I am looking into developing a chemical profile of Spinach, Kale, Pumpkins and Beetroot (and similar vegetables) which could be further used in authentication of purees of these vegetables. The analytical question would be - how do I distinguish that a spinach puree is made of 100% spinach, and not of 30-50% another (cheaper/more available) leafy plant?

Given that a profile of semi-finished goods (juices/puree) of fruits are well studied, and we have several authenticity models - what parameters could be included in the authenticity analyses of such vegetable products? Drastical technological difference between fruit and vegetable processing should be taken into consideration as well.