Talking about melamine

Abstract: Heterocyclic ring is an important organic chemical raw materials. Melamine industry by double cyanide (acyl) amine and ammonia at a high temperature direct reaction or by the urea prepared under high temperature and pressure, which low-cost, more adopted. commonly used in food industry, and was designated as a national standard Kjeldahl method. Kjeldahl method is actually not the protein content measured, but estimated by measuring nitrogen content to protein content, as the main component in food Only proteins containing nitrogen, other major components (carbohydrate, fat is not nitrogen, so Kjeldahl method is a very accurate method for the determination of protein content. If there are other compounds in the samples containing nitrogen, Kjeldahl method is not accurate.

"Sanlu infant milk powder incident" occurred, that is, lawless elements in the material with water to add weight to obtain illegal benefits.

Because melamine slightly toxic, we do not have to talk about "Tiger" colors.

Keywords: Melamine; principle; determination; Health and safety

Melamine, a chemical we are unfamiliar terminology, in the Sanlu infant formula incident, a time of concern to the media and people
Focus, to become the talk of the streets. Melamine in the end what matter? How there will be a necessity in our daily lives - dairy products as well?
Melamine formula C3H6N6. Also known as melamine, 2, 4, 6 - triamino -1,3,5 - triazine. White monoclinic prisms, odorless, slightly soluble in water and hot alcohol, drugs, melamine was weak base nature (pKa = 8, the reaction with a variety of acid melamine salt. The case of strong acid or alkali solution of salt hydrolysis, amino hydroxy gradually replaced Mr. diamide into cyanuric acid, cyanuric acid hydrolysis and further a amide, the last generation of cyanuric acid. Heterocyclic ring is an important organic chemical raw materials. melamine industry by double cyanide (acyl) amine and ammonia at a high temperature direct reaction or by the urea prepared under high temperature and pressure, which low cost, more adopted.

Our daily consumption of fresh milk and its protein content according to national testing standards should be 100 ml of> = 2.9 grams. Actually the protein content of raw milk is generally more than 3%, it is generally able to meet the national standards, to raw milk to prevent in dilute water, the acquisition of fresh milk protein content was detected. commonly used in food industry, and was designated as a national standard Kjeldahl method. principle is simple: proteins contain nitrogen, samples were treated with acid so that protein release nitrogen in the measured nitrogen content, protein content can be calculated. such as milk protein nitrogen rate of about 16%, according to national standards, to measure the nitrogen content multiplied by 6.38, is the protein content . So Kjeldahl method is not actually measured the protein content, but by measuring the nitrogen content to calculate protein content, because the major components of food proteins contain only nitrogen and other major components (carbohydrates, fats do not contain nitrogen, So Kjeldahl method is a very accurate method of determination of protein content. If there are other compounds in the samples containing nitrogen, Kjeldahl method is not accurate.

Links to Research Papers Download http://www.hi138.com "Sanlu infant milk powder incident" occurred, that is, lawless elements in the material with water to add weight to obtain illegal benefits. Milk mixed with water will cause decreased protein content in raw milk, to cover up their illegal conduct, inflated the amount of milk protein detection, human criminals adding melamine in raw milk. so, fool Kjeldahl method to obtain a false high protein content. because of melamine nitrogen content as high as 66.6% (the higher the nitrogen content means that more protein can impersonate a white, odorless, low price, is the ideal protein posing thing. melamine in the production process, there will be waste, waste also contains 70% melamine. counterfeiters used to impersonate residue protein is melamine, and some "Biotechnology company" online marketing "protein powder", in fact, melamine residue.

At present, because melamine is considered slightly toxic, rat oral median lethal dose greater than 3 g / kg body weight. However, according to an experiment reported in 1945: the large doses of melamine fed to rats, rabbits and dogs was not observed after obvious toxicity. but melamine can cause long-term animal reproductive, urinary system damage, bladder, kidney stones and may further induce bladder cancer. So Melamine is a prohibited pet food and animal feed chemicals. its toxicity, we can not take a test body, because even if the person suffering from kidney stones had been stolen added melamine to take food, it is difficult to determine melamine is the culprit, unless the patient is a single food source, such as eating only milk formula baby - the baby really did not expect to do some dare cross test proved that it can eat the dead! As of Sept. 15, national Health agencies in admissions, screening food Sanlu infant formula in infants 6244, 1327 children with clinical diagnosis, and another three have died.

Because melamine slightly toxic, we do not have to talk about "Tiger" colors. This is because melamine is not only widely used in plastics, coatings, adhesives and other chemicals used in pesticides and fertilizers is also the raw material and metabolites, but also the raw material for food packaging materials . As we adopt melamine - formaldehyde resin production of food utensils and food contact in the inevitable migration from small amounts of melamine. the melamine in the environment, these factors can result in milk and dairy products may contain traces of melamine. So October 7 Ministry of Health jointly issued a notice five departments to determine the milk and dairy products melamine limit value, that infant formula milk powder melamine limit value of 1 mg / kg of liquid milk (including raw milk, milk powder the other limit of melamine in formula milk powder is 2,5 mg / kg groups of experts, based on daily tolerable intake of melamine, after a precise calculation can be concluded that limited value can guarantee the Health and safety of consumers. Current methods of the provisions of melamine into three, namely, high performance liquid chromatography (HPLC, gas chromatography - mass spectrometry (GC-MS and liquid chromatography - mass spectrometry / mass spectrometry (LC-MS/MS), the quantitative limit (accuracy was 2 mg / kg, 0.05 mg / kg and 0.01 mg / kg. as long as the testing of melamine in samples of the real content of the above detection limit of quantification, detection methods can be accurately detected, the purpose is to prohibit people adding melamine. Therefore, the temporary administrative limits of melamine will maximize the protection of human Health.

Links to Research Papers Download http://www.hi138.com