NIR and PUFA content in animal feed

Lefrosinija's picture

Dear all,
I was planning to work on discrimination of feeds supplemented with various levels of n-3 fatty acids, using NIR. The sources od fatty acids would be different: lineseed oil, fish oil and synthetic PUFAs. I was wondering if it is possible, because the content of n-3 fatty acids is way below 1% in these feeds.
Best regards, 

td's picture

Hello Marijana,
It is always unwise to say that something cannot be done by NIR because someone will prove you wrong!
However, I think your proposal is unlikely to be reliable. Can I suggest you concentrate the supplement by doing a solvent extraction and then scanninng a sample of the extract on a filter paper (after evaporting the solvent).
Good luck and Best wishes,

ianm's picture

With several different sources of poly-unsaturated fatty acids, coupled with low concentrations, you will probably not be able to achieve r-squared values of much better than 0.7, so if that will satisfy your needs, yes it should be possible.

Posted by Ian Michael on behalf of Phil Williams

knnirs's picture

Hello Marijana,
I will be positive but I am not sure you can obtain adequate signal to noise.
I suggest measurement in transmittance in the 1100 to 1300 nm region on a finely
ground sample of a thickness that provides a maximum absorbance of 2.0 using 
an instrument with the best signal to noise in this region.