Quality of lipid fraction during Spanish-style table olives processing of Sigoise and Azzeradj cultivars

33 Páginas.-- 6 Tablas.-- 2 FigurasThis work aimed to study the effect of different steps of Spanish-style processing (raw olives, lye treatment, washing, and fermentation) on the oil quality index (Acidity, peroxide value (PV) and extinction coefficient UV at 232 nm and 270), fatty acids, phenols, tocopherols, hexanal and nonanal compounds, and antioxidant activity of the lipid fraction of green Sigoise and Azzeradj cultivar. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used to discriminate the samples according to cultivars and elaboration phases. Most of the variance of the quality parameters and fatty acids was due to cultivars and less for processing. After processing, a substantial loss in the total and individual phenolic compounds was recorded (79.25% and 67.58% for Azzeradj and Sigoise, respectively), but the most significant reduction occurred at lye treatment and washing step rather than the fermentation. Tocopherols were less affected than the phenolic compounds. The antioxidant activity against DPPH radicals of the total lipid fraction of olives was less affected than that of its methanolic extract alone.The authors want to thank the Algerian Ministry of High Education and Scientific Research for sponsoring this work. The authors are grateful to the staff of ITAFV (Institut d’Arboriculture Fruitière et de la Vigne) Takerietz (Bejaia, Algeria) and the company of KHODJA & CO Seddouk (Bejaia, Algeria) for providing the samples.Peer reviewe

Chemical parameters and antioxidant activity of turning color natural-style table olives of the Sigoise cultivar Parámetros químicos y actividad antioxidante de aceitunas de mesa al estilo natural de color cambiante de la variedad Sigoise

11 Páginas.-- 3 Tablas.-- 2 FigurasA chemical characterization of turning color table olives of the Sigoise variety was made through their processing as natural-style. Polyphenols, sugars, tocopherols, fatty acids, and antioxidant activity in the olives were monitored throughout the elaboration process. Oleuropein, salidroside, hydroxytyrosol 4-glucoside, rutin, ligustroside and verbascoside showed a decrease of 16.90-83.34%, while hydroxytyrosol increased during the first months of brining. Glucose was consumed by 90% due to the metabolism of the fermentative microbiota. The tocopherol content remained stable during the process and only the α-tocopherol decreased. The fatty acids were not affected. The loss in antioxidant compounds resulted in a decrease in the percentage of DPPH radical inhibition from 75.91% in the raw fruit to 44.20% after 150 days of brining. Therefore, the turning color natural table olives of the Sigoise variety are a good source of bioactive compounds.La caracterización química de las aceitunas en salmuera de color cambiante de la variedad Sigoise se ha estudiado durante el proceso de elaboración, en particular la concentración de fenoles, azúcares, tocoferoles, ácidos grasos y la actividad antioxidante. La concentración de oleuropeína, salidrósido, hidroxitirosol 4-glucósido, rutina, ligustrósido y verbascósido disminuyó un 16,90-83,34% durante el primer mes en salmuera. El 90% de la glucosa fue consumida debido al metabolismo de la microbiota fermentativa. El contenido en tocoferoles se mantuvo constante durante el proceso y solo disminuyó el α-tocoferol. Los ácidos grasos no se vieron afectados. La pérdida de actividad antioxidante se tradujo en una disminución del porcentaje de inhibición del radical DPPH de un 75,91% del fruto fresco a 44,20% después de 150 días en salmuera. A pesar de todo, la aceituna color cambiante de la variedad Sigoise en salmuera es una buena fuente de compuestos bioactivos.We want to thank the Algerian Ministry of Higher Education and Scientific Research for sponsoring this work. The authors are grateful to the staff of the company KHODJA & CO Seddouk (Bejaia, Algeria) for providing the samples. This work was also supported by the Spanish Government (Project RTI2018-093994-J-I00, AEI/FEDER, UE and Ramón y Cajal Programme RyC2018-024752-I).Peer reviewe

Chemical characterisation and antioxidant activity of Spanish-style green olives of the Azerradj and Sigoise cultivars

9 Pa´ginas.-- 4 Tablas.-- 1 FiguraThe chemical composition and the antioxidant activity of two Algerian olive cultivars (Azerradj and Sigoise) elaborated as Spanish-style table olives were studied. The pH and the titratable acidity followed the same general pattern during the fermentation process for both cultivars but Sigoise reached higher titratable acidity and lower pH values. Both varieties exhibited a high total phenolic content of 5382.7and 6754.3mgGAE/100g and a total flavonoid of 424.6 and 568.5mgRE/100g for the raw fruit of Azerradj and Sigoise, respectively, but decreased a 55.2 - 66.26% after 120 days of fermentation. The alpha-tocopherol decreased along the elaboration process while the beta and gamma-tocopherols remained constant. The losses of polyphenols and tocopherols were well correlated with the dropping of DPPH antiradical and the ferrous chelating activity during the processing. The fatty acid content was less affected by the processing than the other components without significant changes. The results of this work revealed that Sigoise cultivar, the most used, showed better nutritional values and suitability to the Spanish-style processing than Azerradj variety. However, table olives from both varieties can still be considered as a functional food with high amounts of bioactive compounds involved in health benefits.The authors wish to thank the Algerian Ministry of Higher Education and Scientific Research for sponsoring this work. The authors are grateful to the staff of the KHODJA & CO Company, Seddouk (Bejaia, Algeria), for providing the samples.Peer reviewe