Effect of drying and steeping temperatures on the phenolic content, antioxidant activity, aromatic compounds and sensory properties of cunila polyantha benth. Infusions

Abstract

Cunila polyantha Benth. (Lamiaceae), an aromatic plant endemic to Mexico, is used in traditional medicine as tea infusions. In this study, the effects of different drying and steeping temperatures on the phenolic content and composition, antioxidant activity, volatile composition, and sensory properties of C. polyantha infusions were determined. Commercial green tea (Camellia sinensis L. Kuntze) was used as a control. The phenolic compounds identified in the C. polyantha infusions by high-performance liquid chromatography (HPLC) include phenolic acids such as gallic acid, chlorogenic acid, caffeic acid, and p-coumaric acid, flavonoids such as epigallocatechin gallate, protocatechin, quercetin, and naringenin, as well as the phenolic aldehyde vanillin. The C. polyantha infusions showed scavenging activity of DPPH• and ABTS•+ radicals as well as relevant antioxidant capacity, which was dependent on tea preparation conditions. A total of 46 volatile organic compounds (VOCs) were detected from the leaves and flowers of C. polyantha, while in the control group, a total of 30 VOCs were identified. Differences in consumer acceptability of C. polyantha infusions prepared at different conditions were observed. This research highlights the importance of linking sensory and chemical data to obtain the best sensorial quality and the optimal nutraceutical properties in C. polyantha infusions.