Enhancing lycopene stability and bioaccessibility in homogenized tomato pulp using emulsion design principles

Abstract

The objective of this study was to examine the impact of oil, emulsifier, and texture modifier addition on the bioaccessibility of lycopene in homogenized tomato pulp. Different types (olive or corn oil) and levels (0 to 8 wt%) of digestible lipids, a protein-based emulsifier (whey protein isolate, WPI) and/or a polysaccharide-based texture modifier (sodium alginate, SA) were added to the tomato pulp. The addition of these substances increased the amount of lycopene liberated from the tomato tissues. WPI addition led to the formation of smaller oil droplets during homogenization that scattered light more strongly, thereby leading to a tomato pulp that appeared more turbid. SA addition increased the viscosity of the tomato pulp, thereby increasing its uniformity. The best storage stability of lycopene in the tomato pulp was achieved by adding 8% corn oil and 1% WPI. However, the best in vitro bioaccessibility of lycopene (61.5%) was achieved using 6% olive oil and 1% SA. Overall, our results show that lycopene bioaccessibility in tomato products can be increased by careful manipulation of emulsion properties.Industrial relevance: Lycopene is a strongly hydrophobic carotenoid found in tomatoes that contributes to their desirable appearance and potential health benefits. However, it has poor chemical stability and low oral bioavailability, which limits its beneficial effects. We show that the stability and bioaccessibility of lycopene can be improved by high-pressure homogenization of tomato pulp in the presence of specific food additives. This approach may be suitable for the large-scale production of tomato products with enhanced health benefits.