How to taste chocolate

Room temperature, around 20°C. Chocolate straight from the fridge is aromatically closed and will taste of very little. No strong smells nearby, and no coffee immediately beforehand.

A well-tempered bar has an even sheen and snaps cleanly. A dull surface, a soft bend or grey streaking indicates poor tempering or poor storage — before tasting anything, that already tells you something about how the bar was made and kept.

Break a piece and smell immediately; breaking releases aromatics. Most of what is perceived as flavour is retronasal aroma, so this step is not ceremonial.

Place a piece on the tongue and let it melt against the roof of the mouth for a minute or so. Aromatic compounds are released progressively as the cocoa butter melts, and the profile changes across that minute — front, middle and finish are genuinely different in good chocolate.

Bitterness is a taste on the tongue. Astringency is a tactile drying and puckering sensation. They are routinely conflated and they have different causes: bitterness is largely inherent to the bean and the percentage, while marked astringency generally indicates under-fermentation. A bar that dries the mouth is telling you about its post-harvest handling.

Sharp vinegary sourness usually means acid trapped by fast drying. Musty or cellar-like notes mean mould from slow drying or damp storage. Acrid, ashy bitterness means over-roasting. Chalkiness or grain means under-refining. A winey, slightly rotten fruit character means over-fermentation. Recognising these is more useful than any vocabulary of positive descriptors, because it tells a reader whether they dislike a bar or whether the bar is defective.

Work from lower percentage to higher and from milder to more intense. Rinse with water and, if palate fatigue sets in, plain bread. Beyond four or five bars discrimination falls off sharply regardless of technique.