Little lines on jalapeño peppers

What you see: Little brown or white-ish lines or scars on your jalapeño peppers.
What it is: Basically, stretch marks. The pepper grew so fast its outer skin cracked and then healed, leaving brown or white lines behind. 
Eat or toss? Eat! The lines might look like blemishes to a U.S. consumer, but in some countries they’re viewed as a positive; they indicate a hotter pepper.

Jalapeños with lines are safe to eat

These are growth cracks, which you also see on bell peppers, tomatoes and other foods. Essentially, the pepper grew faster than its outer skin could keep up with so it cracked. The lines are also called corking, striations or corky striations.

When peppers are in growth mode, their cells are flexible and easily expand, as Chris Gunter, a professor at North Carolina State University, explained in our post about growth cracks on bell peppers. But if environmental conditions like dry weather convince the pepper that it’s not a good time to grow, those same cells stiffen up. At that point, if there’s, say, a sudden influx of water from heavy rain, the pepper will grow quickly, but those less elastic cells won’t have enough give. Thus, cracks. 

If you see dry lines like those on the jalapeño pictured at the top of this post, you can be confident the splits healed just fine. If the pepper were sporting open, wet wounds, that would indicate something was amiss and that microbial infection was possible. You’d want to generously cut off the damaged area or skip a pepper with open wounds altogether. 

Lined jalapeños are said to be hotter

According to the University of California’s Postharvest Research and Extension Center, U.S. consumers don’t like to see lines on their jalapeños, but other markets simply associate corking with certain types of peppers.  Jalapeños with corking are spicier than their unlined counterparts. 

A pepper’s spiciness is influenced by its capsaicin levels, which vary depending on the cultivar or the pepper’s specific genetic profile. Environmental conditions, likely including the same ones that lead to growth cracks, can also up capsaicin levels.