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During the industrial processing of almond fruits tons of almond skins are generated. Valorization of blanched almond skin wastes by recovering natural polyphenols using water, instead of organic solvents, for direct application of aqueous baths for dyeing of wool fabrics was studied in this work. The results shown that it was possible to recover polyphenols from almond skins and use them as a dye for wool fibres. Kinetic of extraction was modelled by using diffusion based Chrastil model and Peleg’s empirical model obtaining excellent fit in both cases (R2>0.96). The amount of polyphenol extracted was enough to achieve correct direct dyeing with excellent washing, rubbing and perspiration fastness although the obtained shades are dull. Nevertheless, it was possible to achieve a better coloration by using ion(II) sulphate as mordant resulting in dyeings with reasonable good washing and rubbing fastness, Postprint (author's final draft)

[EN] Reinforced poly(e-caprolactone) (PCL)/almond skin (AS) biocomposites were prepared by extrusion and injection moulding at different AS contents (0, 10, 20, 30 wt%) in order to revalorize this agricultural residue. AS particles were characterized by field emission scanning electron microscopy (FESEM), attenuated total reflectance infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis (TGA). Hemicelluloses were the first compound thermally degraded (263 +/- 2 degrees C) followed by cellulose (330 +/- 5 degrees C) and lignin (401 +/- 3 degrees C) with a remaining residue of 20% which was associated to the fibre content present in AS. Mechanical, morphological, thermal, and water absorption properties; and enzymatic degradation using Pseudomonas lipase were evaluated for the obtained biocomposites. A significant improvement in Young's modulus with a gain of 73% at 30 wt% AS loading was obtained compared to neat PCL An increase in Shore D hardness and decrease in elongation at break and impact energy were also observed with increasing AS content caused by the reinforcement effect. Lower DSC thermal enthalpies and higher crystallinity were obtained for the biocomposites. Some decrease in thermal stability and higher water absorption values were also found with AS addition. Finally, the presence of AS retarded the enzymatic degradation of PCL, showing neat PCL higher weight loss after 25 days of study followed by PCL with 10 wt% AS. (C) 2016 Elsevier Ltd. All rights reserved.

[EN] Reinforced poly(e-caprolactone) (PCL)/almond skin (AS) biocomposites were prepared by extrusion and injection moulding at different AS contents (0, 10, 20, 30 wt%) in order to revalorize this agricultural residue. AS particles were characterized by field emission scanning electron microscopy (FESEM), attenuated total reflectance infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis (TGA). Hemicelluloses were the first compound thermally degraded (263 +/- 2 degrees C) followed by cellulose (330 +/- 5 degrees C) and lignin (401 +/- 3 degrees C) with a remaining residue of 20% which was associated to the fibre content present in AS. Mechanical, morphological, thermal, and water absorption properties; and enzymatic degradation using Pseudomonas lipase were evaluated for the obtained biocomposites. A significant improvement in Young's modulus with a gain of 73% at 30 wt% AS loading was obtained compared to neat PCL An increase in Shore D hardness and decrease in elongation at break and impact energy were also observed with increasing AS content caused by the reinforcement effect. Lower DSC thermal enthalpies and higher crystallinity were obtained for the biocomposites. Some decrease in thermal stability and higher water absorption values were also found with AS addition. Finally, the presence of AS retarded the enzymatic degradation of PCL, showing neat PCL higher weight loss after 25 days of study followed by PCL with 10 wt% AS. (C) 2016 Elsevier Ltd. All rights reserved.

A microwave-assisted extraction (MAE) procedure to isolate phenolic compounds from almond skin byproducts was optimized. A three-level, three-factor Box–Behnken design was used to evaluate the effect of almond skin weight, microwave power, and irradiation time on total phenolic content (TPC) and antioxidant activity (DPPH). Almond skin weight was the most important parameter in the studied responses. The best extraction was achieved using 4 g, 60 s, 100 W, and 60 mL of 70% (v/v) ethanol. TPC, antioxidant activity (DPPH, FRAP), and chemical composition (HPLC-DAD-ESI-MS/MS) were determined by using the optimized method from seven different almond cultivars. Successful discrimination was obtained for all cultivars by using multivariate linear discriminant analysis (LDA), suggesting the influence of cultivar type on polyphenol content and antioxidant activity. The results show the potential of almond skin as a natural source of phenolics and the effectiveness of MAE for the reutilization of these byproducts.

A microwave-assisted extraction (MAE) procedure to isolate phenolic compounds from almond skin byproducts was optimized. A three-level, three-factor Box–Behnken design was used to evaluate the effect of almond skin weight, microwave power, and irradiation time on total phenolic content (TPC) and antioxidant activity (DPPH). Almond skin weight was the most important parameter in the studied responses. The best extraction was achieved using 4 g, 60 s, 100 W, and 60 mL of 70% (v/v) ethanol. TPC, antioxidant activity (DPPH, FRAP), and chemical composition (HPLC-DAD-ESI-MS/MS) were determined by using the optimized method from seven different almond cultivars. Successful discrimination was obtained for all cultivars by using multivariate linear discriminant analysis (LDA), suggesting the influence of cultivar type on polyphenol content and antioxidant activity. The results show the potential of almond skin as a natural source of phenolics and the effectiveness of MAE for the reutilization of these byproducts.