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Meat Pigments Most consumers look at meat color to judge freshness– but let’s look at the chemistry behind meat color.

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Presentation on theme: "Meat Pigments Most consumers look at meat color to judge freshness– but let’s look at the chemistry behind meat color."— Presentation transcript:

1 Meat Pigments Most consumers look at meat color to judge freshness– but let’s look at the chemistry behind meat color

2 Myoglobin One pigment– myoglobin – stores oxygen in muscles (meat!) Right after slaughter, the muscles are a deep reddish purple color. This would accurately be when the meat is freshest

3 Oxymyoglobin When air contacts the meat, oxygen binds to the myoglobin, turning it to oxymyoglobin which is bright red (which makes us think that older meat looks more fresh)

4 Metmyoglobin The last stage is this. Myoglobin and oxymyoglobin are unstable pigments. This means they lose electrons easily which causes them to a change to a brownish color. What’s weird is that you can get these colors to change back and forth by adding oxygen… But when meat is cooked it turns brown and nothing can change it back to red…. Or can it???

5 Better living through chemistry? Yippee! Now cooked meat can be red! Well, kind of pink. Think HAM and HOT DOGS and SPAM!! Meat that can never grow old! Youthful meat!

6 Thanks, sodium nitrate! Your task is to draw a series of color pictures or make up a color cartoon which shows your understanding of the natural changes which occur in muscle (meat) and why we use chemicals to preserve the meat’s color.

7 Chemical reaction or Drama? Sodium Nitrate stabilizes the red color of meat. Unfortunately, it also combines chemically with acid in the consumer’s stomach to form a more dangerous compound

8 Nitrite and Nitrate http://www.sweetpoison.com/food-additives-to-avoid.html “Sodium nitrite and sodium nitrate are two closely related chemicals used for centuries to preserve meat. While nitrate itself is harmless, it is readily converted to nitrite. When nitrite combines with compounds called secondary amines, it forms nitrosamines, extremely powerful cancer-causing chemicals. The chemical reaction occurs most readily at the high temperatures of frying. Nitrite has long been suspected as being a cause of stomach cancer. Look for nitrite-free processed meats -- some of which are frozen, refrigeration reduces the need for nitrites -- at some health food and grocery stores. But regardless of the presence of nitrite or nitrosamines, the high-fat, high-sodium content of most processed meats should be enough to discourage you from choosing them. And don't cook with bacon drippings.”

9 by Mike Adams, the Health Ranger Editor of NaturalNews.com http://www.naturalnews.com/007024.html http://www.naturalnews.com/007024.html “Processed meat consumption results in 67% increase in pancreatic cancer risk, says new research” Consuming processed meats increases the risk of pancreatic cancer, says new research conducted at the University of Hawaii that followed nearly 200,000 men and women for seven years.

10 As of June 2004, the American Medical Association concludes that: "Data are irrefutable that when ingested in high concentrations nitrites can cause methemoglobinemia. Additionally, certain populations such as infants may be particularly vulnerable. However, the human body can tolerate fairly high levels of methemoglobin before toxemia sets in. Thus, there have been no reports of methemoglobinemia caused by nitrites added intentionally to food, although disease caused by contamination of water and food by sodium nitrite has been reported. USDA regulations do not permit nitrites and nitrates in baby, junior, or toddler foods. The scientific evidence is clear that NOCs have carcinogenic effects in animal models. Thus, it must be assumed that at the right concentrations, NOCs are likely to be carcinogenic in humans as well. The primary source of NOCs in the human diet is the nitrosation of secondary amines and amides by nitrites present in food. However, epidemiological studies cannot confirm the link between the presence of nitrites (or nitrates) in food and the formation of NOCs and the causation of human cancer. In fact, studies that suggest a link between nitrites in food and cancer have largely been disputed due to these studies’ inability to exclude confounding factors, such as recall bias. Regardless, the use of nitrites in the preparation and preservation of meats and poultry has been substantially reduced from the time when these studies were first performed. Additionally, the use of erythorbate and/or ascorbate with nitrites has been shown to inhibit the formation of NOCs. Accordingly, given the current FDA and USDA regulations on the use of nitrites, the risk of developing cancer as a result of consumption of nitrites-containing foods is negligible. (from Wikipedia, tagged for suspected bias) methemoglobinemiaNOCs

11 http://www.cspinet.org/reports/chemcuisin e.htm


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