Mutarotation: a sugar that spontaneously changes from sweet to bitter
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- เผยแพร่เมื่อ 7 ก.พ. 2025
- Simple sugars can exist in multiple molecular conformations, some of which have different tastes and optical properties.
Steve Mould's video on optical rotation: • Why Sugar Always Twist...
Reaction's video on Mexican Coke: • Everyone is Wrong Abou...
Research paper describing enzymatic synthesis of L-glucose: nopr.niscpr.re...
D-mannose on Amazon: www.amazon.com...
My crystals were almost entirely the sweet form, but it is possible that your bag may have the bitter-tasting form to begin with.
D-fructose on Amazon: www.amazon.com...
D-glucose, also known as dextrose, also known as "corn sugar", can be found on Amazon, or beer homebrewing stores.
/ appliedscience
Legitimately one of the best channels on TH-cam
Yeah!!!
100%
passion channels are always better than "for entertainment" ones
Yeah, and we get about two videos a year.
Ikr. Few channels can post quarterly and still be relevant.
Relevant to what I do as a Job? No.
Relevant to one of my hobbies? No.
Still sat through every minute of this vid, because you can make anything interesting. Stay curious!
Ha, it is relevant to making chocolate or fudge and an assortment of candies.
Those shots downward of the reflected light rotating in different ways is by far one of the clearest examples of polarization of light. Its something that should be in chemistry textbooks even, its so succinct
I remember something that looked vaguely similar to that in my organic chemistry textbook, though it was definitely not a photograph, it was a drawing, but it looked somewhat similar. I also remember identifying chemicals using various basic instruments such as a meltemp, a polarimeter, and simple paper chromatography, and probably a few other things before we got on to using FTIR, NMR, MS, GC, LC, MS/MS, LC-MS/MS, GC-MS/MS, and probably a couple I can't remember.
It was an old textbook at the time as the professor was quite old and she said once she found a good textbook, she kept using that, same edition even, as long as she could (like she'd stop and look for a new one if it was hard to obtain or started to get expensive or whatever), she allowed us to use different editions if we could get them cheaper, and if the problem sets were different or something we could email her for a PDF but other than that it was up to us to figure out which page correlated to what.
I remember one professor for one of my classes that just said "you wont need a textbook" in an email, then first day he had a student come to the board to write down letters he spoke, which eventually wrote a link on the board to a download for the PDF of the textbook he wanted us to use. One of my favorite professors of all time, dude didn't want people paying (wasting) money to support the publisher, but he was also smart about it, he left zero papertrail of what he did, so if a student was a snitch, they'd have no proof. Even if they took a picture of the link on the board, it wasn't his handwriting!
@chemputer man, you had some amazing teachers it sounds like. I'm jealous a bit haha. I had some amazing professors at Sac State in the physics department, but none to the point if actively engaging in textbook piracy
This channel really is a treasure trove. How many people are able to speak so comfortably of such a variety of subjects, making them accessible and interesting, and so often putting together incredibly advanced practical demonstrations...
It's really spooky to realize that equilibrium often means changing constantly. Reality is extremely messy when you really look closely at it.
What do you mean? What is constantly changing?
@@leocurious9919 6:28 ff.
@@leocurious9919A turns into B at the same rate as B turns into A is a simple example. Constantly changing, but proportions remain the same.
When you look at a whole lot of individual pieces, it inevitably turns into probability and statistics.
@@pseudolullus Ah, on the microscopic scale, sure. Like temperature it is very different micro vs. macro.
1:35 This effect is actually something that happens when you drink tea. Most teas contain monosaccharides glucose and fructose in different amounts depending on the varietal and type of processing. Most teas are substantially sweeter when cooled down, and is especially perceptible with teas that usually are not that sweet when warm (for example, rock oolong teas).
I always wondered why this was, and though it was perhaps due to the tastebuds having a different response at different temperatures. I never figured it would be a change in the molecules!
Another tea observation, when I had tea at a friends house it was always a nice clear orange. For a long time I wondered what the secret to this was as my tea was always blackish. It turns out if you use soft water, distilled water, or add a little acid you can have a more clear orange tea. Seems I have hard water and it appears to react with the tea in some way, tannins?
