Top Note

Flavor is usually described in three layers borrowed from perfume. Top notes are light, fast and hit first. Middle notes carry the recognizable character. Base notes are heavy and stay.

What makes a top note a top note is that it evaporates easily — and that is exactly what makes it fragile. The same low boiling point that gets it to your nose first also lets it escape during heating, soak into packaging, and react with the air in the headspace of a bottle.

What losing it looks like

• A citrus drink that smelled bright at the factory and reads flat and slightly waxy four months later.
• A baked product where the flavor is in the crumb but there is nothing when you open the pack.
• A powder that tastes right for the first scoop and progressively duller as the tub gets opened and closed.

The product has not gone off. It has lost its opening.

What helps

Encapsulate it. Add flavor after the hot step if your process allows. Keep oxygen out of the headspace. Use packaging with a real barrier. And run shelf life tests long enough and warm enough to catch the loss before your customers do.