Abstract: Ganache is delicious, but not everyone eats dairy. We examined whether coconut milk can be used for the creation of a non-dairy ganache. We ran a series of experiments. The answer is that, with some creative techniques, you can use it, but it does not come anywhere near to the real thing.
Introduction. Someone wrote a question on Seasoned advice about coconut based ganache and we got curious.
Background. We love ganache even more than pure chocolate, and make it often ourselves, so we think we have all the prerequisites needed to create and judge a coconut based ganache recipe. Our favorite ganache recipe 1
(which we used as a starting point) is: 100 g chocolate, 72% cocoa (only made from cocoa, sugar, and cocoa butter, no vegetable fat or emulsifiers); 100 g cream, at least 30% (non-UHT), 25 g butter.
Method. We prepared the base mix as follows: 25 g coconut milk were heated until boiling. They were removed from the heat. 25 g chocolate (72%) and 6g cocoa butter were added. Everything was left to dissolve. After 5 minutes, the mixture was whipped with a handheld mixer at the second-to-highest setting. This was Version 0. It was divided in two batches. Different versions were made from each batch by gradually adding guar (a knife-point-ful), egg yolk (1, in lieu of lecithine) and sugar (8g per batch). Each version was whipped for at least 3 minutes. The final versions (1c and 2b) where put for 30 min in the refrigerator, then taken out and whipped again. As there were no observable changes after the cold whipping, we do not treat them as a different version. We also made a small portion of dairy ganache for comparison purposes.
Results. These are listed in Table 1. The numbers in the ingredients columns of the table represent the order of adding the ingredients to the mixtures.
Table 1. Experiment results.
The final consistency of version 1c is documented in Figure 1. Note that the peaks do not drip and you can rotate the bowl at 180° without anything falling out. The piece of chocolate was added for color comparison.
Figure 2 shows a zoom of the blue bordered area in Figure 1.
Discussion. It is possible to make a profiterole filling with coconut milk based ganache, but it isn't quite like the real deal. Also, it resembles non-whipped ganache more closely than whipped ganache.
The basic ganache recipe can be done with coconut milk instead of cream and cocoa butter instead of butter. However, it tastes fattier than real ganache, and it is runnier. Unlike dairy ganache, whipping does not result in aeration.
We think that eliminating the cocoa butter altogether will somewhat alleviate the fatiness problem, but we did not test this proposal yet.
A thickening and or emulsifying agent can improve the ganache texture. Even though egg yolk improves aeration, is not a good choice, as it results in a slimy feel. Guar is a better solution.
The addition of sugar ruins the chocolateness of the taste. If bitterness is not desired, a sweeter chocolate (50%) should be used. Only dedicated sugar lovers or Americans should resort to adding sugar. In that case, it should be added before the guar (we would suggest dissolving it in the coconut milk before boiling it) as not to interfere with the texture of the final product.
Threats to validity. First, there was a single tester (the quasi-royal we). Second, this tester is already biased in favor of dairy products in general and specifically for dairy based ganache. Third, many interesting combinations (including xanthan gum and corn starch) could not be tested due to lack of resources.
Conclusion and outlook. We found the experiment very inspirating. It was also yummy. But we'd like to issue an warning: This experiment is dangerous. In the preparation phase, we discovered a penchant for guared coconut water deep fried in coconut fat we'd rather not have known about. Nevertheless, we are looking forward to offering the results for peer preview to a chocolate-loving lactose intolerant co worker.
References: 1
My own recipe book
Looking at your recipe, the most obvious thing to me is that there is no salt. Adding a small quantity of salt (say, 1/2 tsp) will enhance the flavors of the ingredients already present.
The second thing you might try is switching to dutch processed cocoa; many people find this has a more intense chocolaty taste.
You could try enhancing the overall flavor by adding a small amount of cinnamon (say 1/4 tsp) or instant espresso powder (perhaps 1 tbl). While these ingredients do not, in small amounts, overwhelm the flavor, they do increase its complexity and the impression of how chocolaty the fudge is.
Of course, you can increase the amount of cocoa powder (at least by ratio): simply increase the absolute amount of cocoa, starting with small increments of perhaps 1 tablespoon per test run. The problem with this method is not only that it throws off the sweetness balance, but also that it will eventually change the chemistry, possibly influencing the crystallization of the sugar phase which is what provides the smoothness of the fudge.
Finally, and more radically, consider reducing the amount of dairy, changing the milk for water, or reducing the amount of butter. The milk fats and milk solids tend to mask the flavor of chocolate. While I consider these part of the overall desirable balance of the fudge, since you after an intense chocolate experience, it may be worth experimenting with.
Best Answer
Cacao powder is not very soluble in water, so I'm gonna go out on a limb here and guess that the extra time allows for the cacao to incorporate better into the liquid.
The recipe includes actual chocolate nibs, but after it's melted into the milk / cream there's no extra flavor infusion by keeping it for a longer time.
12 hours sound like a lot: if you keep the mixture cold, it takes longer to dissolve (but not that long); if you keep it warm there's a risk of spoiling the milk. I can't think of a benefit to let the drink sit for such a long time.