After asparagus is cut, it goes bad fairly rapidly. There are several easy ways to tell how fresh asparagus is in your supermarket produce section. Follow these guidelines to ensure that you buy the freshest asparagus available.
The Fronds at the Tip Should be Compact
As asparagus ages, the fronds start to spread out. Very fresh asparagus will have tip fronds that are compact and come to a spear point. The color should be green and light purple to dark purplish brown. They should be free of bruises or any mushiness.
The Cut Bottom Should be as White As Possible
This is a great trick for picking the bundle of asparagus that is freshly harvested. Once spears of asparagus are cut at the bottom, the the white flesh of the exposed stalk starts turning grayish-brown due to oxidation. The whiter the bottom, the fresher the asparagus. Simple!
Spears Should Not be Wrinkled or Wilted
Fresh asparagus is crisp and has a snap when broken. They are also more tender and it should be easy to make a little mark into the spear with your fingernail. This may not be something your supermarket appreciates, but its a good little trick for checking the crispness and tenderness of asparagus. As it get older, the asparagus gets tougher and woodier. The spears should be nice and green and should not appear shriveled or wrinkled.
Spears Should Not Be Rubbery
Although older spears, once they become rubbery, will probably have started to shrivel, it is good to know that a fresh asparagus spear is resistant to bending. It is more brittle and will want to break before you bend it very far. As they age, they become rubbery, stringy, and flexible and it becomes harder to snap off the bottom of the spears.
Bringing Back Old Asparagus Spears
Similar to how you can sometimes bring back shriveled old celery, you may be able to freshen up asparagus by placing the spears upright in a container of water, or wrapping the bottoms in a moist paper towel. Before doing so, cut off some of the bottom. this will not always work and once asparagus is too far gone, and has gone tough and rubbery, it is not likely to crisp back up. However, when you need to keep fresh asparagus for longer than a few days, you can store it in a container of water, or in a moist wrap, to keep it perky for longer.