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My Opinion on Pet Food Adulteration

cedardell

Well-known member
Chinese feed companies deliberatly added the melanine to the feed to defraud the buyers of the feed into thinking it was higher in protein than it was. Evidently melinine has the same molecular structure as some protiens even though it does not function. So actually when you subtract the nonfunctioning protein from the label content you are left with just a little over 1/2 the label rate. So even if they are forgiven trying to poison the pets, they cannot be foregiven trying to starve them by defrauding the consumer with a false label. There needs to be Justice in this case and the perpitrators need to be punished. Since they are in China, how do we do that? We can't just hike over there and cain them. We can't sue them, they'd just laugh at us and our stupid capitilist ways. So where is the Justice in this World trade business? Or was the "World Trade Concept "desighned to circumvent Justice.
 

Mike

Well-known member
Evidently melinine has the same molecular structure as some protiens even though it does not function.

My chemist buddy explained to me that melamine is an inexpensive made polymer (plastic) that has a high nitrogen content.

"2.1 ANALYTICAL METHODS FOR PROTEINS IN FOODS
2.1.1 Current status

For many years, the protein content of foods has been determined on the basis of total nitrogen content, while the Kjeldahl (or similar) method has been almost universally applied to determine nitrogen content (AOAC, 2000). Nitrogen content is then multiplied by a factor to arrive at protein content. This approach is based on two assumptions: that dietary carbohydrates and fats do not contain nitrogen, and that nearly all of the nitrogen in the diet is present as amino acids in proteins. On the basis of early determinations, the average nitrogen (N) content of proteins was found to be about 16 percent, which led to use of the calculation N x 6.25 (1/0.16 = 6.25) to convert nitrogen content into protein content.

This use of a single factor, 6.25, is confounded by two considerations. First, not all nitrogen in foods is found in proteins: it is also contained in variable quantities of other compounds, such as free amino acids, nucleotides, creatine and choline, where it is referred to as non-protein nitrogen (NPN). Only a small part of NPN is available for the synthesis of (non-essential) amino acids. Second, the nitrogen content of specific amino acids (as a percentage of weight) varies according to the molecular weight of the amino acid and the number of nitrogen atoms it contains (from one to four, depending on the amino acid in question). Based on these facts, and the different amino acid compositions of various proteins, the nitrogen content of proteins actually varies from about 13 to 19 percent. This would equate to nitrogen conversion factors ranging from 5.26 (1/0.19) to 7.69 (1/0.13).

In response to these considerations, Jones (1941) suggested that N x 6.25 be abandoned and replaced by N x a factor specific for the food in question. These specific factors, now referred to as “Jones factors”, have been widely adopted. Jones factors for the most commonly eaten foods range from 5.18 (nuts, seeds) to 6.38 (milk). It turns out, however, that most foods with a high proportion of nitrogen as NPN contain relatively small amounts of total N (Merrill and Watt, 1955; and 1973).[4] As a result, the range of Jones factors for major sources of protein in the diet is narrower. Jones factors for animal proteins such as meat, milk and eggs are between 6.25 and 6.38; those for the vegetable proteins that supply substantial quantities of protein in cereal-/legume-based diets are generally in the range of 5.7 to 6.25. Use of the high-end factor (6.38) relative to 6.25 increases apparent protein content by 2 percent. Use of a specific factor of 5.7 (Sosulski and Imafidon, 1990) rather than the general factor of 6.25 decreases the apparent protein content by 9 percent for specific foods. In practical terms, the range of differences between the general factor of 6.25 and Jones factors is narrower than it at first appears (about 1 percent), especially for mixed diets. Table 2.1 gives examples of the Jones factors for a selection of foods.

Because proteins are made up of chains of amino acids joined by peptide bonds, they can be hydrolysed to their component amino acids, which can then be measured by ion-exchange, gas-liquid or high-performance liquid chromatography. The sum of the amino acids then represents the protein content (by weight) of the food. This is sometimes referred to as a “true protein”. The advantage of this approach is that it requires no assumptions about, or knowledge of, either the NPN content of the food or the relative proportions of specific amino acids - thus removing the two problems with the use of total N x a conversion factor. Its disadvantage is that it requires more sophisticated equipment than the Kjeldahl method, and thus may be beyond the capacity of many laboratories, especially those that carry out only intermittent analyses. In addition, experience with the method is important; some amino acids (e.g. the sulphur-containing amino acids and tryptophan) are more difficult to determine than others. Despite the complexities of amino acid analysis, in general there has been reasonably good agreement among laboratories and methods (King-Brink and Sebranek, 1993)."
 
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