Watermelon Tartare with a mango "yolk"

This is my attempt at Thomas Keller’s play on steak tartare – compressed watermelon and mango “yolk”.  The recipe is from his Under Pressure: Cooking Sous Vide cookbook.   I got to use some crazy hydrocolloids from Le Sanctuaire to create the mango “yolk”.   They are natural substances that effect the properties of liquids.  Just don’t make me pronounce some of this stuff.

Melissa's Produce

I’ve got friends in high places.  I’ve had the pleasure of working with Daniel at Vans for  about a year now.  It turns out Daniel’s family just happens to own Melissa’s Produce!   All of their produce is amazing!  Daniel was kind enough to bring in a bounty of watermelons, mangos  and tasty little pixies for good measure for me to play with.

“Steak Tartare”

Compressed Watermelon and Mango “Yolk”


  • 1 small seedless watermelon
  • kosher salt
  • extra virgin olive oil

Mango “Yolk”

  • 250 grams mango juice
  • 1.6 grams Kelcogel F
  • 0.4 gram sodium hexametaphosphate
  • 30 grams calcium gluconate
  • 0.4 gram ascorbic acid
  • 75 grams granulated sugar


  • 1/2 lime
  • freshly ground pepper

Watemelon, rind removed

Remove the rind from the watermelon.

Watermelon, sliced

Slice it.

Compressed watermelon

Compress the watermelon by using a vacuum sealer.  Mine didn’t compress all that much, so I smashed it up a bit in the bag and then compressed it again.

Mango juice

I juiced quite a few mangos in order to get 1 cup of mango juice.

Magic powders

This is the magic fairy dust I used, also known as hydrocolloids.

Tiny measurements

Tiny measurements require a tiny scale.  Place the Kelcogel F and sodium hexametaphosphate on a saucer.

Blend it!

Place the mango juice in a blender.  Slowly sprinkle in the saucer of the powders into the mango juice on low speed until they are fully incorporated.  Blend on high for 2-3 seconds, then strain through a fine mesh strainer.

Floating yolk

Pour 500 grams of cold water in a deep bowl.  Whisk in the calcium gluconate, ascorbic acid and sugar to dissolve.  Place another bowl of cold water next to it.  Drop a teaspoon of the mango mixture into the calcium gluconate mixture and let sit for 1 minute.  Very carefully remove with a spoon and place into the water.  You will have little floating “yolks”.

When you’re ready to serve, combine the watermelon with a drizzle of olive oil and a pinch of salt.  Place one quarter of the watermelon in a ring mold on a serving dish.  Top with a mango “yolk”.  Finish with a squeeze of lime and a grind of black pepper.