Scientist say mushrooms are better grilled or microwaved

Mushrooms are better grilled or microwaved, scientists say, as the two cooking methods guarantee that you will enjoy to the fullest their nutritional value.

Mushrooms have reached an almost revered status when it comes to healthy eating especially as they are a good source of protein, are rich in antioxidants like polyphenol and also provide vitamins and trace amounts of minerals.

And for those looking to get the best out of their mushrooms, scientists have looked at different types and different cooking methods to see how the nutritional value changes in relation to heat. Of particular interest was the way in which antioxidants are preserved or destroyed during the cooking process.

Scientists at the Mushroom Technological Research Center at La Rioja, Spain, tested four types of raw and cooked fungi and measured their antioxidant activity. Researchers took the four most common types of mushrooms, white button mushroom, shiitake, oyster mushrooms and king oyster mushrooms and started boiling, microwaving, grilling and frying.

After this, the mushrooms’ nutritional value was calculated. Researchers found that frying induced more severe losses in protein, ash, and carbohydrates content but increased the fat and energy. Boiling improved the total glucans content by enhancing the beta glucans fraction. A significant decrease was detected in the antioxidant activity, especially after boiling and frying, while grilled and microwaved mushrooms reached higher values of antioxidant activity.

“Frying and boiling treatments produced more severe losses in proteins and antioxidants compounds, probably due to the leaching of soluble substances in the water or in the oil, which may significantly influence the nutritional value of the final product” says Irene Roncero, one of the authors of the paper, according to Eureka Alerts.

In the article the scientists published in the International Journal of Food Sciences and Nutrition, the recommendation was simple, to get the best nutritional value, mushrooms have to be grilled of microwaved.

“When mushrooms were cooked by microwave or grill, the content of polyphenol and antioxidant activity increased significantly, and there are no significant losses in nutritional value of the cooked mushrooms” says Roncero.

And for those that like a little oil to go with their mushrooms, scientists also have a good news. A little bit of oil can actually do a lot of good as it enhances the active substances and does not lead to them leaching out.

“This minimal amount will not cause nutrient loses by leaching; in fact, the antioxidant capacity can be even improved. Moreover, if olive oil is used, the fatty acid profile of the final preparation is enhanced with barely increase in the calorie content,” Roncero added.

This is not the first time that scientists have turned their labs into improvised kitchens in order to find out how to best cook the vegetables, in order to fully enjoy their nutritional value. A 2009 study, also looking into traditional forms of cooking, tested 20 of the most commonly used vegetables.

They found that the artichoke was the only vegetable that kept its very high antioxidant activity after all four methods. The highest losses of antioxidant capacity were observed in cauliflower after boiling and microwaving, pea after boiling, and zucchini after boiling and frying.

Beetroot, green bean, and garlic kept their antioxidant activity after most cooking treatments. Swiss chard and pepper lost scavenging capacity in all the processes. Celery increased its antioxidant capacity in all the cooking methods, except boiling.