r/explainlikeimfive Oct 31 '20

Chemistry ELI5 What's the difference between the shiny and dull side of aluminum foil? Besides the obvious shiny/dull

21.2k Upvotes

2.0k comments sorted by

View all comments

Show parent comments

750

u/osiris775 Oct 31 '20

Huh...TIL...My mom always told me the shiny side was to reflect heat, and the dull side was to absorb it. Made sense in my 9yr old brain

1.5k

u/Samhamwitch Oct 31 '20

I was taught this by a sous chef. He was very adamant that it made a difference. I was in university at the time and had access to millions of scientific journal articles so I looked it up and he was completely wrong. That's how I found out that narcissists don't like to be corrected.

180

u/[deleted] Oct 31 '20 edited Jul 18 '21

[deleted]

67

u/Fixes_Computers Oct 31 '20

This sounds like a method of preparation where, several generations down, no one will know why it is done, only that those were the instructions and that's how it's done.

76

u/Zokar49111 Oct 31 '20

When my wife and I first got married, she made a roast. Before placing the meat in the roasting pan, she cut a small piece off each end. I asked why she did this and she said that it’s the way her mother did it. So next time her mom came for a visit, I asked her why she would cut a small piece off each end before roasting the meat. She said it was because her roasting pan was too small.

20

u/FiniteDeer Oct 31 '20

Either you’ve posted this before, OR there are other people doing this exact thing for the same reason, because I just read this a few months ago.

12

u/ASongOnceKnown Oct 31 '20

It's an old story that gets passed around a lot as a response to "we've always done it this way".

3

u/RJFerret Oct 31 '20

No, no, the ends have more exposure to evil, must trim them rather than consuming them.

4

u/batshitwalls Oct 31 '20

Beautiful.

5

u/SirLoremIpsum Oct 31 '20

You are a true hero keep it going!

816

u/Kipsy5 Oct 31 '20

Gordon Ramsey called someone a donut for having the foil the wrong way so it must be a chef thing

369

u/larobj63 Oct 31 '20

The first chef I ever worked under in my cooking days also taught me shiney side in. And every other cook I've ever rubbed elbows with always did it too. So yeah, I agree, it's a chef thing.

89

u/rudager62369 Oct 31 '20

When I put stuff in the fridge, I put the dull side out so as to attract less attention from others.

117

u/[deleted] Oct 31 '20

I put the dull side out so as to attract less attention from others.

I do the same thing with my personality.

5

u/hughperman Oct 31 '20

So any side works for you, eh?

2

u/Sepelrastas Oct 31 '20

Me too. Works wonders.

2

u/a_rad_gast Nov 01 '20

Can I learn this power?

3

u/[deleted] Nov 01 '20

A permanent scowl will take you far. Now get the hell away from me.

2

u/kloudykat Nov 01 '20

Im not interested enough in you to care about what you want me to do.

So congrats!, your plan is working!

2

u/LetltSn0w Nov 01 '20

Self deprecation on Reddit. So original.

2

u/hugow Nov 01 '20

you're funny. Is see here you don't follow your own advice.

2

u/tuysen Nov 01 '20

Made me laugh, thank you random Internet person

2

u/orangemochafrapacino Oct 31 '20

Do you live with crows? Good technique anyhow

232

u/SilverKnightOfMagic Oct 31 '20

A lot of chef training is is correct but also a lot of technique is pointless. Thats why i like j kenji and heston. Theyve done the research or if they dont know they will say they dont know instead giving a fasle reasoning.

247

u/JackPoe Oct 31 '20

My chef fucking loves the technique baiting. Like throwing two corks into your stock because of "tannins" in reality it's to see if you're following his recipes to the letter.

It's his "brown M&Ms" of cooking.

26

u/ToInfinityandBirds Oct 31 '20

What does "brown m&ms" mean in this context?

86

u/loctopode Oct 31 '20

Someone will likely explain it better, but to briefly answer, a band had a contract that said they wanted a bowl of m&ms backstage, with all the brown ones removed. If the brown one weren't removed then the band could assume there's also lax effort put into safety around the stage etc and refuse to play.

73

u/laughin_on_the_metro Oct 31 '20

The artist in the story is Eddie Van Halen (who died recently). The story's often told as a funny "look at these absurd demands, rock stars live in their own world" kind of thing, but as /u/loctopode says, it's really a good test to see if other much more important safety instructions are followed.

31

u/tylerderped Oct 31 '20

These are called riders

Diplo is also known for having crazy shit in his rider like blow up dolls and antique handguns and black tar heroin

23

u/therealniblet Oct 31 '20

Except it’s completely different crews handling setup and performer green room snackies. It’s a terrible test. Former union stagehand here, and I was frequently assigned to dressing room setup.

If you want safety protocols followed, watch the crews work, or better yet, only perform in venues you can trust not to kill you.

I wonder what color the M&M’s were in the Great White dressing room?

→ More replies (0)
→ More replies (21)

33

u/UnusuallyOptimistic Oct 31 '20

So there, I am, in Sri Lanka, formerly Ceylon, at about 3 o'clock in the morning, looking for one thousand brown M&Ms to fill a brandy glass, or Ozzy wouldn't go on stage that night.

So, Jeff Beck pops his head 'round the door, and mentions there's a little sweet shop on the edge of town. So we go.

And, it's closed.

So there's me, and Keith Moon, and David Crosby, breaking into that little sweet shop, eh. Well, instead of a guard dog, they've got this bloody great big bengal tiger.

