The phrase "different composition" means the combination or arrangement of different parts or elements that make something unique from others. Full definition
A similar experiment was done in 2009, with researchers concluding 31 Comparison of weight - loss diets with different compositions of fat, protein, and carbohydrates. (physiqonomics.com)
They focused on the satellite structures and showed that the energy separation between the satellite and primary peaks was diagnostic of uranium oxidation states over a broad range of compounds with very different compositions. (pnnl.gov)
For most meals, it was the same meals her family already was eating, just in different composition of foods and the size of the meals. (totalwellbeingdiet.com)