Recipe/Theory/Ingredient evaporation
Ingredient evaporation Most products are created by processing one or more ingredients. This processing can be explicit through cooking, grilling, etc. Or it can be implicit through simple storage. Many of these processes involve heat (even simple storage). These processes will influence the water content of a product. Some products will dry out (think of nuts). This drying affects the amount of a specific ingredient in a product. Different ingredients contain different amounts of water. Different products will release their water differently during drying.
The ingredients shown on a product are listed by weight. What weights are used here? Are these the weights before or after drying? Is the weight order affected by drying? What does the regulation require? And can or should we count on this? How could we get a grip on this? Single ingredient products give us some idea how this is handled. A product like tomato puree only has one ingredient: tomatoes. Most tomato purees also say something about the drying (double or triple concentrated). But for many other products it is not indicated how well they are dried (nuts for instance). One would expect that drying does not affect the nutrients: if there are x% of a nutrient in the original ingrient, there will also be x% in the dried ingredient, i.e. fat, carbohydrates, fibre, proteins and salt do not evaporate. For products with multiple ingredients we now have two possibilities: the listed ingredients order reflects the dried ingredients weight distribution or the original weight ingredients.