Why Do Apples Turn Brown?

Why do apples turn brown after you cut them, or when they rot? Basically for the same reason that human hair, eyes and skin is brown, too. Not that we're calling you rotten. Quick Questions explains!
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[@AlltimeConspiracies]

Really interesting. The moral of the story is eat apples whole!

[@EpiKOriainFT9]

or real fast

[@TheMantisShrimp]

Alltime, how good are you at football?

[@OOchriOO]

EpiKOriainFT9 well you see, if you slice an apple in half, then you eat the two parts real fast, you basically ate the whole apple...

[@crojonphoenix]

EpiKOriainFT9 or use something that will protect from oxidizing.. like lemon juice :o

[@woodfur00]

ZiQi Wei It's a metaphor.

[@SamHackenson]

So... you're telling me my apple gets TAN when I leave it in the air???

[@BANNS007FN]

Ha

[@curaxu]

why do we have fingernails actually? i mean, they make for pathetic claws...

[@thief9001]

They're vestigial, something we don't use anymore, but it's really a pain to un-put something on your body, so we just hang onto it. Also they make so good for scratching our delicate delicate skin for having stuff that's itchy!

[@kiitttenzuzu7600]

Actually we do still use them. They evolved to back padding on our soft fingers so we can gently hold very fragile fruits such as berries without popping them or dropping them. Our earliest ancestors evolved to have flatter and flatter claws as to better hold onto very fragile fruit. We still use our fingernails to help us grip things. Our toenails, however, don't serve much of a purpose since we can no longer use them to grip things. Other primates, however, can. And their toenails do therefore serve a good purpose.

[@thief9001]

Skit Terbu Top explanation!

[@cpob2013]

Clearly you've never been slapped by a woman.

[@nick11crafter]

Skit Terbu The toenails do serve the purpose of helping toe balance by adding pressure to the toe causing you muscles to not need to work as hard when attempting to balance.

[@Raattis]

"That apple is gonna be so safe." tears me up every time.

[@reverendmothercheryl2276]

To prevent the polyphenoloxidase reaction, the application of a mild acid, such as lemon juice to the cut surface of the fruit will hinder oxidation process for a couple of hours. This is also a way to keep your freshly made guacamole from turning grey before you can serve it to your party guests. Lemon juice also enhances the flavor.

[@Silverizael]

Not everyone likes the taste of lemon juice though, like me.

[@reverendmothercheryl2276]

Silverizael Very true, and I fully understand. I'm actually adverse to the taste of lemon juice myself. Also, my stomach rebels against acidic foods with some painful results. In my culinary training (my step-father was a chef), I learned that a little goes a long way. It's easy to over do it, but the right balance makes the lemon juice undetectable. Yes, I know, I had a good teacher, but I still had to experiment to get it right. The alternative is apple cider vinegar for apples, but it still can be over-done. Try it, but go lightly. You might be surprised!

[@Silverizael]

Charuko Nakamachi I prefer arctic apples, since you don't have to deal with browning with them. It's simpler.

[@reverendmothercheryl2276]

Silverizael Hmm... I've never tried them. They don't seem to be common where I live. If I find them I will give them a try. Thanks.

[@Silverizael]

Charuko Nakamachi There's only one company that sells them, I think, of the same name.

[@KrisWingfield]

I really like these. I used to skip them because I knew the answer already (oxidation causes browning, bubbles make joints pop), but when I watch them I find out more than I already knew; like how oxidation actually turns it brown or how those bubbles in our joints are created. These videos take me deeper into what I want to know. And that's what science and learning are all about!

[@amanatee27]

This is one of my favorite episodes so far! I thought the answer would be mundane, but it's really interesting!

[@dnatsrednUouYoD]

So... The apple is still alive when I eat it!!!! IM A MONSTER! ;)

[@leotamer5]

***** When you think about it, domesticated plants got it made. I mean, we literally go out of our way so their species can continue to live purely for food and pleasure even though we can get food from other sources.

