Effects of infusion conditions and decaffeination on free amino acid profiles of green and black tea

► Twenty free amino acids in black and green tea samples were investigated. ► Concentrations of each amino acid were monitored during tea brewing. ► Maintaining higher temperatures during brewing resulted in higher extraction rates. ► Decaffeination (> 50%) of tea resulted in 22% reduction in total free amino acids. ► Comparing to black tea, amino acids in green tea had lesser leaching rates.