Technically, dried orange peel and orange zest are different ingredients. Zest includes only the outermost portion of the rind to achieve a brighter and more aromatic flavor. Dried orange peel includes both the outer peel and the inner pith, which results in a slightly more bitter flavor. Still, you can substitute dried orange peel for orange zest in a pinch. However, it’s important to remember that the dried version is much more potent. Use only one-third of a teaspoon for every teaspoon of fresh orange zest.