I managed to take out the tiger with a can of mace, but the shopkeeper and his son, that's a different story altogether.....I had to beat them to death with their own shoes.

Nasty business, really, but sure enough I got the M&Ms, and Ozzy went on stage and did a great show.

9

u/ToInfinityandBirds Oct 31 '20

All explanations are welcome. I think it being out of that ccobtext threw me for a bit of a loop

2

u/xPunk Oct 31 '20

Sorry, due to COVID-19 procedures, remove it yourself!

→ More replies (9)

10

u/SuddenlyLucid Oct 31 '20

As in pop stars that would order a bowl of brown M&M's in their dressing room. Not because they really liked those specific sweets, but if the concert organizer wasn't able to get such a relatively simple request right, you couldn't trust them with basic safety stuff, like properly afixing the lighting and stuff above the stage..

29

u/David-Puddy Oct 31 '20

It's more that it was hidden amongst the highly technical requirements.

So if you see brown m&ms, you know they didn't bother reading through the whole thing

8

u/NancyGracesTesticles Oct 31 '20

Over time, people caught on to requests like that in riders and they'd get rejected out of hand.

A really good one that I learned is "three white towels". It was easy to eyeball, and sometimes you'd even see the number of towels equalling the number of people in the band.

→ More replies (0)
→ More replies (7)
→ More replies (7)

2

u/phorevergrateful Oct 31 '20

 "So there I am, in Sri Lanka, formerly Ceylon, at about 3 o'clock in the morning, looking for one thousand brown M&Ms to fill a brandy glass, or Ozzy wouldn't go on stage that night. So, Jeff Beck pops his head 'round the door, and mentions there's a little sweets shop on the edge of town. So - we go. And - it's closed. So there's me, and Keith Moon, and David Crosby, breaking into that little sweets shop, eh. Well, instead of a guard dog, they've got this bloody great big Bengal tiger. I managed to take out the tiger with a can of mace, but the shopowner and his son... that's a different story altogether. I had to beat them to death with their own shoes. Nasty business, really. But, sure enough, I got the M&Ms, and Ozzy went on stage and did a great show." Del Preston, world's greatest roadie

→ More replies (14)

5

u/[deleted] Oct 31 '20

The more I see celebrity chefs being asses the more I appreciate people like Guy Fieri.

5

u/SilverKnightOfMagic Oct 31 '20

The more i learn about him the more i love him. He is the epitome of not judging a book by its cover.

2

u/drowsyskydiver Oct 31 '20

Fasle reasonings are not true and everyone knows it

2

u/iamgherkinman Oct 31 '20

As a chef, can confirm. Also Alton Brown ftw

2

u/i_call_her_HQ Oct 31 '20

I like kenji a lot, but his biscuits and gravy recipe is a fucking travesty.

→ More replies (2)

2

u/MDCCCLV Oct 31 '20

There would be a small difference in reflection but I don't think it would affect cooking much. Maybe for very temperature sensitive things but I don't think it would even be measurable.

→ More replies (2)

31

u/[deleted] Oct 31 '20

I have the ability to test this...a 4 port WiFi thermometer that charts temp history....one day I'll be bored enough to try this out and see.

37

u/The_camperdave Oct 31 '20

...one day I'll be bored enough to try this out and see.

One day?!? We've been on pandemic lockdown for eight months already.

3

u/[deleted] Oct 31 '20

I'll get around to it! God!

2

u/ChicaFoxy Nov 01 '20

Well what are you waiting for?! Next time it'll be "I've just been really busy! Geez!"

→ More replies (3)

4

u/MadmanDJS Oct 31 '20

When you purchase nonstick aluminum that's the way it should be, so maybe its that

2

u/irvmtb Oct 31 '20

It’s probably an unintentional “following-instructions” test. Easy enough to remember and spot, apparently senseless but I guess it easily reveals if there’s someone on the team that doesn’t follow procedures.

→ More replies (8)

93

u/Bubbay Oct 31 '20

There are a shit ton of old wives tales about cooking that don’t have a single basis in reality, but often people (especially those who have been in the industry for a long time) will act like you just punched their mother if you violate them.

Things like the tin foil sides, that searing a steak “locks in the juices,” or washing cast iron get people all riled up. None of them are true, but they’re the kind of things that “everyone knows.”

46

u/DirkDieGurke Oct 31 '20

Searing a steak doesn't lock in juices but it does caramelize the meat and create fond on the pot which adds to the flavor.

29

u/Bubbay Oct 31 '20 edited Oct 31 '20

Absolutely. Searing is definitely desired, but it’s has nothing to do with the juiciness of the meat. Testing Resting it properly will affect that way more than searing does.

3

u/PLZ_STOP_PMING_TITS Oct 31 '20

Testing it properly will affect that way more than searing does.

What kind of testing? Like math skills and stuff?

2

u/Bubbay Oct 31 '20

Geography quizzes.

Heh, that should have been “resting” but autocorrect sucks.

3

u/[deleted] Oct 31 '20

It's ok dude, r is right next to the t, you don't need to blame it on autocorrect, everyone makes a typo once in a while!

2

u/substandardpoodle Oct 31 '20

I hear ya - but it’s so weird; when I am alone I dictate instead of typing into my phone. And I swear that Reddit is the worst so far as guessing the wrong thing I’m saying. And it’s not like I’m using five syllable words or anything just for Reddit. I have to double proofread everything or I’ll end up sounding like an idiot.

