What is the difference between animal fat and vegetable fat? How can each contribute to the viscosity of gelatinised milk?
I'm not an expert on how this contributes to viscosity, but the main difference between animal and plant fats is the degree of saturation, animal fats being saturated, and plant fats having varying degrees of unsaturation. Unsaturation reduces van der Waals forces and lowers boiling points, their irregular shapes (due to multiple double bonds) also contributes to lower melting points, which is why plant fats tend to be liquid at room temperature, whereas animal fats are solid.