If I ask you to name only 1 vitamin, which is commonly present in all vegetables, you would most probably say “vitamin C”. And you would be right. Our body needs vitamin C, also known as ascorbic acid, to be able o.a. to absorb iron, boost your immunity and protect your memory and thinking abilities while aging.
As you might know, vitamin C begins to degrade in fruits and vegetables immediately after harvest. So what do we need to know to benefit from vitamin C while using vegetables in our dishes?
Of course, using as fresh as possible vegetables is the best way to preserve vitamin C. The longer you wait using your fresh vegetables, the less vitamin C remains. For instance, green peas lose 51.5% of vitamin C during the first 24–48 h after picking!
Here, the storage temperature plays an important role. To give you another example, fresh peas stored at room temperature (20C or 68F) lose 50% of their vitamin C in 1 week, while fresh spinach loses 100% of its vitamin C in less than 4 days! It’s worth mentioning, that not all vegetables react the same way, if stored at room temperature. Carrots, f.e., lose only 27% of their vitamin C content when stored for 1 week at room temperature.
To slow down the decrease of vitamin C in fresh vegetables you can either refrigerate your veggies, freeze them or buy initially canned vegetables instead of the fresh ones. Each of these options has its own pro’s and contra’s.
Refrigeration can help save your vegetables from loosing promptly their vitamin C. So, loses of vitamin C in spinach are 75% if refrigerated. It’s better than 100% at room temperature, isn’t it?
But if you compare refrigeration with freezing, then the last one seems to be better in keeping vitamin C in your veggies. For instance, levels of vitamin C in fresh peas and fresh spinach stored in the refrigerator are lower after 10 days compared to the frozen ones. Interestingly, even in frozen vegetables, vitamin C continues to degrade. Losses after 1 year of frozen fruits and vegetables are appr 20%–50%, depending on the vegetable and its moisture content.
Freezing vegetables is not as destructive as putting vegetables in a can, but continued storage and subsequent cooking of frozen products result in more significant degradation of the vitamin C, while during storage of canned vegetables at room temperature for up to 1 year Vitamin C seems to be minimized less than 15%!
The main conclusion is that you should’t be afraid of using canned or frozen vegetables. They can contain similar or even higher levels of vitamin C as the cooked fresh ones (depending, of course, on the storage time and temperature, the cooking method and cooking time).
Curious? HERE is the source
