What Is That White Stuff On Grapes (And Is It Safe To Eat)?

There's nothing quite as satisfying as the refreshingly crisp, sweet, yet tart bite of a perfectly ripe grape. However, people don't talk about sour grapes for no reason — sometimes buying, storing, and eating grapes feels like a game of Russian roulette. Luckily, we're here to alleviate at least one of your grape-related concerns. That suspicious white powdery stuff on your grapes is most likely completely normal and safe to eat. In fact, it's probably a positive thing.

If you notice a thin white or bluish film on your grapes, odds are it's a natural plant residue called a bloom. This waxy substance often appears on the surface of plants such as cabbage, plums, apples, and grapes, and you can rest assured that it's totally safe to consume. The bloom is produced by the grapes themselves, and it serves an important purpose — it protects your precious fruit from drying out and decaying. The bloom on your grapes is mainly composed of a compound called oleanolic acid, which may have antibiotic and anti-inflammatory properties.

So, bloom is great. It protects grapes from mold and keeps them nice and juicy, and it could even be quite healthy. But we'd all rather avoid the disgust and panic of accidentally eating mold, so how do you know that white stuff is blooming? One easy way to tell the difference is that bloom will cover all of the grapes in a consistent layer, while mold tends to be more spotty. Additionally, bloom is a powdery or waxy white or bluish substance, while moldy grapes usually appear obviously fuzzy, brown, or shriveled — none of which sounds very appetizing.

Even though bloom is safe to consume, it's always a good idea to wash your produce before eating. If there is any bloom, it will rinse off easily. As a semi-related side note, never rinse grapes until right before you are ready to eat them — washing not only removes the protective bloom, it introduces moisture (and mold loves moisture). In conclusion, that white stuff on your grapes is totally normal and safe to eat, and you might even want to seek it out the next time you're buying produce at the grocery store or farmers market.