"What is unique about this study is that we have used preparation methods that are often used when cooking food at home, and we have compared several temperatures and heating times," coauthor Lena Jonasson said in a statement.
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After analyzing the results, they found blending spinach in a smoothie or juice is this best way to obtain lutein. It’s even more beneficial when a dairy product, such as milk or yogurt, is added.
“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”, coauthor Rosanna Chung explained.
They discovered that heating spinach, by boiling it or steaming it, strips away much of the lutein. In fact, when it is fried at high temperature, a large fraction of the lutein is degraded after only two minutes.
“Best is not to heat the spinach at all,” Chung advised.
Want to learn more about the findings? Take a look at the full assessment here.
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