@@katgod Adding something acidic to hard water would check out then. Hard water is slightly alkaline from the calcium and soft water has much of the minerals removed so it is slightly acidic.
Happy New Year, Ben!
We did a lot of work developing an enzymatic process for D-psicose, an epimer of D-fructose. It's about as sweet as table sugar but only 1/10th the calories. It's made from HFCS so you get an equilibrium between glucose, fructose and psicose. I think they use simulated moving bed chromatography to separate everything, but not sure.
Sugar chemistry and artificial sweeteners are pretty interesting. I always found it interesting that 2 amino acids linked together (aspartate and phenylalanine) with a methyl ester group and you get something 200 times sweeter than table sugar with no calories (aspartame, aka nutrasweet). Or sucralose, replace a few OH on sucrose with Cl and you get something 600 times sweeter. The history behind it is pretty interesting too, if true, when a scientist was told to test it and he thought he said taste it.
Oy vey play with polymers and see what happens..😅
I’ve been using Allulose (D-psicose) for a few years. Thank you for all your work! It’s made a great small business for me.
Once Trump gets RFK jr into place, HFCS will be banned! 😉
Love the _"Hands of Fate"_ reference. Torgo music is now stuck in my head.
I like to see “MST3K forever stream” the Torgo theme is now also in my head.
D-Manos: d-hands of fate
t-t-the master wouldn't like it.
@@macmacox He sleeps in a bed of his own drippings.
Thank you for making a video, I’ve really missed your channel
One of the substances you made is called "invert sugar" or "inverted sugar syrup" and it is popular additive in food and medicines as it allows using less sucrose while attaining same level of sweetness. IIRC the solution is sometimes called "syrup simplex" (i.e. "simple syrup") in pharmacopoeias. The surcose is basically pre-digested for you by acid-catalysed hydrolysis.
I was once surprised finding out that sugar can be used as a reducing agent as the aldehyde group easily oxidizes into a carboxylic acid group. It can also undergo disproportionation (dismutation) into a 50:50 mixture of corresponding alcohol and carboxylate by the action of a strong base, also known as Cannizzaro reaction.
I great amount of work focused on the wet chemical analysis of carbohydrates has been made in late 1940s and 1950s and this was before instrumental analysis became so ubiquitous. I can recommend a book "Periodic Acid and Iodic Acid and their Salts" (Frederick G. Smith, 1950) that discusses how hypervalent iodine compounds can be used for identification and determination of various carbohydrates. These specialty reagents, particularly periodic acid and periodates, are being used in modern chemical processes, e.g. for the preparation of niche materials such as dialdehyde cellulose.
This is so interesting! I always wondered what inverted sugar actually was.
I searched about it but couldn't understand what it was.
Thanks so much for this! I'm a biochemist and teach mutarotation, but I had no idea that the flavors of the sugars changed! I'm demoing this when I teach it in the spring!
Fundamental chemistry at it's finest - hell yeah!
Thank you for the finest and highest quality content on youtube!
Ben, this is fantastic.
Thanks for closing out the year with a sweet video!
Always love learning about something I've never heard about before! Happy new year!
I've been itching for a new Applied Science video for what feels like ages!
Sugars tend to be a bit of a nightmare for chemistry students. These properties were discovered by Emil Fischer with not much more advanced capabilities than a high school chemistry lab, so he basically gave his best guess on how they actually worked and those guesses stuck as definitions. Now, a bunch of things relating to sugars are a bit backwards compared to our modern systematic nomenclature which can become rather confusing.
Franklin guessed at the polarity of the electron and we've been living with that decision ever since!
The thing with L and D, and with + and -, is that with just the formula, you can know if a sugar is L or D, but you can't know if its + or -, without experimental data (or simulation i guess)
That's probably why the notation never dissapeared. L/D is useful, even if L/D may not have been the most descriptive letters for it.
On the other hand, +/- is kind of a weird notation.
Imagine we added the color of a compound in its sistematic name. That would be odd.
@@ficolas2sometimes they do; azulenes come to mind ;)
@@T3sl4 patiently waiting for metric electricity polarity
Fischer Esterification is how you make biodiesel from waste oil.
I was taught that L-glucose would make a good no-calorie sweetener when I was studying at the university. Well, somebody figured out how to do that cheaply (about 10 years ago). It turned out that L-glucose is also a very good laxative, so much that it might be useful for things like colonoscopy prep.
