Making ice cream and fats don't dissolve in base

Question

I am making ice cream from this recipe:
http://www.seriouseats.com/recipes/2010/10/apple-browned-butter-sour-cream-ice-cream-recipe.html (the first variation)
Upon reaching the final mixing step for the base, I find that small clumps of something (I assume fat) are not dissolving at all in the mixture (I've stirred for 10+ minutes with no effect (I don't have a blender)). The recipe warns that I need to completely dissolve the "butterfat" in the emulsion, otherwise the ice cream will be "grainy."
What has happened, and how do I fix it? Preferably without buying exotic ingredients I won't use in the future.

I have deviated from the recipe in these ways:

• I have no strainer, so I did not brown the butter as much as is called for and then just let gravity work to strain out the brown particles. I wasn't exactly sure how much to let the butter cool before adding it -- I let it sit for at least 10 minutes before adding it, but it was still molten when I did add it. Within 8 minutes or so the stuff I hadn't added had solified, so it wasn't that hot.
• I have pre-made, refrigerated apple cider syrup, so I used that instead of the boiling apple cider. The nutmeg really did not dissolve at all in the syrup even after stirring, but I figured it would do so once I added the syrup-nutmeg mixture to the other ingredients.

Thanks for any help you can provide.

Update: I took Russell's advice and heated the mixture up while stirring. That worked to dissolve all the solids! Update 2: Recipe finally turned out as expected: interesting, not-very-sweet ice cream. Thanks everyone!

Answer 1

Looking at the ingredients in step 3, my guess is that the sour cream is causing the milk to curdle, possibly made worse by the heat from the melted butter.

You might try experimenting with first mixing everything except the sour cream together, then letting it cool completely, and then slowly whisking in the sour cream.

You might also try slowly heating the lumpy mix you already have, and see if whisking it over a low heat helps it to dissolve.

Good luck.

Answer 2

I don't know if you have made butter emulsions before, but they are quite temperature sensitive. It is like making a mayonnaise.

The recipe doesn't describe it in so many words, but what you were supposed to do is to keep the ice cream base at a temperature above the melting point of butter, 50 Celsius would have been a good point. Then you'd need to have your butter at the same temperature. Then whisk it over a bain marie slowly, always giving only a bit of butter into the base bowl, in a thin stream, under constant whisking. Doing it by hand would be possible, but requires a deep bowl and patience. A hand mixer or a stick blender would have been easier. This is the standard way to make butter-in-eggy-liquid emulsion, and it works without any grains.

It is probably easier to add the cider afterwards, do it gently so you don't break the emulsion.

It is normal for a ice cream recipe with lots of alcohol to remain very liquid in the ice cream maker. I made Leibowitz's zabaglione recipe recently, which has 125 ml of wine added to 800 ml base. It stayed very liquid even though I gave it 10 minutes extra. But after a day in the freezer, it became perfectly smooth, no crystals anywhere - again it must have been the alcohol, because I used no additives, not even salt.

I wouldn't insist that the recipe is bad before having tried it with the right technique and then seen the end result after freezing (not just out of the ice cream maker). But I agree that the instructions could have been clearer on temperature and technique, not everybody knows what you need to do to emulsify butter.