Have you ever bought jalapeno peppers from the grocery store and have some either be so lacking in heat it could be confused for a small bell pepper or so hot a small piece will almost bring you to tears?
Here’s an easy tip for choosing jalapenos that can help you decide which ones to pick for your recipe. Jalapenos progressively get hotter the older they get, starting light green and turning darker until it eventually turns a bright red. As they age on the vine, they develop white lines and flecks, like stretch marks or stress marks running in the direction of the length of the pepper. These are called striations or what many pepper growers call “corking”. The smoother the pepper is, the younger and milder it is. The more white lines and the darker the color, the older and hotter it is. There is still plenty of variation among individual pepper subspecies but it is pretty safe to say that a red jalapeno can be pretty hot if it has a lot of striations. It should also be noted that it will also be sweeter.
The bottom line is that if you are trying to avoid the hottest jalapenos, say for an appetizer dish for a party, pick the jalapenos that are lighter green and smooth without any striations. If you are looking for some heat, find a red or green one with plenty of white stretch marks. Note that this is just a generalization and you can find hotter than normal peppers without any white lines but your chances of picking a mild one are better if you go for smooth.
It’s widely known that capsaicin is the chemical that gives peppers their heat but one additional fact that’s good to know is the capsaicin is concentrated in the seeds and the sack around them. Is it also possible that the more mature jalapenos have more of their capsaicin distributed throughout their flesh than the younger ones? Of course, try eating several peppers of different heat ranges and get back with me.