Have you ever wondered why bacon is pink while pork is white? Or why we used to be told to cook pork until it was completely white?
The answer lies in the science of meat and cooking. In this article, we’ll explore the reasons behind the color differences in bacon and pork, as well as the misconceptions surrounding the safety of cooking pork.
Get ready to learn some fascinating facts about your favorite breakfast food and meat!
Why Is Bacon Pink And Pork White?
Bacon and pork come from the same animal, so why do they look so different? The answer lies in the curing process.
When pork is cured for bacon, it is treated with a mixture of salt, sugar, and nitrates or nitrites. These ingredients help to preserve the meat and give it that distinct bacon flavor. During the curing process, the meat turns from a pale, near-cream color to a bright pink.
The pink color of bacon comes from the nitrates or nitrites used in the curing process. These chemicals react with the myoglobin in the meat to form nitrosomyoglobin, which gives bacon its pink color.
On the other hand, fresh pork is typically white or light pink in color. This is because pork contains less myoglobin than beef or lamb, which are darker red meats. The color of pork can also vary depending on the breed of pig and how it was raised.
The Science Of Meat Color
Meat color is an important factor in the purchasing decisions of consumers. The color of meat is an indicator of quality, flavor, tenderness, wholesomeness, safety, and doneness. The core component of meat color is the pigment myoglobin, which is a heme-iron-containing protein found in muscle. Myoglobin serves to store oxygen brought to muscle through the blood supply for when it is needed. Some muscles will have more myoglobin than others, and locomotive muscles will have more myoglobin than support muscles.
Myoglobin is a pigment, so the more myoglobin present in a muscle, the darker the color of the meat will be. As animals increase in age, myoglobin loses its affinity to bind oxygen, making meat from older animals darker than meat from younger animals. Myoglobin contains a porphyrin ring that has iron at its center. Iron is the element where oxygen binds when it is transferred from hemoglobin in the living muscle. In the case of meat, oxygen binds to myoglobin through the process of oxygenation or “blooming,” resulting in the familiar bright cherry red beef color or the grayish pink pork color.
When there is no oxygen available, the compound is called deoxymyoglobin, and meat in this state will be light to dark purple in color depending on the species. Exposing meat to oxygen through the blooming process causes it to become the bright pink or red color consumers are accustomed to seeing in traditional polyvinyl chloride (P.V.C.)-wrapped packages in retail stores.
The transition from oxymyoglobin to deoxymyoglobin, which happens in vacuum-packaged products, is a much longer process. The oxygen has to be consumed by the muscle or otherwise removed for this transition to occur. When there are low partial pressures of oxygen present – too much for the formation of deoxymyoglobin and too little for oxymyoglobin to form – the iron in myoglobin will oxidize and the brown pigment metmyoglobin will appear.
The type of muscle, its postmortem age, and even quality grade may impact the transition from purple to red with a stop through brown. If steaks are frozen when they are in this brown stage, they are likely to remain there making them less appealing to most customers.
Once meat is obtained from carcasses, meat color can be influenced by many factors that are interrelated and can lead to important visual changes and ultimately influence consumers’ perception of quality and freshness. In this regard, the main factors influencing the color of fresh meat are temperature, packaging conditions, and lipid oxidation during aging and exposure to consumers. Temperature is an important factor by influencing the stability of myoglobin structure. Low temperatures can help preserve myoglobin’s red color by slowing down oxidation reactions that cause metmyoglobin formation.
What Makes Bacon Pink?
The distinctive pink color of bacon is produced by the chemical reactions that occur during the curing process. Sodium nitrite is infused into the fresh meat, which is quickly converted to nitric oxide (NO). Nitric oxide then binds to myoglobin and changes the color of the meat to a bright red known as nitroslymyoglobin. When the meat is subsequently heated, the NO-myoglobin complex undergoes further chemical reactions and changes myoglobin to a compound known as nitrosylhemochrome. This produces the characteristic pink color of cured meats like bacon.
In addition to providing color, nitric oxide also has an important role in preventing food poisoning. It inhibits the outgrowth of Clostridium botulinum spores and prevents the production of the very potent botulinum neurotoxin. However, the use of nitrates and nitrites in processed meats like bacon has been linked to an increased risk of cancer and other health issues. Uncured bacon, which does not contain added nitrates or nitrites, is becoming more popular as a healthier alternative.
