Macadamia (genus)
Macadamia is a genus of tropical evergreen trees known for producing edible kernels commonly referred to as macadamia nuts. Native to the northeastern coast of Australia, these trees have been integral to local Aboriginal cultures for centuries, who harvested the nuts, known as Baupal, Jindill, or Boombera, for special meals and ceremonial purposes. Despite being termed "nuts," they do not meet the botanical criteria for nuts, as their hard outer shell is not fused to the seed inside. The macadamia nut is named after Scottish chemist John Macadam, who contributed to its scientific understanding in the 19th century.
Macadamia trees thrive in warm climates and can grow up to 40 feet tall, bearing large leaves and clusters of white flowers. The nuts are typically harvested when ripe, with most varieties dropping to the ground, whereas others require handpicking. Not only are macadamia nuts enjoyed worldwide for their rich taste, but they also offer health benefits due to their high content of monounsaturated fatty acids and essential nutrients. Although calorie-dense, they can be a heart-healthy snack when consumed in moderation. Today, macadamia cultivation has expanded beyond Australia to regions like Hawaii, New Zealand, and parts of Central and South America.
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Macadamia (genus)
Macadamia is the name of a genus of tropical evergreen trees and the name of the edible kernels these trees can produce. Native to Australia, trees from this genus were later transported to New Zealand and Hawaii, where they were used to help in reforestation efforts and eventually became important food crops. Today, people around the world eat macadamia nuts. The nuts contain essential nutrients that are beneficial to heart health when eaten in moderation.
Background
Although they are often called nuts, the product of the macadamia tree are not considered nuts by botanists. The botanical definition of a nut refers to a seed that is fused to its hard shell, such as acorns, hazelnuts, and chestnuts. The macadamia nut does have a hard outer shell, but it is not fused to it. Still, in the culinary world, macadamias are often considered nuts because of the way they are prepared and consumed.
The macadamia nut is named for Scottish-born chemist John Macadam, but their history dates back long before Macadam helped describe them during the nineteenth century. Trees of the Macadamia genus are native to the northeastern coast of Australia. For centuries, the Aboriginal people who lived in that area harvested nuts that they called Baupal, Jindill, or Boombera. The name Baupal came from an Aboriginal legend about a man named Baupal who was lost and hurt. Animals rescued him by bringing him what became known as macadamia nuts, which helped him survive. The Aboriginal people treated these nuts like a treasure, eating them only at special meals and saving them for use in important trades or as ceremonial gifts.
This may have been due to how difficult it was to get to the macadamia nut; the soft, sweet white kernel is hidden in a hard shell that is difficult to crack. To open the shell, Aboriginal women would hold a special grooved rock over the macadamia and then hit that rock with another rock. This allowed them to crack the shell and extract the soft kernel inside with minimal damage to the kernel.
Non-native people first came to know the trees in 1828, when English botanist and explorer Allan Cunningham first identified them. In the 1850s, German-born botanist Ferdinand von Mueller was working with Macadam to study the nuts. Von Mueller wrote some of the first formal scientific descriptions of the macadamia, while Macadam encouraged their propagation, which earned him the honor of having the genus of trees and the nut named after him. The first macadamia plantations were started in the late 1880s and 1890s. The macadamia nut remains the only major food crop that is native to Australia.
During the 1880s, new techniques to graft the trees and machine processing made macadamia nuts a commercially viable product. The nuts made their way to the European market, where they were known as bopple and kindal nuts, both variations of earlier Aboriginal names. Other names for the nuts included Queensland nuts, Mullumbimby nuts, bush nuts, and maroochi nuts.
The macadamia seeds were taken to Hawaii around 1881, when William Purvis, the manager of a sugar company, planted some on a sugar plantation. The trees originally served as windbreaks to protect the sugarcane. However, Hawaiian residents soon came to enjoy macadamia nuts. By 1921, the trees were being grown commercially on the Hawaiian Islands. By the 1930s, macadamia nuts and products made from them, such as candied nuts, were becoming an important commercial enterprise in Hawaii.
Macadamia trees have since been grown in parts of Africa, Israel, Costa Rica, Guatemala, Mexico, Brazil, and Florida. In addition, there are significant commercial macadamia operations in New Zealand. While the varieties of macadamia trees grown in Australia, Hawaii, and many other areas drop their nuts when they are ripe, allowing for ground harvesting, the variety grown in New Zealand need to be handpicked.
Overview
Trees in the Macadamia genus produce the macadamia nut. The large, tropical evergreen trees grow in rainforests and similarly warm climates, where they can reach a height of thirty to forty feet (about nine to twelve meters). The trees have large leaves that range from eight to eleven inches (about twenty to twenty-eight centimeters) in length. The trees' white flowers form in clusters that are about six to twelve inches (about fifteen to thirty centimeters) in length.
Macadamia nuts grow encased in a green husk until they are ripe, at which time the husk splits to release the hard-shelled seed. Most macadamia trees drop their nuts when they are ready for harvest, but some require handpicking. The nuts can be eaten raw but are often roasted. They are about 80 percent fat, and they are sometimes used to make an edible oil because of this.
Although macadamia nuts contain a great deal of fat, they also contain monounsaturated fatty acids. These fatty acids, which are found in olive oil, are considered beneficial to the heart and circulatory system. Macadamias also contain a good quantity of fiber, which is important for healthy digestion, and trace minerals such as calcium, iron, copper, chromium, manganese, zinc, and magnesium. However, they do have a significant amount of calories—about two hundred per ounce. Therefore, experts recommend that people eat them only in small quantities.
Bibliography
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"Is a Macadamia Nut Really a Seed, or a Nut?" Arizona State University, askabiologist.asu.edu/questions/macadamia-nut-classification. Accessed 5 June 2017.
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Sweetman, Terri. "Colourful History of Our Delicious and Native Macadamia Nuts Not Hard to Crack." Courier Mail, 10 Aug. 2013, www.couriermail.com.au/news/queensland/colourful-history-of-our-delicious-and-native-macadamia-nuts-not-hard-to-crack/news-story/99a22c6b23e512caf3764b867bf2f59f. Accessed 5 June 2017.
Yang, Flora. "History of the Macadamia." MacNut, 30 Mar. 2015, www.macnut.co.nz/macadamia-info/history-of-the-macadamia/. Accessed 5 June 2017.