With New Year's Eve upcoming, a large number of people will celebrate by popping open a bottle of champagne.

The bubbles in your glass may seem simple enough, but there's actually a wealth of interesting chemistry behind them – chemistry that's vital for the perceived taste and aroma of the wine. There's a lot more to the bubbles than you might think, and this post picks apart some of the chemical compounds involved.

The obvious chemical contributor that causes the bubbles to appear in champagne in the first place is carbon dioxide, which originates from the fermentation process.

Champagne is unusual amongst wines, in that it undergoes two fermentations – one before bottling, and one in the bottle before it is drunk. The second fermentation produces the carbon dioxide and ethanol that are vital for the finished product.

An average 0.75 litre bottle of champagne contains around 7.5 grams of dissolved carbon dioxide – this may not sound like a lot, but when the bottle is opened, it would release around 5 litres of carbon dioxide gas if you allowed it to bubble until flat. In an individual champagne flute, assuming a volume of around 0.1 litres, this would equate to approximately 20 million bubbles. This isn't even the bulk of the carbon dioxide – only around 20% of it escapes from the wine in the form of bubbles, with the other 80% escaping via direct diffusion.

The bubbles themselves need nucleation sites to form in the first place. Tiny cellulose fibres, which are either deposited from the air or left over from when glasses have been wiped with towels, allow the trapping of gas molecules as the glass is filled.

The dissolved carbon dioxide wouldn't usually have the energy required to push through the intermolecular interactions of the liquid molecules, but the pockets of gas lower the energy required, thus allowing bubbles to form. They can also form if the glass has had a specially etched portion during manufacture.

As well as giving champagne its characteristic fizz, studies have shown that the bubbles are also vital contributors to the flavour and aroma of the wine. They can pull some compounds in the wine with them as they rise; when they reach the surface and burst, these compounds can be thrown into the air within tiny liquid droplets.

Scientists have analysed the composition of these droplets, collected by holding a microscope slide over a champagne glass then transferring them to a solution which was then run through a spectrometer to identify compounds present.

A large number of flavour and aroma compounds were discovered in the droplets, a selection of which are shown in the graphic. Hundreds of components were present, with some still yet to be identified, but interestingly, the composition of these droplets differs from that of the main body of the wine. This is due to the fact that only certain molecules are pulled up to the surface by the bubbles, influencing the droplet composition.

The study's authors state that many of these compounds contribute to the aroma of the champagne, and the droplets dispersed by the bursting of the bubbles are therefore vital for both the aroma and flavour of the wine.

These are, of course, merely a selection of the many compounds found in champagne. If you want to learn more about champagne's chemistry, check out the recent video by the ACS Reactions team, or take a look through some of the links to further reading provided at the foot of the page.

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You set your oven to 375 degrees Fahrenheit, just like your Grandma's perfect cookie recipe says. And 12 minutes later, they taste nothing like hers.

Don't blame yourself right away. Your oven might not be heating to the proper temperature.

Before you spend money on replacement parts or on a thermometer to hang inside your oven, try this simple experiment from the American Chemical Society's Reactions YouTube page to find out if that really is the problem.

All you need is some aluminum foil and table sugar.

Steps:

1. Heat the oven to 350 degrees Fahrenheit, and wait for it to come to temperature.
2. Form little boats out of the aluminum foil, about the size of your fist.
3. Place a spoonful of table sugar in each boat.
4. Bake the first boat for 15 minutes, then take it out.
5. Raise the oven temperature to 375 degrees Fahrenheit, and wait for it to heat up.
6. Bake the second boat for 15 minutes, then take it out.

If your oven is at the right temperature, the first sugar sample should still be white, and the second should be golden brown and melty.

This is because the process of caramelization begins above 356 degrees Fahrenheit, and sugar begins melting at 367 degrees Fahrenheit.

So if both are white, your oven is running cool — it is heating to a lower temperature than what you're setting it to.

And if both are caramelized, it's running hot and heating to a higher temp than set by the dial.

Now you can adjust your oven temperature up or down, depending on how the experiment turned out.

