Brewing practices to maximise levels of catechins and other compounds with functional properties in Azorean green tea infusions: comparison with composition of canned green tea drinks

摘要

The influence of infusion time, temperature and water characteristics oncatechins, gallic acid, theophylline and caffeine levels of Azorean green teainfusions was evaluated in two samples of green tea presenting differentcompositions to optimise brewing practices and maximise levels of compoundswith functional properties in infusions. Additionally, the compoundsunder study were quantified in commercial canned green tea drinks and levelscompared with composition of home-made infusions. An enhancement ofepigallocatechin gallate, epigallocatechin and epicatechin gallate levels, thecatechins with higher antioxidant activity, was observed as water pHdecreased and infusion time increased. No correlations were found betweenthe levels of gallic acid, theophylline and caffeine of tea infusions, and waterpH. The industry of canned green tea drinks produces beverages with acomposition of catechins and other bioactive compounds similar to that ofhome-made acidified green tea with 10-min infusion.