Yesterday was revitalizing. Workshops tend to fuel my creative tank and yesterday's was no exception. Working with giant rotary evaporators, large enough to hold Aki, to make clear sour cream and onion potato chips and the aroma of Dr. Pepper will often do that to you. Lately I have been intrigued by a new (to us) approach to the process of encapsulating liquids. In the just published book Under Pressure, the first recipe includes the process for making a mango yolk using Gellan merely sheared into a mango puree and dropped into a calcium bath. In the recipe, sodium hydroxymetaphosphate is also added to the mango, I believe as a sequestrant, because mango contains a fair amount of calcium. We discovered this when we made an instant mango pudding using low methoxyl pectin. Unfortunately, I was unable to find out what sodium hydroxymetaphosphate is. We have made the assumption it is a close cousin to sodium hexametaphosphate, a sequestrant that we were introduced to by Ted at CP Kelco.
In reading the recipe I was taken aback by the fact that the Gellan was merely sheared into the mango puree with no heat needed. I had not heard of this technique and it warranted a call to Ted. It turns out that under the right conditions Gellan may be sheared directly into a base. After a long conversation on this and a few other subjects, Ted had planted enough seeds to fill a garden of ideas. Like seeds ideas need time to germinate. Another recent conversation, this one with Nathan, brought the encapsulation of Gellan to the table again. As he is writing a modern cookery tome when he mentioned his pleasure with Gellan encapsulation I took notice. We still had not tried the process though clearly we needed to because the approach was mentioned twice in the span of a few weeks .
Driving home from yesterday's workshop, brimming with ideas, Gellan encapsulation finally sprouted. We have witnessed the continued use of calcium and hydrocolloid reactivity. First it was calcium rich products dropped into alginate baths. Unfortunately, alginates are often tasteless and rob foods of flavor. Next we were introduced to and embraced the idea of dropping calcium rich and reactive flavor bases into pectin baths to encapsulate them in a fine shell of pectin. In looking at the recipe in the book a Gellan based yolk is dropped into a calcium bath. What if we flipped this technique around? We would then be able to control the calcium level in the bath with ease and have more flexibility in the product to be encapsulated. This was the theory. As Aki says, there is only one way to find out if it works.
I made bath with 0.5% Kelcogel F and 0.05% sodium hexametaphosphate. I sheared the sequestrant in first and followed with the Gellan. A quick straining and the bath was complete. I then took spoonfuls of yogurt and dropped them in the bath. The viscosity of the bath helped hold the yogurt in a roundish shape and the Gellan reacted with the calcium by forming a fine skin on the exterior. After a few minutes in the bath we pulled out the spheres and rinsed them in cold water. We then made a quick bath of honey and water to hold the orbs. To say that I was pleased would be an understatement. This morning I was like a ten year old on Christmas day. When I realized that because we were using Gellan, the orbs could be served hot as well as cold, things got even better.
Now comes the fun part, seeing what we can do with this incredibly simple and easy to work with approach to encapsulation. The permutations are endless, flavored baths for the encapsulation and a seemingly infinte array of possible fillings. Oh the places we'll go...