On the Origin of Banana Apples by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life
October 11th, 2008
The apple is thought to have originated in the mountains of Kazakhstan, and it “spread very early through the Middle East. It was known in the Mediterranean region by the time of the Greek epics, and the Romans introduced it to the rest of Europe” (On Food and Cooking, 354). The fruit figures into much cultural lore and founding myths, from Christianity to Norse Mythology to gravity, the governing force in our universe. As Henry David Thoreau wrote in his essay Wild Apples, “It is remarkable how closely the history of the apple tree is connected with that of man” and “The apple was early so important, and generally distributed, that its name traced to its root in many languages signifies fruit in general” (Thoreau, 140).
It seems like everyone has a childhood memory that revolves around apples. I remember weekend trips to the local orchard, where we’d pick our own Jonagolds, and then my mom would make the most delicious homemade applesauce. That sauce was a point of pride for me for years. I’d always attest to my mother’s excellence as a mom and homemaker by saying, “well, she makes her own applesauce and strawberry jam.” When I was talking to her earlier this week, she remembered an apple tree up on the Levi farm in Troupsburg, NY that produced apples that smelled and tasted exactly like bananas. Once ripe, they would last for a week before they began to rot.
The story of “banana apples” got me thinking. Beyond the obvious children’s book potential, the idea of an apple that smelled and tasted like a banana made me wonder about what determines an apple’s qualities, as well as different types of heirloom apples and the culture of apple cultivation.
The four main groups of apples–cider apples, dessert apples, cooking apples, and dual-purpose apples–have qualities that make them ideal for their respective purposes. Cider apples, which are pressed to make cider, “are high-acid fruits rich in astringent tannins, qualities that help control the alcoholic fermentation and clarify the liquid” (On Food and Cooking, 354). The second main division, between dessert and cooking apples, depends on pH and sugar. While dessert apples have a pH around 3.4 and are ~15% sugar, cooking apples have a pH around 3 and are ~12% sugar. Dessert apples (meant to be eaten out of hand) have a sweet-tart balance and can easily turn to mush when heat is applied, whereas cooking apples are much firmer and tarter, and withstand heat much better. Dual-purpose apples, which do well eaten out of hand or cooked, are becoming increasingly popular. Dual-purpose apples “are usually at their best for cooking when young and tart, best for eating when older and more mellow” (On Food and Cooking, 355).
Now after laying this groundwork, back to the mystery of the banana apple. The apple’s sugar/acid ratio is, on average, 13. The banana’s sugar/acid ratio, however, is much higher at 60. The banana is significantly sweeter than the apple, and I would guess that the banana apple has a much higher sugar content than the average apple.
This higher sugar content may contribute to the short shelf-life of both bananas and banana apples. Mature fruits feed off their stored energy (in the form of starch) and deteriorate (rot) when they run out of resources. This process is aided by bacteria, fungus, and microbes. Although fruits usually have enough acid to slow bacteria, I would guess that the very high sugar-to-acid ratio in bananas and banana apples allows bacteria to act quicker.
“The final stage of fruit development is ripening, a drastic change in the life of the fruit that leads to its death. It consists of several simultaneous events. Starch and acid levels decrease, and sugars increase” (On Food and Cooking, 351).
Since bananas and (presumably) banana apples have a high sugar content at the expense of starch reserves, there is not a large enough amount of starch to support a long mature/ripe stage. Respiration (”…the process by which plants take in oxygen and give out carbon dioxide” (Prevention of post-harvest food losses: Fruits, vegetables and root crops. Food and Agricultural Organization of the United Nations. Rome, 1989)) is cut short by lack of resources, and the fruit dies.
The distinctive scent of banana apples is likely explained by the same components that determine a banana’s aroma: “amyl acetate and other esters, and green, floral, and clove (eugenol) notes” (On Food and Cooking, 378). An ester is an acid and an alcohol, and “fruits have enzymes that join these basic cell materials into aromatic esters” (On Food and Cooking, 355). Although the predominant ester in apples is ethyl acetate (ethyl alcohol and acetic acid), an apple would smell like bananas if it instead had isoamyl acetate (isoamyl alcohol and acetic acid) as its primary ester.
The combination of isoamyl acetate and higher sugar content could make an apple smell and taste like a banana. Of course, this is all pure speculation. But it’s rather fun to think about food in different ways. And considering the fact that there are thousands of known apple varieties, it’s not unreasonable to speculate about the changes that could have created a banana apple.
Heirloom apple varieties are a thriving business. Christmas Cove Farm, near Northport, Michigan, specializes in cultivating “antique apples.” John and Phyllis Kilcherman have spent over three decades preserving apple varieties that would otherwise be lost. In an interview with Mike Norton of the Traverse City Convention and Visitors Bureau, John Kilcherman said, “We’ve had people stand here and cry. An apple can mean so much to someone. Maybe they were married under a particular apple tree or had one in front of their house. There is a strange connection between people and apples.”
And this connection between people and apples enriches our recipes and our autumns.
Works Cited
On Food and Cooking