16 g fat (6.6 g saturated fat),92 mg cholesterol, and 2.96 mg iron (16 percent of the RDA for a woman,37 percent of the RDA for a man).

The Most Nutritious Way to Serve This FoodWith a food rich in vitamin C. Ascorbic acid increases the absorption ofiron from meat.

* These values apply to lean cooked beef.


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Diets That May Restrict or Exclude This Food

Controlled-fat, low-cholesterol dietLow-protein diet (for some forms of kidney disease)

Buying This Food

Look for: Fresh, red beef. The fat should be white, not yellow.Choose lean cuts of beef with as little internal marbling (streaks of fat) as possible. The

leanest cuts are flank steak and round steak; rib steaks, brisket, and chuck have the most fat.USDA grading, which is determined by the maturity of the animal and marbling in meat, isalso a guide to fat content. U.S. prime has more marbling than U.S. choice, which has moremarbling than U.S. good. All are equally nutritious; the difference is how tender they are,which depends on how much fat is present.

Choose the cut of meat that is right for your recipe. Generally, the cuts from the cen-

ter of the animal’s back—the rib, the T-Bone, the porterhouse steaks—are the most tender.They can be cooked by dry heat—broiling, roasting, pan-frying. Cuts from around the legs,the underbelly, and the neck—the shank, the brisket, the round—contain muscles used formovement. They must be tenderized by stewing or boil ing, the long, moist cooking methodsthat break down the connective tissue that makes meat tough.

Storing This Food

Refrigerate raw beef immediately, careful ly wrapped to prevent its drippings from contami-nating other foods. Refrigeration prolongs the freshness of beef by slowing the natural multi-plication of bacteria on the meat surface. Unchecked, these bacteria wil l convert proteins and

other substances on the surface of the meat to a slimy film and change meat’s sulfur-contain-ing amino acids methionine and cystine into smelly chemicals called mercaptans. When themercaptans combine with myoglobin, they produce the greenish pigment that gives spoiledmeat its characteristic unpleasant appearance.

Fresh ground beef, with many surfaces where bacteria can live, should be used within24 to 48 hours. Other cuts of beef may stay fresh in the refrigerator for three to five days.

Preparing This Food

Trim the beef carefully. By judiciously cutting away all visible fat you can significantly

reduce the amount of fat and cholesterol in each serving.When you are done, clean all utensils thoroughly with soap and hot water. Wash your

cutting board, wood or plastic, with hot water, soap, and a bleach-and-water solution. Forultimate safety in preventing the transfer of microorganisms from the raw meat to otherfoods, keep one cutting board exclusively for raw meats, fish, and poultry, and a second onefor everything else. Finally, don’t forget to wash your hands.


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What Happens When You Cook This Food

Cooking changes the appearance and flavor of beef, alters nutritional value, makes it safer,and extends its shelf life.

Browning meat after you cook it does not “seal in the juices,” but it does change the fla-

vor by caramelizing sugars on the surface. Because beef’s only sugars are the small amountsof glycogen in the muscles, we add sugars in marinades or basting liquids that may also con-tain acids (vinegar, lemon juice, wine) to break down muscle fibers and tenderize the meat.(Browning has one minor nutritional drawback. It breaks amino acids on the surface of themeat into smaller compounds that are no longer useful proteins.)

When beef is cooked, it loses water and shrinks. Its pigments, which combine withoxygen, are denatured (broken into fragments) by the heat and turn brown, the natural colorof well-done meat.

At the same time, the fats in the beef are oxidized. Oxidized fats, whether formed incooking or when the cooked meat is stored in the refrigerator, give cooked meat a character-istic warmed-over flavor. Cooking and storing meat under a blanket of antioxidants—catsup

or a gravy made of tomatoes, peppers, and other vitamin C-rich vegetables—reduces theoxidation of fats and the intensity of warmed-over flavor. Meat reheated in a microwaveoven also has less warmed-over flavor.

An obvious nutritional benefit of cooking is the fact that heat lowers the fat content ofbeef by liquifying the fat so it can run off the meat. One concrete example of how well thisworks comes from a comparison of the fat content in regular and extra-lean ground beef.According to research at the University of Missouri in 1985, both kinds of beef lose masswhen cooked, but the lean beef loses water and the regular beef loses fat and cholesterol.Thus, while regular raw ground beef has about three times as much fat (by weight) as rawground extra-lean beef, their fat varies by only 5 percent after broiling.

