It depends.
Under normal circumstances, dried lemon slices are orange-yellow, with strong lemon aroma, high nutritional value and edible value. However, if the dried lemon slices come into contact with air during storage, they may be oxidized to black, which is a normal phenomenon. Generally speaking, as long as the dried lemon slices do not deteriorate, they can still be eaten normally.
However, if the dried lemon slices not only turn black, but also rot or smell, then it is not recommended to eat the lemon slices at this time.
As long as it doesn't go bad, it is drinkable.
Combined with the above situation, we can know that the browning of freeze-dried lemon slices is probably caused by oxidation with oxygen in the air, which is normal. Generally, as long as the lemon slices do not deteriorate and rot, they are edible, so there is no need to worry too much.
However, it should be noted that the nutritional value of freeze-dried lemon slices may decrease after they turn brown, and they are not as nutritious as before.
The main operations are as follows:
Lemon seeds contain a lot of limonin. Remove the seeds before soaking in water, which can greatly reduce the bitter taste of lemon.
Many people don't know that when soaking lemon slices, it is also very important to grasp the water temperature, because the sour taste and bitter taste of lemon will increase with the increase of temperature, so the temperature of soaking lemonade is not easy to be too high, and generally it can be kept at around 20-50 degrees.
It is best to soak the dried lemon slices in water immediately. If the soaking time is too long, the bitter elements in the lemon slices will be released, resulting in bitter lemonade.