[@ItsAustinSea]

***** yes apples do exist in order to be eaten, but the seeds however will not gestate unless they have passed through the digestive tract of an animal. So unless you have a machine that can perform the same chemical reactions as your stomach to the seeds, you will need to eat the seeds yourself. Problem is, apple seeds contain trace amounts of naturally occurring cyanide (A deadly poison to humans) so eating large quantities would prove harmful if not deadly;)

[@nickingram2380]

"That Apple is gonna be so safe"

[@danigurl950]

that made me laugh so much

[@Savage__Banana]

It's times like this I really appreciate the internet. I can be curious about something as unimpactful to my day as a browning apple and get a scientific explanation. Love it!

[@Lornda]

daily shows for my post daily education, love these guys

[@PaigeyBabexo]

I love when Michael does the videos! Very interesting video.

[@user-me8ix9lc3u]

This guy's great at these!!

[@emmatimewell4891]

"That Apple is going to be sooo safe!" -Best quote ever!!

[@madelinestudy2049]

I have waited for this explanation my entire life.

[@kendranorman2940]

Perfect! I'll use this to kick off our big lab on how to prevent oxidation of cut apples, Brown Out!

[@RadarRaym]

Quick question: What causes the tingling sensation in your arm or legs when you cut off blood flow ?

[@Chpeler]

TL;DR at top: It's nerves getting fresh blood. When you cut off the blood flow nerves don't get any oxygen and stops fully functioning. When the blood starts to flow again, some nerves will enter a stage where they send this "tingling" or "burning" sensation to your brain, alerting you that your foot/arm needs to change position to regain blood flow. Cutting off blood for too long can leave you with serious nerve damage, and without this sensation we wouldn't be able to notice it until we tried to use the part.

[@RadarRaym]

Zupahmann But when the blood flow is cut off the limb goes numb. It's only after the blood flow has been restored you get that warning signal.

[@Chpeler]

***** Okay, let me put it this way: 1. Your limb is positioned in a way that cuts of the blood flow. 2. Limb goes numb and motor nerves can no longer transmit signal for movement, nor can there be transmitted sense of touch. Your limb will stay in this state until there is some form of movement. Nerves can't transmit any, even emergency signals, when blocked off. Once it gets blood again your arm basically goes "omg pls move me around i need oxygen".

[@RadarRaym]

Zupahmann Ah that makes sense. Thank you for taking the time to explain.

[@NotaWalrus1]

***** Zupahmann That's actually a misconception, you're not cutting blood flow when you press your limbs, that would kill the limb in minutes. I don't remember the specifics but basically pressure prevents the nerves from working properly so when they are released they freak out and starts signaling wildly. Just a nitpick.

[@randomanimeinu]

So what happens if you cut an apple in space?

[@ShadowDrakken]

you suffocate but seriously, no oxygen = no oxidizing/browning, however, the moisture in the apple will want to rapidly evaporate too, so it's not much better

[@ShadowDrakken]

Just a bit of extra info to add, most (if not all) freeze dried food manufacturers use a vacuum chamber for the freeze drying process. science.howstuffworks.com/innovation/edible-innovations/food-preservation4.htm

[@randomanimeinu]

Thanks for the answer. Freeze dried fruit is still good, at least. Still edible and wont go bad for a long time, so I'd say it's a win/win.

[@ShadowDrakken]

Well, except without freezing it first you wouldn't get freeze dried, you'd get a foamy, pulpy almost ceramic-like texture from the liquids boiling straight through the solids :)

[@randomanimeinu]

Damn. Well, I guess I would never survive in space if the world were to end.

[@TheMusiclover483]

oh michael. i love how sassy you get when you discuss apples.

[@Moonbeam143]

You know what's bad? When you take a bite out of an apple and you see a worm. You know what's worse? Seeing half a worm.

[@nadiachet724]

Apples with worm means it's all organic no pesticides, harsh chemicals..spot the worm , pick it out and eat the apple because it's safe

[@Toastmaster_5000]

this is surprisingly fascinating

[@kaitlynjohnson1223]

i have always wanted to know why this happens...thank you michael aranda!!

[@austinfehrer6574]

"All I was left with was a mouthful of disappointment."

