Yes, you can use the Mx Model Reflection module and retrieve that information from the database after the model reflection module is installed and the data is refreshed.
The way I interpret this question is that you're using inheritance where Product is you generalization. You want to know the types of Products associated.
I think you can do this only in a Java action by using IMendixObject.getType() (which I would hope returns the full name of the type, but I dunno since it's not documented properly).
So create a Java action that has one input parameter, a generic object type thing. Only code this owuld contain would be:
{
if (InputObject == null) return null
return InputObject.getType()
}
or something along these lines.
Then you can call this Java aciton for every Product in your ShoppingCart.