Here's the full video from the ACS:

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As the clock counts down to midnight on New Year's Eve, many of you will probably be engaging in a time-honored tradition: Getting wasted.

But those celebratory libations probably won't feel so good the next morning, when the dreaded hangover sets in. So what exactly causes a hangover, and is there any way to keep it at bay?

Luckily, the smart people at the American Chemical Society (ACS) put together a handy video that explains the chemistry of hangovers.

The science of hangovers

It's no surprise the hangovers are caused by drinking too much alcohol. The main symptoms include fatigue, dehydration, headaches, nausea and vomiting, poor sleep, and dizziness.

According to the ACS video, here's what's going on your body when you've had a little too much to drink: Alcohol is broken down by two enzymes, or proteins, in the liver — ADH and ALDH. ADH converts alcohol (ethanol) into a toxin compound called acetaldehyde, which is a known carcinogen. Then, ALDH breaks acetaldehyde down into acetate, which then breaks down into carbon dioxide and water.

High levels of acetaldehyde may lead to impaired thinking, memory loss, dry mouth, and other symptoms, research suggests.

Alcohol is also a notorious diuretic— it makes you have to use the bathroom more, because it interferes with the production of a hormone called vasopressin, which controls how much water your kidneys excrete.

Drinking can also mess with your sleep. Alcohol gets in the way of two important brain chemicals involved in sleep and wakefulness. It boosts the effects of GABA, a chemical that inhibits or blocks nerve signals, and suppresses the effects of glutamate, a chemical that ramps up brain activity.

As a result, alcohol makes you sleepy. But it also stops you from having as much rapid eye movement, or REM, sleep, which is important for recharging your mental batteries.

The nausea and vomiting many people feel after drinking too much comes from the fact that alcohol can damage the mucus lining in your stomach that seals off the strongly acidic contents inside.

So, is there a way to avoid all this pain and suffering?

Preventing hangovers

The ACS video offers a few tips that may help with a hangover, though you may want to take these with a grain of salt given some recent research (details on that below):

• Eat eggs: They contain high levels of an amino acid called L-cysteine, which can help break down acetaldehyde.
• Don't drink anything at least an hour and a half before going to bed.
• Drink one glass of water for every serving of alcohol (one shot, one beer, one glass of wine) you consume to help prevent dehydration.
• Eat a heavy meal before drinking, especially one rich in proteins, which may slow down the absorption of alcohol and help protect your stomach lining.

Despite these tips, keep in mind that a recent study reported by BBC News suggested that eating food and drinking lots of water had no effect on preventing a hangover.

For that study, a team of Dutch researchers asked 826 students to describe their most recent drinking experience that led to a hangover, and whether they'd eaten or drunk anything before. The results suggested that food and drink had no effect on the severity of the hangovers they reported.

The only sure-fire way to avoid a hangover is to not drink too much in the first place, the researchers said.

Watch the full ACS video here:

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After new year celebrations, you might well be nursing a sore head this morning after a few drinks too many. This is a chemical consequence of consuming alcoholic beverages, but it’s one that, surprisingly, we still don’t fully understand.

There are, however, a number of chemical suspects that have been identified as contributing to the symptoms of a hangover; here, we take a look at each in turn, and the evidence for their contribution.It’s worth clarifying, before discussing the factors causing a hangover, that there’s a significant number of things that can affect a hangover’s severity.

We all know that one person who enviably claims never to experience hangovers; studies have shown that genetic factors could go some way towards explaining this, and health, age, and sleep can all also have effects on how bad your hangover is.

In general, most studies have shown that reaching a blood alcohol concentration of 0.1% is required for most people to experience the symptoms of a hangover the following day, though obviously this will still be variable from person to person.

It’s also generally accepted that the higher your peak blood alcohol concentration (simple translation: the more alcohol you drink), the worse your hangover symptoms are likely to be.

It’s commonly assumed that these symptoms are largely down to dehydration after a night of drinking. It’s widely thought that alcohol does have a diuretic effect on the body, causing an increase in urination, and therefore water loss (though there’s some debate as to the magnitude of this effect).

