BIG · Effect of bioactive compounds from novel tomato on glycaemia - short title (Bioactive compounds Impact on Glycaemia)

Combining nutrients that act synergistically and have potential to lower postprandial glycaemia is an important dietary strategy that can reduce the risk of developing non-communicable diseases. Within a starch-based food matrix, like bread, the presence of bioactive compounds (polyphenols and carotenoids) can lower or delay starch digestion, and therefore the postprandial glycaemic response. This shows potential for development of bioactive-rich starchy foods, as an alternative to conventional high-glycaemic foods. Variations in dose, form and processing can result in bioactive-rich functional foods with different glycaemic potencies, thus further studies are needed to determine the role of polyphenols and carotenoids from tomato during digestion. The aim of this project is to determine the impact of polyphenols and carotenoids from tomato (naringenin and lycopene, respectively) on nutrient accessibility and impact on glycaemia.I will investigate the interaction of naringenin and lycopene from an organically grown tomato paste enriched with tomato skin, previously developed by the host group, with starch and starchy foods. Nutrient release from a food matrix and digestion will be measured in vitro at a micro- and macrostructural level, using a single-enzyme digestion system and the INFOGEST standardised static digestion model. To determine the effect of naringenin and lycopene on glycaemia, I will use biological samples from healthy study participants collected before and after 4-week intake of tomato enriched paste, from an ongoing dietary intervention study in the host group. The use of tomato by-products (skin) is a sustainable option to fortify foods, providing added value to scraps without post-harvest extraction of bioactive compounds. Results from this study will provide new mechanistic insight into how tomato bioactive compounds modulate starch digestion and new fundamental evidence on their influence on glycaemia.