Hotness – SHU (Scoville)

Well, your bad – you won’t. It’s not like the Scoville Scale (if you’re not up to, scroll down to tl;dr) is total sham, but it has serious limitations. It measures the content of capsaicin in dry mass – and our sauces are, surprise surprise, wet. We produce hot sauces from fresh peppers, which can vary in hotness even on a single plant. And because we make craft hot sauces (which means that we mix them in pots and pour into bottles ourselves), each batch has its unique character and pungency. Each of our sauces is filled with peppers as much as possible – in most of them the content of peppers reaches 30, and even 35 percent. So drop the puny sauces with trace amounts of peppers.

Another issue is that measuring capsaicin content costs money and some manufacturers prefer to dream up (i.e., make rough estimates of) exorbitant values that can’t be verified anyway. It doesn’t really amuse us, so we created our own scale.

SHU, meaning Scoville Hotness Unit, is a measure of pungency on a scale created in 1912 by the American pharmacist Wilbur Scoville. Scoville was also one of the first to recommend milk as an antidote to the burning sensation caused by eating spicy stuff. The scale was initially based on an organoleptic test – which means tasting.

A strictly defined amount of dried peppers was dissolved in alcohol in order to extract capsainocids, and later gradually diluted in sugar water. Five testers were tasting increasingly diluted extracts until at least three of them deemed the hotness to be imperceptible. The scale reflected the dilution level needed to reach this point – e.g., in case of Habanero peppers they had to be diluted between 100 000 and 350 000 for the hotness to become imperceptible.

This method had its obvious limitations – it was very time-consuming, the procedure was tedious, and the tasters’ individual sensitivity to heat, fatigue and subjectivity. All this resulted in low precision, which caused it to be replaced by more modern techniques.

The scale and unit retained their names, but currently it measures the concentration of capsaicin using chromatography (and more specifically HPLC, which stands for high-performance liquid chromatography). It consists in drying and grinding the tested substance to powder. Then, the chemical compounds responsible for heat are extracted and analyzed in a HPLC apparatus. It enables objective, precise and quick measurements.

Nonetheless, the usefulness of this method in choosing hot peppers and sauces for consumption is quite limited. This test gives results pertaining to dry mass units. Because of that, comparisons between products with varying water contents can be misleading – fresh peppers contain much more water than dried ones, and hot sauces contain other liquids, such as vinegar, tomato sauce, etc. It is easy to determine the hotness level of capsaicin extracts – but nobody in their right mind eats those, right? (Well, we know some and we like them and respect them, but we’re not sure if we understand them.)