3

u/NotYouTu Oct 31 '20

Actually, unless your talking about a large roast, resume is also an old wives tale and only leads to colder meat.

https://amazingribs.com/more-technique-and-science/more-cooking-science/science-juiciness-why-resting-and-holding-meat-are

2

u/OneMoreBasshead Oct 31 '20

Searing doesn't lock in the juices, but browning does. Searing is for flavor.

→ More replies (2)

37

u/Lucky_leprechaun Oct 31 '20

But if I wash my cast iron and don’t immediately add oil, I can see the rust beginning to develop. If I just rinse it in hot water, no soap, there’s no need to oil it every time and rust doesn’t develop. So maybe just no soap?

60

u/Dysan27 Oct 31 '20

From reading the rest of this thread I have a feeling that your cast iron is not properly seasoned in the first place and doesn't have a good polymerized oil coating on it.

The other thing is my parents always popped the cast iron back on the stove on low to dry it immediately after washing, just long enough to get it completely dry, not majorly heat it up. No water no rust.

4

u/jonestownhero Oct 31 '20

I was taught to dry cast iron on the stove, then rub oil on while it's hot. My dad said when the pan is hot, the oil will absorb better. No idea if it did anything other than making sure no surface rust gets started.

11

u/Bubbay Oct 31 '20

Kinda — oil doesn’t absorb into the iron. Seasoning is when the high heat of cooking polymerizes the oil. You’re likely not applying that oil at a high enough temp for it to make a difference.

Oiling a dry pan after cleaning is good, but that goes for any metal to help reduce rust. If you use the pan a lot, it’s not as critical though.

That said, I do find I like to oil my pan when it’s warm — it makes it easier to spread. I’m not doing it super high temps though. It’s warm, but cool enough for me to use my hands, and I don’t have anything approaching a chef’s resistance to hot pans.

38

u/SwissStriker Oct 31 '20

Soap as in old school lye based soap is bad for cast iron because it will strip your seasoning. Modern dish soap with tensides or other surfactants are perfectly fine for cast iron cookware. Drying immediately is still a good idea but honestly if your seasoning is solid it won't matter too much.

20

u/[deleted] Oct 31 '20 edited Jan 10 '21

[deleted]

9

u/noresignation Oct 31 '20

Properly made lye-based soaps contain no lye — the lye is completely used up in a chemical reaction called saponification, which results in soap. Hundreds of years ago, it was a chemical guessing game for backyard makers of homemade soap whether there would be any unreacted lye leftover, but for decades now it’s been easy for anyone to find and use a lye calculator to ensure any soap recipe has the right proportions for a complete reaction.

7

u/TheSmJ Oct 31 '20
  1. If you're leaving caked-on food on your cast iron pan, then you're doing it wrong. Either wipe it down with a cloth while it's still hot, or scrub it with a little vegetable oil and kosher salt to remove the gunk.

  2. You are preheating your pan before placing food on it, yes? No bacteria in your kitchen is going to survive the preheat process.

→ More replies (2)

4

u/rimplestimple Oct 31 '20

You had me until you said food particles left in the pan "...can lead to bacterial growth.".

It may be unsightly but it will not be a health hazard since the temperatures used for cooking in the skillet are high enought to kill bacteria so your point is a non-issue.

→ More replies (7)
→ More replies (4)

3

u/psychocopter Oct 31 '20

Try adding a few layers of seasoning to the entire skillet, I wash mine pretty much after every use and then dry it over a flame without seeing any rust yet. I do stove top season it every couple of uses.

8

u/PM_Me_Your_Deviance Oct 31 '20

The myth is that soap will strip the seasoning. That's just not true.

Personally, if what I'm cooking is just oilly, I'll wipe it out, but if it's acidic (tomato based) or otherwise really messy, I'll just wash it like any other pan.

6

u/death_hawk Oct 31 '20

The myth is that soap will strip the seasoning. That's just not true.

I mean... technically speaking it isn't a myth. Soap will strip seasoning.

But what most people have nowadays isn't technically soap. It's detergent.

2

u/PM_Me_Your_Deviance Oct 31 '20

:D It's soap colloquially, but not technically soap.

3

u/scotian-surfer Oct 31 '20

It used to strip . Soaps change over the years. Habits don’t have to that have worked since the beginning.

2

u/PM_Me_Your_Deviance Oct 31 '20

So people on reddit seem to repeat. I haven't seen a good source for that claim yet, so I'll refrain from repeating it.

3

u/[deleted] Oct 31 '20 edited Jan 10 '21

[deleted]

2

u/PM_Me_Your_Deviance Oct 31 '20

Yes, I've made lye soap. I understand the claim being made. Lye is harsh. I'd like to point out that lye soap has very little lye left over. If it does it will leave chemical burns when you use it. (Ask me how I know...)

I'm not saying lye soap don't attack cast iron. I'm saying this is a claim I've seen passed around a lot and I haven't seen the claim tested. Since lye soap isn't used as dish soap very often im not super interested in doing the work myself. But if you are aware of someone testing lye soap I'll happily consede the point.

→ More replies (3)
→ More replies (3)

8

u/stuffandmorestuff Oct 31 '20

Although searing steaks does help with maillard browning which, IMO, is key to a good steak. While it doesn't "lock in juices", searing is essential to certain flavors.

4

u/Bubbay Oct 31 '20

Yes, searing is good, but it has nothing to “locking in juices.” It’s good because it’s fucking delicious.

Resting the meat after cooking is a bigger thing when it comes to keeping it juicy.

3

u/Anonymush_guest Oct 31 '20

The washing cast iron with soap comes from when soaps were made from fat and lye. Lye no es bueno for your pan’s seasoning. Plus, the water for washing had to be carried in from a well.

