Scientists in Germany have discovered a new ‘super’ apple juice which has the potential to improve heart health by boosting blood flow.
Researchers at Hochschule Geisenheim University, near Frankfurt, have found a way to maximise polyphenols in apple juice by using a novel squeezing method called a spiral filter press.
This process actively takes out oxygen by utilising a vacuum-driven method. Moreover, it was ensured that oxygen was excluded from all other processing steps, therefore reducing nutrient deterioration.
The new study, published in Food Research International, found that this new method boosted polyphenol content by four times compared to regular apple juice.
Polyphenols are natural plant compounds found in fruit, red wine, and cocoa which are known to have a range of health benefits for the heart and brain.
A 280 ml serving of the new apple juice would be enough to provide 100% of the ideal intake for a key group of polyphenols, called flavan-3-ols, which help promote a healthy blood flow.
The ideal intake of 400–600 milligrams per day for cardiovascular health was proposed by an international consortium of scientists in 2022.
The British Heart Foundation estimates that there are 7.6m people living in the UK with heart or circulatory diseases.
Meanwhile, data from the 2021 census show that 32% of adults suffered from high blood pressure (hypertension) and 3 in 10 of those (29%) were undiagnosed; equating to approximately 4.2 million adults with undiagnosed hypertension.
Lead author of the paper, Professor Ralf Schweiggert, commented: “Apple juice is already a source of polyphenol compounds, but you would need to drink several glasses to reach the levels recommended by scientists for heart health effects. The new juicing method that we’ve investigated takes the polyphenol content to a new level by minimising the nutrient losses we typically see during juicing.”
Co-Researcher of the study, Stefan Dussling, said: “Nutrient losses are commonly due to the presence of oxygen, which quickly degrades some of the nutrients in apple juice like flavan-3-ols or vitamin C. This would happen when we juice apples at home or buy a ready-made product. We hope that the new juicing method will be used more widely in the future to help people get more of these beneficial natural compounds simply by drinking one glass of juice”.