green jalapeno peppers
How To Tell Which Supermarket Jalapeños Are The Spiciest
By Stacie Adams
Jalapeños have a Scoville range of 2,500 to 8,000 SHUs (Scoville Heat Units), which can be overwhelmingly hot. Thankfully, you can tell how spicy they are by their appearance.
The presence of white lines and marks typically means that the pepper had a stressful growing experience, which could increase the concentration of its spice chemical, capsaicin.
Selecting jalapeños with lots of stress marks may result in more heat than you can handle. If that’s the case, roasting them can reduce the spiciness for a milder experience.
Jalapeños that receive extra water can have a much milder flavor, so some farmers intentionally provide excess water to temper the spice and make it palatable for more people.
Other factors that influence the hotness of a jalapeño are how many seeds it contains, its genetics, and the size of the placenta, which contains capsaicin-producing glands.
In many cases, red and green jalapeños offer the same level of spiciness, which means maturation time probably doesn't have as big of an impact as the growing conditions.