The effect of water, brine and ethanol flotation on the quality and shelf life of macadamia kernels. 2. Kernel pieces

Abstract

Effects of water, brine and ethanol flotation on the shelf life of raw macadamia kernel pieces were investigated. Macadamia kernel pieces were immersed in water (sp. gr. 1.00 g/cm3), brine (sp. gr. 1.02 g/cm3) or ethanol solution (sp. gr. 0.97 g/cm3) for 30 or 60 s, then re-dried to <1.5% moisture (wet basis) and stored under vacuum for 0, 4 and 12 months. Flotation in water had no effect on the quality or shelf life of kernel pieces over 12 months storage, when measured by sensory analysis of the kernels and chemical analysis of the kernel oil. Immersion in a salt solution caused unacceptable changes in quality during storage which increased as storage time increased. Flotation in dilute ethanol also caused unacceptable quality changes during storage. It is suggested that flotation of macadamia kernel pieces in water can be recommended for commercial operations.