It does this because it lowers the level of the antidiuretic hormone (ADH) vasopressin, which usually acts to increase the retention of water in the kidneys. It therefore leads to increased urination and water loss.

Although dehydration is a commonly assumed cause of a hangover, it’s actually the case that there’s little research to support this.

Whilst it’s certainly possible that it contributes in part to some of the symptoms, and drinking a few glasses of water after a night of drinking might help alleviate symptoms such as a dry mouth and thirst, there’s little evidence that this also helps reduce the presence or severity of hangover symptoms.

Another hangover suspect is a compound produced by the metabolism of alcohol. Alcohol (more specifically, ethanol) is broken down by enzymes in the liver into acetaldehyde, which is subsequently broken down by another enzyme into acetate. Acetate can be broken down into carbon dioxide and water.

Your body is capable of breaking down alcohol at a rate of around one unit (8 grams or 10 millilitres of pure alcohol) per hour, though of course this rate will vary marginally from person to person.

Acetaldehyde is the particular compound that’s been implicated in hangovers. It’s a toxic compound, which is usually broken down very quickly into acetate.

However, the enzyme that converts ethanol to acetaldehyde works faster than that which converts acetaldehyde to acetate, leading to a build-up of acetaldehyde if you have several drinks in a row.

It’s been suggested that acetaldehyde’s toxic effects on cells may play a part in the development of hangover symptoms, particularly nausea, sweating, increased heart rate and headache.

There’s still no definite answer one way of the other as to the extent of acetaldehyde’s involvement, though studies have found that the concentration of acetaldehyde in the blood of test subjects didn’t show significant correlation with hangover severity. It may well play a part, but it seems likely that it isn’t the major player.

Other studies have suggested that the problem may lie with compounds other than alcohol in the drinks you were drinking the night before. Most alcoholic drinks will contain a whole range of other chemical compounds as well as ethanol, and these compounds are generally referred to as congeners.

Different drinks have different levels of congeners; for example, brandy, red wine and whiskey have much higher congener levels that drinks such as beer, vodka and gin. It’s suggested that higher congener levels could increase the severity of hangover symptoms the next day.

Potential major players when it comes to congeners are alcohols other than ethanol. These are present in much lower quantities, but can include methanol. Whether you’re a chemist or not, you’ve likely heard of methanol, and you might be surprised to learn that it’s actually found in small quantities in most alcoholic drinks, as a byproduct of distillation or brewing processes.

Though methanol is dangerous to ingest in large amounts, it’s not problematic in the amounts found in these alcoholic drinks – though it may make a contribution to hangover severity.

Methanol is actually broken down in the body by the exact same enzymes that help to break down ethanol. However, these enzymes are more specific for ethanol; that is, if there’s any ethanol around, they prefer to break it down over methanol.

As such, the methanol hangs around until your body’s finished breaking down ethanol. It’s been suggested that its breakdown could account for some hangover effects, as it’s metabolised into toxic formaldehyde and formic acid.

The delay in its breakdown could help explain the delayed action of hangovers, and also why ‘hair of the dog’ might help: providing your body with ethanol to break down instead essentially ‘distracts’ the enzymes from breaking down methanol.

It’s generally thought that congeners can have a significant effect on the severity of a hangover, though they still don’t explain all of the symptoms. More recent research is now suggesting that our immune systems may also have a part to play in a hangover’s genesis.

Studies have shown that alcohol can have an effect of cytokines, small proteins produced by cells in the body that help control the immune system and fight disease.

It can increase the concentrations of certain cytokines in the body, causing ‘imbalance’ in the immune system that could result in symptoms such as headache, fatigue, and memory loss. Changes in hangover severity have been significantly correlated with the increased levels of some of these cytokines.

To draw things to a close, it’s clear that there’s still a lot more work to be done on our knowledge of hangovers; a phenomenon the majority of us experience, but one that we still don’t fully understand.

