The Effect of a Plant-based, Protein-dense Sauce on Essential Amino Acid Concentrations and Gut Fullness in Older Adults

The goal of this clinical trial is to determine whether meals fortified with plant-based high protein sauce (ProSauce) provide better metabolic availability of essential amino acids compared to meals with standard lower-protein sauce without resulting in excessive gut fullness and satiety. The main questions it aims to answer are: Does meals with high-protein sauce deliver better metabolic availability of amino acid profile? Does this high-protein sauce also not lead to excessive appetite suppression due to its liquid form? Researchers will compare high protein sauce to a commercially available standard low protein sauce. Participants will consume two meals, either protein-fortified or standard low-protein sauce, in a randomised order with at least a one-week washout period between each meal. The investigators will collect venous blood samples over a 6-hour postprandial period to measure plasma essential (and non-essential) amino acid and insulin concentrations. The investigators will also measure appetite-related hormones from venous plasma and assess subjective appetite using a visual analogue scale, taken in parallel with the blood sample time points.