When a Jalapeno Peppers is fresh and ripe it will be a green in color and have a smooth skin to it and as the Jalapeno Pepper ages on the plant it goes from green to red which usually makes it hotter.
But if you take the Jalapeno Pepper off the plant when it's green and fresh the skin of the Jalapeno Pepper should be smooth without wrinkles.
When a Jalapeno Pepper is beginning to lose it's freshness and going bad the skin of the Jalapeno Pepper will begin to wrinkle.
However wrinkled Jalapeno Peppers doesn't always mean that they are bad or spoiled yet and are usually still safe to eat as long as it hasn't changed to a brown or other color other than red and as long as the Jalapeno Pepper doesn't smell bad.
When Jalapeno Peppers are beginning to wrinkle on the skin it's a sign that the Jalapeno Peppers are going bad.
However even when the Jalapeno Peppers are just a bit wrinkled they can still be safe to eat as long as the Jalapeno Peppers do not have a bad smell to them or the color hasn't changed to a brown or other color other than red.
Red colored peppers usually means the peppers have gotten hotter but if the Jalapeno peppers turn other colors such as brown or possibly grey then they are usually bad and should be thrown out.
The Jalapeno Peppers when bad will usually have a bad smell to them or at least an off smell to them along with the wrinkles.
If the Jalapeno Smells okay and is wrinkled then it's safe to eat as wrinkled Jalapenos does not always mean they are bad but it is a sign that they are going bad.
Jalapenos should last for a few weeks in the refrigerator or at room temperature and sometimes longer but usually after a month they are going bad and usually need to be thrown out.