Google is looking at beefing up the structured data for ingredient lists. It's become common for some sites to:

1. have ordering + use grouping on their recipe ingredients with a header for the category of ingredient
2. use structured property/value pairs (ok, this has always been the case but we never even tried to let people give us this before)

So I'm proposing that recipeIngredient have its range expanded to <Text,PropertyValue,ItemList> from the current Text. I'll follow up with pull request within the next week.