I've been making gratin dauphinois for family get-togethers for years with a combination of whole milk and heavy cream. But my sister has developed an allergy to carrageenan, an additive which is now in EVERY brand of heavy cream I can find locally, including the organic brands, so that's out. (Don't get me started on carrageenan. It's creeping into everything, and allergy issues notwithstanding, nothing I've read indicates that it's very good for us.)
Half and half is carrageenan-free. Has anyone used it in a potato gratin? I'm leery because when I've used it before in other dishes it has sometimes curdled, but I'm thinking that the starch in the potatoes and the binding action of the cheese may help to stabilize it. Thoughts?