There are a few ways to tell if Jicama has gone wrong. One of the best ways is by looking at its appearance. If it’s wrinkled and discolored, it’s likely to be overripe. Another sign that it’s overripe is if it’s bluish-green or moldy. If you spot any of these signs, throw it out and try it again later.
The skin of the Jicama should be firm and smooth.