What causes grittiness in icecream bought from the supermarket?

Question

Simple question.. I'm a pastry chef, so I know a few things about icecream--and the answer to my question is definitely NOT ice crystals. The particles in the icecream remain even after it is melted--and you can feel it on your tongue. It's almost as if someone dropped a bag of superfine sand into the batch. It's not a particular flavor either, sometimes it's just random.

Answer 1

It is most likely lactose crystals (milk sugar).  They can form if the ice cream base is not heated properly before it is frozen and also if the ice cream base is frozen too quickly.

Answer 2

ice crystals were my first thought, but youve covered that, the only other thing i can think of would be that the ice cream wasnt mixed well enough and there are undissolved grains of sugar in it

Answer 3

It's the cream, which I get in tubs of ice cream after a while... sometimes it's to do with how it's clotted and the particles just connect together after a while. I'm guessing it's pretty starchy...