Effect of fresh¿cut apples fortification with lycopene microspheres, revalorized from tomato by-products, during shelf life
Postharvest Biology and Technology
- Volumen: 156
- Fecha: 01 October 2019
- ISSN: 09255214
- Source Type: Journal
- DOI: 10.1016/j.postharvbio.2019.05.026
- Document Type: Article
- Publisher: Elsevier B.V.
© 2019 Elsevier B.V.Fresh¿cut apple browning has been conventionally tried to control with the help of ascorbic acid dips, although such antioxidant effect is limited. Lycopene, absent in apple flesh, is the carotenoid in nature with the highest antioxidant capacity, in special for its cis ¿ isomers. Tomato skin is a low cost by-product with very high lycopene content (7.23 g kg¿1) and high potential to be incorporated as an antioxidant agent in antibrowning dipping treatments. High lycopene extraction from tomato skin was achieved with a thermal treatment (75 °C, 1 h) favouring trans ¿ to ¿ cis lycopene isomerization with TiO2 nanoparticles. Lycopene extracts were highly encapsulated (encapsulation efficiency: 92.2%) with the complex coacervation method and the obtained microspheres were then incorporated in dipping treatments (0.5 (L0.5), 1 (L1) or 2 g L¿1 (L2)) during fresh¿cut apples processing, compared with an ascorbic acid dipping (AA; 10 g L¿1). Quality changes (colour, microbial, physicochemical and bioactive compounds) were studied up to 9 d at 5 °C. The L2 dipping controlled better the browning during storage, showing the lowest browning index among treatments (BI = 43.8) after 9 d. Furthermore, L2 dipping did not affect the physicochemical quality of samples, while maintaining a good microbial quality. Incorporation of lycopene microspheres also improved the bioactive quality of samples, still showing total cis ¿ lycopene isomer content of ¿ 20 mg kg¿1 after 9 d. Furthermore, chlorogenic acid, the predominant phenolic acid, content was enhanced by 56% in L2 samples after 6¿9 d. In conclusion, a dipping treatment of fresh¿cut apples including 2 g L¿1 lycopene microspheres reduced browning, while quality was maintained and some bioactive compounds even enhanced after 9 d at 5 °C.