Processing Technologies for the Extraction of Value-Added Bioactive Compounds from Tea

Tea (Camellia sinensis) is the most widely consumed beverage in world, with an excellent source of bioactive compounds such as catechins, caffeine, and epigallocatechin. There increasing trend to extract these deliver them value-added products. Generally, extraction polyphenols other functional from different parts tea carried out using solvents (e.g., water, water–ethanol, ethanol, methanol, acetone, ethyl acetate, acetonitrile). The efficiency depends on type polarity solvent well applied process. Several conventional techniques, boiling, heating, Soxhlet, cold extraction, are used ingredients. However, procedures unsuitable for achieving high yields biological activities due long times brewing temperatures heating methods. Many efforts have been food pharmaceutical industries replace techniques innovative technologies microwave (MAE), ultrasonic (UAE), pressurized liquid (PLE), pulsed electric field (PEF), supercritical fluid (SFE)), which fast, safe, energy-saving, can present eco-friendly characteristics. These proven improve recovery rate phenolic-based antioxidant increase their efficiency. In this review, application novel processing leaves reviewed. advantages drawbacks also highlighted.