I'd be very interested to know the cheap method of production. Sigma sells l-glucose for $100/gram. It's true that the hygroscopic properties that would make it a great baking ingredient, also make it a laxative. Probably the best way to use it commercially is to blend it with normal sugar, and reduce the calorie content by just 20%. Although, I agree that artificial sweeteners like sucralose are difficult to beat for beverages and similar things.
Reminds me of Olestra.
Is that the stuff that made those sugar free gummy bears infamous?
Hmm, that seems consistent with what I have been fed prior getting anal probed. Fortunately by doctors, not by aliens.
Edit: nope, it wasn't sugar based. Some kind of glycols were in it.
I was wondering if bacteria or anything can ferment the stuff, and well, I guess that answers my question: if they did, you'd have terrific gas from the ensuing carnage, as this is what lactose intolerance is.
...Would that then mean, if such a product became widespread, it might not degrade quickly in the environment? Abiotic paths would still degrade it pretty quickly, say days to months (so-called reducing sugars, like glucose, are easily oxidized by fairly mild ions like Cu(2+), for example), but in the mean time, might it stick around? I wonder if its use would require some rethinking of wastewater treatment? Perhaps there are bacteria or fungi that can consume it, that just don't happen to be present in the human microbiome.
...Huh, this comment was just idle curiosity out loud, and I expected to be quickly informed by internet search... but alas, only one partial hit? Wikipedia mentions Burkholderia caryophylli having some ability to oxidize it, but I don't see any promising hits for articles about it. Perhaps L-glucose's interaction with known biological systems is very poorly researched!
I'm always excited when you do an upload. I know it's going to be something really interesting.
It's also nice that you don't upload too many short videos at too frequent of a rate.
You save up a good topic, and do lots of work for every single video.
This makes them more of a special treat they do arrive. Please keep up the great work!
This was a big section in my first Orgo Chem at college and I loved it. And yeah, the D and L refer to the direction of the functional groups with respect to right hand rule and prioritization of those chemical groups around a central atom (usually carbon), rather than optical rotation.
That's what I remembered...I think that it was just coincidence that his first examples where D and L also correlated with bending light to the right and left. However, just to make sure, I found one internet sight where that actually stated that it was the direction the that molecule rotated...which I am still skeptical about...
I believe you're referring to R/S notation, which is labelling priorities of the substituents attached to a chiral center. D/L is a quick and dirty legacy of relating molecular light polarization to the absolute stereochemistry of R/S glyceraldehyde (which could not be accurately determined when the D/L system was created), and the sign of optical rotation (+/- system) is an observational system based on the direction of light rotation which is not constant (it depends a lot on the parameters of the system).
Thing is--all these parameters are related to some extent, they just tell you slightly different things about the same system. D/L cannot tell you about specific stereochemistry of a molecule, but is specific (eg, we know the stereochemistry of a D-glucose molecule) to that enantiomer of the molecule. Same thing for +/-. R/S notation will tell you the exact stereochemistry of a molecule but will not tell you which way it will rotate optical light on its own(unless you already know, for example (2R,3S,4R,5R)2,3,4,5,6-pentahydroxyhexanal is D-Glucose, so you know which way it will rotate light).
Source: am chemist + clayden's organic chemistry textbook for reference.
I’m always blown away by how diverse and interesting all the topics you cover are
The only thing you can predict is that it will be cool
I never know fully what you're actually talking about and that doesn't stop me from loving the videos non the less.
the radial arms thing absolutely blew me away - so cool. I have no idea how or why you would do it, but seeing a gradient of mixtures along the tube where it bends one way then the other would look crazy.
Thanks for putting these videos together, you are truly one of the all time greats - I will always drop whatever I'm doing to checkout what you've been up to - never disappointed.
Thank you for always taking a deep concept and distilling it for the masses. Happy and successful new years!
It's already 2025 here - and what a great start for a year should it start with new Ben's video!
Happy New Year, mate!
When one of my cats got a preliminary cancer diagnosis I started looking into sugars, because of how cancer cell metabolism works, and it turns out a team of researchers wrote a paper about the cancer-treating properties of L-Sorbose
It can't do it alone, unfortunately, or they'd have announced they have a cure, but according to their research it significantly boosts the effectiveness of chemotherapy.
