Jonagold, Boskop or Elstar: apples are the Germans' favorite fruit. There are almost 2,000 different varieties in the country. The fruit has few calories, but many healthy ingredients such as vitamins and minerals. Researchers at Osnabrück University of Applied Sciences have developed an apple that is even richer in one health-promoting ingredient and is also said to strengthen the immune system. The innovation: The new fruit called Selstar impresses with a particularly high selenium content. Compared to other apples, the fruit contains more than ten times as much selenium, covering around one third of a person's daily requirement.

Algae fertilizer promotes selenium uptake in apples

Selenium is a vital trace element. It is found in many foods, but only in small amounts. A deficiency of selenium can weaken the immune system and lead to diseases of the intestines, liver and thyroid. Recent studies show that it can even increase the risk of death in COVID-19 patients. Vegetarians and vegans in particular, as well as pregnant and breastfeeding women, are often undersupplied. The amount of selenium in apples is 10% because plants normally grow in selenium-deficient soil. "The high proportion of selenium in Selstar results from a special cultivation process that enables the apple trees to better absorb selenium and store it in the fruit," explains Diemo Daum from Osnabrück University of Applied Sciences. A special algae fertilizer is used for this purpose.