Incorrect.
As 1976_Child implied, different supermarkets specify different recipes for their own brand produce. I provide technical support to one of the largest food producers in the UK who have baking, preserves, cooking sauces, canning and other products in their portfolio. The constituents within every single product they make are different, even the seemingly identical 'value' products they put forward to the supermarkets. You have to be careful. For example, the difference in quantity of tomato paste in differing brands of tomato ketchup is quite staggering.