Modern apples are bigger and less acidic than their ancestors

Apples are among the most popular fruits in the world, dating back at least 7,000 years. A new study led by the Dalhousie University in Canada has found that modern apples are bigger, less acidic and bitter, and stay fresh for longer than their wild ancestors. According to the scientists, these changes have been caused by processes of domestication and breeding.

The scientists analyzed data from Canada’s Apple Biodiversity Collection, which contains information on over 1,000 different apple varieties, including modern ones such as Gala or Honeycrisp, as well as wild apples from the forests of Kazakhstan and ancient heirloom varieties. 

In order to compare modern apples with their ancient counterparts, the researchers examined ten traits: weight, firmness, acidity, precocity, flowering date, harvest date, soluble solids, phenolic content, percentage change in firmness during storage, and percentage change in acidity during storage. 

They discovered that modern apples were 3.6 times heavier than their ancestors. “Consumers prefer large, visually appealing fruit so selection for large fruit size may explain our observation,” explained the study authors.

Moreover, the apples that we consume today were found to be half as acidic and less bitter than the ancient varieties. “Acidity contributes to the sour taste of apples, and apple preference is heavily influenced by acid/sugar ratios. Given this relationship, it is not surprising that cultivated apples, which are primarily consumed as fresh fruit, have lower acid than wild apples,” wrote the scientists.

A thorough investigation of the historical record has also revealed that advancements in apple breeding over the past two centuries has resulted in varieties which soften less during storage. The need for extended periods of storage and long-distance shipping of apples made cultivators search for solutions to reduce softening during storage and improve firmness retention. 

These findings provide strong evidence of how much modern apples changed over the course of their 7,000-year-old history.

“Our results quantify the significant changes in phenotype that have taken place since apple domestication, and provide evidence that apple breeding has led to continued phenotypic divergence of the cultivated apple from its wild progenitor species,” the scientists concluded.

The study is published in the journal PLoS ONE.  

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By Andrei Ionescu, Earth.com Staff Writer