[@recterbert]

***EPISODE SUGGESTION*** How does soap work? Why does it repel oil when its made of lard and oil? Something to do with acids and bases maybe? I've never researched it, but have always wondered.

[@RinoaL]

my macintosh is like 30 years old and it turned brown, but thats because it was in direct sunlight. :p

[@gregski711]

Correction: Melanin is not a protein like you say at 0:49. Other than that, great explanation!

[@tejasripradeep8797]

Thanku u sooo much ive been trying to understand this for a long time but ...omly now it has put some sense into my brain ...thank u sooo much

[@lilsusx2469]

Dude you really helped me for my project.

[@srpilha]

That was a particularly interesting one, well done.

[@garethhale2597]

You have Indole 5,6-quinone drawn wrong, the pair of double bonds on the six sided ring both needs to be shifted one bond to the right. the current drawing exhibits a pair of 5 bonded carbon atoms, which is so unstable we (organic chemists) don't even consider it as existing. BTW, love you guys.

[@auntmanda6157]

Sir, I cannot tell you how much I enjoy watching your qq bids. So, it's actually a bunch! However, I often have a hard time hearing you over my gamer, even with earbuds in! I really, really like them though!

[@andrewr499]

That was extremely informative and interesting. That is all.

[@ItsYaBoiRayden]

TURN BROWN FOR WHAT!

[@TungstenWu]

does squinting help you focus and see a distant object? if so why do we do it instead of some other thing and how and why does it help. if not, why not and what can help? - please see this

[@TungstenWu]

true but i want more friking specific things and facts coming from someone - else

[@firstnamelastname4752]

Tungsten Wu I recall seeing a video about this nearby... might have been a segment of a Vsauce episode?

[@TungstenWu]

right

[@MihirGore]

lucid explanation, Micheal

[@Dtownrelics2]

If I were to watch one video with this host and a video with the other host with my eyes closed. I wouldn't be able to tell them apart, there voices are so similar

[@PaulSutherlandnow]

our skin and apples are brown due to production of the same chemical. (won't spoil from this video...) so does some of our favorite flavors. WOW! Nasty brown apples and delicious brown treats, amazing connection. SciShow! One beloved effect one not so much. Awesome video.

[@MosbeckPhoto]

You can soak the cut up apple slices in cold lemon water to prevent them from turning brown. Use about 1tbs of lemon juice to 1 cup of water. You can also spray them with lemon juice, but then your apples will taste more like lemons.

[@MayaGasterMoll]

DAMN *****, on point! Also whoever wrote this vid! Loved it

[@Rustle84]

If Michael could turn up the volume of his microphone...I have to turn up the volume on his videos then a Hank video comes on AND ITS YELLING AT ME!!!...

[@angelic8632002]

Interesting, didn't know this. Thank you!

[@Poopdahoop]

This video re-sparked my love in science! Yey!

[@ahtoshkaa]

wow. that was very surprising!

[@MaxMikescrool1]

He answered a question like this explain Oxidation in a video a long time ago :3

[@ALoreMiles]

A Castle Story shirt? Awesome!

[@angelgirld]

soak apples in lemon or salt water directly after cutting to slow the browning. idk why it works, but it does.

[@missliketoeat]

thank you for the awesome food for thought!

[@AlGhoul]

Probably should have made note of how certain apples brown slower than others. I believe this is due to the acid concentration being higher and interfering with the oxidation, but it has been a long time since I took high school chem, haha. Granny Smith's take long to brown.

[@catherinenguyen5612]

You should do a follow up to this video and explain how lemon stop apples from browning

[@AlecInstant]

CASTLE STORY -best shirt ever

[@Michael-rt2tl]

Hey SciShow I was wondering if maybe you guys could consider making a KZbin channel for a higher level of educational learning? Something more of a University level, it's just that your videos are great but as learn more in other parts of my life such as school and personal learning the videos start to feel like they are more suited for a Grade 8-10 level which is disappointing since you guys make amazing videos explaining several different topics! I think John might have said this in one of the vlog brothers videos but if not I think you should consider it!

[@Mc_Vomit]

"I only wanted an apple, and now I have a mouthful of disappointment. What happened?" Nickel for every time i've heard that...

