Steam explosion treatment for improving the quality of Xuehua pear soup: Components profile, antioxidant and anti-inflammatory activity in vitro, its flavor and metabolomics study

In this study, steam explosion (SE) was applied to produce Xuehua pear soup (XPS) at different steam explosion pressure. The results showed that 0.3-0.6 MPa was the optimal pressure to improve the XPS quality. After SE treatment, the titratable acid of XPS decreased whereas it became darker. 0.6 MPa was the optimal pressure to enhance total flavonoid content and concentrated catechin, protocatechuic and rutin, endowing XPS with good antioxidant activity. 0.3 MPa was conducive to enrich arbutin, caffeic acid and gallic acid, endowing XPS with good immunomodulatory effect in vitro. XPS possessed the cake and caramel flavor due to SE treatment and its green, sweet, caramel and herbal odor increased. Finally, 5 metabolic pathways were screened to clarify the formation mechanism involving 21 metabolites. These results proved steam explosion had the potential to concentrated nutrients and improve flavor during food processing.