When you eat apples or bananas, or when peeling potatoes or eggplant, the color of the fruit and vegetables becomes brown and sometimes "changes to black color. All opinions and answers are welcome.
the actual mechanism that causes browning in apples and potatoes involves an enzyme called polyphenol oxidase, also known as tyrosinase. ... The easiest way to prevent browning is to put the sliced apples in water so that the enzyme does not have access to oxygen.
Thank you "DearEman Ali Al-Khafaji, scientific answer and an effective contribution to my appreciation and respect
Dear Nour Shakir ,Fred Romano,Israa Burhanuddin - Abdurrahman, Joshua O. lghalo Thank you "very much" for an interesting and objective discussion, with appreciation and respect for all
Oxidation turns them brown the moment they are peeled and exposed to the air. This is true of many vegetables including potatoes, artichokes, avocados, etc. The moment they are peeled placed them in acidulated water (i.e., water with some lemon squeezed in it) so that the oxidation can be slowed down considerably.
Thank you "very much" Dear Srini Vasan, Dear Adheem Naeem for the valuable answers with appreciation
The explanation is simply that fruits and vegetables contain complex organic compounds called enzymes. These enzymes remain trapped inside plant tissues as long as they are intact, but when any scratch occurs, as is usually the case when peeling fruits and vegetables, the enzymes are exposed to air (oxygen). It activates directly and works on some compounds in fruits and vegetables (phenols) a few minutes and begins to lose their hardness. These enzymes are called oxidase oxidase, which acts on oxidation of phenolic compounds mentioned above to brown or black, known as enzyme interaction
When apples are cut, infected tissues are exposed to oxygen. The inner tissues of the apple contain an enzyme known as polyphenols. These enzymes also stimulate the phenol, which is also found in the apples on oxidation. This stimulation occurs only if the polyphenols can reach the oxygen in the air and the phenols found in the apples, When phenol oxidation begins, this releases many chemical reactions to end up producing a type of protein known as melanin.
When potatoes, eggplant or apples are peeled or cut, certain enzymes are exposed to air. When an enzyme called polyphenol oxidase, also known as tyrosinase is exposed to oxygen, oxidation takes place, which leads to browning of the surfaces of these fruits.
Thank you "for" all of you ", a substantive, interesting and worthy discussion with appreciation and respect
Oxygen is a "killer", very reactive gas and in the end it kills us too (slowly). When it appeared in the air for the first time on this planet it killed all pre-existing life (known as the "gas attack", in the history books). Some survivors escaped in the sea and continued living there till now.
You have interesting questions!
I am a mathematician but from my university knowledge that the reason is due to the presence of the iron element, which is oxidized when touching the air which gives the brown color almost
All cells contain thousands of enzymes that do all of the work necessary for the cell to live its life. The actual mechanism that causes browning in apples and potatoes involves an enzyme called polyphenol oxidase, also known as tyrosinase. The browning reaction results from the oxidation of phenolic compounds in the fruit under the action of an enzyme called polyphenol oxidase (PPO), which is common in plant tissues. Once the fruit was cut or sliced the cell would be open up and the enzyme then has access to oxygen in the air, turning the fruit brown.
The easiest way to prevent browning is to put the sliced apples or potatoes in water so that the enzyme does not have access to oxygen. Another method is that the apples or potato can be heated to denature the enzyme.
if you put orange juice, without water and the peeled fruits in the same recipient, this effect can also be avoided.
Vilemar Magalhães
The browning reaction results from the oxidation of phenolic compounds in the fruit/veg under the action of an enzyme called polyphenol oxidase (PPO), which is common in plant tissues.
They turned black because come in contact with oxygen and oxidation of phenolic compounds takes place.
Oxygen Exposure Hastens Decomposition
If you've noticed how quickly the flesh of an apple turns brown after being exposed to air, you've seen oxidation in action. Some chemicals naturally present in food, called oxidizing enzymes, react to oxygen and speed up the spoilage process upon contact with air. In addition to their need for water, molds, most yeast and many bacteria require oxygen to thrive. The more they get, the faster these microbes work. At best, oxidation undermines the eye appeal of affected fruits and veggies; at worst, it is often accompanied by unpleasant tastes and odors. As well as killing spoilage microbes, blanching also inactivates these enzymes, preventing or arresting oxidation.
Great information and wonderful discussion by colleagues and academic researchers, thank you "very much" to all of you "with appreciation
I agree with my RG colleague respected Dr. Nour answers.
Regards,
Naseer Almukhtar
It’s because of reaction with oxygen and amino acids that will produce melanin, which turns the apple brown.
Process of change in colour is fast in apple and very slow almost nil in case of banana ,it is all about magic of oxygen
the browning reaction results from the oxidation of phenolic compounds in the fruit under the action of an enzyme called polyphenol oxidase (PPO), which is common in plant tissues.
Once you cut the fruit, you open up some of the cells. The enzyme then has access to oxygen in the air and it does its thing, turning the fruit brown. This is the same thing that causes brown spots in apples
When you eat apples or bananas, or when peeling potatoes or eggplant, the color of the fruit and vegetables becomes brown and sometimes "changes to black color, the reason is due to oxidation of phenolic compounds in the fruit under the action of an enzyme called polyphenol oxidase .
When the oxygen is introduce to the injured fruit tissue, there will be conversion of phenolic compound to o-quionones in the presence of poly phenolic oxidase enzyme, colourless to brown coloured secondary product.
If you have read How Cells Work, you know that all cells contain thousands of enzymes. These enzymes do all of the work necessary for the cell to live its life. According to this article, the actual mechanism that causes browning in apples and potatoes involves an enzyme called polyphenol oxidase, also known as tyrosinase
When you eat apples or bananas, or when peeling potatoes or eggplant, the color of the fruit and vegetables becomes brown and sometimes "changes to black color, the reason is due to oxidation of phenolic compounds in the fruit under the action of an enzyme called polyphenol oxidase .
In fact, brown not black, this phenomenon is known as enzymatic browning, due to the oxydation of polyphenols compounds by oxygen under an enzymatic activity of ppo.
When peeling potatoes, or eggplant or apples etc. becomes black due to oxidation of phenolic compounds and also it is refereed enzymatic browning.
Eggplant also contains a chemical called salicylate, which is an ingredient in aspirin. This means people with an aspirin allergy or salicylate sensitivity may also be more likely to develop an eggplant allergy or intolerance to too much salicylate.
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