Because of this, it’s hard to suggest an effective hangover cure, and consequently there’s no cure that’s been shown to be particularly efficacious in studies. In the meantime, it looks like there’s little more to do on New Year’s Day than recline on the sofa for most of the day and wait for the symptoms to pass!

There’s more on hangover chemistry, including whether mixing drinks really worsens your hangover, in the Compound Interest book on the chemistry of food and drink, available now!

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Officials from the International Union of Pure and Applied Chemistry (IUPAC) have confirmed the discovery of elements 113, 115, 117, and 118, announcing that there is now enough evidence to give them permanent places on the periodic table, which means they'll also need new, official names.

You won't find these four elements in nature — they are synthetic elements that can only be produced in the lab, and because they decay in a matter of seconds, their existence has been extremely difficult to confirm.

Until now, elements 113, 115, 117, and 118 had temporary names and positions on the seventh row of the periodic table because scientists have struggled to create them more than once.

"For over seven years we continued to search for data conclusively identifying element 113, but we just never saw another event," Kosuke Morita from RIKEN in Japan said of one of the four elements. "I was not prepared to give up, however, as I believed that one day, if we persevered, luck would fall upon us again."

Morita's team has been credited with the confirmed discovery of element 113, which means they've won the naming rights too. Until now, the element been known by the temporary name, ununtrium, and temporary symbol Uut.

The three remaining elements, 115, 117, and 118 - known temporarily as ununpentium (Uup), ununseptium (Uus), and ununoctium (Uuo), respectively — will also get new names.

The IUPAC has announced that a team of US and Russian researchers have fulfilled the criteria for proving the existence of the remaining three elements, 115, 117, and 118, and will be invited to propose permanent names and symbols. 

"The chemistry community is eager to see its most cherished table finally being completed down to the seventh row," Jan Reedijk, president of the Inorganic Chemistry Division of IUPAC, said last week.

The organization advises that the new elements can be named after a mythological concept, a mineral, a place or country, a property, or a scientist, and will be presented for public review for five months before a final decision about the new official name and symbol is made.

While reports on the confirmation of elements 115, 117, and 118 are yet to be published, details of element 113's discovery have been reported in the Journal of Physical Society of Japan.

The RIKEN researchers describe how in 2003, they began bombarding a thin layer of bismuth with zinc ions traveling at about 10 percent the speed of light, and according to theory, the reaction should occasionally produce an atom of element 113.

In 2004 and 2005, the team saw signs of dubnium-262 (element 105), which is believed to be the decay product of element 113, but this was not enough evidence to prove its existence.

"[T]he group performed a new experiment, where a sodium beam was collided with a curium target, creating borhium-266 and its daughter nucleus, dubnium-262,"explains a press release. "With this demonstration, the grounds for a stronger claim were laid. They just needed to wait to see an atom decaying through the alpha chain rather than spontaneous fission."

It wasn't until 2012 that the team achieved this, and it took almost four years for the IUPAC to wade through the scientific literature and confirm that the evidence met their criteria for the discovery of elements.

"Now that we have conclusively demonstrated the existence of element 113,"says lead RIKEN researcher, Kosuke Morita, "we plan to look to the uncharted territory of element 119 and beyond, aiming to examine the chemical properties of the elements in the seventh and eighth rows of the periodic table, and someday to discover the Island of Stability."

We can't wait to see what the new names will be.

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If your life’s ambition is to become very, very rich, consider getting into the business of producing endohedral fullerenes - the world’s most expensive material.

Scientists at Oxford University in the UK announced that a spin-off lab called Designer Carbon Materials is now producing endohedral fullerenes, and theyrecently sold off their first sample of the material to the tune of $US 32,000 for 200 micrograms (1 microgram = one-millionth of a gram), which is about one-fifteenth the weight of a snowflake, or one-third the weight of a human hair.

First discovered in 1985, endohedral fullerenes are spherical carbon nanostructures that consist of a sturdy fullerene cage made from 60 carbon atoms, inside which the atoms of non-metals or simple molecules, such as nitrogen, phosphorus, and helium, are trapped.

