I have been experiencing separation of ganache and have sought in vain for answers. When I make ganache by pouring hot cream over chocolate, then stirring, all goes well. But when I temper the chocolate to 84-86 F. (for white) and add cream plus flavorings at 105 F., the emulsion seems to be forming, then breaks with a mass and a separate pool of yellowish liquid. An immersion blender doesn't help, nor does the food processor. The only technique that has worked is to heat several tablespoons of cream and slowly mix the broken ganache into it with a whisk. This has worked every time (so far), although the result does not have the silky texture it should have.
I use several books for making ganaches, but the technique is basically from Peter Greweling (Chocolates & Confections). He states that a slabbed ganache should always be mixed with tempered chocolate. It is his recommended temperatures that I am using. The issue has occurred when I use Valrhona's Opalys white, although sometimes that chocolate (tempered) performs perfectly and mixes without a hitch. The Valrhona bag gives 84 F. as the desired working temperature.
What could it be? Temperature is a consideration, but I am using a Thermoworks infrared thermometer and also a Thermapen to check it. I am tempering with Mycryo, which I use for small batches. The recipe I was using most recently was Greweling's "toucans" (passion fruit ganache), with the change of tempering the chocolate before mixing it with the cream and passion fruit purée (because I was going to slab the ganache).
Any help would be most appreciated.
Thanks for the reply, which I found very interesting. Previously I had been doing what you recommend, that is, bringing the chocolate and the cream (plus flavorings) to the same temp., then mixing them. This sometimes worked, but sometimes did not. Some time ago I posted this issue on another forum, and a knowledgeable contributor wrote, "I try to never have my ganaches go under 35 degrees [95 F.] when I work them because under that temperature cacao butter sets....If you are using a chocolate that is at 55 degrees [131 F.] then your liquids can be at 28 [82 F.] ish you will have an end result in theory around 35 degrees. Other way, if your chocolate is at 35 degrees your liquids around 40 ish [104 F.], same result." As you can see, this is a different approach, and since it is what Peter Greweling recommends, I have been following it.
But because I have been having trouble (only with white chocolate) with this method, I will again try what you suggest and see what happens. Thanks again.
Thanks, Tom, for those ideas. I had heard the trick of adding some cold milk previously but not tried it, but I will do so--when needed (as I stated earlier, I have heated some cream and beat the ganache into it).
Why do you think the heated cream (at 41C/105F) is too hot for the tempered chocolate (at 29C/84F), whereas cream at 85C/185F is not?
I am interested to hear that you do not follow the advice of tempering the chocolate when slabbing it, as I have much better luck using the method of pouring hot cream over room temp. chocolate (which, of course, if it is coming from the bag, is already in temper).
Thanks again for the help.
In answer to the first question about adding warm cream to warm chocolate your desired combined temp is too much and it breaks, maybe try lowering the temp of the cream. The way I do it with 85 degree C cream onto solid room temp chocolate.
As for the reason not to boil cream, well I read this somewhere and then in my head my reasoning was that the hotter you heat cream the more the proteins denature (unravel) and then when they cool again they agregate with other proteins. And if your emulsion (ganache) is stabilised by the proteins then changing their form is likely to change their ability to stabilise the emulsion. Also practically this works very well, before when I used boiled cream, quite often I would have the ganache break, implementing the method of not boiling cream and only taking it to 85 degrees C I don't have a problem anymore.