Rhubarb is delicious. But the red to green-stemmed vegetables are not a daily meal. Because the oxalic acid it contains is considered a calcium robber. The North Rhine-Westphalia Chamber of Agriculture points this out.
The robber is more of a preventer. Because no matter how much calcium-rich food you eat: the oxalic acid from the rhubarb combines with the calcium to form the poorly soluble calcium oxalate, which is mostly excreted by the body unused.
Rhubarb: The greener, the more sour
Incidentally, the color of the stalk provides information about the intensity of the acidity: rhubarb with a green stalk and green flesh is particularly sour and, according to the Chamber of Agriculture, is suitable for jams and compotes. Red-stemmed stalks with green flesh have a slightly tart, less sour taste. They are suitable for savory dishes and pie fillings.
If the rhubarb is red-stemmed with red flesh, it even contains a slight raspberry aroma and is particularly mild. The ideal use is in grits or fruit salad. Especially tender sticks have light red stems with pink flesh and a mildly sour taste. In order to counteract the acidity, they like to add a lot of sugar. But you should only do that after cooking – this way you need less sugar, according to the tip of the chamber.