Impact of drying processes on volatilome and bioactive compounds in Damask and Centifolia moss roses and recovering of condensed waters

The importance of roses in the cosmetic, pharmaceutical and food sectors relies on their aromatic and volatile compounds. However, rose fresh flowers rapidly degrade, losing their phytochemical characteristics and fragrance. The composition of volatile organic compounds (VOCs) and the antioxidant activity of three roses, i.e., one Damask rose (Rosa × damascena Mill.), and two Centifolia roses, namely Moss rose (Rosa × centifolia f. muscosa (Ait.) C.K.Schneid.) and Valle Scrivia moss rose landrace, were assessed in fresh flowers and in dried flowers obtained through hot-air drying (HAD) and heat-pump drying (HPD) methods, and in the condensed waters recovered from this latter. The three roses were rich in phenylethyl alcohol and terpenoids, although each one showed peculiar profiles. Hot-air drying gave better results for the Moss and Valle Scrivia roses, better preserving monoterpenes and phenylpropanoids, while heat-pump drying gave better results for Damask rose, better preserving the phenyl derivatives and monoterpenes. This drying method also allowed the recovering of rose waters, which displayed interesting aroma compounds, such as the phenylethyl alcohol, making them suitable for food and cosmetic applications. This study provides the first genotype-specific evaluation of drying methods for damask and moss roses, establishing a basis for targeted post-harvest processing.