For a project i'm currently developing, i have to manage 1 to many relationships and many-to-many relationships.
To do this, you must manage all your content in custom modules (like product catalog sample).
So in your case, you will create a custom module to manage Nutritional values (or do you want to use taxonomies?).
In the model of your product module, you will add a code like this:
var nv =
In your manager, in the copy method, you must add this line:
destination.NutrionalValues = source.NutritionalValues;
It is the same for your Categories.
If you use taxonomies for 'Nutrional values', you can create the taxonomy in the installation method of your module. If you want to use taxonomies, i can explain how to do this.
So you can build this in sitefinity. You can support translations into different languages, workflows...
You should use a module based on product catalog sample.
Hope this helps.