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Some aromatic plants such as Thymbra capitata, Origanum vulgare, and Calamintha baetica are used in some Portuguese traditional meat dishes, particularly in rabbit meat, tomato salads, fish food, escargot, and olives. In the present work, the antioxidant ability of the essential oils extracted from T. capitata, O. vulgare, C. baetica, and Th. mastichina cultivated in a field of the Regional Direction of Agriculture of Algarve (Portugal) was studied. The oils, extracted by hydrodistillation, were analysed by gas chromatography and gaschromatography coupled to mass spectrometry. The antioxidant activity was determined using a modified thiobarbituric acid-reactive substances (TBARS) method, measuring the scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method, determining the reducing power method, and monitoring the chelating effect on ferrous ions method. The results showed that the oils from O. vulgare and T. capitata had practically the same capacity of preventing the lipid oxidation of those of BHT and BHA. T. capitata oil was the most effective for the scavenging effect on DPPH as any capacity for this effect was practically absent in the oils of Th. mastichina and C. baetica. These results can be explained by the relative high concentrations of phenol compounds in those plants. The essential oil isolated from C. baetica possessed the best ability of chelating ferrous ions, something practically inexistent in the remaining other plant samples and the BHT and BHA. The reducing power of the essential oils was much lower than those observed for the synthetic antioxidants, nevertheless among the oils, those from O. vulgare and T. capitata were the most effective. The chelating effect of the C. baetica oil can be used as a synergistic antioxidant, that is, this oil can be used together with a phenolic antioxidant in the food product, but at lower levels.

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.

Summary This work reports on the preparation of new aromatic pomegranate liquors by maceration of pomegranate juice and arils in Arbutus unedo L. distillate. The volatile, anthocyanin and ellagitannin profiles were monitored after each step. Aromatic compounds of pomegranates, such as limonene, 1‐hexenol and trans‐caryophyllene, were detected in trace levels and showed little contribution to the liquor aroma. The main volatiles of the liquors, namely isobutanol, isopentanols, vitispiranes and volatile esters, are given by the fruit distillate. The anthocyanin contents of the pomegranate juice were around 135 mg L−1 but decreased to about 5% of this value in the final liquors. Anthocyanin diglucoside compounds showed higher stability than their monoglucoside analogs. Punicalagins and punicalins showed contents between 80 and 135 mg L−1, depending on the used starting pomegranate material. These ellagitannins account for 60% of the total polyphenols. The procedure can be used to prepare aromatic pomegranate liquors with high polyphenol content.