-This is why nitrite added, MB gets converted to Mb(FE+2) NO which gives a pinkish reddish color. -Issue of nitrite has been a concern…. (nitrate gets converted into nitrites) -it gets converted to nitrosamines, they are known animal carcinogens
-ppl thought by taking this we will get cancer causing chemicals…studies have shown no reason to worry -most of nitrites we take in come from >90% natural sources. -cabbages/vegetables are high in nitrites.
-packaged hot dogs contain Vitamin C alongside with Nitrite. Vitamin C prevents conversion of nitrites to nitrosamines. -hot dogs will not be safe without nitrites, got to keep them refrigerated so toxins don’t develop and they will turn brown Nitrates are added to foods such as sausages and ham for three reasons: (1) to act as a preservative, (2) to improve the color of the product (3) to improve the taste of the product Bacon: -some say not preserved but some say no nitrates or nitrites added. except those naturally occurring in celery juice. (celery juice is rich in nitrates; this means that nitrates not added per say it is already present in the celery juice). Video 10 Notes: Mashed Potatoes: -made from "Real" potatoes -some ingredients are anti- oxidants -oxygen will react with food and cause problems -browning of fruits and vegetables -oxidation of fats causes rancidity. -antioxidants prevent these TWO events. Browning of Fruits and Vegetables: -after leaving in open, part of apple is brown and some is still clear. -the metal in the knife promotes the oxidation of some of the chemicals present in apple -you want something that will trap the metal to prevent this…. -chemical that will prevent this is citric acid (it traps the metal ions that will normally react with the food and cause the food to turn brown) -what you want is to tie up these metal ions, it acts as a chelating agent/ a sequestrate (to remove) Real Mayo: -EDTA (calcium disodium) and if we look at this structure, it is effective, it ties up metals from different directions. Sodium Sulfite: -Sodium Sulfite is Na2SO3. It acts as an antioxidant as well. Used as additive and to prevent food from going brown. Some people are allergic to sulfites…it has caused 20 deaths in the USA in the 1970's (add large amount to potato salads so doesn't brown…not used in salad bars anymore) -Sometimes used in grapes, keeps crunchiness in grapes.
-Always used in pre-cut french fries from fries from browning. -Also used in wine, to prevent wine from going bad. -One person died from it, prepared raisin bread and added dried raisins and those are preserved from sulfite.
BHT/BHA: -prevent oxidation of fats (rancidity) -makes food fresh -traps free radicals -free radicals are reactive species that promote oxidation of fats -BHT/BHA prevents this from occurring -free radicals will pick the Hydrogen of BHT and leave behind another radical on the BHT but this one was is much more stable b/c part of a bulky group. It won't attack other chemicals and oxidation will slow down…no free radical chain reaction.
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- Spring '11