Save big on your family healthcare expenses. Become a myUpchar plus member only at Rs. 99 -

One of the things that makes us very different from other species is the way we consume our food. As homo sapiens evolved, so did our methods of cooking.

We started as hunters and gatherers, which exposed us to a plethora of ingredients. There is some evidence that our ancestors could control fire about one million years ago and started cooking 500,000 years ago: the legend goes that an early human accidentally dropped a piece of meat in an open fire. The fire tenderised the meat, made it taste better and more digestible.

Then came agriculture and granaries, and we started eating (and living) differently. The affair with cooking continued and grew, though. Archaeologists have found 20,000-year-old clay pots with soot marks that show they were used for cooking in China all those years ago. Slowly but surely, cooking gained in popularity.

Over time, we learnt to cure, roast, smoke, barbecue, boil, blanch, steam, fry, marinate, stew, grill, bake, microwave, dehydrate, juice, stir-fry, pickle, ferment—not necessarily in that order.

Of course, cooking food is not just about making it tender. Done right, cooking gets rid of the germs, brings out the best flavour in food, and increases its digestibility—our body can absorb more nutrients from cooked food than raw food. 

Lately, though, there's been a debate around whether cooking makes food better or worse for health. True, cooking can reduce some of the nutritive value of food—for example, water-soluble vitamins like vitamin B and vitamin C can be washed out by boiling and straining the food. But some types of "cooking" or food processing can enhance its nutritive value; for example, fermented foods like idlis, dhokla and gajar kanji drink improve gut health.

The cooking method we choose doesn't just change the texture, taste and temperature of the food, but also what it has to offer in terms of nutrients. Read on to know about the effects of different methods of cooking on the nutritive value of food and the best cooking method to preserve nutrition.

  1. Is it healthy to microwave food?
  2. Is roasting and baking healthy?
  3. Healthy food: frying and stir-frying
  4. Steam cook food for better health
  5. Boil, simmer, poach food to preserve nutrients
  6. Fermenting food improves nutritional value
  7. Tips to maximize nutrient retention during cooking
  8. Takeaways
  9. Doctors for Best cooking method to retain nutrients

We are all aware that microwaving is an extremely easy and convenient way of preparing your food. What makes it even better is the fact that microwave-cooked food is the healthiest alternative in terms of nutritional value.

Short cooking times and reduced exposure to heat preserve the nutrients in microwaved food. Only 20–30% of the vitamin C in green vegetables is lost during microwaving, which is less than most cooking methods.

In fact, studies have found that microwaving is the best method for retaining the antioxidant activity of garlic and mushrooms.

Baking refers to cooking food in an oven with dry heat. Roasting can be done in an oven or on an open flame.

Even though baking and roasting are used interchangeably, they are somewhat different. Roasting is typically used for meat while baking is used for bread, muffins, cake, and similar foods.

Vitamin losses are minimal with this cooking method, including vitamin C. However, due to long cooking times at high temperatures, the vitamin B in roasted meat may decline by as much as 40%.

Longer duration of cooking at high temperatures in an oven is also associated with loss of fat-soluble vitamins like vitamin A.

Frying

While frying is the most beloved cooking technique there is, not all foods are appropriate for frying. Fatty fish are the best sources of omega-3 fatty acids, which have many health benefits. However, these fats are very delicate and prone to damage at high temperatures. For example, frying tuna has been shown to degrade its omega-3 content by up to 70-85%, while baking causes only minimal losses.

In contrast, frying preserves vitamin C and B, and it may also increase the amount of fibre in potatoes by converting the starch in them into resistant starch.

Stir-frying

Stir-frying comprises cooking food for a very short time over very high heat in a large wok—the food is stirred often, and cooked in oil or butter. (Read more: How to choose the right oil for cooking?)

This is a healthy way to prepare food. Cooking for a short time without water prevents the loss of B vitamins, and the addition of fat improves the absorption of plant compounds and antioxidants.

A study found that our body can absorb 6.5 times more beta carotene from stir-fried carrots than raw ones.

However, stir-frying has been shown to significantly reduce the amount of vitamin C in broccoli and red cabbage.

Steaming is one of the best cooking methods for preserving nutrients, including water-soluble vitamins, which are sensitive to heat and water. Researchers have found that steaming broccoli, spinach, and lettuce reduces their vitamin C content by only 9-15%. The downside is that steamed vegetables may taste bland. However, this is easy to remedy by adding some seasoning and oil or butter after cooking.

Boiling, simmering and poaching are all water-based cooking methods. These techniques differ in terms of the temperature of the water:

  • Poaching: less than 180°F (82°C)
  • Simmering: 185-200°F (85-93°C)
  • Boiling: 212°F (100°C)

Vegetables are generally a great source of vitamin C, but a large amount of it is lost when the vegetables are cooked in water. B vitamins are similarly heat-sensitive. Up to 60% of thiamine (vitamin B1), niacin, and other B vitamins may be lost when meat is simmered and its juices run off.

However, when the liquid containing these juices is consumed, 100% of the minerals and 70-90% of B vitamins are retained, which is why it is a wonderful idea to save up the vegetable and meat stock.

A sous-vide machine—though it uses water—does not let the food come in contact with the water or oxygen. That is why the food tends to preserve many of the nutrients. A study published in Food Science & Nutrition, a peer-reviewed journal, in May 2017 found that cereals and lentils prepared in a sous-vide machine had higher mineral content than the same foods cooked traditionally. However, the machine is expensive and the cooking method can be slow.

