Researchers from Italy report that cooking vegetables can preserve and even increase their nutritional value compared to fresh vegetables
Many people claim that fresh vegetables are more nutritious than cooked vegetables, but more and more research suggests that cooking may actually increase the release of some nutrients. Nicoletta Pellegrini and her research colleagues tried to reach a deeper understanding of the nutritional properties of cooked vegetables.
The researchers evaluated the effects of three common cooking methods in Italy - steaming, frying and cooking in boiling water - on the nutritional value of carrots, zucchini and broccoli. Cooking and steaming did not harm the antioxidant compounds of the vegetables, but frying caused a significant loss of antioxidants compared to cooking and steaming. In the case of the broccoli, steaming actually increased the amount of free glucose-inolate, which is a group of plant substances known for their anti-cancer properties.
In an article to be published in the American Chemical Society's 'Food and Agriculture Chemistry' magazine, the researchers suggest that in the future we will be able to choose a unique cooking method for each type of vegetable, which will be able to preserve and improve its nutritional value - and hopefully also its taste.
13 תגובות
I have been cooking for many years in GCC pots where you cook without water and fry without oil (they have no coating)
The advantage of cooking vegetables is that they also cook without water in a short time and without reaching a boiling temperature, but only between 60 and 70 degrees.
Cooking without water prevents the solubility of vitamins and minerals in water - because there is no water - and they are kept inside the cooked vegetable and we get a maximum amount of them. The cooking is shortened because there is no water that accumulates heat, but the heat goes directly to the vegetable and thus the cooking is short and the pot on the lid has a thermometer that tells you when to reduce the strength of the stove and when to turn it off
recommended!
to shade
Isn't this steaming with boiling water under the dish without touching the dish?
So no... I was talking about very hot air about 300 degrees that fries everything called in its way similar to a cooking oven except that it is hot air and not a grill or a heating element! Maybe it will turn out that there is not much difference between them, but for that you have to try!
Personally, I was very sorry that I didn't purchase the heat gun then! I wanted to check many things with him.
You mean "vaporization" which is a very common way
Mainly meat
I didn't mention that I didn't finally buy the heat gun (due to lack of money)! And so I couldn't try to fry chips with a gun either! Heat !
to shade
Indeed, you understood correctly, cooking preserves anti-oxidizing properties that are important for the elimination of free radicals in the body! Cooking releases good substances as Cezana pointed out in his response to you and also new molecules are formed instead of others that are destroyed and the new ones (according to Cezana) are better than the ones that were destroyed!
Regarding increasing/decreasing calories, this may also happen, but it is not detailed here!
I would like to add regarding the bad frying, maybe it is possible to fry without oil and thus sterilize the bad effects of frying! What does the oil do? Transfers heat to the fried food, let's say chips..Also, the oil, as we know, increases the heat to about 300 degrees compared to the 100 degrees that the water can reach (in a pressure cooker, the heat is higher) and also the problem that the water is absorbed by the food..therefore the idea (my old one) is a substitute for oil In another way, in which heat will be created that will fry the chips without oil, and what happened then was very simple...hot air! Because at that time I tried to find a way to heat plastic pipes (1993) to bend them and the gas burner method would burn them if you are not careful! In short, I found another method and that is heating with "hot oil" and it worked great, only the way of working changed! So I looked for other sources of heat that do not "burn" and found at one of the annual technology exhibitions in the exhibition grounds, "heat guns" that are exactly similar to a hair dryer, only that they reach 300 degrees!!
Then one day when I was thinking about frying chips I connected the two things and that's how the idea of frying without oil was born which I have never tried!
Such facilities may already exist (as it turned out with scientific cookbooks) and if not... it's worth a try! Probably the results will be different from literally frying with oil!
I mean, if I understood correctly
and since the basic composition does not change,
You can say that new molecules are formed
Have a higher nutritional value??
A more interesting question
Is it possible as a result of net heating (without frying-adding oil)
Can the substance increase/decrease the amount of calories?
This can be an amazing platform!
Thank you Omar.. It does seem that the book is interesting and there are about ten other books on the same topic that connect science and food. The problem is that the books are in English with which I have a problem understanding..because I'm not fluent but I just wanted to see where we found what, it doesn't bother me and when they're translated into Hebrew and sold here I'll go buy it!
Second, Amazon is a stupid site, even very stupid. How do they expect people to buy a book without a summary? Did we buy a cat in a sack? Also, the publication date of the book is missing, which can be critical for certain books, and I just wanted to know when these books were written!
By the way, I am trying to write about a book that I buy the date of purchase, price, and place of purchase... because over time it became clear that these are important things that bothered me when I wanted for various reasons to know when and where and how much! Now I understand that I lack a "why" because I bought most of the books for specific reasons and there is almost no reason that has repeated itself!
D. Peretz - such books have already been written. for example: The science of cooking
Regarding tomatoes, this effect has been known for a long time,
Cooking releases lycopene - one of the antioxidants
The most powerful oxidant known today.
I have always claimed that cooking is the most successful branch of chemistry!
Tsila, not everything my mother says is also scientifically true!! Although of course mother knows everything best!
At this rate, scientists will write cookbooks.. not a bad idea by the way, or for cookbooks to have a scientific section added to each dish that includes nutritional values and healthy cooking time or steaming and what happens in frying and more!
Tsila,
Your mother is generally right. Cooking can indeed release vitamins, but this is not always a bad thing. In onions, for example, the biotin is too strongly attached to the other molecules and it is necessary to cook for 30 minutes to allow the biotin to be released.
Regarding the destruction of the molecular bonds, this is also not necessarily a harmful phenomenon. As an example, cooking garlic results in two types of molecules breaking down, and we get five different smaller molecular groups, some of which exhibit anti-cancer properties.
Regarding the time, of course each vegetable should be cooked or steamed only for a certain period of time and if we cook for a longer time we will find that its nutritional value does decrease.
thank you for your response,
Roy.
My mother claims that cooking releases the vitamins and destroys the bonds of the molecular structures
There is also no reference to time-which serves as a catalyst
in the destruction and decomposition of the organic matter