Apples are the most popular fruit in this country: on average, each German eats almost 25 kilograms a year. Today’s fruits have little in common with their wild Asian predecessors: larger, less acidic, firmer.
They’re also probably less healthy, according to a study published in the journal Plos One.
The researchers hope that their analyzes can help in the development of new varieties in which the health-promoting properties of wild relatives can be reused.
Fruit on the Silk Road
Today’s cultivated apples are probably descended from the Asian crabapple (Malus sieversiilisten)) that originated in present-day Kazakhstan. In 2017, scientists used genomic analyzes in the journal Nature Communications to show how it spread west and east along the Silk Road.
However, these wild varieties probably developed comparatively large fleshy fruits millions of years before they were cultivated to represent an attractive food source for large mammals such as deer. At least those are the conclusions of another study by researchers at the Max Planck Institute for the Science of Human History in Jena.
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But what do today’s cultivated apples (Malus domestica) still have to do with their wild ancestors? Very little, according to the results of the current study conducted at Canadian Dalhousie University. A team led by geneticist Sean Myles examined ten characteristics of fruits from the Canadian “Apple Biodiversity Collection,” which includes more than 1,000 different varieties of apples, including 78 variants of the crabapple.
Late flowering but no wilting.
As their analysis showed, wild and cultivated apples differ phenotypically in some cases significantly: cultivated apple trees flower and bear fruit at an earlier age than their wild relatives, which is an important factor for farmers. In addition, the cultivated apples flowered an average of three days later. “Frost during bloom can result in fruit loss, damage, or reduced marketability, making timing of bloom an important consideration for fruit growers when establishing orchards,” the authors write.
Also, apples with a later bloom date tend to be firmer, which not only makes them easier to store and transport over long distances, but is also favored by consumers.
Another consumer preference would also explain the taste and size differences between wild and domesticated apples: The latter are on average 3.6 times heavier and have 43 percent less acidity, the researchers report. The differences are even clearer when it comes to polyphenol content. These aromatic compounds are among the phytochemicals whose antioxidant and health-promoting effects are at least partially proven.
According to scientists, the content of these is on average 68 percent lower in cultivated apples than in wild apples. This finding is also likely due to consumer preferences, because high phenol content means apples taste less sweet and also brown more quickly.
So do the findings ultimately mean that today’s apples are less healthy than their wild ancestors? Yes, says lead author Sean Myles. When asked, he cites a study published in the journal Biotechnology Reports: “Plant phenols are considered a vital part of the human diet and have tremendous antioxidant effects as well as other health benefits.”
The dose makes the apple healthy
Epidemiological evidence suggests that a diet rich in antioxidant fruits and vegetables reduces the risk of many diseases, including cancer, diabetes, and cardiovascular disease. Myles: “So it’s safe to say that the health benefits we get from apple polyphenols today are probably less than the health benefits people got from apple polyphenols in the past.”
As a result, cultivated apples are probably more digestible in larger quantities. Because phytochemicals that promote health in small doses can also be irritating and even have a poisonous effect in higher doses, a phenomenon known as “hormesis.” Here, too, there may be an economic side effect of breeding: the more apples a person can tolerate, the more they can sell overall.
Cross wild varieties, improve cultivated varieties, serve Äppelwoi
Many nutritional researchers also find the higher fructose content compared to wild varieties problematic, which is considered a long-lasting metabolic toxin in high doses.
In general, the study concludes, the domestication of the apple would have led to increasing deviations in numerous traits compared to wild ancestors. Both are now largely separate groups. However, an approach by crossing old varieties, as is already being attempted elsewhere, would be worthwhile, as the authors write: “Breeders could use the high phenol content of crabapples to improve the nutrient quality of apples.” cultivated”. the cider industry, which values high acidity and phenolic content. (with teaspoon)