This week's ice cream is even more experimental than usual as it's a trial run for a more complicated version I'll be making in a few weeks. The inspiration was this post in the Desert Candy blog about making Thai iced tea ice cream using condensed milk instead of the cream. It would be easy enough to just switch the infusion from tea to coffee, but I think half the experience of Thai iced whatever is the swirled uneven mix of the two elements which is not just a pretty visual but makes each sip a slightly different flavor and texture. I'll have to do a coffee ripple sort of thing to emulate that, which is going to be another problem which will have to wait until my new coffee maker is delivered.
But first I wanted to make something closer to her recipe to figure out how to work with the condensed milk and to see how much it tastes like Thai iced coffee. Also, I wasn't sure the recipe was going to work at all. I've recently made another recipe from the same blog for fish in a pomegranate lime sauce that really didn't turn out at all well. I don't think she actually tested the version she had modified for the American kitchen.
So, I had to halve her recipe to fit into my churn, I switched out the tea for coffee, and I used just the yolks instead of whole eggs, but otherwise I followed the recipe unchanged. Trouble first arose when the solid-ish bits of the condensed milk just would not dissolve. That meant that when I strained out the post-infusion coffee, I strained out a lot of that, too, leaving this ugly muck:
I added a bit more along with the egg yolks and heated it up to 170 degrees for the custard. I think the heat makes the condensed milk coagulate a bit as there were still a lot of clumps despite all the stirring. (There were lots of specks of coffee left in the mix too, but that's my own fault for grinding a bit too finely.) Even after some serious whisking the results were pretty ugly and unappetizing.
Fortunately, the churn managed to break those bits up and the final results don't look too bad.
The texture is a bit more gooey than standard ice cream and it melts pretty darn quickly (which is typical of low fat ice-creams). The flavor is pretty much standard coffee ice cream. I think the 50/50 mix of condensed with regular milk diluted out the characteristic flavor that makes Thai iced coffee distinct. Also, it's rather more sweet than I'd like.
I wrote that last thought after tasting the ice cream straight out of the churn. After a night of ripening in the freezer, the sweetness has been dampened leaving an intense, pleasant coffee flavor. Most of the air I churned in had escaped leaving the ice cream with a dense, pudding-esque texture which isn't bad at all, even if it is disconcertingly sticky. It's good, but it isn't ice cream.
On the whole, I don't think the trade off of control over the sweetness (and the freedom to use sugar-substitutes) for the slightly lower fat of condensed milk is worth it. Particularly without added interest in the flavor and with a marked decline in texture. I've decided that when I do the coffee swirl, I'll just use a standard ice cream mix; the real question there is how to prepare the coffee for swirling and how to swirl without mixing.