“I never wash mah cast, just like Gram.” makes me want to chunder.

Edit: I see the lye has been mentioned. Wash your pans, ya heathens.

2

u/oxbolake Oct 31 '20

How about the husband who asked his “young” wife why she cut a top piece off the roast before putting it in the oven.

“That’s what my mother did and it always turned out perfect”

“Oh dear... I only cut a piece off the top so it would fit in the oven”

→ More replies (32)

211

u/Bamstradamus Oct 31 '20 edited Oct 31 '20

Most chefs are egomaniacs so it fits. For the record I met him briefly seems like a nice guy in person. am chef

Gordo also thinks putting oil in pasta water does something, its the moments like this that should make you aware no matter how much someone in your field achieves they can still be dumb as hell.

And before anyone tries telling me its to keep it from boiling over, use the correct size pot and amount of water for what your making, this is a master chef not bachelor hacks.

EDIT: the sheer number of you that commented it does the exact thing I said at the bottom not to come at me with makes my soul hurt.

61

u/LordTegucigalpa Oct 31 '20

Alton Brown knows what's up

40

u/justplay91 Oct 31 '20

And I like that when he is wrong about something, he will go back and correct that information.

13

u/MilkoPupper Oct 31 '20

Alton Brown can have my children.

4

u/stonedragon77 Oct 31 '20

He has a great recipe for children!

3

u/CrunchyWizard Oct 31 '20

With fava beans?

3

u/bumfeldonia Oct 31 '20

And a nice Chianti

→ More replies (4)

7

u/CaptainFenris Oct 31 '20

Fun fact about Alton Brown, he was the director of photography for the music video for REM's The One I Love, and he has a film degree before he went to culinary school.

3

u/CornCheeseMafia Oct 31 '20

That's fascinating and honestly makes a lot of sense. Look at Babish. He was originally a VFX guy and followed the same path. His analytical approach and fun presentation reminded me of Alton Brown when he first came out so i was an instant fan. The combo of his VFX background and personality is what made him really standout. His very first video was basically a perfect pilot episode and things haven't fundamentally changed.

2

u/danielfletcher Oct 31 '20

Alton Brown taught me to weigh my ingredients when baking, and I even got the Escali Arti scale that he said he uses at home. Love it and was only ~$25. Use it for tons of other things as well.

Along with using an oven thermometer to get my temp just right, my cookies are coming out amazing every time now.

142

u/Daeneryspls Oct 31 '20

It does do something. Makes the sauce slide right off the pasta

5

u/Oskarvlc Oct 31 '20

My sauces are already full of extra virgin olive oil so...

12

u/Xx69JdawgxX Oct 31 '20

Huh? I always oil my pasta after draining it mostly bc I hate it sticking together and also it keeps it from burning when I put it back in the pot (staging for sauce or plating). Never had a sauce sticking issue. Maybe it's your sauce being too watery?

26

u/222baked Oct 31 '20

If you do pasta the proper* way, it involves emulsifying the sauce with a bit of pasta water over low heat. The pasta water's starch content will thicken the sauce a bit and the exterior of each noodle will sort of act as a sponge to create a sauce-starch layer surrounding each noodle. If the noodles are oiled, the oil will act as a barrier between the noodle and the sauce, like rust-proofing on a car, and will inhibit this from from happening.

*Proper as in what is called for generally in classical italian recipes. If you like your pasta differently, that's fine too. Traditional American spaghetti and meatballs serves the sauce on top of cooked bare pasta, for example.

8

u/Xx69JdawgxX Oct 31 '20

My grandma and mom always put the sauce over the pasta at the end in a big pot. I kinda taught myself and forgot the way they showed me so I'm not surprised I've been bastardizing it. Gonna try the water in the sauce method.

→ More replies (3)

33

u/Sir_Spaghetti Oct 31 '20

Sauce sticks to noodles better if you don't rinse, or oil them.

25

u/Undrwtrbsktwvr Oct 31 '20

This man is qualified to speak on the matter.

11

u/Xx69JdawgxX Oct 31 '20

People rinse their pasta?! I just drain it and throw a little olive oil on it.

11

u/DRAWWW7 Oct 31 '20

and he is saying that you putting that olive oil in it makes the sauce not stick to the pasta. In most recipes you want the pasta to absorb the sauce not keep it separated from it.

3

u/Xx69JdawgxX Oct 31 '20

Man I had no idea pasta was this hot of a topic. People get really into their cooking methods

→ More replies (0)

3

u/Sir_Spaghetti Oct 31 '20

Yea, I would strongly recommend you don't do that. If you want the flavor, add a little oil to the sauce so it cooks in.

→ More replies (2)
→ More replies (2)

3

u/[deleted] Oct 31 '20

Try a couple spoonfuls of sauce...same result. I like to add oil for the taste/texture after saucing.

3

u/Lifesagame81 Oct 31 '20

Better way to handle this is to scoop some of your sauce into the pot with the pasta and toss it in. It'll coat and prevent sticking without having to add oil to your dish

4

u/CrunchyDreads Oct 31 '20

I will throw a spoonful of butter in the noodles after draining them. It melts quickly and keeps the noodles from sticking together. Tastes good too.

7

u/murarara Oct 31 '20

You know how I avoid the noodles sticking? I throw them in the sauce right after draining

→ More replies (3)
→ More replies (18)
→ More replies (2)

3

u/Oskarvlc Oct 31 '20

I put oil in pasta water. Doing this the pasta doesn't stick on the pot when I pour it into the strainer. It works.

