Rheological behaviour of selected commercially available baby formulas in simulated human digestive system

A variety of formulas are available in the global market for infants (<12 months old) who do not have access to mother's milk. The rheological properties of four different commercially available infant formulas - newborn, anti-reflux, soy and lactose free - in an in vitro digestive system were investigated. The enzymatic saliva when mixed with the formulas did not influence their viscosity in the mouth possibly due to the short residence time. Systematic measurement (every 15 min) of viscosity during gastrointestinal digestion process revealed a decrease in viscosity as time progressed. The most interesting observation was that the viscosity of the anti-reflux formula was relatively higher compared to the other formulas throughout the simulated gastrointestinal digestion process. The results suggest that viscosity of the infant formula in the stomach may have a role to play in preventing gastroesophageal reflux. (C) 2014 Elsevier Ltd. All rights reserved.