It is all too easy to underestimate how much different cooking methods can impact the levels of nutrients your meal contains. Even if you select quality ingredients with the highest nutritional value, much of their goodness can be lost in the cooking process.
Cooking food is often essential to aid digestion and improve nutrient absorption. For example, cooking legumes such as chickpeas improves their digestibility, reduces detrimental ‘anti-nutrients,’ and enhances flavor and texture.
However, all ingredients and foodstuffs will be altered by the cooking process, causing key nutrients to be lost. The biggest impact is on the levels of vitamins and minerals, particularly water-soluble B vitamins and vitamin C, fat-soluble vitamins A, D, E, and K, and potassium, magnesium, sodium, and calcium.
By carefully selecting the ideal cooking methods for meal preparation, we can make the most out of our responsibly sourced sustainable ingredients, helping to retain nutritional value while making the most of their incredible flavor.
Steaming
Steaming is one of the best ways to preserve nutrients, particularly in vegetables with high levels of minerals and water-soluble vitamins. Various studies have revealed the following advantages of steaming over alternative cooking methods when it comes to nutrient retention:
- Cauliflower, carrots, and sweet potatoes all retain higher levels of antioxidants and other nutrients when steamed vs boiled.
- When steamed, broccoli retains higher levels of vitamin C and water-soluble proteins than any other cooking method.
- Steamed fish retains higher protein levels and is less likely to suffer from vitamin and mineral loss.
Many of us steer clear of steaming as a cooking method, as the results have a reputation for being bland and tasteless compared to roasting or grilling. However, adding flavorings such as herbs and garlic to the cooking water and seasoning steamed foods with healthy oils after cooking will bring these nutrient-packed ingredients to life, creating a taste sensation the whole family will enjoy.
Grilling
Grilling and broiling are popular cooking methods that utilize dry heat from above or below to create a delicious caramelized flavor. This is thanks to a process called the Maillard reaction, where sugars and proteins react to heat to generate different flavor profiles and a distinctive brown coloring.
Although the Maillard reaction creates some incredible flavors, it is a mixed bag when it comes to nutrient-rich cooking. This process creates various compounds, some of which have health benefits but others that are thought to increase the risk of cancer. Grilled foods can also lose up to 40% of B vitamins and minerals through moisture evaporation.
To retain nutrients and reduce levels of harmful compounds when grilling, follow these tips:
- Add some veggies to your grill - grilled vegetables retain more nutrients and are lower in potential carcinogens than meat.
- Select thinly sliced lean cuts of meat without any skin and marinade them before grilling.
- Reduce grilling time by cooking meat on an alternative heat source first.
- Minimize direct heat and avoid excessive charring by flipping food frequently.
Roasting
Roasting, where food is cooked in an oven with dry heat, has variable effects on the nutritional value of food:
- Lightly roasted vegetables retain most of their vitamin and mineral content, but these levels quickly deteriorate when exposed to high temperatures for prolonged periods.
- Roasting meat at high temperatures causes protein and lipid oxidation, increasing harmful free radicals.
- Roast chicken is healthier than fried chicken, especially when no additional fats are used.
Avoiding overcooking or excessive charring is the best way to retain nutrients in roast or baked foods. Cut vegetables into larger chunks and keep cooking times to a minimum, especially when using high temperatures. Switch to healthier fats for roasting, such as sunflower or rapeseed oil.
When roasting meat and poultry, stick to recommended cooking times and temperatures, keeping the dish covered to minimize nutrient losses through evaporation. Utilizing juices from roast meats and poultry to make sauces can be a great way to retain nutrients, but fats should be carefully skimmed from the surface first.
Boiling
Boiling is a quick and easy way to prepare foodstuffs, particularly vegetables and potatoes. Unfortunately, although boiling might be simple and fast, it is also a surefire way to destroy many health-boosting nutrients in your recipe!
Water-soluble vitamins and minerals are particularly susceptible to losses through water-based cooking methods. Studies have shown that spinach can lose up to 70% of its vitamin C when boiled, along with leaching of beneficial water-soluble antioxidants into the cooking water. Most boiled vegetables also undergo significant losses of minerals such as potassium, magnesium, zinc, copper, and manganese.
