Beeduh, proteins in products may say just that, silk protein for instance. Some may leave off "protein" and just say what they are, like Keratin or Collagen. They can also be hydrolyzed, which means the protein has been broken into pieces, such as hydrolyzed wheat protein. They can also appear as amino acids, the building blocks of proteins, like silk amino acids.

You might want to check out Ingredients Commonly Found in Hair Care Products. It's a good reference for what's what in a product.
CG since 11/2011
2c /3a F /Mii, low porosity

Fall Products /Routine:
Clarifying: Herbal Essences Tealightfully Clean
Low Poo: Renpure Luxurious Argan Oil
CO: Suave Naturals Tropical Coconut or Daily Clarifying, V05 Strawberry or Kiwi Lime
Tresemme Perfectly (un)Done, Cure Care, V05 Kiwi Lime Squeeze, V05 Strawberry, Renpure Brazilian Keratin (old formula),
PT: IAGirl's as needed