The Truth About Cooking Pork
Many people are still under the impression that pork should be cooked until it is well-done in order to avoid trichinosis, a food-borne illness caused by a parasite found in undercooked pork. However, this is no longer the case. The USDA has recently revised their cooking guidelines for whole muscle meats, including pork, recommending that it be cooked to an internal temperature of 145°F and then allowed to rest for three minutes before eating.
This new guideline is based on the fact that trichinella spiralis, the parasite responsible for trichinosis, has been virtually eliminated from the US pig population. In addition, the parasite is killed when cooked to 137°F, well below the recommended cooking temperature for pork.
Overcooking pork can result in dry and tough meat, which is why it is important to use a meat thermometer to ensure that it reaches the recommended internal temperature of 145°F. Ground pork should be cooked to 160°F to ensure that any bacteria present are destroyed.
It is also worth noting that pork has become leaner in recent years and contains less marbling than it used to. This means that overcooking can result in dry and tough meat. By following the new cooking guidelines, you can enjoy juicier and more flavorful pork while still ensuring that it is safe to eat.
The Evolution Of Pork Safety Guidelines
Over the years, the safety guidelines for cooking pork have evolved. In the past, there was a concern for Trichinella spiralis, a parasite that can be found in pork. To prevent the risk of infection, pork was typically overcooked and white in color. Cookbooks instructed to cook pork until it reached an internal temperature of 160F (71C), which is considered medium doneness.
However, under FDA guidelines, pork can actually be cooked to a lower temperature of 145F (63C) for 3 minutes or 150F (66C) for 1 minute. Cooking pork at a lower temperature not only improves the moisture and flavor of the product, but it also ensures safety. The dry, mild flavor that often accompanies pork is due to cooking beyond 160F (71C).
It’s important to note that the color of cooked pork is not always an accurate indicator of its safety. Many cookbooks claim that the juices have to run clear to prevent food-borne illness, but this is not always the case. Pork chops can remain pink even after reaching the optimal time and temperature combination for safety. The color of pork depends on which time and temperature combination identified by the FDA Food Code is used. Chops that are pale, soft and exudative (PSE) or dark, firm and dry (DFD) will also have different cooked color.
To ensure that pork is cooked safely and to the desired level of doneness, it’s recommended to use a meat thermometer rather than judging meat doneness by appearance alone. This is especially important when cooking ground pork patties, which may exhibit premature browning that can be a concern from a food safety standpoint.
The Importance Of Properly Cooking Pork
Properly cooking pork is crucial for both safety and flavor. Pork can be a source of harmful bacteria, such as Trichinella spiralis, which can cause food poisoning if not cooked thoroughly. In the past, it was recommended to cook pork until it was well done, which often resulted in dry and tough meat. However, the USDA has revised their cooking guidelines for whole muscle cuts of pork, recommending that it be cooked to an internal temperature of 145°F and then allowed to rest for three minutes before eating.
This rest period is important because it allows the temperature to remain stable or even continue to rise, which can help kill off any harmful bacteria that may be present. Additionally, letting the meat rest after cooking allows the juices to redistribute back into the fibers of the meat, resulting in a more flavorful and tender product.
It’s important to note that these revised cooking guidelines only apply to whole muscle cuts of pork. Ground pork should still be cooked to an internal temperature of 160°F, and all poultry products should be cooked to 165°F. When cooking any type of meat, it’s important to use a food thermometer to ensure that it has reached the appropriate temperature for safe consumption.
In addition to safety concerns, properly cooking pork can also enhance its nutritional value. Pork is a rich source of high-quality protein, as well as vitamins and minerals like iron and zinc. Eating lean, fully-cooked pork in moderation can provide numerous health benefits, including helping to maintain muscle mass and improve muscle performance.
Other Factors That Affect Meat Color
Aside from the curing process and the amount of myoglobin in the meat, there are other factors that can affect the color of meat. These factors include antemortem factors such as the species, stress, sex, and age of the animal. Additionally, postmortem pH rate of decline and ultimate pH of the meat can also affect its color intensity.
Seasonal effects can also have an impact on meat color. Differences in animal behavior during mating versus non-mating season, as well as the quality of pasture and susceptibility to physiological stress, can lead to variations in meat color. However, seasonal effects may be confounded by other factors such as geographical location and species or breed of the animals.
Meat processing also plays a role in determining its color. The pH level, redox state of myoglobin, amino acid sequence of myoglobin, and presence of antioxidants and prooxidants can all affect the thermal stability of myoglobin and thus influence the cooked color of meat.
