Influence of harvest date on volatile and sensory profile of vine leaves infusions from two Portuguese red grape varieties

¹ Polytechnic Institute of Viseu (CI&DETS), Agrarian Higher School, Estrada de Nelas, Quinta da Alagoa, Ranhados, 3500–606 Viseu, Portugal
² CQ-VR, Chemistry Research Centre, University of Trás-os-Montes and Alto Douro, School of Life Science and Environment, Chemistry Department, 5001–801 Vila Real, Portugal
³ CQ-VR, Chemistry Research Centre, University of Trás-os-Montes and Alto Douro, School of Life Science and Environment, Biology and Environment Department, Edifício de Enologia, 5001–801 Vila Real, Portugal

^a e-mail: antoniojordao@esav.ipv.pt

Abstract

The main object of the present study was to investigate the volatile composition and sensorial profile of vine leaves infusions prepared from vine leaves collected 30 and 60 days after grape harvest from two Portuguese red grape varieties (Touriga Nacional and Tinta Roriz). Twelve volatile compounds were detected in vine leaves infusions (6-methyl-5-hepten-2-one, 1-undecene, Z-citral, cedrenol, DL-limonene, 2,4-hexadien-2-ol, benzaldehyde, heptane-1,2,4,6-tetraene, cyclohexene 1-methyl-4-(1-methylethyl), 1,6-octadien-3-ol, 3,7-dimethyl, 5,9-undecadien-2-one-6,10-dimethyl-(5E) and α-cedrol). In addition, it was observed that the volatile compounds present in vine leaves infusions were dependent on the harvest time, with significantly major volatile content in vine leaves collected after 30 days of harvesting. Thus, it was more important the harvesting date for the volatile profile of vine leaves infusion than the vine leave grape cultivar. Similar tendency was also obtained for the sensory profile, with significant differences for astringency and aroma intensity attributes of vine leaves infusions according to the harvesting date.