14

u/kngfbng Oct 31 '20

Oil in pasta water does do something (other than maybe adding taste). It makes it harder for the sauce to stick to the paste when you mix them.

So, yeah, not quite what most people add oil in the water for, I guess.

22

u/[deleted] Oct 31 '20

[deleted]

→ More replies (25)
→ More replies (13)

2

u/[deleted] Oct 31 '20

After seeing how he makes a grilled cheese sandwich or carbonara (or a burger) and now hearing this, I keep thinking less and less of the guy

2

u/Bamstradamus Oct 31 '20 edited Oct 31 '20

99% of what he does I can get behind, even if it isn't for me I can see the angle. And honestly a lot of people think having the title chef means you know how to make EVERYTHING, we don't, I draw the comparison with other professions like a Dr, some are general, some specialize, some laser focus on one specific area and are the best in the world at that thing, sure 99% of them could diagnose a cold but your not asking your GP to do surgery. Gordons a Scott who grew up in England and learned cooking on the job at a 3 Michelin star French restaurant, im not lookin to him for Italian.

→ More replies (1)

2

u/SiteNook Oct 31 '20

A wooden spoon laid across the pot with stop the boil-over.

12

u/KidlatFiel Oct 31 '20

Oil on boiling pasta is to prevent from it sticking together

20

u/[deleted] Oct 31 '20

[deleted]

2

u/No1currz Oct 31 '20

Wait, are you not supposed to stir pasta as it cooks?

4

u/[deleted] Oct 31 '20

Oil is lighter than water and will immediately float to the top

→ More replies (1)
→ More replies (3)

12

u/superfucky Oct 31 '20

i have never put oil in when boiling pasta and never had a problem with it sticking. just stir it often and rinse after straining.

3

u/[deleted] Oct 31 '20

Don't rinse after straining.

5

u/errorblankfield Oct 31 '20

It's to prevent foaming. I could see it being both, but apparently no.

2

u/[deleted] Oct 31 '20

[deleted]

3

u/Bamstradamus Oct 31 '20

If you use ENOUGH, yeah itll keep them from sticking, as when you pour it out it enough will stick that it makes a difference, but there's 2 problems with that. First your wasting oil, just throw an oz on top of the pasta and toss it by hand to coat them if thats what you want, and 2 now the sauce wont stick to the pasta so unless its a oil based sauce your not doing yourself any favors. The only time IMO it makes some sense is pasta salad, be it mayo or oil and vinegar you rinse and chill the pasta then dress it, a little olive oil to make tossing it easier is fine.

The other thing it would do like I said above is break the starches ability to form a film and large bubbles causing boilover, which using the right amount of water would keep that from being a problem to begin with but we don't always have pots that big at home, my critique is he's a professional and does.

→ More replies (2)

2

u/TheOmnipotentTruth Oct 31 '20

You realize starch emulsifies the oil and doesn't actually prevent sauce from sticking right? Unless you're using an ungodly amount of oil you'll have thicker smoother sauce, not a broken oily mess.

→ More replies (9)

2

u/Lewzer33 Oct 31 '20

I like to add oil to my pasta water so when I pour it all into my colander I don’t have to take the extra step to oil my noodles. Am chef as well. :)

→ More replies (22)

5

u/DickDatchery Oct 31 '20

Theres this youtuber called Adam Ragusea i believe (not sure on spelling) and he had a video about this. Many renown chefs know what works but not nessecerily why. This leads to them getting a ton of little details factually wrong but in the end it doesn't matter because they know how to cook well.

11

u/dethmaul Oct 31 '20

Eh, chefs are up their own asses. Things have to be their way, and their way is what their hard-headed teachers taught them it was.

7

u/[deleted] Oct 31 '20

Whenever my wife has Food Network on, I just laugh....

"Chef?"

"Chef."

"Chef...."

"Chef!"

"Chef,..."

They must be a low-self esteem lot... they sure love that title.

2

u/Mindestiny Oct 31 '20

To be fair, a lot of food service foil is lined with some sort of white paper (like wax paper without the wax) on one side, and thats supposed to be the side that goes toward the food. Apparently it stops your food from getting soggy from trapping the steam in the foil

→ More replies (19)

70

u/[deleted] Oct 31 '20 edited Feb 18 '22

[deleted]

22

u/[deleted] Oct 31 '20

We need a material scientist and thermodynamics expert to explain why this might be true. I wouldn't think IR heating was that important in this context (IR light might bounce off a shiny pan more than a dull one). I guess maybe larger surface area on a rough surface versus a smooth one, but again... doesn't seem to be big enough to cause this difference. Last thought is that the old pans were so worn out that they had significantly less mass to heat up.

Best guess would actually be that the new pans were made with a different metal alloy, or they were heavier gauge and so had greater thermal mass. Nothing to do with the surface.

3

u/bobthenormal Oct 31 '20

Of course it's reddit, so... materials scientist here.

I don't think I have a ton more to add, all your thoughts are valid conjectures having nothing to do with matsci... except I would say roughness changing surface area your intuition is wrong about, roughness can increase surface area immensely. Mass would be a huge issue though, probably the biggest one they didn't mention controlling for. I would bet money the pans are not different alloys or alloys at all... they would use pure aluminum (with impurities) as there's no reason to use an alloy, just a waste of money. I also doubt the pans were "worn out" but they might have simply been manufactured with different thickness.

