Induced high viscosity-milkshake reduces energy intake at lunch without a substantial compromise in lipid digestion

Abstract

The effect of β-glucan was tested on microstructure, sensory-specific satiation, subsequent food intake, and in vitro lipid digestion. A high internal phase emulsion was prepared with 75 % milk fat and 25 % whey protein water dispersion, and added as the lipid source to milkshake matrices. Two milkshake variants, one with 1 % β-glucan and the other without fibre, were produced and characterised by microstructure and rheology assessment. Using a within-subjects design, twelve healthy participants attended the laboratory on two occasions. The session began after the same, familiar, home-based breakfast had been eaten, and then in the laboratory subjective ratings of hunger, appetite and satiety as well as subjective sensory and hedonic ratings of the milkshakes and other (uneaten) foods were repeated across the session. Participants consumed a milkshake preload followed 60 min later by an ad libitum test meal (first course of tomato pasta followed by dessert). Liking ratings of tested milkshakes were recorded along with two salty and two sweet foods. Results showed that the β-glucan-enriched milkshake exhibited significantly higher viscosity compared to the control, however, both milkshakes were equally liked. Intake of the fibre-enriched variant of the preload resulted in decreased liking post-consumption, compared to control. Importantly, energy intake from the second course dessert was significantly reduced by 50 % with the fibre-rich milkshake, while no difference was observed in intake of the tomato pasta first course. In vitro assays revealed no substantial difference in lipid digestion kinetics between the two milkshakes, suggesting that the viscosity effect did not compromise overall lipid digestion.