Water and Chocolate Chocolate Mousse

Introduction and Framing

From Hervé This (interview):

"I invented chocolate Chantilly — how to make a chocolate mousse without eggs, just foaming the chocolate. I was very proud, I got prizes for that. Later I discovered you can make the same with butter, foie gras, or even olive oil, so the invention is nothing [big in itself].

I invented shallot aioli [a mayonnaise-like emulsion usually made with garlic]. Later, I realised that if you grind any plant or animal sample with oil you can make an emulsion. So the number of types of aioli is infinite."

Barebones recipe.

Discussion

Most recipes (Food52, Serious Eats) use 70%, semisweet chocolate, but my goal here was to determine whether a similar recipe would work for 100%, unsweetened chocolate. Some Internet comments seemed to indicate it was possible, but I really wanted to work out the right proportions, given different ingredients/brands.

The main issue is that unsweetened chocolate has a different fat content, and as This implies in his interview, this kind of foam works well with anything that's fatty. In fact, in these experiments it seems like the fattier the main ingredient(s), the tighter/thicker the foam, and the more quickly it sets. (And the more water needed to control the foam well.) This is borne out in my experiments.

Warnings and Notes

First, don't use the Internet to look up nutritional information/fat contents. When I was doing my initial research, I found false information on the TCHO chocolate's fat content (one Internet site asserted they had 71% fat, when the nutritional information puts fat at around 50%). Instead, just rely on the information provided in Nutritional Information by the seller.

Second, pay attention to Food52's recipe for technique notes on things that can go wrong and how to fix it. This recipe is very forgiving because you can vary ingredients, you can replace water with port (suggested by Blumenthal), liqueurs, infusions. I'd watch out for liqueurs that contain fat, so while certainly you ought to experiment with creme liqueurs and Advocaat, keep in mind that it might change the fat content, so you might need to use more total liquid than you otherwise would. I haven't experimented yet, but it's possible that alcohol in liqueur might change the dynamics too, so if you do do this, be prepared to experiment. But if you don't get the right foam in the end, it's fixable. You can just remelt, and add more chocolate, or more liquids, depending on the issue you encounter. At worst you'll just end up using more chocolate and getting more final product than you perhaps planned on getting.

Experiments

Date	Chocolate Brand	Chocolate Type	Ingredients	Fat % (by mass	% Cacao)	Chocolate Amt (g)	Water Amt (ml)	Sugar Amt (g)	Makes Approx (ml)	Sugar Type	Texture	Notes
20180526	TCHO	Dark Chocolate Critters for Baking	Cacao Beans	47.5%	99%	50 g	44 ml	10 g	120 - 180 ml	Granulated brown coconut nectar sugar	Too thick	Melted to a form too thick (add water). Set very quickly and too thickly. Slightly undersweet. Good, if intense, with whipped coconut cream.
20180526	TCHO	Dark Chocolate Critters for Baking	Cacao Beans	47.5%	99%	49 g	58 ml	15 g	120 - 180 ml	Granulated brown coconut nectar sugar	Just right	Melted and looked slightly broken/granular. Whisking smoothed it out. Set softly and much more slowly. Still undersweet but good for my tastes. Intense flavors, as usual for this cream/mousse, the water and foaming really opens up the fruity/acid flavors in the chocolate. Put in fridge to see if it sets up more.
20180526	Guittard	Gourmet Baking Bars	Cacao Beans	53.3%	100%	49 g (approx 10 squares)	58.5 ml	15 g	120 - 180 ml	Granulated brown coconut nectar sugar	Just right	Melted and looked slightly broken/granular. With more heat, smoothed out a little, but not entirely. Transferred to bowl in ice bath, much more liquid than similar TCHO mixture. More whisking/cooling seemed necessary to set up, but only about a minute in comparison to 10 - 20 seconds with TCHO mix. Again undersweet but good to my tastes. As usual, flavors really open up compared to tasting in bar form. Guittard also has a sort of bitter/smoky taste that comes out. Also put in fridge to see if it sets up more.
20180526	Ghirardelli	Premium Baking Bar	Unsweetened Chocolate	53.3%	100%	49 g (approx 3 1/2 squares)	58 ml	15 g	120 - 180 ml	Granulated brown coconut nectar sugar	Just right	Melted and looked, again, slightly broken/granular. With more heat, smoothed out a little, but not entirely. Transferred to bowl in ice bath, more liquid like Guittard mixture. Moderate whisking/cooling, about 1 minute. Again undersweet. In this case, profoundly/unpleasantly. Might try another 5 g of sugar later. Bitter taste is very pronounced (maybe try adding salt?).