Fermentation is an old technique for processing foods that is seen in many cultures around the world. Think about fizzy and sour foods and drinks you might have consumed in the past; many of these are fermented. Some common examples include:

  • Dhokla
  • Idli
  • Dosa
  • Gajar kanji
  • Kimchi
  • Sauerkraut
  • Gundruk
  • Wine, including Mahua wine
  • Beer

Fermented foods are basically those foods (or drinks) that have been prepared by adding yeast or another microbial culture. The food is then set aside, to allow the microbes to break down the sugars and other compounds to make the food slightly tart and very nutritious (you'll see bubbles rising as the food ferments). Research has found that fermented foods can be rich in vitamin B12, as well as improving gut microbiome and digestion.

Here are a few things to keep in mind while cooking, to reduce nutrient loss:

  • Use as little water as possible when poaching or boiling.
  • If you are cooking non-veg, collect any juices dripping from meat and add them back into the pan.
  • Don't peel vegetables until after cooking them. Better yet, don't peel at all to maximize their fibre and nutrient density. For example, most of the vitamin C in potato is in the skin. So try not to peel potatoes before you cook them.
  • Try to eat any cooked vegetables within a day or two, as their vitamin C content may continue to decline when the cooked food is exposed to air.
  • Cut food after—rather than before—cooking, if possible. When food is cooked whole, less of it is exposed to heat and water.
  • Cook vegetables for only a few minutes whenever possible.

While cooking, it is important to abide by certain rules: to remember that the duration, temperature and technique of cooking are all important to get the most out of the food we eat (bioavailability of nutrients as well as the taste and texture of food).

Some cooking methods are generally healthier than others. For example, compared with deep-frying or shallow frying (used for paratha and patties, for example), stir-frying uses less oil and can preserve more nutrients in food. And compared with boiling, blanching vegetables can preserve more nutrients (and texture) as the duration of cooking is much less.

Some methods like fermentation enhance the nutritive value of food. Other methods like curing (for example, curing fish or meat in lots of salt) can improve their shelf life (and often taste) tremendously. Cooking improves the digestibility of food and kills microbes—some of which can cause food poisoning.

Certain recipes are also created with their nutritive value in mind. For example, adding amchur to food increases the body's ability to absorb zinc from it.

Cooking helps us break down foods more easily than eating them raw. The spices and condiments we add also help the body absorb the nutrients. That said, overcooking food, reheating it multiple times or storing it in the fridge for many days can erode its healthfulness—foods that are cooked or stored improperly can indeed do more harm than good.

 

Dt. Akanksha Mishra

Dt. Akanksha Mishra

Nutritionist
7 Years of Experience

Surbhi Singh

Surbhi Singh

Nutritionist
22 Years of Experience

Dr. Avtar Singh Kochar

Dr. Avtar Singh Kochar

Nutritionist
20 Years of Experience

Dr. priyamwada

Dr. priyamwada

Nutritionist
7 Years of Experience

और पढ़ें ...

References

  1. Harvard Health Publishing, Harvard Medical School [Internet]. Fermented foods can add depth to your diet.
  2. Wang Yong, Li Amin and Chen Dongpo. Status and prospects of nutritional cooking. Food Quality and Safety, August 2019; 3(3): 137–143.
  3. Rondanelli M., Daglia M., Meneghini S., Di Lorenzo A., Peroni G., Faliva M.A. and Perna S. Nutritional advantages of sous-vide cooking compared to boiling on cereals and legumes: Determination of ashes and metals content in ready-to-eat products. Food Science & Nutrition, May 2017; 5(3): 827-833. PMID: 28572974.
  4. Das D. and Goyal A. Potential probiotic attributes and antagonistic activity of an indigenous isolate Lactobacillus plantarum DM5 from an ethnic fermented beverage “Marcha” of North Eastern Himalayas. International Journal of Food Sciences and Nutrition, 2014; 65(3): 335-344.
  5. Zotos A., Kotaras A. and Mikras E. Effect of baking of sardine (Sardina pilchardus) and frying of anchovy (Engraulis encrasicholus) in olive and sunflower oil on their quality. Food Science & Technology International, 2013; 19(1): 11-23.
  6. Hoffman C.J. and Zabik M.E. Effects of microwave cooking/reheating on nutrients and food systems: a review of recent studies. Journal of the American Dietetic Association, 1985; 85(8): 922-926.
  7. Stephen N.M., Shakila R.J., Jeyasekaran G. and Sukumar D. [linl]. Journal of Food Science and Technology, April 2010; 47 (2): 174–181.
  8. Xu F., Zheng Y., Yang Z., Cao S., Shao X., Wang H. Domestic cooking methods affect the nutritional quality of red cabbage. Food Chemistry, 15 October 2014; 161: 162-167.
  9. Yuan G.F., Sun B., Yuan J. and Wang Q.M. Effects of different cooking methods on health-promoting compounds of broccoli. Journal of Zhejiang University Science B, August 2009; 10(8): 580-588. PMID: 19650196
  10. Sreeramulu N., Ndossi G.D. and Mtotomwema K. Effect of cooking on the nutritive value of common food plants of Tanzania: Part 1—Vitamin C in some of the wild green leafy vegetables. Food Chemistry, 1983; 10(3): 205-210.
ऐप पर पढ़ें