Sugars are wild!
(L-Sorbose is very common and used to synthesize vitamin c)
Welcome back we have missed you.
This has got my mind working again on how to make a non sweet cotton candy. As a Chef I have been experimenting and failing miserably for 15 years. Someday!
For some reason this got me thinking of the koji starter / mold which I’ve seen being very stringy. Maybe if you string it out enough you can get a cotton candy like structure
You've just invented cotton :P
Every time I see a new video from you I know I'm going to learn something interesting and this one definitely didn't disappoint! Chemistry isn't normally something I think much about but you found some very interesting tidbits to share.
Good to see you back. Most complex subject, but I will watch it. Keep 'em coming!
A strong theory as to why the DNA molecule has a prefered optical isomerisation is that cosmic rays striking the earth for billions of years also have a preferred rotation/polarisation.
Most DNA double helices are right-handed.
In biological organisms, amino acids appear almost exclusively as left-handed (L-amino acids) and sugars as right-handed (R-sugars)
I could see this potentially working if the solution where the first building blocks of life were generated within a solution that acted as a polarized light filter or a polarizer. It wouldn’t necessarily even require cosmic rays, since ultraviolet light from our sun is enough to break apart molecules.
Why do cosmic rays have a preferred rotation?
@thewhitefalcon8539 now that is a good question.
"The cosmic microwave background is polarized at the level of a few microkelvin. There are two types of polarization, called E-mode (or gradient-mode) and B-mode (or curl mode)."
I tend to think it's either a result of bias in how the big bang occurred or due to God. (Or both).
I love anyone investigating nature, this channel always inspires!
Happy New Year!! It's so wild clicking a random video about a cookie machine would bring me so much education and enjoyment for over a decade.
Great to see the NileRed gear make an appearance.
This simple method of observing inner-reflection of unidirectionally-polarized light in a tube, filled with sugar solution, is the brightest idea I learnt today.
I knew that the various kinds of sugars can have different isomorphic shapes and forms, but now I know that all this is at least 3 or 4 times as complex than I was previously aware of. Fascinating!
FINALLY, youtubes very best content creator made another video- I will treasure this until evening and enjoy full blast science!!! Happy new year Ben and thanks for 1st grade premium entertainment as usual!!!
I wish we could make polarized headlights and windshields a thing. It would greatly reduce the glare of the ever intensive bright lights cars have now.
Are you sure this would work? I don't know much about polarization but if all cars had polarized headlights to the same "direction", then if you filtered that out, you wouldn't see your own (unless the reflection of objects changes the polarization which I don't know). Also, what about the light from street lights? Wouldn't those drop to around 50% brightness for drivers?
Wearing polarized sunglasses would help except that it would also decrease the light from your headlights, this includes clear polarized sunglasses assuming you could find them. I am not sure this is what you really want but I do sympathize with the desire, I also suspect that it maybe more of an older person problem than a young person problem but I am not 100% sure.
@@mik13ST That's a good point. I never thought about the driver's headlights... My guess is that the reflected light would not be polarized. Street lights won't have a filter on them, so they would be mostly normal.
@@katgod I do have polarized sunglasses, and they help a lot. It's not just an old person problem. Headlights never used to be as bright as they are now. They are considerably brighter than they were 20, even 10 years ago. I used to drive at night all the time. No it feels like everyone has their high beams on all the time.
Always a treat when we get a new video!
There will never be enough of this sort of content on TH-cam
Ben is the very best kind of teacher.
Oh, how I have missed you... your videos bring me so much joy!
Happy new year.
had to do a double take at my notifications, happy new years ben!
As someone who actually works with HPLC and Sugar analysis I can not wait to see your next video!
Oh my goodness! I think of you often. I'm glad you're doing well, and I hope all of your Christmas dreams came true! Happy New Year!
Those equilibria you mention bring a good deal of complexity to the soft drink manufacturing process, as they must be taken into account during syrup preparation. Great topic: sugars have _a lot_ of interesting quirks.
thankfully, there was more to this video than I thought there would be from the title.
Happy new year, always worth the wait to see one of Ben's videos
This is one of the most fascinating things to start the year by learning.
