Macadamia nut—Specialty Crop Profile

Nearly mature macadamia nuts on the tree.

Dried kernels are roasted and manufactured by processors and industrial users into a wide number of products featur­ing whole or half kernels that are unsalted, dusted with fine­ly ground confectionery salt, or flavored. Chocolate-coated kernels have become a major product. Second grade and broken kernels (pieces) are used in confectionery products such as brittles and candies or diced for use as garnishes, ice cream, sherbets, cakes, and pastries. Kernels are also milled into a premium nut butter and the oil is extracted for use in food and cosmetics.

Home processing of macadamia can be accomplished to produce an acceptable product.

1. Remove the outer husk of freshly fallen nuts soon after harvesting.

2. Air-dry in-shell nuts for 2–3 weeks on screens by spread­ing them in layers not more than two nuts thick, in the shade where there is good air circulation. Nuts are suffi­ciently dried when they rattle and kernels are loosened from the shell.

3. Crack nuts with a vise or cracker specially designed for cracking macadamia. Separate shells from the kernels, re­move discolored and pest-damaged kernels, and begin dry­ing.

4. Use a home food dehydrator in which the drying temper­ature can be well controlled. Dry kernels slowly at 38°C, for about 2 days, increase temperature to 52°C for 2–3 days and to 60°C for 2 days. It’s difficult to predict length of the drying process. Check the texture of kernels periodically during the final drying by biting into a kernel. Completely dry kernels are very crisp. The drying process should be slow; if the tem­perature is too high, kernels can dry unevenly, change color, or have brown centers when roasted. After drying, kernels are ready for roasting. They can be stored in tightly sealed jars for a short while, but for longer storage, they should be frozen and thawed in a sealed jar.

5. To roast macadamia nuts, place dried kernels in an oven at 135°C for 20–30 minutes. Wire-screen trays are best for the roasting process. Check the color as roasting progresses, and roast to the desired golden color.

6. For salted macadamia nuts, coat roasted kernels lightly with a small quantity of salad oil. Apply the desired amount of powdered salt and shake to distribute the salt evenly. Place nuts in a jar to protect them from picking up moisture. If they are not to be consumed soon, they may be kept fro­zen for up to a year.

Original source of this article

This article is excerpted by permission of the publisher from

Nagao, M.A. 2011. Macadamia Nut (Macadamia integrifolia and M. tetraphylla). In: Elevitch, C.R. (ed.). Specialty Crops for Pacific Island Agroforestry. Permanent Agriculture Resources (PAR), Holualoa, Hawai‘i. © Permanent Agriculture Resources.