Brown spots on potato chips? (Plus, lasers!)

What you see: Brown or black areas on your potato chips.
What it is: Minor imperfections that don’t impact the safety of the chip—they could be bruises or the result of excess potato sugars darkening during frying.
Eat or toss: Eat!

Is it OK to eat potato chips with brown spots? Here’s the story.

Everyone has their own way of dealing with stress. Some might go for a run. Others might take a moment to meditate. Still others might go in search of a snack.

Then, there’s the potato. When faced with stress, a potato turns its starches into sugars.

Physical damage AND sugar conversion lead to dark spots

Potato stressors might include rough handling or the indignity of lying at the bottom of the potato heap. Such impacts can lead to bruising on the potato’s surface or just beneath it. Storage at too-cold temperatures and infections also insult a potato’s sensitivities. In all of these scenarios, off colors can appear in the raw potato’s flesh and remain as unsightly brown spots in your potato chips.

Everything we’ve described above is a physical change that you can see. But those stressful events, along with other stressful conditions can causes the potato to turn its starches into sugars. This is a sneakier form of discoloration in potato chips and fries, which can’t always be predicted merely by looking at a raw potato. Stressed potatoes breathe at a faster rate, which, along with other factors, causes the potato to turn more of its starches into quick-energy sugars. And that sugar, while invisible in a raw potato, turns brown when it’s fried.

No safety concerns with brown areas on potato chips

Don’t worry about eating potato chips with brown areas. You might notice a softer texture, but, even with the excess sugar, any flavor change will probably be slight or undetectable.

“I don’t necessarily pick up on the sugar/sweetness,” Nora Olsen, professor and extension potato specialist at the University of Idaho, wrote in an email. “Maybe I am eating them too fast!”

We promised lasers! Here are the lasers!

Of course, brown areas are unsightly and chip manufacturers try to minimize them. In processing plants, Olsen told me, electronic “eyes” scan for potatoes with brown spots and specialized lasers cut them out.

Holy potato lasers, Batman!