Weird how it could relate to planetary formation.
Happy new year Ben and thank you for everything you do for us!
Spectacular and timely. Mould *and* Grant Sanderson (and amazing visualizations of EM waves in matter).
Sugar chemistry is maybe the most famous "fundamental" chemistry research areas that amazes us non professionals. 75 years ago and all those clever experiments needed to figure all this out! You are indeed creative and attentively observing in a way that reminds us about them!
(Von Euler Chelpin is one famous name I recall)
Been a while since you last uploaded, glad that you're back.
Not a chemist but have an undergrad in chemistry. Very excited for upcoming videos after hearing you've been into chemistry recently!!
Ben, you never cease to amaze us. Amazing work, thank you for making us smarter.
Hapoy new year!
I believe that the spirals are a conoscopic interference pattern. It may be something to look into and see if it fits what you are seeing. I think the polarization of the specimen and the meniscus of the water refracting the polarized light are making it. Interference patterns are commonly used for identifying minerals with petrographic microscopes.
About time 😂 been checking every few weeks for a new upload, glad you’re doing good!!!
A very happy new year to you, Ben. You are the best!
Yes! what a good way to bring the new year in with a new Applied Science video!
Thank you ! Your videos are a great new year gift.
I watched the video by Veritasium, but you way of pointing the lens down the length of the tube makes the effect so much more directly apparent. Even though with the reflection and stuff the actual math is more complicated, the visual effect is on point for the effect you want to show.
What an awesome video! Thanks for sharing the simplicity beyond complexity! cheers! 🌱
The best science themed-youtube channel.
I’ve experienced the fructose one in South Korea. My apartment was being bombarded by focused microwave radiation. One of the early indications was new bottles of sealed low moisture solutions like molasses and pesto spontaneously bubbling out of their container when placed on a particular shelf. A large metal mixing bowl with a ridged concave base created an area of scorched, brown plastic right at the focal point when left on the same shelf. In a similar manner all high fructose based beverages I brought to the apartment went from flavorful to disgusting between bringing them home in the evening and waking the next morning. It was great driver to learn more about the physics, chemistry and technology that was behind it. I’m very thankful to Ben’s _Applied Science_ , _NighthawkInLight_ , _CuriousMarc_ and _Tech Ingredients_ among others for communicating so clearly about the science.
Just when you wonder if he kicked the bucket. That evening is saved. Thank you for his blessing !!!!❤
Very cool video. Was a little disappointing when I saw it was about sugar and not electroplating or x rays or something but this complexity in something so otherwise mundane is just fascinating. Happy nye Ben! Excited to see more of your videos in 2025 making me appreciate the amazing world we live in
I would LOVE more content on DIY Low/No-Caloric Sweeteners and stuff!
It’s in my Bio-Petrochemistry niche…but you can taste it!
Does that mean that some (many?) no-calories sweeteners are actually a different chirality and simply rely on our body not being able to metabolize it?
Thats one of the best starts for a new year, thank you ben and i am so happy you are fine after the long silence, happy new year❤
Manos the Hands of Fate is a deep cut, well played
Very neat to see this - I see these phenomena all time when doing optical petrography, where polarized optical methods can help identify minerals in a thin slice of rock under a microscope. Ben probably figured this out already, but here's a more detailed explanation for those spiraling polarized reflections:
The reason the polarization rotates in the first place is because the solution actually splits the incoming light into two rays with perpendicular polarizations, one of which has a higher refractive index and thus travels slower through the solution. This means the phase of the two rays change with respect to each other as they traverse the solution, so the sum of both rays has a net polarization that rotates gradually up the solution. The different refractive index of each polarization is called "birefringence" and is actually what's responsible for the colors in crossed polars. Certain solutions make one of the rays go faster or slower, resulting in negative or positive birefringence, and thus clockwise or anticlockwise rotation.
Because the net polarization lines up with the angle of the upper polarizing filter every 90 degrees, it goes dark ("optical extinction") every 90 degrees, creating a pattern with four dark lines called an "interference figure." This is the reason there are four dark lines in the reflections.
As for the coolest part, the spiraling: because the cumulative amount of polarization rotation increases steadily as light traverses through the solution (up the tube), the angles at which the four extinctions reflect correctly off the glass rotate too. So Ben literally documented the progressive rotation of light through the solution! Wildly cool to see that.
