Monday, April 9, 2007
Coffee Ice Cream
Sometimes when I'm on the bus commuting to and from work, I like to think about flavor combinations (white chocolate with green tea, almond extract with lychee). Sort of like matching colors or clothes, but instead debating whether certain flavors compliment each other. I spent some time thinking about which ice cream flavor would be best for the Nutella brownie ice cream sandwich. In the end I chose coffee because the chocolate and hazelnut flavors combined with coffee reminded me of a hazelnut mocha.
Most of the coffee ice cream recipes I found called for instant espresso powder so I went out and bought some (I read that Medaglia D’Oro is a good brand). Since I had never made homemade ice cream before, I researched how to make the ice cream base. Some recipes were simply shocking - one called for an alarming 9 yolks! Most recipes used either a 2:1 (resulting ice cream of around 15% milk fat) or 1:1 (20% milk fat) ratio of whole milk to heavy cream and a ratio of 2:1 yolk to liquid. This got me thinking, was it possible to make homemade ice cream taste rich and creamy but use less cream and less yolks? In this recipe, I used only 2 yolks (since I had used 2 whites the day before) and 2 cups half and half, which is a combination of milk and cream that is around 11% milk fat.
I think I skimped too much on the milk fat and yolks in this recipe. The custard did not thicken either because I did not heat it up sufficiently since I didn’t have a thermometer I was afraid of overcooking the custard or because the yolk content is too low. Overall the conclusion from this first experiment is that the ice cream was okay but not perfect. The consistency was not icy but it wasn’t creamy either (unfortunately the photo makes the ice cream look really icy for some reason). Half and half and 2 yolks just isn’t enough for the rich and smooth mouth feel of really excellent ice cream. Next time, I’ll have to use more egg yolks and more cream.
Coffee Ice Cream
2 C half and half
2 egg yolks
1/2 C sugar (it was a little too sweet for me so next time I will use 6 Tbsp instead)
2 tbsp instant espresso powder
1/2 tsp vanilla
Optional: 1/4 C chocolate covered coffee beans, chopped.
Whisk yolks with sugar until the mixture is thick and pale yellow, about 2 to 3 minutes. It should fall from the whisk in ribbons.
In a saucepan heat 1 cup of half and half until 180º (I didn't have a thermometer so I just winged it). While whisking the yolks, slowly drizzle 1/4 cup of the hot half and half into the egg mixture, repeat with another 1/4 cup until the whole cup of the half and half has been added. This tempers the egg yolks and brings them up to a warm temperature without scrambling them. A neat trick is to wrap a damp kitchen towel around the base of your mixing bowl. This prevents the bowl from slipping around on the counter and frees your hand from holding the bowl to both drizzle and whisk.
Whisk in the espresso powder and salt to the custard mixture.
Add the custard mixture back to the saucepan over medium low heat and heat it up to 180º. The custard is supposed to thicken but mine didn’t. To test if it is thickened enough, dip a spoon in the custard and run your finger along the back of it, if the edges remain clean then it's done, if the edges run and blurs then it's not thick enough.
Chill the custard in the fridge for a few hours until cold. After the custard is chilled, whisk in the vanilla extract and the remaining cup of half and half. Freeze in an ice cream machine according to manufacturer’s instructions. A few minutes before the ice cream is done add the chopped chocolate covered coffee beans if using.
Elise has a great coffee ice cream recipe that uses whole beans (can be made with decaf beans). I’ll have to try making coffee ice cream this way next time.