Hehe,
no ..... not iron detection with an 'uber magnet'. The magnet would be for Nuclear Magnetic Resonance (Spectroscopy) Aussie beat me to it while typing this up.
There is a whole gamut of measuring methods for quantitative analysis, all with their pro's and negatives which may lead to a multiple testing approach via several testing methods combined to get a more precise overall picture of the true level of active compounds in the tested samples. Ed was speaking in the article about the the initial HPLC extractions then being submitted to the 'magnet thingie' (NMR) for further precision testing/results. HPLC (High Performance Liquid Chromatography) is the preferred 'set standard (?)' for analysis currently, but can't say if its combination with NMR is the actual true standard of measurement for measuring/finalizing an official heat rating for world record status (Guinness standards that is). The procedure for officially measuring Scoville units is not public information - that I am aware of -(set by the American Spice Trade Association (ASTA). They state that HPLC
is the standard (as read below) but personally I'm guessing NMR testing is/
should be part of it. Testing via HPLC does not measure everything- which is what I think you would want, especially for a world record!
Quick run down-
Capsaicin and dihydrocapsaicin being the two most common/dominant alkaloidal compounds in peppers, this is primarily what the HPLC measures with its set standards to compare to. This does not account for the many other known compounds that may/do contribute to heat (as well as flavor, etc..) such as :
nordihydrocapsaicin (7 percent), homocapsaicin (1 percent), and homo-dihydrocapsaicin (1 percent).......
This is where the NMR testing would come into play with the detection and analyzing of the lesser compounds that Ed may be factoring in with the HPLC results for the two dominant compounds (capsaicin & dihydrocapsaicin) for a more total picture of the pungency of the said tested peppers. Who knows?!?!?...my head hurts now..leave this to the techies. I just like growing, looking at, and tasting the pretty peppers. Cheers!
Here's the above mentioned addendum:
The analysis for the heat bearing components of red peppers has been with us since the early 1900’s. The analytical methodology for heat determination has been one of constant evolution with a great deal of activity in the past ten years. American Spice Trade Association (ASTA) Method 21.0, the old Scoville Heat Test used by industry for many years, had a large variability due to:
· Lack of reference standard
· Lack of statistical validity
· Poor test reproducibility
· Ethanol bite in sample
· Increase taste threshold
· Rapid taste fatigue
· Build up of heat
Moreover, ASTA Test Method 21.1 was developed by a single laboratory and required the use of some chemicals that are no longer deemed safe by the Federal Government. Therefore, in December 1998, ASTA determined that methods 21.0 and 21.1, as methods to determine capsicum, were made obsolete.
ASTA Method 21.3, Pungency Of Capsicums And Their Oleoresins (HPLC Method) was adopted December 1998 and remains as the only official method recognized for the analysis of capsicum heat. It is a collaborative method developed by the ASTA in conjunction with the American Organization of Analytical Chemists (AOAC). The ASTA Executive Committee of the Technical Group has determined that methods 21.0 and 21.1 are no longer valid test, and that Method 21.3 is to be the only official method used for the analysis of capsicum heat.
Merle I. Eiss
Technical Director, ASTA