The efficient utilization of summer and autumn tea resources is a key issue for the sustainable development of the tea industry, but the traditional processing methods are difficult to take into account the functional activity and nutritional characteristics of tea protein.The purpose of this study was to reveal the regulatory mechanism of high temperature and high humidity air flow percussion blanching (HHAIB) treatment on the structure and functional properties of tea protein-polyphenol complex (TPC), and to evaluate its application potential as a delivery carrier for curcumin.The summer and autumn tea powder was treated with different HHAIB treatment times (0-210 s), and the structural changes of TPC were characterized by FTIR and fluorescence spectroscopy, and the stable Pickering emulsion properties of TPC-pectin complex were systematically evaluated.The results showed that the secondary structure of TPC was significantly transformed (α-helix to β-folding) and the molecular interaction was enhanced (fluorescence intensity increased) after 150 s treatment.The antioxidant activity of the 90 s treatment was increased (the free radical scavenging rates of DPPH and ABTS cation were 32.07% and 35.40%, respectively), and the constructed emulsion system showed excellent stability (encapsulation rate of 79.13%, thermal stability retention rate of >70%) and controlled release characteristics (intestinal stage curcumin retention rate of 78.85%), and the final bioaccessibility reached 67.78%, which was 32.51% higher than that of the control group.This study clarified for the first time the molecular mechanism of HHAIB treatment to enhance functional activity by regulating protein conformation, which provides a theoretical basis and technical support for the development of a high-efficiency nutrient delivery system based on tea protein, and is of great significance for promoting the high-value utilization of summer and autumn tea resources.
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