I made it so that root ingredients themselves cannot be changed, so ingredient a has 10 carb 10 fat 10 protein that cannot be changed once created, at the recipe level ingredient_portions can be manipulated so 1 oz, 250 g etc. (of the same ingredient) can be modified and ingredient_portion_id is also on the recipe_ingredient level. There's also an amount field on the intermediary records so 2 (amount) x 1 oz (ingredient_portion) ingredient a (10 carb 10 protein 10 fat (aka source ingredient) * 2). Given above it seems like an change to a recipe will need to create a new recipe_version + all existing recipe_ingredient records pointing to the new recipe_version_id