Exactly what is pesto sauce?

I often asked myself, "what is pesto?", even when I had tasted this fresh, delicious basil herb sauce in pizza and pasta recipes...

Pesto sauce is a paste made from fresh basil leaves, garlic, olive oil, parmesan, and pine nuts. Its humble beginnings go back to Genoa in the Liguria region of northern Italy hence the name (pesto alla genovese).

Historically speaking, what is pesto paste?

The origins of pesto are somewhat certain but there is evidence that ancient romans used to eat cheese spread called moretum which may be made with basil. The herb most likely came from North Africa, however it was first grown in India.

People have also found historical letters in the archives of Genoa that mentioned a dressing similar to pesto called “battuto d’aglio” (meaning battered garlic) already in 1600s.

It appears the Ligurians around Genoa took the dish and adapted it, using a combination of basil, crushed garlic, parsley, grated hard cheese ( parmigiano-reggiano, pecorino, etc), and pine nuts with a little olive oil to form pesto.

Growing Basil

The unique climate and ideal soil around Genoa makes this ideal place to grow a variety of basil balanced in taste and aroma. Often Genovese families often kept a basil plant in their balcony and similarly, captains used to keep basil plant on their ships during long journeys.

The best areas to grow basil is just outside Genoa city, the piece of land facing the sea from Pra to Pegli, zones found on the western outskirts of Genoa. The movement of the wrist is of great importance. It should be a round movement, allowing to squeeze the leaves and then crush them.

Now that you know what is pesto and its key ingredient, here is some info on making pesto...

Making pesto

The ancient method of preparing basil pesto recipe often uses a marble mortar or a wooden pestle. It is considered one of the best ways to prepare pesto at home. The movement of the wrist is very important. It should be a round movement, allowing you to squeeze the leaves and then crush them.

However, people nowadays, often used a blender to make pesto, something I don’t recommend. I say this because blending ingredients make them into a moist paste where you can’t really see the different ingredients. I have also heard people chopping the ingredients with a mezzuluna or a large half-moon pizza cutter, which can also work well.

The key to making pesto is not to mix / grind ingredients together at one time, but to do it one by one. For example, you chop the basil a bit, add more ingredients like the garlic, then chop some more basil, add another ingredient, chop, etc.

Is canning pesto possible?

Herbs, like basil, and oils are both low-acid and together could support the growth of the disease-causing Clostridium botulinum bacteria. Oils may be flavored with herbs if they are made up for fresh use, stored in the refrigerator and used within 2 to 3 days. Thus canning herbs is not possible.

Fresh herbs must be washed well and dried completely before storing in the oil. Pesto is an uncooked seasoning mixture of herbs, usually including fresh basil, and some oil. It may be frozen for long term storage but it is not possible to can it.

However, you can always freeze pesto to store it and use it a few months down the line. Return from what is pesto page to social appetizers homepage