Effect of harvest time and storage conditions on almond kernel oil and sugar composition

Abstract

The effect of storage for 6 months at 5degreesC (80% RH) versus 20degreesC (60% RH) of shelled versus in-shell almonds was studied on early versus late harvested nuts from 'Ferragnes' and 'Texas' trees. Kernel quality characteristics, oil composition and sugar composition were determined initially and after 6 months of storage. Early harvested almonds had similar kernel weight to but higher moisture content than late harvested almonds after 6 months of storage. Early harvested almonds also had similar oil quality (based on ultraviolet absorption coefficient measurements) and oil composition but lower sugar content and modified sugar composition compared with late harvested almonds. Storage of shelled almonds resulted in kernels with higher oil content, better oil quality, similar oil composition, similar sugar content and some modifications in sugar composition compared with in-shell stored almonds. Finally, storage for 6 months at either 5 or 20degreesC resulted in lower moisture content, higher oil content, similar oil quality and composition, similar sugar content and some modifications in sugar composition compared with freshly harvested almonds. Almonds stored at 5degreesC retained higher kernel weight and moisture content than almonds stored at 20degreesC. (C) 2003 Society of Chemical Industry.