Hi folks -
Been a while since I have posted but I tohught I would update on this.
We were finally able to connect the dots and get some raw milk from the Holsteins of Byebrook Farm in Delaware County NY (western Catskills, near Delhi). Their info is here http://www.nyfarmcheese.org/cheesemakers.asp?id=42
Looking to feature the milk as much as possible, we made two batches of Madagascar vanilla, Philadelphia-style (no eggs), and dialed back the cream component so it was about 75% milk / 25% cream. One batch was sweetened with regular white sugar and the other with raw Indian Jaggery/Gur brown cane sugar.
The result was pleasant, but I would fine-tune it in the future. The white sugar batch tasted a little bit too sugary sweet somehow. The jaggery batch was a whole different animal, with a beige color and an intriguing subtle fruitiness from the unrefined sugar (one person even guessed "olives?"). I thought of these more as experiments to evaluate the taste and impact of the raw milk in any event.
The texture of both seemed a little bit icier than our other batches, I wonder if the reduction in cream content might have contributed to that. All-milk recipes such as for gelato often have a texturing agent such as corn starch in them, maybe to counteract that?
As to the impact of using raw milk . . . .sounds funny to say, but I guess the ice cream was "milkier" or had a more prominent milk taste. It was not radically different from our other efforts, but the subtle nuances of milky sweetness and other dairy qualities seemed more in the foreground. I would definitely do it again.
Although this milk was unpasteurized, it had been homogenized. I would be interested to try making ice cream with unhomogenized milk also. And finding good quality cream that is not ultra-pasteurized!