Functional responses of cold brewed white tea to high pressure processing

Abstract

AbstractChanges in functional characteristics of cold brewed white tea were quantified in response to high pressure processing (HPP). The multiple functional responses of total phenolic content (TPC), total antioxidant activity (TAA), and total caffeine content (TCC) were optimized using Box–Behnken design. Operational HPP conditions involved the ranges of pressure (300–500 MPa), solid (tea leaves)/liquid (water) ratio (SLR; 1–3%), and brewing time (120–600 s). Tea leaves/water ratio was determined as the most important factor with the highest rate of change per 1% increase in SLR for TPC (645.8 mg/L), TCC (11.48%), and TAA (5.09%). The optimum conditions were achieved using 300 MPa, 2.2% SLR, and 600 s brewing time and resulted in 91.9% TAA, 1949.2 mg/L TPC, and 17.5% TCC. APP appeared to be a promising alternative novel technique to minimize TCC and maximize TAA and TPC of cold brewed white tea simultaneously.Practical applicationsThe present study quantifies the multiple health‐related responses of cold brewed white tea to high pressure processing (HPP). The HPP approach adopted in the study provides cold brewed white tea with good quality and is cost‐effective in terms of small‐to‐large scale food industries. Joint optimization results can be used to improve the operational conditions of cold brewed white tea by related food processors.