What is pith and why must it be avoided when zesting?

Question

What exactly is the pith? Learn what this white layer is and the very important reason why you must avoid it at all costs when zesting.

Answer 1

Pith is the white, spongy layer between the peel and the fruit of citrus fruits. It should be avoided when zesting because it is bitter and lacks the aromatic oils found in the zest.

Detailed Explanation:

When zesting citrus fruits like lemons, limes, oranges, or grapefruits, you're aiming to extract the outermost layer of the peel, which contains the flavorful essential oils. This outer layer, called the zest, is where all the bright, citrusy aroma and taste reside. Beneath the zest lies the pith, a white, cottony substance that acts as a protective layer for the fruit.

The pith is composed of pectin and other compounds that contribute a distinctly bitter and unpleasant flavor. Unlike the zest, it doesn't contain the desirable aromatic oils. If you include pith in your zest, it will impart a bitter taste to your dish, overpowering the delicate citrus flavor you're trying to achieve. Therefore, careful technique is crucial to avoid grating or peeling too deeply and incorporating the pith.

Pro Tip:

Use a microplane zester for best results. Its fine blades allow you to remove only the zest without digging into the pith. Apply gentle pressure and stop as soon as you see the white pith appearing.