These things aren’t just outrageously expensive curiosities - when they contain nitrogen atoms, they actually have the potential to change how we keep time, because of their extra long electron spin lifetime.

Scientists are now investigating the possibility of using them in atomic clocks - the most accurate time-keeping systems in the world - and the Oxford team expects that in the future, they could be used to make all kinds of devices more accurate than ever.

This is because endohedral fullerenes have the potential to downsize atomic clocks from the size of a cabinet to a microchip, so we could install them in our phones or integrate them with our GPS devices, for example.

If we can figure out how to do that, says Doug Bolton at The Independent, we could have GPS devices that are accurate to within 1 millimetre. That’s pretty mind-blowing, when you consider that current GPS devices are accurate to around 1 to 5 metres.

"At the moment, atomic clocks are room-sized. This endohedral fullerene would make it work on a chip that could go into your mobile phone," Lucius Cary, director of the Oxford Technology SEIS fund - which holds a minor stake in Designer Carbon Materials - told Rebecca Burn-Callander at The Telegraph.

"There will be lots of applications for this technology,"he added. "The most obvious is in controlling autonomous vehicles. If two cars are coming towards each other on a country lane, knowing where they are to within 2 metres is not enough, but to 1 mm it is enough."

The only other material on Earth that could rival the astronomical cost of endohedral fullerenes is antimatter, which NASA estimates would cost aboutUS$61 trillion per gram, but no one’s in the business of producing antimatter to sell off commercially just yet.

We’re still several years away from mini atomic clocks going into our portable devices, but Designer Carbon Materials founder, Kyriakos Porfyrakis, told Andrii Degeler at Ars Technica that the consortium of UK and US researchers that bought their first sample of endohedral fullerene is on the case.

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Believe it or not, not all blood is red. The life-giving fluid actually comes in five different colors, depending on what animal you're talking about. 

The different colors reflect different chemicals in special proteins in the blood called plasma proteins that carry essential nutrients throughout the body. But interestingly, some of these animals don't reveal their true colors until you cut them open. That's because some of the chemicals change color when exposed to oxygen.

Check out this infographic to learn more about the five crazy colors of blood:

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A Reddit user is gradually uploading the 5,000-page court case file of Steven Avery, and his digital haul now includes four crucial documents submitted by the FBI during Avery's murder trial in 2007.

The FBI's reports are critical because they might have turned jurors against Avery "and maybe not fairly," Dean Strang, one of Avery's defense lawyers during his trial, told The Daily Beast in January.

Avery, a resident of Manitowoc County, Wisconsin, was arrested in November 2005 as a suspect in the disappearance of 25-year-old photographer Teresa Halbach. Police later found Halbach's bloodied car and burned bones on Avery's property and, after a lengthy trial, jurors in 2007 delivered a guilty verdict, leading to Avery's sentence of life in prison without parole.

Attention to Avery's case has exploded due to Netflix's 10-part series "Making a Murderer," a true-crime documentary that follows Avery and his family before, during, and after that trial.

The show has since amassed countless fans and a community of Reddit users, including Skipp Topp, who's digitizing Avery's enormous case file with crowdfunding help and uploading the PDFs to StevenAveryCase.org. (Reddit user Emmerline is also uploading court documents.)

Conspiracy theory

Many fans of the show are particularly obsessed with a controversial idea that filmmakers played up in episode seven: that blood stains found in Halbach's car may have been planted by police to help incriminate Avery.

Avery's lawyers argued that the blood stains, which matched Avery's DNA profile, could have been extracted from a vial of Avery's blood collected in 2002 and stored in a police evidence room.

Framing by police is never a popular defense strategy, but in this case the idea wasn't too far-fetched for a few reasons.

Shortly before his arrest as a suspect in Halbach's murder, Avery filed a $36 million civil lawsuit against the county that put him in jail for 18 years on a rape charge. He sued because DNA evidence exonerated him from the 1985 crime in 2003. (That's where the 2002 vial of blood in the evidence room came from; it was used to verify Avery's DNA.)