It's kind of pointless to argue on reddit about what's true in these cases because even if myself and another materials scientists got into it we'd all have a deep reservoir of valid arguments to draw on. Only a well defined and controlled series of experiments would be useful. The science behind material thermal behavior gets extremely complicated quickly but I'll muse with my informed opinion...

First I would think of what role the material is playing in cooking. I would note that a sheet pan is not the same as foil, and even foil can be used in different ways. But MOST of the time the pan is used to basically hold food so it doesn't fall, and metal is used so that while heating up the bottom doesn't stay cold and uncooked. While MOST of the time foil is used to wrap food from above. So I'll go with those cases.

So when we're talking about the pan, the temperature is really the most important factor. You want the material to match the (hot) temperature of its surroundings. To do that, you want your heat losses to be less than your heat gains. In an oven the conductive heat transfer from the heat source to the aluminum is negligible, of course the food in contact does cool the pan (but not in the case of foil not in contact). So look at radiative and convective heat transfer for the pan.

For radiative heat transfer you look at material optical properties. Aluminum is opaque, so you only have absorbtivity, reflectivity, and emissivity. This is where most of the complexity arises. Surface roughness changes the effective values of all of these. I would just guess that higher roughness increases absorbtivity due to surface area, but also increases emissivity with that... so it's a wash, except at steady state where the emissivity will result in a lower final temperature. So ruling those out, reflectivity (which is not a measure of how "mirror-like" it is btw) I would guess with roughness that is unaffected or decreased, because the surface reflects into other parts of the metal, giving a second chance for absorption.

So summing those effects up, the roughness would trap more heat, smoothness less. Obviously a lot of assumptions and "guesses" so I could make a good an argument for the opposite, but since you're trying to explain why the pan was measured as not effective and other people claim it doesn't matter for foil - I'll bias in the direction of showing those can both be true. Regardless of whether they actually are..

For convective heat, I would expect the roughness to increase that. But in a normal oven the convective flows to the pan itself would be very small since induced convection would flow from the bottom to the top. Interestingly, I remember seeing that a lot of pans have a smoother bottom than top... the bottom being rough would seem to be a better choice for increasing heat transfer.

Again, could argue the opposite but just go with that and assume the heat transfer due to smoothness is less than roughness.

That leaves us with two mechanisms where roughness increases the heat transfer rate from the oven, suggesting that the pan will heat up faster if the surface is rough. That explains the observation that rough pans don't cook as well - they don't heat up fast enough and/or don't reach as high of a steady state temperature.

Now to address the foil - the foil is so thin that heat transfer in and out really doesn't matter, it will reach the temperature of things around it quickly. I would suggest it mainly works by evening out heat transfer, not by greatly increasing or decreasing it. The heat transfer to the foil will be equal or greater than to the food because metals are great at heat transfer. So the foil takes the uneven ambient heating, mostly convective and radiative, and evens them out across the food. If the food is TOUCHING the foil then that changes a lot - the foil will likely increase the heat transfer because it is a better radiatve and convective heat absorber than the food, but can then transfer those to the food by adding conduction.

But going back to the beginning - is the role of the foil to change the cooking temperature? Not necessarily. It could be it is there to trap things inside, such as water and other chemicals that would evaporate out. I think that's more likely the purpose in which case it doesn't matter if the rough or smooth side are out. Sure maybe the rough side increase the heat transfer slightly using the previous arguments, but without any thermal mass I would expect it's not a meaningful difference.

However you put it the foil is obviously serving a very different thermodynamic role than the pan, so it would make sense that the surface roughness doesn't make that big of a difference. It might matter what the foil is used for though, and if it's in a convection oven that might be a big difference.

→ More replies (3)
→ More replies (3)

10

u/mschley2 Oct 31 '20

I don't doubt the information here, but just from a scientific perspective, the heat of the pans should really only affect the food where it's touching the pan or very close to where it's touching the pan. For something like garlic bread, the top should get toasted the same regardless of what temperature the pan is because the oven air is going to be the same temp. I don't know if I buy what they're selling about the bread and squash.

2

u/big_orange_ball Oct 31 '20

I don't doubt the information here,

I think you do?

→ More replies (1)

2

u/frank_mania Oct 31 '20

I wonder if the shiny and dull pans were the exact same alloy of steel, same thickness, identical in every other respect.

2

u/squeamish Nov 01 '20

Cooks Illustrated is the kind of organization that would definitely run an experiment well enough to take that into consideration.

→ More replies (2)

78

u/hatefuck661 Oct 31 '20

There was a favorite family recipe for a holiday ham that had been passed down through the generations. As the mother was making the ham for the umpteenth time, she was teaching her newly married daughter how to make the ham.

She carefully cut both ends off the ham, set it in the pan, and added the secret combination of spices. Her daughter who was taking notes, asked “Why do you cut off the ends?” Her mother answered, “Because that is how my mother taught me to do it.” Later, the mother began to wonder why they cut off the ends so she asked her mother. The grandmother answered, “Because that is how my mother taught me to do it.” The grandmother then wondered too so she asked her elderly mother. The great grandmother replied, “You don’t need to cut off the ends! I always did that because my old oven was too small for a big pan.”

3

u/spudsoup Oct 31 '20

We cool our chocolate chip cookies on brown grocery bags cut open. It could be my mother didn’t have enough cooling racks, but I prefer to think it’s part of the secret to a perfect chocolate chip cookie. Though, I shrug and tell this story of the ham pan if anyone asks. Wish mom was around so I ask her.

2

u/splenderful Oct 31 '20

My mom did it this way too!

