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This work evaluated the effect of two commercial pectolytic enzymes on some oenological parameters before and after enzymatic treatments with pre-fermentative dynamic maceration at room temperature for three hours. The study was conducted on an industrial scale using musts from sun-dried grapes of the Pedro Ximenez variety. Statistical analysis and sensory rating showed that the resulting wines varied significantly in total soluble solids (ºBrix) and in the final sensorial controls. On the other hand, the enzyme treatment had no effect on the content of total polyphenols (TPI) and other chemical characteristics of the obtained musts. A higher qualitative level was observed with regard to aroma and gustative quality compared to the control. The results also demonstrate that total juice yield improved after enzyme addition together with dynamic maceration.

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The growth conditions and ochratoxin A (OTA) production of Aspergillus strains were studied in aniseed (Pimpinella anisum L.)-based media. The results showed that methanol/NaHCO3 (50:50, v/v) mixture for extraction and competitive direct ELISA analytical method are capable of detecting low OTA concentrations in this raw material, which were confirmed by HPLC with fluorescence detection (R (2) = 0.994). In aniseed meal extract agar artificially contaminated with selected fungi, the higher OTA values obtained were 283.8 ± 28.1 μg L(-1) for A. carbonarius and between 1.7 ± 0.1 μg L(-1) and 16.5 ± 12.8 μg L(-1) for A. steynii strains. While the optimal conditions of growth for A. carbonarius and A. steynii are 28°C and 0.98 a w, the optimal production of OTA was observed at 0.99 a w for both A. carbonarius and A. steynii but at 22°C and 28°C, respectively. Except in one sample, all the aniseed samples analysed were negative for OTA natural contamination. This study demonstrates that aniseed can be a matrix capable to contamination with OTA, at least produced by A. carbonarius and A. steynii strains, regardless of the antimicrobial properties of aniseed essential oil.