Why do two very similar products sometimes have (very) different grades?
Sometimes products that look very similar may use very different ingredients. For example, some demerara sugar is made from unrefined natural cane sugar, which includes the molasses of the sugar cane that gives it its light brown colour. Other demerara sugar is made from beet sugar, with some cane molasses added for colour and flavour. The production of sugar beets emits much less carbon dioxide than the production of sugar cane, resulting in very different sustainability scores for the two versions of demerara sugar.