Whipping cream is cream that contains at least 30% milk fat. Cream that has less than 30% fat will not whip. Heavy cream can contain up to 40% milk fat, and is sometimes used for whipping.
The structure of whipped cream is quite complex. A coating of milk protein. surrounds small globules of milk fat, containing solid and liquid fats. These globules stack into chains and nets around air bubbles. The air bubbles are also formed from the milk proteins, which form a thin membrane around the air pockets.
The three dimensional network of joined fat globules and protein films stabilizes the foam, keeping the whipped cream stiff.
Carageenan is a gelling agent that forms a complex with the milk proteins, adding bulk and strength. A small amount will make a large difference in the ability to hold air in the foam.
Mono and diglycerides replace some of the proteins in the coating around the fat globules. This lets the globules partially fuse together, to form the chains and networks that make up the three dimensional structure of the foam. There are natually occuring mono and diglycerides in milk and cream, but adding more makes the whipped cream last longer and helps achieve higher volume.
Sweeteners such as sugar and corn syrup are added for taste, but they also participate in the structure of the foam, and in the weight of the final product.
Natural and artificial flavors are also added, usually in the form of vanilla extract or synthetic vanillin or ethyl vanillin.