Project Number: 5320-43000-014-17
Project Type: Trust

Start Date: Jun 25, 2007
End Date: Dec 26, 2008

Objective:
The objectives are to identify and quantify phytochemical compounds (tocopherols, tocotrienols, phytosterols, and phenolics) in macadamia cultivars and establish whether these compounds enhance the oxidative stability of dried and roasted kernels.

Approach:
Macadamia nuts of seven cultivars will be collected from different locations on the island of Hawaii. Nuts will be dried to a kernel moisture of 1.5% and roasted at 125'C for 20 minutes. The total oil content for each kernel sample will be measured using an Ankom fat extractor. Total antioxidant activity will be determined for the oils using a chemiluminescent system. Oxidative stability of the oils will be evaluated using a Rancimat instrument, which measures the rate of oxidation under accelerated conditions. The total phenolic content will be measured using the Folin-Ciocalteu method. Oils will be extracted and saponified for tocopherol and phytosterol analyses. The tocopherol, tocotrienol, and phytosterol contents of the extracted oil will be quantified using high pressure liquid chromatography. Correlations between phytochemical contents (tocopherol, tocotrienol, phytosterols, and phenolics) and total antioxidant activity and oxidative stability will be determined for dried and roasted samples of each cultivar. Documents Trust Agreement with State of Hawaii Department of Agriculture (HDOA). Log 32469.