I use canned green chiles in my cooking often; jalapenos I usually buy fresh, but I have used jarred and canned as well.
What’s the difference between these two popular peppers?
To be clear, green chiles can refer to many different kinds of peppers – I am specifically thinking of the canned ones you see in the store.
Canned green chiles are typically one of two types: Anaheim, or California chiles; and Hatch, or New Mexico chiles.
Jalapeno peppers then, may or may not be hotter than green chiles – but for me they are hotter, because I typically only see mild green chiles in the store.
(Of course, it should go without saying, the hotness of peppers can vary greatly depending on growing conditions and other factors.)
In conclusion: The canned green chiles found in the Mexican food section, unless labeled otherwise, are much milder than jalapeno peppers. I wouldn’t swap them out in recipes.
Also, green chiles tend to be canned, and are roasted; jalapenos are found fresh, canned, or jarred. Green chiles come from California or New Mexico; jalapenos originated in Mexico.