9 May 2010

Foolproof chocolate Chantilly, part 2:3. Earl Grey milk chocolate mousse with coffee/cocoa nibs

Numerous blogs, web sites and newspaper articles have picked up variations of the "molecular gastronomic recipe" for making chocolate mousse with only chocolate and water first presented by Hervé This. However, most these recipes tell you to try-and fail. I have for some time felt that there is a need for making this recipe foolproof. And on top of it all, it's quite straightforward to make as long as you're precise with the measurements.

This post is the second out of three on chocolate mousses: white-, milk- and dark chocolate. Part 1 was white chocolate mousse w/ginger. I've chosen to give recipes for mousses with added flavours rather than the pure ones. Hence, the recipe might not work out properly if other ingredients, or pure water, is used as liquid.

The main reason for doing these experiments is that most of the recipes on the "molecular gastronomic mousses" tell you to try and fail until you're satisfied. That's ok if you are to serve the mousse right away. However, the mousse will firm up upon storage, starting after 1-2 hours I want a recipe I can trust even when the mousse is kept in the fridge, not having to make it or, even worse, repair it while the guests are waiting.

Video shows texture of mousse after one night in the fridge made according
to recipe below. Also some microscope pictures of the same mousse

4 portions

Strong Earl Grey tea made from 2 dl (200 g) water and two tea bags (I used Twinings)
150-170 g milk chocolate (Freia "lys kokesjokolade")
5 g of cocoa nibs or coarsely crushed coffee beans

Mixer or hand whisk (steel balloon whisk)
Bowl for whisking
Measuring cup or scale/balance (preferably the latter for precise measurements)
Sink with ice/snow (preferably) or cold water
(Bowl/pan of hot water)
(mortar & pestle)

Make strong tea by steeping two bags of tea in 2 dl water for 5 minutes (loose tea would of course work fine, but tea bags are easier for measuring purposes). If using coffee beans, pound lightly in mortar&pestle to get small bits (but not powdery). Break chocolate in small pieces and put in metal bowl. Measure out 1 dl (100 g, discard the rest) of the tea, add to the chocolate and heat while stirring gently until the chocolate in melted into an even mixture. Using a bath of hot water or gentle microwaving works fine. Move the bowl to the cold sink and start whisking, stop as soon as the mixture takes a lighter colour and becomes light and creamy, however still slightly liquid. If it becomes grainy, melt and whip again (might occur upon prolonged whipping, seemingly). However, if the texture is smooth to begin with you're most likely safe and it will stay that way upon storage. Add either cocoa nibs or coffee and fold in carefully. Leave the mousse in the fridge for at least 1 hour to stabilise. It is still fine the next morning as well.

Tip: if using cold water bath, take care not to splash water from the bath into the chocolate (if so happens you have to start over. If you trust the water from the sink to be safe, you might melt the mixture, add some more chocolate and go for the try-and-fail tactic).

Milk chocolate Chantilly with chocolate:water
ratios 150:100 (upper) and 170:100 (lower)

The mousse is considerably lighter and more airy than the white chocolate mousse described in part 1. The balance between chocolate and tea is good, both the tea flavours and the bergamot (two links) flavours are subtle but not overpowering; the chocolate is the main player. I've had several people blind testing this and none of them were able to pinpoint that it is in fact tea (or Earl Grey) although the flavour is noticeable. I suppose it is simply the unexpected combination. If coffee beans are used, you get to play on the combination of coffee, tea and chocolate all combined in one single dessert. And indeed, they play very well together. The flavour is not very overpowering and the mousse stands well on its own feet. However, it is still quite rich and you won't be able to eat very much (unless you're an extreme chocoholic). The white chocolate mousse (or sauce) from part 1 plays well together with this one as well, and whipped cream or ice cream would of course also work fine. Addition of coca nibs introduces an unsweetened cocoa flavour, whereas coffee gives a contrast to the sweetness.

This mousse is much lighter than the white one. However, while whipping the volume does not increase as much as double cream or the dark chocolate (part 3). It is still a combination of an emulsion and a foam. Using chocolate : water ratio of 1 : 1 results in a thick sauce, higher amounts giving an increasingly thick consistency.

The picture shows a microscope image of the mousse at 400 x magnification. Although I've deliberately chosen a region with extra few bubbles for the picture, the amount of air bubbles is generally low, which explains the dense texture of the mousse. Increasing the amount of water/ginger extract results in the mousse being more liquid (less viscous). When the amount of water is doubled you get a thick creamy sauce with many more and larger air bubbles (a version is worth a try in its own right, really).

Addition of cocoa nibs or coffee introduces a welcome texture contrast. Cocoa nibs are somewhat more soft and (occasionally) chewy, whereas the coffee is crisp and brittle.

Long storage, say more than 12-18 hours, results in the mousse starting to "dry out" along the rim. For storage, collect the mousse in a small heap and cover with plastic.

The first time I experienced the Earl Grey-milk chocolate combination was at a hotel restaurant and I was astounded by the pleasant flavour combination. Scanning the food pairing web site, however, I could not find any apparent flavour pairings between these ingredients. Of course, the principle of common flavour elements is not a prerequisite for a good match (see i.e. the "matmolekyler" blog for several sceptical comments to this principle).

