Why does freshly ground pepper have so much more flavor than pepper that has been ground ahead of time?
In: Chemistry
Aromatic things like spices and coffee are constantly spewing out little bits of their volatile smell-good chemicals into the air. Any time you grind something up you’re exponentially increasing the surface area of that thing. This allows those volatile compounds MUCH easier access to air, causing them to escape at a faster rate. Pre-ground spices will lose a bunch of these compounds at a much faster rate than if they were kept whole and then ground shortly before use. This is also why speciality coffee roasters reccommend you buy whole-bean coffee and grind it at home; you’re more likely to be consuming a fresher tasting product that still contains a good amount of those tasty volatile aromatics if the product spends the majority of its shelf time whole and unground.
Whole peppercorn and coffee beans can still go stale and lose much of their aroma, it just takes a much longer time since in this form a comparatively small amount of surface area is exposed to the air.
There is also most likely some oxidation of certain aromatic oils, just like when the fat in a nut goes “rancid” after being left out too long. However I don’t know much about the specifics of these processes and it is more than likely that the degradation in flavor is primarily caused by the escape of volatile compounds. Oxidation is usually associated with tasting “off” or gross flavors, while spices usually just lose their aroma and get more bland over time.
Grinding it releases the oils inside. the longer it sits around after being ground, the more oils evaporate and the less taste it has.
The flavour of pepper comes from an oil. The oil is volatile and evaporates over time. Grinding it makes it easier for the oil to evaporate.
Latest Answers