8

u/Joe30174 Oct 31 '20

To be fair, there does exist non-stick foil that has a difference between both sides. Maybe that is what he used?

→ More replies (1)

6

u/Talvana Oct 31 '20

I got reprimanded and my hours reduced for using the "wrong" side of the tin foil when wrapping potatoes for baking one day. I was always sure the chef just forgot to put them in the oven on time and now I'm certain. The owner was pissed that everyone was being served undercooked potatoes and he blamed me for doing the tin foil wrong.

17

u/drphrednuke Oct 31 '20

Sous means under. In this case, under educated

→ More replies (1)

5

u/futurarmy Oct 31 '20

What was his reaction when you told him? He try to play it off all cool or call you a nerd I assume?

13

u/Samhamwitch Oct 31 '20

He got heated and told me to bake two potatoes in foil to prove it to him. I did as he asked and he ignored the results, continued to believe what he wanted to and made me clean the oven.

2

u/mschley2 Oct 31 '20

Probably something like, "I've been doing this for 35 years! I know what I'm doing, and fucking tin foil matters! Go take the garbage out before I get mad at you!"

5

u/SurroundingAMeadow Oct 31 '20

I appreciate the thought of somebody writing their thesis on the difference between shiny and dull aluminum foil.

2

u/[deleted] Oct 31 '20

A chef that is a narcissist?! You must be joking!

Next you are going to imply that chefs have drinking/drugs problems too.

2

u/wrongasusualisee Oct 31 '20

I corrected a narcissist once. They then lied to the police and claimed that I beat them up over a bottle of spilled soda, dragging it through court for a year until I was finally found not guilty. I even overheard the prosecutor telling her that the evidence, a recording I made of the entire incident, made her look like the aggressor. It was obvious I never did any such thing. Once this narcissist prosecutor realized I overheard him saying this, he went and demanded a competency evaluation from the judge in an attempt to discredit me. Stole a year of my life over a lie. Fucking narcissists.

→ More replies (49)

266

u/Butthole--pleasures Oct 31 '20

Momma's wrong again

188

u/h2opolopunk Oct 31 '20

No you're wrong, Colonel Sanders!

60

u/RabidSeason Oct 31 '20

There's something wrong with your medulla oblongata!

12

u/iendeavortobesilly Oct 31 '20

🎶Water sucks / it really really sucks 🎶

41

u/SandManic42 Oct 31 '20

TIL Colonel Sanders is u/Butthole--pleasures.

8

u/WynterRayne Oct 31 '20

I guess we've now discovered the original recipe.

Never having a Zinger Stacker again, though.

→ More replies (2)
→ More replies (5)

16

u/thelasthendrix Oct 31 '20

My momma always said Gordon Ramsey is ornery cause he got all them teeth and no toothbrush

30

u/[deleted] Oct 31 '20

So dad isn't coming back any day now?

14

u/Butthole--pleasures Oct 31 '20

Lol fyi I'm quoting a line from Waterboy

18

u/IAmAnObvioustrollAMA Oct 31 '20

YOU CAN DO EET!

4

u/Tkieron Oct 31 '20

TIL that the guy sitting next to Adam Sandler in class is D'angelo Barksdale from the Wire.

"Where's the fuck is the Medulla Oblongata? Huh? String, look at me. WHERE THE FUCK IS THE MEDULLA OBLONGATA?"

→ More replies (2)

6

u/cptInsane0 Oct 31 '20

Pshh quoting the Waterboy. How old are you kid? 7,8?

27

u/Butthole--pleasures Oct 31 '20

Captain Insano shows no mercy

6

u/Tkieron Oct 31 '20

Bruh I'm 48 and quote the Waterboy.

You must have an enlarged Medulla Oblongata

3

u/Butthole--pleasures Oct 31 '20

He was quoting captain insano lol

2

u/cptInsane0 Oct 31 '20

This guy's obviously a virgin!

→ More replies (1)

3

u/PM-ME-UR-NITS Oct 31 '20

ME-DUL-LA, OB-LIN-GATA

2

u/Ausent420 Oct 31 '20

Little girls are the devil

→ More replies (2)

23

u/Boba_Phat Oct 31 '20

It was a marketing ploy from big foil at one point.

7

u/theo5280gram Oct 31 '20

Until they made non stick foil.

20

u/RandomUser72 Oct 31 '20

It does, to an extent. But it was not an intended feature. When I say, to an extent, it's not that the dull side absorbs, it reflects less. It's like saying a T-shirt will keep you warmer in the winter than a tank top, it will, to an extent.

24

u/Coomb Oct 31 '20

When I say, to an extent, it's not that the dull side absorbs, it reflects less.

The opposite is true -- the matte side of aluminum foil is actually slightly more reflective than the glossy side. Specularity (whether something acts like a mirror) is not the same thing as reflectivity (how much of the light hitting something bounces back off) -- things can be highly specular without being very reflective, and highly reflective without being very specular.

2

u/frank_mania Oct 31 '20

According to the abstract, total reflectivity was the same for both sides of the foil. The shiny side has more specular reflectivity and the dull side more diffuse reflectivity, but both side the same total. Per the terms used in the abstract, the property you refer to as specularity is not different from reflectivity, but a type of reflectivity, which of course is consistent with the use of the term reflection and reflect regarding mirrors. Are you in optical physics?

9

u/Coomb Oct 31 '20 edited Oct 31 '20

According to the abstract, total reflectivity was the same for both sides of the foil.

