Transformation of Anthocyanins During Preparation of Rose Wine by Following a Pre-fermentative Cold Maceration Process Ludovina Galego 1,2(&) and José P. Da Silva 3 1 Instituto Superior de Engenharia, Universidade do Algarve, Campus da Penha, 8005-139 Faro, Portugal lgalego@ualg.pt 2 MeditBio, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal 3 CCMAR - Centro de Ciências do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal jpsilva@ualg.pt Abstract. Castelão is a Portuguese native grape variety commonly used in the south of the country to produce white, rose and red wines. This work reports a study on the transformation of anthocyanins of Castelão grape variety during the preparation of a rose wine. The grapes were collect at Quinta dos Vales (Estômbar – Lagoa, Algarve) vineyards. The rose wine was prepared at Quinta dos Vales by following a pre-fermentative maceration process at 4 °C during 5 h. The anthocyanins were analysed in grape’s skin and in prepared wine by LC-DAD-MS. The total phenol contents of skin extracts and wine were made by following the Folin-Ciocalteu method. The quantification of individual antho- cyanins was performed by HPLC-DAD using traces obtained at 520 nm and malvidin-3-O-glycoside as standard. The anthocyanins identified in the grape skin were: delphinidin-3-O-glycoside, petunidin-3-O-glycoside, peonidin-3-O- glycoside, malvidin-3-O-glycoside, malvidin-3-O-acetylglycoside and malvidin- 3-O-coumarinoglycoside. The most abundant anthocyanin in the skin is malvidin-3-O-glycoside, (1.1 mg/g of dry skin). Its content relatively decreases during wine preparation. The major anthocyanin in wine is malvidin-3-O-cou- maroylglucoside (12.7 mg/L). Although the same anthocyanins were identified in grapes and wine, the results show a significant effect of the maceration and fermentation processes on the anthocyanin profiles. Keywords: Castelão grapes Á Rose wine Á Identification of anthocyanins Á LC-DAD-MS 1 Introduction The wine production in Algarve dates back to Roman times [1]. It had a great devel- opment with the Portuguese discoveries. However, after the mid XX century, a strong decline was observed. This has been associated with the increase of tourism that changed the vineyard areas from the coastal regions to the countryside. In the beginning © Springer Nature Switzerland AG 2020 J. Monteiro et al. (Eds.): INCREaSE 2019, pp. 246–251, 2020. https://doi.org/10.1007/978-3-030-30938-1_20