Baby leaf spinach is naturally rich in ascorbic acid. During growth the plant can be stressed by for example high or low temperatures, excess or deficiency of water, high or low fertiliser levels and so on. The theory is that mildly stressed plants will synthesise high levels of antioxidants like ascorbic acid. Leaves with high antioxidant content are supposed to perform better during the shelf life (the time from harvest until you open the bag of ready-to-eat baby leaf spinach).
Vitamin C, or ascorbic acid, is an important antioxidant in plants. When the molecule reacts with oxygen, gets oxidized, dehydroascorbic acid is formed. If the plant is in good condition dehydroascorbic acid will soon be reduced back to the active ascorbic acid state. After that the molecule is ready to react with oxygen again, and thereby fulfil its antioxidant function (preventing cell damages and slow down ageing processes). The amount of ascorbic acid and a higher ratio of ascorbic acid to dehydroascorbic acid can probably be used as a prediction of how well the plant is prepared for future stress, like the harvest process and post harvest handling.
Harper Adams University College
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