For anyone nerdy enough to care more, just Google image search "optical petrography" or any of the terms above. They might not clarify why all this happens, but they sure do make for some pretty pictures.
So much get to be discovered in chemistry. I find it one of the most exciting fields in STEM
That's a really cool observation, I never heard about mutarotation before. Btw glucose article on wikipedia states: "These five structures exist in equilibrium and interconvert, and the interconversion is much more rapid with acid catalysis." So little bit of acid should establish equilibrium between various forms quicker.
At highschool we did meassurments how quickly sucrose hydrolyse to glucose and fructose in acidic environment. We meassured angle of rotation with polarimeter in some time intervals until it became stable and from those data calculated speed constant of the reaction. All polysacharides hydrolyze in acidic environment, even starch and glucose (but the conversion is pretty slow even when heated). But if I remember correctly, we did some experiment in high school like this, I think with starch. Heating in acid solution, and test it with Fehling solution for glucose in certain time intervals.
Sweet way to start the new year ! have a good one Ben !
What a treat, ending the year with a new Applied Science video. Happy New Year Ben!
What a pleasant start of the year!
I remember that topic being just another excercise to do in the lab, really sad that we didn't get to try the taste analysis. Would have certainly made me more excited for the topic.
Nice! Always excited to see a new upload from you!
Long time no see ! Its ok , your an original TH-cam legend!
Always love an upload from you bro!
Ben stay making the best content on TH-cam
Fascinating learning that starch and cellulose are the same thing... Thanks for that!
Another absolute banger, Ben. Happy new year!
Fascinating. I apparently lack the gene to be able to taste bitterness, but my wife does have it and can taste it strongly. Should be interesting to see if we can both reproduce this result... Will report back in a few weeks when we can get some materials!
>Should be interesting to see if we can both reproduce this result... Will report back in a few weeks when we can get some materials!
I thought it takes at least 9 months plus a few extra years
I'm really excited for the next few videos!
This reminds me of how honey and agave nectar taste bad when you mix them with water even when fully dissolved in, but if the water is hot while mixing then it actually tastes right
I have been studying chirality in ochem, so this is a nicely timed video. Awesome material!
as a glycobiologist and Applied Science fan, I'm stoked about this crossover!
I just got my first set of organic chemistry gear. Your channel really helped inspire me. Thanks!!
My goal is at home tomography and chromatography.
But I'm going to start with recycling Styrofoam Polystyrene. Baby steps.
Happy New Year!
As a chemist, I suppose I am used to it. This video definitely reminded me what it was like to be unfamiliar with all this, though. Good job.
Best dude ever, happy new year Ben!
Drinking from laboratory glassware is the first thing they teach students not to do. When I did my internship the group there had made beer and the group leader took a beaker and filled it with said beer for me to have a taste. The 'cognitive' dissonance I experienced was real. Of course, the glassware is super clean as it gets cleaned by a custodian department which has big dishwashers. The glassware needs to be super clean or else experiments might get contaminated.
I have specific kitchen glassware. I wouldn't ever admit to having a kitchen hotplate stirrer for gravies and other such delicate culinary endeavors because that would be crazy. Melting butter for popcorn directly on a burner in a tiny beaker makes friends laugh.
I missed the videos. Your work is amazing ❤
Organic chem and bio students should watch this -- very lucid.
your posts are wonderful and a wonder .
thanks for your time
I'm always excited to see a new video from you! This one is very cool! Happy New Year!
I just finished a chembio class that have a large emphasis on organic carb chemistry and this video really made my suffering worth it lmao
Yes, chemistry is complex. Right now i understand why my sweetener (stevia, actually) tests very differently in just the same cup of tea! Thank you!!!
this guy might be the smartest person on the internet
Sweet! Happy New Year to Ben and all.
This is the way to start a new year, with an Applied Science upload! 🥳🎉
Great to see you post a video, thanks and happy new year
When I imagine these simple molecules thermodynamically re-assembling into different forms constantly en-masse but preferentially one way or another depending on the environment I'm starting to understand how someone could come up with the concept of Thermodynamic Computing and how truly powerful such a computer might end up being.