Food preparations fall in this Chapter provided that they contain more than 20 % by weight of sausage, meat, meat offal, blood, fish or crustaceans, molluscs or other aquatic invertebrates, or any combination thereof. In cases where the preparation contains two or more of the products mentioned above, it is classified in the heading of Chapter 16 corresponding to the component or components which predominate by weight. These provisions do not apply to the stuffed products of heading No. 19.02 or to the preparations of heading No. 21.03 or 21.04.