To reduce the amount of fat in ground beef, heat the beef in a pan until it browns. Then

put the beef in a colander, and pour one cup of warm water over the beef. Repeat with asecond cup of warm water to rinse away fat melted by heating the beef. Use the ground beefin sauce and other dishes that do not require it to hold together.

Finally, cooking makes beef safer by killing Salmonella and other organisms in themeat. As a result, cooking also serves as a natural preservative. According to the USDA, largepieces of fresh beef can be refrigerated for two or three days, then cooked and held safely foranother day or two because the heat of cooking has reduced the number of bacteria on thesurface of the meat and temporarily interrupted the natural cycle of deterioration.

How Other Kinds of Processing Affect This Food

Aging. Hanging fresh meat exposed to the air, in a refrigerated room, reduces the moisturecontent and shrinks the meat slightly. As the meat ages enzymes break down muscle pro-teins, “tenderizing” the beef.

Canning. Canned beef does not develop a warmed-over flavor because the high tempera-tures in canning food and the long cooking process alter proteins in the meat so that they act

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as antioxidants. Once the can is open, however, the meat should be protected from oxygenthat will change the flavor of the beef.

Curing. Salt-curing preserves meat through osmosis, the physical reaction in which liquidsflow across a membrane, such as the wall of a cel l, from a less dense to a more dense solution.The salt or sugar used in curing dissolves in the liquid on the surface of the meat to make asolution that is more dense than the liquid inside the cells of the meat. Water flows out ofthe meat and out of the cells of any microorganisms living on the meat, killing the microor-ganisms and protecting the meat from bacterial damage. Salt-cured meat is much higher insodium than fresh meat.

Freezing. When you freeze beef, the water inside its cells freezes into sharp ice crystals thatcan puncture cell membranes. When the beef thaws, moisture (and some of the B vitamins)will leak out through these torn cell walls. The loss of moisture is irreversible, but some ofthe vitamins can be saved by using the drippings when the meat is cooked. Freezing mayalso cause freezer burn—dry spots left when moisture evaporates from the surface of themeat. Waxed freezer paper is designed specifically to hold the moisture in meat; plastic wrap

and aluminum foil are less effective. NOTE: Commercially prepared beef, which is frozenvery quickly at very low temperatures, is less likely to show changes in texture.

Irradiation. Irradiation makes meat safer by exposing it to gamma rays, the kind of high-energy ionizing radiation that kills l iving cells, including bacteria. Irradiation does not changethe way meat looks, feels or tastes, or make the food radioactive, but it does alter the structureof some naturally occurring chemicals in beef, breaking molecules apart to form new com-pounds called radiolytic products (RP). About 90 percent of RPs are also found in nonirradiatedfoods. The rest, called unique radiolytic products (URP), are found only in irradiated foods.There is currently no evidence to suggest that URPs are harmful; irradiation is an approvedtechnique in more than 37 countries around the world, including the United States.

Smoking. Hanging cured or salted meat over an open fire slowly dries the meat, kills micro-organisms on its surface, and gives the meat a rich, “smoky” flavor that varies with the woodused in the fire. Meats smoked over an open fire are exposed to carcinogenic chemicals inthe smoke, including a-benzopyrene. Meats treated with “artificial smoke flavoring” are not,since the flavoring is commercially treated to remove tar and a-benzopyrene.

Medical Uses and/or Benefits

Treating and/or preventing iron deficiency. Without meat in the diet, it is vir tual ly impossiblefor an adult woman to meet her iron requirement without supplements. One cooked 3.5-

ounce hamburger provides about 2.9 mg iron, 16 percent of the RDA for an adult woman ofchildbearing age.

Possible anti-diabetes activity. CLA may also prevent type 2 diabetes, also called adult-onsetdiabetes, a non-insulin-dependent form of the disease. At Purdue University, rats bred todevelop diabetes spontaneously between eight and 10 weeks of age stayed healthy whengiven CLA supplements.


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Adverse Effects Associated with This Food

Increased risk of heart disease. Like other foods from animals, beef contains cholesterol andsaturated fats that increase the amount of cholesterol circulating in your blood, raising yourrisk of heart disease. To reduce the risk of heart disease, the National Cholesterol Education

Project recommends following the Step I and Step II diets.The Step I diet provides no more than 30 percent of total daily calories from fat, no

more than 10 percent of total daily calories from saturated fat, and no more than 300 mgof cholesterol per day. It is designed for healthy people whose cholesterol is in the range of200–239 mg/dL.

