You will clearly know what other elements are put in the oil and grease with wel

After understanding the fatty acid spectrum, you can understand what fake oil is mixed with!

In the past year, Jianming Customer Service Laboratory conducted fatty acid profiling analysis on approximately 500 oil samples and found that about 30% of the samples had abnormal fatty acid profiles. We can use this to determine that about 30% of oils are adulterated, resulting in changes in their fatty acid profile.

How to judge? Let's take a look:

Table 1 Fatty Acid Spectra of Normal Oil Samples

Note: U/S is the ratio of unsaturated fat to saturated fatty acid, and "-" is not detected; The data for lard, poultry oil, and soybean oil are the average values of the tested samples.

Table 1 lists the fatty acid profiles of five commonly used feed grade oils (including duck oil and chicken oil).

From Table 1, it can be seen that the main fatty acid components of different oils are composed of palmitic acid (C16), stearic acid (C18), oleic acid (C18:1), linoleic acid (C18:2), and linolenic acid (C18:3). However, the relative percentage content of each fatty acid is different, and the differences between different oils are mainly analyzed based on the relative percentage content of each fatty acid.

Compared to lard and poultry oil, the relative percentages of C16 and C18:1 are basically the same, about 24% and 39%, respectively. The difference is that the content of C18 in lard is higher than that in poultry oil, while the content of C18:2 and C18:3 is lower than that in poultry oil. In addition, the content of C20:2 in lard is generally greater than that of C20:4; On the contrary, poultry oil has a higher content of C20:4 than C20:2. And C20:2 and C20:4 are generally not detected in vegetable oil.

The main content of soybean oil is C18:2, which can reach 50%, followed by C18:3, which is about 6%. The highest content of cottonseed oil is C18:2, which is also more than 50%, but the content of C18:3 is relatively low, only 0.2%. In addition, the content of C16 in cottonseed oil (about 21%) is higher than that in soybean oil (about 11%).

Palm oil mainly has a relatively high content of C16 and C18:1, about 40%. However, the fatty acid spectrum of palm oil at different melting points is different. As the melting point increases, the relative percentage content of C16 and C18 gradually increases, while the relative percentage content of C18:1 and C18:2 gradually decreases.

Table 2 Fatty acid spectra of lard samples mixed with other fats and oils

Note: Red represents a higher value, green represents a lower value, and purple represents that it should not exist

Table 2 lists six samples of lard with abnormal fatty acid profiles. Based on their abnormal fatty acid composition and content, lard samples 1 and 2 may have been mixed with palm oil, 2 may have been mixed with high melting point palm oil, 3 may have been mixed with poultry oil, 4 may have been mixed with soybean oil, and the doping situation of 5 and 6 is relatively complex, and more than one type of oil may have been mixed.

By analogy, we determine that 39.37% of the lard samples measured by Jianming have doping, with 23.62% possibly mixed with palm oil, 3.94% mixed with poultry oil, and 0.79% mixed with soybean oil.

Fatty acid spectrum analysis of adulterated poultry oil samples

Table 3 Fatty Acid Spectra of Poultry Oil Samples Mixed with Other Oils

Note: Red represents a higher value, green represents a lower value, and purple represents that it should not exist

According to the fatty acid spectrum analysis, it is preliminarily judged that 53.11% of the poultry oil samples are adulterated, of which 32.77% may be mixed with palm oil, 6.78% with lard, 0.56% with soybean oil, and 2.26% with cottonseed oil.

Table 3 lists seven samples of poultry oil with abnormal fatty acid profiles. Based on their abnormal fatty acid composition and content, it is possible that palm oil may have been mixed in samples 1 and 2. The content of C16 indicates that the amount of palm oil mixed in the two parts of poultry oil is different. The proportion of palm oil in poultry oil 2 is greater than that in poultry oil 1. Compared with the fatty acid profile of palm oil, the content of palm oil in poultry oil 1 may be about 20% -30%, The content of palm oil in poultry oil 2 may be around 70% -80%. 3 may be mixed with lard, 4 may be mixed with soybean oil, 5 may be mixed with cottonseed oil, and 6 and 7 may be mixed with more than one kind of oil due to their complex doping.