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Ever Wonder About Taking Bitterness Out Of Cucumbers?

My kid loves cucumbers. So I’ve been slicing up a lot of them to satisfy her voracious appetite which reminded me of how my mother used to prepare cucumbers. She used rub the cut surface of a cucumber end against the cut surface of the rest of the cucumber until some white stuff came out. She said it was to remove the bitterness. And she's not the only one who does this, lots of people do this to remove the "bitterness".

Now, I don’t follow this ritual and I haven’t received any complaints about bitterness. So I wondered whether bitterness in cucumbers was even a thing and I decided to look into it.

From a consumer’s point of view, a cucumber is a vegetable, but from a plant’s perspective, it’s a fruit that develops from a female flower, usually after insects pollinate it. The cucumber plant (Cucumis sativus) is a member of the cucurbitaceae, which includes zucchinis, gourds, melons and pumpkins. Wild forms tend to be more bitter because of chemicals called cucurbitacins, which keep herbivores from eating them all up. 

Cucurbitacins can be toxic in sufficient doses and occur in more than a dozen forms, labelled A, B, C, etc. Some scientists are looking into their potential medicinal value.  

The amount of cucurbitacin in a cucumber depends on both nature and nurture. Some varieties of cucumber, such as the type I find wrapped in plastic at the supermarket, have been cultivated not to synthesize certain cucurbitacins and so these may be inherently less bitter than my mother's cucumbers. They have a thin, non-bitter skin and slow developing seeds. Since cucurbitacins also tend to give people gas, the specially cultivated varieties are also called “burpless.”

I don’t know if I could say that in public, “Where do you keep your burpless cucumbers?”

If you prefer home-grown cucumbers, many of these varieties contain cucurbitacins, and that's good. because they'll keep away the creatures that would eat them before you get to. But if you want to minimize the abundance of bitter-making chemicals, you have to look after them. Irregular watering, improper fertilization or overheating can produce more bitter produce. The distribution of cucurbitacins also depends on the part of the plant and its age. On the cucumber itself, cucurbitacins tend to be more concentrated in the skin and near the stem. Growing up, my grandfather grew cucumbers in our backyard, so my mother was probably justified in her concern about bitterness. Cutting off the stem end and peeling the skin seems like reasonable advice, but I have still not found out whether or not what my Mom did makes a difference. If you are a home cucumber gardener, perhaps you can do some controlled experiments and share your results?

We have a lot of questions about food. For instance, why does spinach make our teeth feel funny? And what turns milk into yogurt