Characterization of virgin walnut oils and their residual cakes produced from different varieties.
Food Res Int
; 108: 396-404, 2018 06.
Article
em En
| MEDLINE
| ID: mdl-29735072
ABSTRACT
This study addresses the composition and properties of different walnut varieties (Chandler, Hartley and Lara), in particular their virgin oils and residual cakes obtained by screw pressing employing different cultivars. Among nuts, walnut (Juglans regia L.) exhibits interesting nutritional value, mainly due to their high content in linoleic acid, phenolic and tocopherol compounds, which show antioxidant and other healthy properties. Valuable results related to fatty acid profile and minor components were observed. Virgin walnut oil is a rich source in linoleic acid (60-62%) and γ-tocopherol (517-554â¯mg/kg). Moreover, walnuts show a very high content in total phenolic compounds (10,045-12,474â¯mg/kg; as gallic acid), which contribute to a great antioxidant activity (105-170â¯mmol/kg for DPPH, and 260-393â¯mmol/kg for ORAC), being the hydrolysable tannins (2132-4204â¯mg/kg) and flavanols (796-2433â¯mg/kg) their main phenolic groups. Aldehydes account for the highest contribution to aromatic volatiles in virgin walnut oil (about 35% of total). As expected, polar phenolic compounds concentrate in the residual cake, after the separation of the oily phase, reaching a content of up to 19,869â¯mg/kg, leading to potential added value and applications as source of bioactive compounds to this by-product.
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Base de dados:
MEDLINE
Assunto principal:
Óleos de Plantas
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Juglans
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Análise de Alimentos
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Manipulação de Alimentos
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Nozes
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article