[@jpfd-2315]

When u said melanin, I thought u said melon amd I was like no I have never heard of that chemical before lol!

[@caitlinirelan5641]

Fun fact- if you put lemon juice or pineapple juice on apple slices it keeps them from browning. We had to do that in the kitchen during vbs when apple slices was part of the snacks.

[@BeCurieUs]

There is a new GMO apple that lacks the PPO so there is no browning. It is called the arctic apple, and I totally can't wait for them!

[@ssholum]

Use vitamin C powder or lemon juice to prevent oxidation in fruit slices. It's great if you have a bunch of fruit slices that aren't about to be eaten for some reason.

[@ZeldaFreak4by2]

Good show by the way! SciShow is a lot of good information daily! I did want to ask of Parkinson's disease, what are effects to the brain? Why is the disease more likely in men than in women? Where did Parkinson's come from?

[@Medevildragonman]

I love the castle story shirt

[@danielsoloboyleon9002]

👌thanks no wonder why my apples 🍎 change color quick to brown didn’t know the theory behind that’s 👌

[@transce]

i finally subbabled

[@Miphnificent]

As an arachnid hobbyist who works primarily with scorpions, I have to wonder the following: Why do scorpions fluoresce? It's debated among scorpiologists, and some species of Chaerilus and Megacormus do not fluoresce under UV light whatsoever, but instead look very splotchy. One arachnologist I converse with on a daily basis suggests that it may have to do with UV protection in the Silurian, however it's still debatable. Only asking in the event that anyone here/scishow has more access to information regarding this than I.

[@madelaineparry5386]

Ya know, if you slice an apple and don't finish it, my dad taught me this cool trick: put the slices in a ziplock bag and squeeze in a little lemon juice to keep them from turning brown. Awesome for packing lunch!

[@quantumautomata1368]

Brownies are brown because god said so. apples turn brown because they like brownies, In short apples want to be like brownies

[@HShango]

lol you can't be serious

[@tubedude9311]

god doesn't exist

[@tomshraderd4915]

Herve Shango I believe it's called a "joke" in technical terms. It's not that hard to recognize!

[@ilikegearsofwar3]

tubedude9311 gods* don't exist. They are contradictory to logic.

[@YouJustGotGerrowned]

WOULD YOU LOOK AT THIS Scishow episode Someone mentions god and/or religion Three(and likely more to come) people jump in to inform everyone that it's all made up, even though the original post obviously a joke, such that humans with only half a brain should be able to recognize it as such!

[@MrSubet]

sci show is epic

[@savannah4439]

I cut into an apple once and the slicer went straight through with like no resistance and it was rotten-y brown and liquid-y in the middle. The core fell apart when I touched it, but the apple looked perfectly fine on the outside. I will never bite into an apple again.

[@SignedAdam]

very cool, thanks

[@insederec]

Sweet Castle Story shirt.

[@LolLol-ce9ch]

Thx for telling me now I know what to do for my since fair project

[@SLM6463]

cool i didnt know that and im doing a project for it at school ty for the help

[@jsarmentovasconcelos]

Suggestion for Q&A red leaves plants. There are plants who are not green, they are red. No clorifile?

[@95CARMEN]

awesome!

[@elanianiyvwia8687]

If you coat the apple slices with citrus juices it stops them from turning brown.

[@gemmag7746]

I think there's something wrong with the structures of Dopa Quinone, Dopachrome and indole 5,6-Quinone in the scheme - you have five bonds to some of the carbons in the ring. Thanks for the video, I've always wondered about this!

[@blablibliblu514]

I never noticed a difference in taste between "fresh" and browned apples.

[@Edgewalker001]

Don't know if anyone said this already, but like most enzymes PPO is kind of picky about its surroundings. It does not like changes in pH and as a result, if you drip some lemon or other citrus fruit juice on your apple after you cut it, this process will be halted.

[@anzealot]

who the fuck eats half an apple?

[@Chpeler]

Someone who doesn't want to eat an entire apple.

[@sandeepmurthy3512]

Steve Jobs.... he just took a bite.