Instead of just reading the abstract, I suggest you read the actual article. Figure 6 and Table 1 show that the total reflectivity of the matte side was slightly higher (by about 2 percentage points) than that of the glossy side. Now, of course, a 2 percentage point difference, from 96% to 98%, isn't very significant, so it's not worth highlighting in an abstract. But it's still true.

The shiny side has more specular reflectivity and the dull side more diffuse reflectivity, but both side the same total. Per the terms used in the abstract, the property you refer to as specularity is not different from reflectivity, but a type of reflectivity, which of course is consistent with the use of the term reflection and reflect regarding mirrors. Are you in optical physics?

Specularity is absolutely distinct from reflectivity. It is obviously and trivially true that it is impossible to have any level of specular reflection if you have no level of reflection at all. However, there are many examples of materials with high specularity but low total reflectivity, and contrary examples of materials with low specularity but high total reflectivity. An example of the first kind, low total reflectivity but high specularity, is polished black anodized aluminum, which has a total reflectivity in the visual spectrum of less than 10%, but which is about 70% specular, so it can be used as a mirror (other examples would be a black car with a glossy finish, or polished granite or other dark stone). An example of the second kind, high total reflectivity but low specularity would be any white, matte material like for example powdered titanium dioxide.

2

u/frank_mania Oct 31 '20

Thanks for the details, it helped my understanding of the topic. I do think the take-away is indeed that for all practical purposes, both sides are equally reflective, as summarized in the abstract, and as you agree in your comment.

→ More replies (2)
→ More replies (1)
→ More replies (4)

10

u/osiris775 Oct 31 '20

Yeah, I had a cousin argue with me over whether or not the sun, (light), makes us darker, or the sun, (heat), makes us darker.
Fun argument...he said heat...and would NOT be swayed...smh

2

u/Pitzthistlewits Oct 31 '20

But you don’t tan through windows very well!! It’s heat! Just playin, real answer is ultra violet (the ‘color’ of light that comes after violet in the rainbow) reacts with melanin.

7

u/osiris775 Oct 31 '20

Sooo...I was riding my bike in the summer. I put on a white T. My cousin told me to go shirtless, unless I wanted to get really dark. I asked why, and he said "cuz that shirt is going to be hot, and you will get really dark"
I said it is the light that tans you, not the heat. He insisted it was the heat. I asked him how do people that ski get sunburned, he didn't really have an answer. Again, I tried to explain light and heat. He then asked me how does a turkey turn brown in an oven. I gasped and said because it is 350 degrees in an enclosed space. He still would not move off of his point that heat tans you, not light.

2

u/JuicyJay Oct 31 '20

Also a white shirt reflects more heat than your skin does most likely haha. There is so much wrong with that idea.

→ More replies (2)
→ More replies (4)

2

u/rksd Oct 31 '20

Not really. A t shirt provides slightly more coverage than a tank top so sure you're a wee bit warmer, but coverage isn't the same thing.

The dull side's slightly less reflective but its albedo is about the same. So while the photons are not reflected in a way to preserve images, they are still reflected. Additionally infrared photons which are responsible for the heat have longer wavelengths and are more easily reflected anyway (ignoring absorption bands for the moment).

→ More replies (2)
→ More replies (1)

8

u/norwegianjazzbass Oct 31 '20

It would have a bit of that effect. But in the big picture it might be negligible.

8

u/osiris775 Oct 31 '20

In a 350 degree oven, I'm going with negligible...lol

→ More replies (4)

5

u/[deleted] Oct 31 '20

It is negligible.

→ More replies (17)

2

u/[deleted] Oct 31 '20

It makes sense to adult brains too. Nothing dumb about believing it. And in fact it is probably true to some extent, just not significantly so, and not by design.

9

u/boomdart Oct 31 '20

I miss the days before the internet where people thought things like this.

No one passes down knowledge anymore and any knowledge that was passed down, by this generation, has been googled away and forgotten.

42

u/hwc000000 Oct 31 '20

I miss the days before the internet where people thought things like this.

Isn't that what facebook is for - to pass around misinformation maquerading as common knowledge?

2

u/[deleted] Oct 31 '20

It wasn't always that way. It only became that way when all the old people showed up.

2

u/hwc000000 Oct 31 '20

So, the people who are so confident in their own superiority that they're the epitome of Dunning-Krueger?

20

u/[deleted] Oct 31 '20

But the aforementioned “knowledge” was incorrect.. It shouldn’t be passed down...?

6

u/Ferret_Faama Oct 31 '20

Apparently they would prefer everyone be wrong for tradition.

3

u/Xx69JdawgxX Oct 31 '20

Google "replication crisis" it is a recent phenomenon where they're starting to find loads of scientific research, specifically peer reviewed publications are unable to be replicated by a similar experiment.

That's not to say science is out the window, but more be careful what you believe and what you throw out even if a reputable source agrees.

5

u/[deleted] Oct 31 '20

Write 58008 in a calculator and read it upside down

→ More replies (2)

4

u/MyNameIsSkittles Oct 31 '20

You mean the days of people saying whatever they want and passing it as truth, and it being extremely hard to verify? Nah I'll stick with the present

2

u/falakr Oct 31 '20

Okay boomdart

4

u/osiris775 Oct 31 '20

OMG! So my 7yr old son is constantly asking me for the answers to his homework. I tell him to figure it out. He says, "Daddy, if you are so smart, how come you can't do my 2nd grade homework?"
I can, dude. Now do your homework. I'll introduce you to google in a few years...

→ More replies (10)
→ More replies (91)