Quality parameters and bioactive compound bioaccessibility changes in probiotics fermented mango juice using ultraviolet-assisted ultrasonic pre-treatment during cold storage

Ultrasound can be applied in fruit juice fermentation as an innovative non-thermal sterilisation method with product quality-promoting potential. In this study, the qualities changes in fermented mango juice (UFJ) pretreated by ultraviolet-assisted ultrasound (US-UV) during the 30-days of cold storage (4 degrees C) were evaluated. The essential qualities of UFJ were enhanced compared with the fresh juice and traditional fermented juice (thermal pre-treatment). Additionally, UFJ showed better performances concerning physical features (suspension stability, particle size, viscosity, and colour), pH and acidity, as well as bioactive compounds stability (soluble dietary fibre, carotenoids, total phenols, and ascorbic acid) than fresh juice during storage, revealing that the higher qualities of fermented mango juice were improved by US-UV pre-treatment. More importantly, the in vitro simulated gastrointestinal digestion validated that the bioactive compounds in UFJ had better stability and bioaccessibility than fresh juice during various storage periods, and lead to better antioxidant performance. As an effective and novel non-thermal technology, US-UV pretreatment can be considered a promising alternative method to thermal sterilisation in the juice industry.