[@Someone-eu1ns]

Sandeep Murthy Truth.

[@affenonkel]

To quote John Green, "Imagine apples complexly."

[@aeolist-jess]

wait so then why do we enjoy the taste of the oxidation reaction in coffee, tea, and those other things mentioned, but not in apples? (aha im probably thinking too hard about this)

[@2c9s]

A trick I've seen in many kitchens: if you dip apples in salt water soon after cutting them, they don't brown as easily.

[@blitzwaffe]

I actually like it when apples turn slightly brown :/ I mean I wouldn't eat one after it's been lying around all day but I'm fine with one that's changed color a bit. I must be the only one like this :(

[@thief9001]

It's nothing to be upset about, embrace your differences, and use them to KILL YOUR ENEMIES.

[@thief9001]

kazooga1234 Did you skip the Healthcare Triage explaining how no?

[@blitzwaffe]

thief9001 Err how did a comment about apples turning brown turn into a discussion about killing enemies and GMOs?

[@twoedgedmind]

kazooga1234 because China is a dictatorship. And wants to separate itself from the rest of the world. by your logic, KZbin and Facebook are deadly.

[@thief9001]

kazooga1234 because letting cheap American goods into their market would undermine Chinese farmers. It's why sometimes it's better to ban American goods, and have producers locally make it. If you sell American grown food for cheap somewhere, and then it drives all the farmers out of business. And they change their land to growing a different food, then if America either doesn't produce as much or they decide to not sell to you anymore, you are at a greatly increased risk of food shortage. That's why China doesn't buy American apples. But it doesn't matter because you're so deeply entrenched in your belief I could provide you with every reason and source and you would still probably think that I biased and wrong. But it's all good, don't buy American if you don't want to, I won't stop ya bud.

[@Silverizael]

This is why the Arctic Apple is awesome, no browning to worry about.

[@Velociter]

Honeycrisp apples are so good. Juicy, sweet, tart, firm, and mouth watering.

[@gmkaufman11]

you should make a video evaluating the authenticity of the phrase, "dirt don't hurt". Can dirt be harmful and if so how?

[@konstantingemov6441]

Nothing to do with apples but, where did you buy the shirt?? Its awesome!!

[@MsSilentH]

Bananas brown super fast too. I make a banana smoothie and minutes later part of the smoothie starts turning brown. :( lemon juice helps keep the color of apple slices but just eat the whole apple, your body will thank you.

[@almirhatkic8241]

I like this guy

[@TheCaptainRaccoon]

"Mouthful of Disappointment" That was my nickname in high school

[@FrozenLemur]

I know the solution! We all need to become world record apple speed eaters. Simple.

[@jonathanseamon9864]

Note that the correct way to prevent this is Blanching.

[@paulwhite3260]

The graphic where phenoloxidase transforms tyrosine into melanin has a graphical typo in the Dopa quinone, Dopachrome and Indole-5,6-quinone structures. In each of these, the orthoquinone has two Texas carbons (carbon with 5-bonds) for the ketone carbons. Makes my poor chemist heart break SciShow! :(

[@hansbrandt6471]

Mind blown! I fucken love this show!

[@MunawarTirurt]

You could add some animated videos or other videos in this from other KZbin videos which will be a great thing....:)

[@joesteele1352]

I would have thought they would have mentioned the recently announced Arctic Apple which was genetically modified to never turn brown.

[@siramea]

How does lemon juice stop cut apples turning brown?

[@DaveMeowington]

All this time, all this time i was... drinking roasted melanin? NOOOOOOOOOO!!!!!

[@MinecraftMultiTuts]

Why do stretches feel sooooo good? :D!

[@David-ld3ts]

How does an airplane wing work? How are fighter jets able to fly upside down or right side up?

[@sergeantsilverheart]

SciShow, why isn't my applesauce brown?

[@TiberiusIan]

What is the whole process that takes place when a person injures/cuts himself? I would like to know hot the human body reacts to different injuries, but I failed to find some detailed info. This could be a good scishow episode. Thanks!

[@0oOSTFUOo0]

The surface of the apple won't oxidate as quickly if you use a really sharp blade to cut it :)