54 ppm or 80 ppm – What do the numbers really tell us?

Have you ever wondered what's behind the ppm figures on the labels of your favorite whiskies? Why does one bottle state 54 ppm while another advertises 80 ppm, even though we use the same peated malt from the Scottish Highlands? The answer lies in the method used to measure phenols in the malt.

The Colorimetric Method: Simple but Inaccurate

Previously, our supplier, Glen Esk Maltings, used a colorimetric method that was inaccurate and didn't capture all phenols, as some don't react to the color reagent. You can imagine it like a low-resolution telescope: you see fewer stars in the night sky than are actually there. This resulted in values like 54 ppm.

The HPLC Method: More Precise Thanks to Modern Technology

Today, a more precise method is used – the HPLC method (High Performance Liquid Chromatography). This method detects a wider range of phenols, much like a powerful telescope reveals more stars. Thanks to this method, we now measure 80 ppm.

What Do the ppm Figures Really Mean?

It's important to know: in both cases, the amount of phenols remains the same. The difference in ppm figures is solely due to the different measurement methods. Ultimately, however, these values say little about the taste of the whisky, as they only refer to the malt. How smoky or peaty the whisky ultimately tastes depends primarily on distillation and maturation.

Further details on the topic of PPM analysis can be found in the St. Kilian Whisky ABC.