My pesto turned solid. Why?

Question

Warning: I am a cooking noob. I might overlook something ridiculously simple.

Anyway, I just made my first pesto sauce (do you call this a sauce?). Basil, Parmesan cheese, garlic, etc. At the end, I added vegetable oil. All was good and I was proud. Put it on bread and on pasta, and it was very tasty.

However, I stored what I had left in a small jar in the fridge. Only one day later, and it became solid! You can clearly see that the oil had solidified. Why is this? In fact, I poured in too much oil and took some out, and what I took out I put it in the fridge, in a cup (just the oil). This is also one massive block. I am used to oil solidifying, but AFTER you use it to cook. The oil that I used has not been cooked, and the rest of the oil I bought at the store is stored in a cupboard, in its original packaging, and is still liquid.

What went wrong?

Extra question:

• Can I somehow still de-solidify this and still eat this?

Asked by user16441

Answer

Most pestos use olive oil, which solidifies at around 6 degrees celsius - just over the temperature of the average fridge. The shop-bought pestos you buy probably adulterate the olive oil with other kinds of oils.

In any case, you'll be able to eat your pesto just by leaving it out at room temperature for a few hours, or by just scooping it out and adding to your hot pasta.

Answered by Jimmy Breck-McKye

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