By Ross Goldenberg
May 11, 2011

After over 14 hours of cooking and 4 hours of tasting our Sous Vide Dulce De Leche, the results are in!
First a quick recap:

The Tasting Panel
The tasting panel, getting ready for our taste test. Notice that only 5 of the 7 samples are on the table. The 2, 4 and 6 hour samples were immediately dismissed as being more like sweetened condensed milk than like dulce de leche and not part of the blind tasting.
  • Ducle de leche is traditionally made by cooking sweetened condensed milk in a can for 3-4 hours. But the traditional method yields inconsistent results.
  • In order to find our perfect dulce de leche and be able to reproduce it consistently time and time again, we turned to our immersion circulator and the sous vide cooking method.
  • We cooked 7 samples of sweetened condensed milk in vacuum bags in a 180 degree water bath for 2-14 hours.
  • Each of the samples had a varying darkness from light tan (lowest time and carmelization) to a rich dark brown (longest time / highest carmelization).

My two friends, Dave and Kris, joined me and my wife, Laura, on Cinco de Mayo for a tasting. We tasted the samples plain, with a sweet pastry (churros), and a mild pastry (animal crackers). (Laura and I also ate it for breakfast the next morning with Nutella on our pancakes. Quite yummy, but not part of the formal tasting.)

Layers of Dulce
We combined the leftovers from all the samples into a single beaker at the conclusion of the tasting. Here you can see the variation of color/caramelization in a nice artistic form.

Here’s what we found:

  • Samples cooked for less than 6 hours are barely carmelized and more like the initial ingredient – sweetened condensed milk – than like dulce de leche.
  • The 8, 12, and 14 hour samples were far superior than the 6 hour sample, which had a grainy texture, almost as if the sugars in the sweetened condensed milk had re-crystallized.
  • The longer the cook time, the more viscous the texture. This is somewhat surprising because usually viscosity is a factor of how much water has evaporated during cooking. But since we cooked the samples in vacuum bags, there was no evaporation.
  • The 14 hour sample was by far the most sugary. When tasted with a churro, the hit of sugar to the palette was overwhelming.
  • The 12 hour sample was more saucy and less sweet than the 14 hour sample and preferred slightly.
  • The 8 hour sample had a good balance between the milk flavor and the sugar carmelization. It was by far the most complex flavor and was chosen by 3 of us as the favorite of a blind taste test. However it was slightly runny and probably best used as a sauce.

The Overall Winner: The 8 Hour Sample!