The Step II diet provides 25–35 percent of total calories from fat, less than 7 percentof total calories from saturated fat, up to 10 percent of total calories from polyunsaturatedfat, up to 20 percent of total calories from monounsaturated fat, and less than 300 mg cho-lesterol per day. This stricter regimen is designed for people who have one or more of thefollowing conditions:

Existing cardiovascular diseaseHigh levels of low-density lipoproteins (LDLs, or “bad” cholesterol) or lowlevels of high-density lipoproteins (HDLs, or “good” cholesterol)ObesityType 1 diabetes (insulin-dependent diabetes, or diabetes mellitus)Metabolic syndrome, a.k.a. insulin resistance syndrome, a cluster of risk fac-tors that includes type 2 diabetes (non-insulin-dependent diabetes)

Increased risk of some cancers. According the American Institute for Cancer Research, a diethigh in red meat (beef, lamb, pork) increases the risk of developing colorectal cancer by 15

percent for every 1.5 ounces over 18 ounces consumed per week. In 2007, the National Can-cer Institute released data from a survey of 500,000 people, ages 50 to 71, who participatedin an eight-year AARP diet and health study identifying a higher risk of developing cancerof the esophagus, liver, lung, and pancreas among people eating large amounts of red meatsand processed meats.

Food-borne illness. Improperly cooked meat contaminated with E. coli O157:H7 has beenlinked to a number of fatalities in several parts of the United States. In addition, meats con-taminated with other bacteria, viruses, or parasites pose special problems for people with aweakened immune system: the very young, the very old, cancer chemotherapy patients, andpeople with HIV. Cooking meat to an internal temperature of 140°F should destroy Salmo-nella and Campylobacter jejuni; 165°F, the E. coli organism; and 212°F, Listeria monocytogenes.

Antibiotic sensitivity. Cattle in the United States are routinely given antibiotics to protectthem from infection. By law, the antibiotic treatment must stop three days to several weeksbefore the animal is slaughtered. Theoretically, the beef should then be free of antibioticresidues, but some people who are sensitive to penicill in or tetracycline may have an allergicreaction to the meat, although this is rare.

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Antibiotic-resistant Salmonella and toxoplasmosis. Cattle treated with antibiotics may pro-duce meat contaminated with antibiotic-resistant strains of Salmonella, and all raw beefmay harbor ordinary Salmonella as well as T. gondii, the parasite that causes toxoplasmosis.Toxoplasmosis is particularly hazardous for pregnant women. It can be passed on to the fetusand may trigger a series of birth defects including blindness and mental retardation. Both

Salmonella and the T. gondii can be eliminated by cooking meat thoroughly and washing allutensils, cutting boards, and counters as well as your hands with hot soapy water beforetouching any other food.

Decline in kidney function. Proteins are nitrogen compounds. When metabolized, theyyield ammonia, which is excreted through the kidneys. In laboratory animals, a sustainedhigh-protein diet increases the flow of blood through the kidneys, accelerating the naturalage-related decline in kidney function. Some experts suggest that this may also occur inhuman beings.

Food/Drug InteractionsTetracycline antibiotics (demeclocycline [Declomycin], doxycycline [Vibtamycin], methacycline[Rondomycin], minocycline [Minocin], oxytetracycline [Terramycin], tetracycline [Achromycin V, Panmycin, Sumycin] ). Because meat contains iron, which binds tetracyclines into com-pounds the body cannot absorb, it is best to avoid meat for two hours before and after takingone of these antibiotics.

Monoamine oxidase (MAO) inhibitors. Meat “tenderized” with papaya or a papain powdercan interact with the class of antidepressant drugs known as monoamine oxidase inhibi-tors. Papain meat tenderizers work by breaking up the long chains of protein molecules.One by-product of this process is tyramine, a substance that constructs blood vessels and

raises blood pressure. MAO inhibitors inactivate naturally occurring enzymes in your bodythat metabolize tyramine. If you eat a food such as papain-tenderized meat, which is highin tyramine, while you are taking a MAO inhibitor, you cannot effectively eliminate thetyramine from your body. The result may be a hypertensive crisis.

Theophylline. Charcoal-broiled beef appears to reduce the effectiveness of theophyllinebecause the aromatic chemicals produced by burning fat speed up the metabolism of the-ophylline in the liver.

Beef Nutritional Profile

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