Chocolate variety is chosen for ready availability in Norwegian shops and supermarkets. The variety used here was Freia "lys kokesjokolade" (a variety of milk chocolate for desserts and cakes). The constituents are:

Proteins: 7.3 %
Fat: 28.5 %
Carbohydrates: 58%

Unfortunately, the producer is not willing to give any more information on the ingredients (and the ingredients given on the package only add up to less than 94%). Compared with white chocolate, this contains more proteins and somewhat more non-added-sugar-carbohydrates. This is partly due to the cocoa solids (which are absent in white chocolate), but might also be due to different amounts of added milk solids. The reasons that the chocolate-water mixture does give a smooth mixture is thanks to the milk solids (mostly proteins) and, probably most importantly, added lecithin. The amount of sugar is lower compared to white chocolate, and this might in part be a reason for the mousse to become lighter (possibly the same reason as when making egg white foams such as meringue, see links in the egg white foam post for explanation). Also, the higher amount of proteins compared to fat might give a lighter foam.

This specific recipe has been tested at least three times with the same result every time, one of which was done successfully by our 13 1/2 year old son. If someone should experience that the recipe does not work as expected I'd be very happy to hear about it. I really want this to be a recipe that can be trusted.

This, H. "Formal descriptions for formulation" Int. J. Pharm. 2007, 344 (1-2), 4-8.

- Hervé This & Pierre Gagnaire: "Le beurre chantilly" (includes chocolate Chantilly)
- Hervé This, INRA page: "Vous avez dit Chocolat Chantilly?"
- Andreas Viestad, Washington post, "The gastronomer": "Like Water for Chocolate"
- Matmolekyler (Swedish food science blog)
- Flavour pairing: www.foodpairing.be (to my knowledge, there is no scientific basis for claiming that food with common flavour/aroma compounds do taste well together, but the idea is fascinating)


  1. Hey I find reading your articles very interesting!

    I tried making this today, using a milk chocolate with similar nutritional values to the ones you have states, almost identical. I did not notice the color change to a lighter shade while whisking so I probably messed up somewhere. It has been in the refrigerator for 3 hours but it is still very liquidy. used 100ml of the tea which weighed slightly more than 100gms, 110 or so which may also be the reason other than over wisking.

    Going to melt some more choclate approx 20gms and see if that helps. Will let you know how it goes

  2. Thanks for trying. The reason might be the chocolate variety. Since the amounts of various ingredients are vital, so is probably the amounts of emulsifiers, milk solids etc in each type of chocolate.

    If it doesn't turn into a mousse while whisking, it'll never do so even upon storage in the fridge. Your suggestion is correct: melt a small amount of additional chocolate together with the "failed" mousse (make sure all of it is thoroughly melted) and whip again on ice/cold water.

    Yes, plese let me know. It'd be interesting to know the chocolate variety/brand that you used as well.

    Good luck :)

  3. The company is Cadbury's and the brand is "Dairy Milk". I am from India and its the most widely available one around.

    What i realized looking at Heston Blumenthal's video was that you need to whisk really vigorously. I did this and it did turn into a mousse :). Did you have to whisk quite vigorously as well? My coffee beans were already in the mixture because I had to melt and re whisk so maybe this affected how vigorously I had to whisk. Also the texture was grainy. Not too sure why this was, maybe due to the quality of chocolate?

  4. Thanks for not giving up. This is very valuable information, and an excellent example that what lies in one's hands (tacit knowledge) is often very difficult to translate into words. Anyway,...

    ...Blumenthal's video is a very good starting point: http://www.youtube.com/watch?v=g28-9NVUHj0.

    There are a number of things that might be the reason for your result:

    Making the chocolate foam
    - Milk chocolate seems to give a different texture than dark chocolate (see blog post). Unfortunately, I haven't tried Cadbury's for this.
    - The type of whisk used does make a difference. Whipping by hand requires ideally a balloon whisk (with many threads) because you want to introduce lots of air. Using electric mixer usually makes the job easier, but overwhipping might be a problem (see below).

    Grainy but soft texture-problem
    - If you whisk for too long after you've reached the "magic point", it seems to go grainy. Melt and re-whisk. One idea might be to leave the coffee beans to the very end, after you've got a satisfactory result. Then gently fold the beans in.

    Grainy and brittle texture
    Higher relative amount of chocolate vs water gives this texture (almost like a ganache/truffle texture). If you want a softer texture, like on the video, add a tiny amount of water, reheat and re-whisk.

    If you make sure to measure the amounts very carefully, my experience is that the recipe does give a stable result every time.

    On Blumenthal's comments on the video
    The claim that "water is not the worst enemy of chocolate". It is indeed chocolate's worst enemy if you are to make something pure chocolate which is not supposed to be a sauce or mousse. His claim must be seen as anecdotal rather than as a fact. I've written about chocolate-vs-water previously: http://www.fooducation.org/2009/02/chocolate-part-1-why-it-seizes-with.html

    Good luck, ...again :)


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