Recently, in a laboratory outside Seattle, I ate a piece of buttered toast that I will remember for the rest of my life. The bread itself was not extraordinary, but it was spread thickly with the brightest-green butter I’ve ever seen. It was not true butter, but rather an extract of pure green peas. Fresh peas are blended to a puree, then spun in a centrifuge at 13 times the force of gravity. The force separates the puree into three discrete layers: on the bottom, a bland puck of starch; on the top, vibrant-colored, seductively sweet pea juice; and separating the two, a thin layer of the pea’s natural fat, pea-green and unctuous.
– Paul Adams, Future of food: Drinkable bagels and beyond
As the first reviews began coming out from the 30 course dinners held by the Modernist Cuisine team, everyone mentioned the pea butter in particular. A pretty simple recipe, you take pureed peas and spin them in a centrifuge to extract the pea fat. I gave it a shot at my house, taking a can of peas, blending them, and spinning them for 30 minutes. Nothing good came of it and the layers did not seem to separate. I was stumped.
Luckily, I was able to talk with chefs Maxime Bilet and Anjana Shanker at the Modernist Cuisine book launch and they were able to clarify a few things for me:
- Use frozen peas
- Blend them with nothing else
- Spin for 90 minutes
That seems simple enough. So I went home and went at it.
Visualize Whirled Peas
The chefs recommended a bag of high quality organic peas. My local store had Kroger brand. Well, hey, I gotta start somewhere. I brought home a bag and threw them in the Vita-Mix for their first spin of the day. It ended up being a very bright green frozen powder. I put the pea dust into one of my centrifuge containers and filled the rest of the containers with water as counterweights.
When talking with Chef Shanker, I asked how powerful their centrifuge was that she used for the pea butter, and she said it was 10,000 g’s. So I had to calculate how long mine would spin at, since my centrifuge only goes to 1520 g’s. Since the relationship is linear it’s straightforward to figure out:
10000/1520 = 6.58
6.58 x 90 = 592 min.
592/60 = 9.9 hours
Ten hours in the centrifuge? Mm. I started around 3pm and didn’t feel like waiting until 1am to see the results. So I decided 5 hours was plenty.
She also mentioned that it was good that I had a refrigeration unit attached. The reason is two fold: 1) so the food doesn’t cook; and 2) it keeps the pellet together, providing better separation. I checked my centrifuge temperature with and without the refrigeration unit. Without, the chamber got to 124F. With the unit turned on, it was at about 70F. So a significant difference to be sure.
And after five hours, I pulled out the peas and saw the results. Three separate layers: a pellet of pea meat, a thin layer of pea fat and a supernate of pea water.
One thing to note is look at the bottom of the container as compared to the photo of it prior to spinning. Five hours in the centrifuge completely distended and reshaped it. Luckily, it didn’t crack open.
I scraped off the fat and put it on a piece of bread. Pure bright pea flavor. It’s really, really good. The pea pellet and pea water were also striking in their own way as well.
I’m a little concerned about the wear and tear on the centrifuge since I will be needing to be spinning it for long periods of time to get their results, but it performed great for a five hour run. Cooking of all types teaches you patience, and in this case as in others, the wait is well worth it.