There is some good news regarding this cooking method – boiled fish retains higher levels of omega-3 fatty acids than their fried counterparts, and boiling meat minimally affects overall protein levels.
To preserve nutrients when boiling, use as little water as possible and keep cooking times to a minimum. Cut vegetables into larger chunks and avoid peeling if possible. Reserve nutrient-rich liquid or juices in the pan for making sauces or as a base for a soup or stock.
Sautéing and Stir-frying
You may be surprised to hear that sautéing and stir-frying are key allies in our search for nutrient-rich cooking methods! Cooking food rapidly without the use of water minimizes losses of water-soluble vitamins and can even enhance levels of beneficial compounds in some foodstuffs:
- Fats used in stir-frying can increase the availability of fat-soluble vitamins. Stir-fried carrots contain far higher levels of provitamin A than their raw counterparts.
- Stir-frying has been shown to be the most effective way to preserve antioxidants, vitamin C, and carotenoids in red peppers.
- Sauteing tomatoes in olive oil on a low heat increases the availability of lycopene, a carotenoid thought to reduce the risk of cancer and heart disease.
Stir-frying is also a great way to quickly cook thin strips of meat and poultry, minimizing protein breakdown and nutrient losses.
But before you start stir-frying and sauteing everything in sight, it’s not all good news! Brassicas such as cabbage and broccoli don’t fare well during this cooking process and have better nutrient retention if steamed.
When sautéing or stir-frying, selecting the best oil is the key to optimal nutrient preservation. Oils with a high smoke point can be heated to higher temperatures without the risk of burning, making them ideal for this speedy cooking technique. Good options are canola oil, sunflower oil, rice bran oil, and peanut oil. Grapeseed and avocado are more expensive oil options, but both add beneficial antioxidants and healthy fats to your dish.
Microwaving
Microwaves are easily overlooked as a cooking method, with many of us using them just for defrosting or reheating. But this little gadget is the unsung hero of nutrient-rich cooking, with some remarkable benefits!
Aside from steaming, microwave cooking is one of the best ways to retain nutrients in vegetables, thanks to the low levels of water required. In fact, this method is very similar to steaming, with the added benefit that any residual juices can be incorporated into sauces or stocks.
Cooking meat and poultry in the microwave is also a great way to preserve nutrients, but extreme care must be taken to ensure they are safe to eat. Food will not cook evenly in a microwave oven, so regular stirring or rotation is required. Test cooked food in several places with a food thermometer to be sure it has reached the recommended temperature to destroy bacteria. (Meat and fish: 145F; ground meats and eggs: 160F; poultry: 165F).
Tips to Reduce Nutrient Loss When Cooking
Through some very simple changes in cooking habits, it is easy to drastically reduce nutrient losses when cooking:
- Use high-quality ingredients that have been stored correctly to keep them in peak condition.
- Vegetable peel helps to reduce the leaching of nutrients – don’t peel vegetables until they are cooked, or, even better, don’t peel them at all!
- Use as little water as possible when cooking vegetables, and cook them for the shortest time necessary to achieve the desired result.
- Skip the baking soda when cooking vegetables in water, as this increases losses of vitamin C.
- If you yearn for that delicious caramelized flavor of grilled food, cook meat and poultry in the oven first before transferring it to the grill. Add in some grilled vegetables to boost the nutritional content of your meal.
- Cooking liquids and meat juices contain precious nutrients leached from ingredients and can be utilized to make sauces, stocks, soups, and gravy. Skim any fat off the surface first to remove harmful saturated fats.
- Store cooked vegetables in an airtight container in the refrigerator and eat within a day or two to reap the maximum nutritional benefit.
It is clear to see that by carefully selecting the right cooking methods, we can maximize the nutrients that are locked into the delicious recipes we prepare. Changing our habits in this way needn’t affect the flavor of the dishes we produce but will help to preserve the nutritional benefits of every mouthful.