Boiled, fried or juiced, what is the best way to prepare spinach and have we been getting it all wrong?
Researchers from Linköping University in Sweden investigated the best way to obtain the antioxidant lutein from spinach.
What are the benefits of lutein?
The antioxidant lutein is a natural fat-soluble pigment found in plants, particularly in dark green vegetables.
Previous research from Linköping University found that lutein can reduce inflammation in immune cells in people with coronary artery disease. They also found that it can be stored in immune cells, which means that it is possible to build up a reserve of lutein in the body.
To test the best way to increase lutein dietary intake, researchers tried different preparation methods on baby spinach and measured the lutein content.
Boiled, fried and reheated
Like many other nutrients, lutein is degraded by heat.
The study found that heating time is also important when spinach is boiled – the longer it is boiled, the less lutein retains. And when spinach is fried at high temperature, a large fraction of the lutein is degraded after only two minutes.
Interestingly, the researchers found that lutein is released as the plant structure is broken down further by the microwave. This means that, to some extent, reheating spinach in a microwave compensates for the loss of lutein in cooked food.
Did someone say smoothie?
The research concluded that the best way to obtain the antioxidant lutein from spinach is not to cook it at all.
“Best is not to heat the spinach at all. And even better is to make a smoothie and add fat from dairy products, such as cream, milk or yoghurt. When the spinach is chopped into small pieces, more lutein is released from the leaves, and the fat increases the solubility of the lutein in the fluid,” says postdoc Rosanna Chung, principal author of the article.
Source: Linköping University via www.sciencedaily.com