The influence of domestic culinary processes on the Trolox Equivalent Antioxidant Capacity of green tea infusions

Abstract

This paper presents an investigation into the influence of several culinary factors, such as water temperature, infusion time, stirring and dosage form, on polyphenol content and antioxidant capacity (TEAC values) during the domestic preparation of green tea. The results obtained show that water temperature and infusion time strongly influence total polyphenol levels and the antioxidant capacity of green tea. Temperatures of 70–80 8C together with infusion times of 3–5 min produced greatest effect, in this respect. At 90 8C, extraction was faster and more effective. However, prolonged infusion at this temperature may cause a loss of polyphenol compounds and, consequently, of antioxidant capacity. Factors such as agitation and dosage form do not seem to have much influence. Furthermore, it was found that pure green tea infusions have higher antioxidant properties than do blends of green tea with aromatic herbs and fruits.