The January 1987 issue of Bon Appétit had an article on truffles. That was the year of my parents' 50th anniversary, so I made hundreds from the interesting recipes offered in that issue. The "Island Truffles" were especially tasty: white chocolate, toasted macadamias, toasted coconut, rum, cream of coconut, sour cream, and lime zest. They were dipped in white chocolate to finish them. Nothing was said about tempering any chocolate, and I knew nothing about such things in those days. Those truffles came out perfectly (sometimes ignorance is indeed bliss). Last year I was asked to make some truffles for a high school reunion, so I pulled out that issue of Bon Appétit and made those truffles again. This time was not successful (at least not at first). The recipe calls for melting the chocolate with the cream of coconut. I did that, and the whole thing separated horribly. After trying many methods of salvaging the ganache, I put it in a food processor, and it came together successfully. Now, one year later, I am making those truffles again for a big event. Today I was very careful in melting the chocolate (I am dealing with 40 oz.). It refused to melt for a ridiculously long time, but I was determined not to make my (assumed) error of moving too rapidly. Finally I got it softened (not melted), but when I added the sour cream, it separated just like last year. This time the food processor trick did not work. You can imagine my panic--with 40 oz. of Valrhona at stake, not to mention my sanity. I chilled the mess, then used a hand-held mixer. That seems to have worked. It doesn't look great, but inside a truffle, who will know?
Now I want to understand what happened. I have a couple of clues: In the 1987 effort, I knew nothing about chocolate. I am fairly sure the white chocolate I used was what I would now know as "coating chocolate"--I think the brand was Peter's. So my first question is whether the fat used in that kind of chocolate would have made a difference. I know whatever the fat was, it's not as temperamental as cocoa butter. Second question: I wonder if mixing the real chocolate (last year it was Callebaut, this year it is Valrhona) with the cream of coconut does something to the chocolate that eventually causes it to separate. Perhaps I should melt the chocolate first, then start adding the other ingredients. On the other hand, in a typical ganache, one doesn't usually add the cream to the chocolate when the cream is unheated, but such a mixture would eventually emulsify with enough stirring. (Both my cream of coconut and sour cream were at room temp.)
This is far from a typical ganache, so I am at a loss as to what to do. Maybe a fake chocolate is what is required?
Any ideas would be most welcome.