How to preserve nutrients while cooking

In this brief guide, we are going to answer the question “how to preserve nutrients while cooking” and discuss the different methods of preserving nutrients while cooking.

How to preserve nutrients while cooking

Nutrients can be preserved by using cooking techniques such as steaming, microwaving and baking. Blanching food before storage will also preserve its nutrient content. All these techniques use either minimum heat or minimum amount of water.

What are the nutrients destroyed while cooking

Nutrients that are most affected by cooking include minerals, water-soluble vitamins and fat-soluble vitamins.

  • Minerals: Minerals include sodium, calcium, potassium and magnesium.
  • Water-soluble vitamins: Vitamins B and C are water-soluble. Cooking techniques that use a lot of water such as boiling causes a loss of these vitamins.
  • Fat-soluble vitamins: Vitamins A, D, E and K are fat-soluble. Cooking techniques that use a lot of fat such as deep-frying causes a loss of these vitamins.

How to preserve the nutrients while cooking

  • Steaming: Steaming is generally the best cooking technique to preserve nutrients.

During steaming, food is kept separate from water so that nutrients remain in the food without leaching into the water. Slicing the vegetables before steaming will reduce the cooking time and retain more nutrients. Care must be taken not to slice into very small pieces as this exposes more surface area, causing more nutrients to be lost.

A drawback of steaming is that it doesn’t add much flavour to food and the food may taste bland. This can be remedied by adding extra seasonings such as salt, pepper and spices.

  • Microwaving: Microwaving is a convenient and safe method to cook food while preserving nutrients. Microwaving is also suitable for preserving the nutrients as it uses a minimal amount of water and has a short cooking time and lower temperature. Microwaving also preserves the antioxidants in food such as mushrooms and garlic.
  • Roasting and baking: Both roasting and baking involve the use of dry heat to cook. 

The term roasting usually refers to meat while baking refers to vegetables, bread and baked desserts.

Since these techniques do not use water, the loss of most nutrients is reduced. However, high temperatures and long cooking times may break down some nutrients. The content of vitamin C in meat products will reduce during baking and roasting due to the high temperature.

  • Blanching: Blanching is the process of immersing food in boiling water and then transferring it into an ice water bath. Blanching reduces the enzyme activity in food that cause changes in flavour, colour and texture. Blanching also reduces the loss of nutrients during storage.

What destroys the nutrients 

  • Incorrect storage conditions: Storing both raw and cooked food under the proper recommended storage conditions will minimise the loss of nutrients. Storing raw fruits and vegetables exposed to sunlight or in a warm environment may destroy the nutrients.
  • Incorrect cleaning method: Fruits and vegetables must not be soaked in water. Loss of water-soluble nutrients can be minimized by scrubbing off the loose soil and dirt under cool, running water and using a paper towel to pat dry.
  • High temperature: High temperatures are responsible for destroying most of the nutrients while cooking. Opt for cooking methods that use low heat. 
  • Too much water: Water-soluble nutrients such as Vitamins B and C are unstable and will leach out of food and degrade easily. To minimise the loss of water-soluble nutrients, use cooking methods that need less water such as microwaves. 

Cooking vegetables without peeling will also reduce the quantity of vitamins lost by leaching to water.

If you are using a cooking technique that used a lot of water such as boiling, try to use the left-over water as a stock for a soup. 

  • Incorrect cooking method: Methods such as grilling and broiling are commonly used to cook meat products due to the unique flavour they produce. However, both grilling and broiling reduce the content of minerals and vitamin B in meat by about 40%.

Frying is another technique that significantly reduces the nutrients of the food. For example, deep-frying fish such as tuna reduces the content of omega-3 fatty acids by 70 – 85%.

  • Freezing and defrosting: Freezing fruits, vegetables and meat for long periods and then defrosting them will cause a loss of nutrients. This applies to both raw and cooked food. Especially with cooked vegetables, try to consume them within 2 days after cooking to get the maximum nutrient content.
  • Using baking soda: Certain recipes recommend the use of baking soda when cooking vegetables as it retains the colour of the vegetables. However, baking soda also creates an alkaline environment that causes the loss of vitamin C.


In this brief guide, we answered the question “how to preserve nutrients while cooking” and discussed the different methods used to preserve nutrients while cooking.

If you have any questions or comments, please let us know.


Hi, I am Charlotte, I love cooking and in my previous life, I was a chef. I bring some of my experience to the recipes on this hub and answer your food questions.