It can be surprising to see black dots on puff pastry, but in most cases they are completely harmless. Before discarding the dough, take a moment to examine it carefully. Many specks are simply a normal result of ingredients reacting to air, cold storage, or heat during baking. First, check for signs of mold.
True mold usually appears fuzzy, raised, or moist, often in shades of blue, green, or white. It may also produce a sour or musty smell. If you notice these characteristics, it is safest to discard the pastry. However, flat, dry, uniform dots that look like tiny freckles are typically not mold. These marks do not spread, smear, or feel soft. There are several common reasons for harmless black specks.

One is natural bran particles, especially in less refined or stone-ground flour. Another is caramelized milk solids from butter, which can darken during baking and even add flavor. Oxidation can also cause slight discoloration if the dough has been stored for a long time or repeatedly thawed. In some cases, residue on baking sheets can transfer onto the pastry, which is easily prevented by using clean pans or parchment paper.
To stay safe, always check the smell, texture, and color. Keep dough tightly sealed in the freezer and avoid unnecessary thawing. When in doubt, prioritize food safety. If the pastry looks and smells normal, you can confidently continue with your recipe and enjoy baking without concern.