Original article Preparation of novel distinct highly aromatic liquors using fruit distillates Ludovina R. Galego, 1 * Jose ´ P. Da Silva, 2 Valentim R. Almeida, 3 Maria R. Bronze 3 & Luı´s V. Boas 3 1 Instituto Superior de Engenharia, Universidade do Algarve, Campus da Penha, 8005-139 Faro, Portugal 2 Faculdade de Cieˆncias e Tecnologia, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal 3 Instituto de Tecnologia Quı´mica e Biolo´gica, Quinta do Marqueˆs – Apt 127, 2780-505 Oeiras, Portugal (Received 28 May 2010; Accepted in revised form 7 September 2010) Summary This work describes the preparation of aromatised liquors using deodorised and concentrated fruit distillates. The raw spirits were improved by making a partial deodorisation, using activated charcoal, followed by concentration, using a distiller. The liquors were prepared by a maceration process. The procedure is exemplified using fig distillates to prepare myrtle berry liquors. The acidity, copper, polyphenol and anthocyanin indexes and volatile and anthocyanin profiles were monitored in each preparation step. The concentration process increased the ethanol proof to 75% v ⁄ v and decreased the acidity and the copper content. The partial deodorisation decreased the levels of high molecular weight volatiles, while the content of lower molecular weight compounds that contribute to flavour was maintained. Delphinidin-3-O-glucoside, cyanidin-3-O-glucoside, petunidin-3-O-glucoside and malvidin-3-O-glucoside were the major anthocyanins. Keywords Anthocyanins, food processing aspects, food processing chemistry, food quality, GC ⁄ MS, HPLC. Introduction The production of liquors usually consists in the introduction of colour-giving and aromatising sub- stances, derived from fruits or aromatic plants, into hydroalcoholic solutions, during a certain period of time (maceration) (Tho¨nges, 1994; Go´mez et al., 2009). The process also involves the addition of sweeteners (Euro- pean Union EC, Regulation 110 ⁄ 2008) and ends with a minimum maturation period of 3 months. Rectified raw spirits are usually used in the industrial preparation of liquors (Plutowska & Wardencki, 2008). These pure hydroalcohol solutions can be used to prepare liquors, but volatile compounds, which might contribute to the aroma of the distillate or of the liquor, are not present (Lilly et al., 2006; Leo´n-Rodrı´gues et al., 2008; Pluto- wska & Wardencki, 2008; Go´mez et al., 2009; Tesˇevic´ et al., 2009; Garcı´a-Martı´n et al., 2010). Among the several fruit distillates available in Med- iterranean climate countries, fig distillates are one of the oldest (Ayed et al., 1992). Depending on the quality of the raw products and the hygienic and fermentative conditions in the distillery, some fig distillates might show some problems common to other raw distillates, namely high acidity (Versini et al., 1995; Galego, 2006) and high copper content (Galego, 2006; Caldas et al., 2009; Penteado & Masini, 2009), the latter associated with the traditional use of copper distillers. The max- imum permitted level of copper in Brazilian sugarcane spirits is 5.00 mg L )1 (Neves et al., 2007), while in Portugal, for strawberry tree (Arbutus unedo L.) distil- lates, the maximum level is 15.0 mg L )1 (Decreto-Lei 238 ⁄ 2000 de 26 de Setembro). Distillates with acidity levels of 0.08–0.1 g L )1 of ethanol (8–10 mg per 100 mL P.A) are considered of poor quality (Kosowski & Czupryn´ski, 2006). These defects make the spirit unap- preciated, even when used to produce liquors. Charcoal filters have been reported to decrease the acid content of Brazilian ‘cachac¸a’. The use of these filters also reduces the copper content and imposes small changes in the volatiles profile (Souza et al., 2009). Charcoal filters are also used in the rectification of vodka (Regulation EEC 1576 ⁄ 1989; Lachenmeier et al., 2003). The use of charcoal filters have therefore potential to improve the lower quality raw distillates. The presence of high molecular weight esters and ethyl acetate, which are associated with unpleasant odours, is sometimes related to the excess of acidity (Herna´ndez-Go´ mez et al., 2005). However, when at low levels (<120 mg per 100 mL of raw distillate, evaluated as ethyl acetate), they contribute to a pleasant flavour (Herna´ndez-Go´ mez et al., 2005; Garcı´a-Llobodanin et al., 2007, 2008). To prepare high-quality liquors using *Correspondent: Fax: 351 289888405; e-mail: lgalego@ualg.pt International Journal of Food Science and Technology 2011, 46, 67–73 67 doi:10.1111/j.1365-2621.2010.02452.x Ó 2010 The Authors. International Journal of Food Science and Technology Ó 2010 Institute of Food Science and Technology