Vegetables and legumes have been widely known to have great benefits to our health and well being. They are rich in protein, fats, carbohydrates, as well as vitamins and minerals such as, vitamin A, C, E, K, and multiple B-vitamins. Many of their benefits include antioxidant activities, prevention of many adverse health diseases, including nutrient deficiencies as well as vitamin and mineral deficiencies. However, the process of preparing and cooking can affect the nutrients available in these food items. Some processes can increase the amount of nutrients, while other processes can decrease the nutrients available in vegetables and legumes.
Common cooking methods include steaming, roasting, boiling, frying, sautéing, sous-vide, microwaving, and pressure-cooking. Many studies have found steaming to be the best method for retaining nutrients, such as folate in collard greens and broccoli and improving the antioxidant capabilities of vegetables by retaining vitamin C. It was also found to reduce the risk of heart disease by enhancing the cholesterol lowering qualities in vegetables, while also have the added benefit of improving flavor and texture.
Sautéing was the best method to use on mustard greens, kale, cabbage, and green bell peppers. For potatoes, sous-vide was shown to enhance folate retention the most. Cooking methods that use large amounts of water, like boiling and blanching, were shown to decrease nutrient content of vegetables, especially vitamin C. The nutrients and vitamins tend to leach out when the vegetables are submerged in large amounts of water, losing many of their benefits. Using methods where the vegetables don’t have direct contact with water like steaming and sous-vide, help with retaining nutrients and maintaining the benefits of the vegetables the best.
Some preparing processes can also influence the availability of nutrients is washing, peeling, cutting, chopping, and soaking. Preparing vegetables by cutting and chopping can damage the cell structure and release nutrients that were previously trapped within the walls. Some preparation methods were also seen to eliminate anti-nutrients found in some vegetables that may be poisonous and harmful to the human body. Those methods include soaking in a salt solution before cooking, especially in beans and pea
s. Soaking was also found to improve protein quality and reduce cooking time and gastric problems usually seen with beans.
In conclusion, when cooking vegetables, the best way to retain nutrients is to use methods that do not have direct contact with water, like sautéing and sous-vide. Preparing vegetables by cutting them beforehand and preparing legumes by soaking in a saltwater solution, helps with increasing benefits and eliminating toxins.
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