The viscosity of an enteral formula depends on the concentration and characteristics of which two components?

• A. Macronutrients and Fiber
• B. Carbohydrates and Protein
• C. Fat and Water
• D. Micronutrients and Fiber

Answer: (A)

Viscosity in an enteral formula is governed by how much solid material is present and how that material interacts with water. The two components that most influence this are the macronutrients and the fiber content. Macronutrients—carbohydrates, proteins, and fats—contribute to viscosity through their concentration and their chemical properties. The type of carbohydrate polymers and protein structures, how they hydrate, and whether they form gels or networks with water determine how thick the liquid becomes as solids increase. Fiber adds viscosity especially when it is soluble; soluble fibers form gels and trap water, markedly thickening the mixture. Insoluble fiber tends to have less thickening effect. So, the overall thickness of an enteral formula depends on how concentrated these macronutrients are and the specific characteristics of the fiber present.