Água-mel (honey–water) is a typical honey-based product produced by the Portuguese beekeepers, particularly in southern Portugal. Água-mel was characterized by mineral content and volatiles contents. Mineral content evaluation was performed based on a random sampling of 14 samples from a total of 16 samples provided by local producers. Mineral content showed that potassium predominated in água-mel samples (1270–4105 mg/kg). The concentration of aluminium in one sample was tenfold higher (5.8 mg/kg) than in the remaining samples (0.3–0.6 mg/kg). Água-mel volatiles were isolated by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) from a subset of eight samples. Cluster analysis showed two poorly correlated clusters (S cₒᵣᵣ < 0.3). Cluster I only sample was dominated by trans-β-ocimene (19 %), γ-terpinene (15 %) and 2-furfural (9 %). Cluster II that included the remaining seven samples showed two moderately correlated subclusters (S cₒᵣᵣ < 0.5). The six samples with high correlation from subcluster IIa were dominated by 2-furfural (18–41 %) and benzene acetaldehyde (12–39 %). n-Nonadecane (14 %), n-heneicosane and 2-furfural (both 13 %) were the main components of subcluster IIb sample. Although the presence of some volatile compounds can help in the correlation between água-mel and honey botanical source, the final product varies largely according to the preparation process even for the same producer, in different years. Água-mel detailed characterization may assist in bringing added value to this typical Portuguese honey-based product.

[ES] El riego es utilizado para paliar el déficit hídrico, sin embargo, dicha irrigación a largo plazo puede producir la salinidad del suelo. Una concentración de sal en el agua de riego inhibe el crecimiento de la planta de dos formas, la primera al limitar la absorción de agua, provocando un efecto osmótico o déficit hídrico que se origina al aumentar la concentración de solutos en el suelo; y la segunda, al condicionar la absorción iónica produciendo un daño en las células provocando un estrés iónico. Por consiguiente, con el paso del tiempo las raíces de la vid se verán enfrentadas a un aumento de la salinidad y un déficit hídrico que frenará su crecimiento dificultando el rendimiento de la vid y, por tanto, la sostenibilidad del viñedo. La reutilización del agua puede considerarse como una alternativa rentable en la agricultura. Esta práctica consiste en mezclar ¿agua de buena calidad¿ con una de otras características, un poco inferiores como puede ser que tengan un porcentaje de sales elevado. El objetivo del trabajo es estudiar el efecto de la utilización de aguas no convencionales provenientes de la depuración de los vertidos municipales para reducir el déficit hídrico del suelo al que se ven sometidos los viñedos en secano, sobre la composición aromática de los vinos elaborados a partir de estas uvas procedentes de los distintos protocolos de riego. | [EN] The irrigation is used to palliate the water deficit, but this irrigation in the long term could result in an excessive soil salinity. An overconcentration of salt in the irrigation water inhibits the plant to grow in two ways: firstly by limiting the absorption of water, causing an osmotic effect or water deficit that originates from increasing the concentration of solutes in the soil; and the second by limiting the ionic absorption which damages the cells and results in an ionic stress. Consequently, in the long run, the roots of the vine will face an increase on their salinity levels and a water deficit that will eventually slow down and reduce its growth, worsening the vine's performance and therefore the sustainability of the vineyard. Reusing water can be considered as a profitable alternative in agriculture. This practice consists in mixing "high quality water" with another one of worse characteristics, could be for example with a higher salts percentage. The objective of the dissertation is to study the effect of the use of unconventional waters from the purification of municipal discharges to reduce the water deficit of the soil from which dry vineyards are affected and on the wines aromatic composition made out of these grapes from the different irrigation protocols. | Sánchez Giménez, J. (2022). Efectos de la calidad del agua de riego usado en el viñedo sobre la composición aromática de vinos de la variedad Monastrell. Universitat Politècnica de València. http://hdl.handle.net/10251/188514