Linalool is a monoterpene, which exhibits floral and spicy
aromas as well as a variety of pharmacological effects,
including antioxidant, anti-inflammatory, and cardiovascular.
Wine flavor is highly dependent on the chemical compounds
of berries. The objective of this study was to evaluate the
concentration of volatile compounds, especially linalool, in
grapes (
Vitis vinifera
L.) ‘Muscat of Alexandria’ grown under
different cluster light exposure. Four defoliation treatments
were applied at veraison, and changed the light environment
at the fruit zone. Severe defoliation (T1): leaves were
manually removed from the 1
st to the 8
th node of each shoot,
partial defoliation (T2): leaves were manually removed from
the 1
st to the 4
th, semi-shaded clusters (T3): un-trimmed vines
were covered with an 80% shade netting; and (T4) control
treatment with non-intervention during season 2014-2015.
Free terpenes were extracted using headspace solid-phase
microextraction (HS-SPME), and the concentration of volatile
compounds was determined using gas chromatography
coupled to a flame ionization detector (GC-FID). The study
was conducted in two different locations of the Itata Valley
in Chile. Linalool concentration was more prevalent in
treatments with higher cluster exposure. The treatment with
the highest defoliation showed a linalool concentration 40%
higher than the control treatment. Higher levels of defoliation
in grapevines grown under a traditional farming system
result in an increased concentration of volatiles compounds,
particularly monoterpenes, where Cerro Verde and Pinihue
reached linalool concentrations of 19.1 and 21.7 μg L
-1,
respectively. These results revealed important differences in
the behavior of the synthesis of linalool.