When the defense team examined that blood vial years later, it showed possible signs of tampering, including a broken evidence seal and a hole in the tube's cap.

Several members of the local police force were also being deposed in Avery's lawsuit as late as October 2005. Those deposed included two officers who collected evidence linking Avery to the scene of Halbach's murder.

But a conspiracy theory and a potentially tampered vial of blood wasn't enough for Avery's defense team to go on; the lawyers had to show the blood stains in the car came from the vial in police custody.

A search for EDTA

This is where the FBI's blood stain analysis reports, filed in February 2007, come in to play.

Almost every vial of blood contains a preservative called EDTA (short for ethylenediaminetetraacetic acid). It's a chemical that isn't found in human blood and prevents it from clotting. Mixed in a sealed vial, EDTA can keep a blood sample liquid for years.

The court asked the FBI to test the samples for the presence of EDTA, and the results came back in the middle of Avery's trial.

Patrick Willis, the presiding judge during the trial, was shown the FBI's reports during a closed hearing without any jurors. Willis ultimately deemed the information admissible as evidence — something that still frustrates Strang today.

"We had no chance at that point to do independent testing, or even to react terribly well to it because we're being handed the report during trial and then, boom—[expert witness] Marc LeBeau is on the stand the next morning," Strang told The Daily Beast.

In a testimony that was damning to Avery's defense, LeBeau, an FBI forensic scientist, said that the blood swabs from Halbach's car showed no signs of the preservative — or planted evidence.

The FBI's reports

The FBI's four EDTA-related reports are embedded below.

Until this month, these documents were never publicly posted online and in plain view of outside forensic experts.

Tech Insider has reached out to several scientists to review the documents and offer their feedback.

We've also reached out to Dean Strang, who did not return our queries in time for this story. Jerry Buting replied to an initial query but hasn't responded to our followup queries. Marc LeBeau directed our interview request to FBI public affairs, which denied it (as well as another interview request).

When we asked the FBI for more details about its EDTA testing process, a bureau representative told Tech Insider that "the Avery protocol was based off [a] 1997 study" in the Journal of Analytical Toxicology, "but was updated based on technology advancements." When we asked for clarification on what "technology advancements" meant, we were told to file a Freedom of Information Act request (which we've done).

If you're a forensic scientist or analytical chemist, and wish to comment on the following documents, please reach out to: dmosher@techinsider.io

SEE ALSO: 11 true-crime documentaries to watch that are as jarring as ‘Making a Murderer’

Trial exhibit 435 — FBI EDTA test

RAW Embed

Source: StevenAveryCase.org/Wisconsin Court System

Trial exhibit 434 — Analysis of EDTA in dried bloodstains

RAW Embed

Source: StevenAveryCase.org/Wisconsin Court System 

Trial exhibit 441 — Comparison of mass spectra FBI lab

RAW Embed

Source: StevenAveryCase.org/Wisconsin Court System 

Christopher H. Hendon, a postdoctoral fellow in chemistry at MIT, was sitting in a coffee shop near his graduate school in the UK a few years ago when he overheard a conversation between two frustrated baristas. 

"They were having problems with coffee that tasted good one day and not another," he said. While that's a frustrating mystery for a coffee shop with exacting standards, "from a chemistry point of view, that's an interesting problem."

Specialty coffee shops can control where their beans come from and how they are roasted, ground, and brewed, but there's one crucial factor that can throw a wrench into the whole operation, Hendon found: the water.

To truly brew a perfect cup, it's not enough to know what kind of beans you're working with. You also have to know about the chemistry of the water.

What's in the water?

Most people know that water can be "hard" (full of minerals like magnesium) or "soft" (most distilled water falls into this category). But there's also natural variation.

Here's a map of the US that shows how water hardness varies from place to place, although it can also vary over time:

When Hendon teamed up with baristas Lesley Colonna-Dashwood and Maxwell Colonna-Dashwood — who won the 2015 UK Barista Championship — they found that different kinds of "hardness" in water bring out significantly different flavors in coffee. (Hendon ran the experiments using a computer, while the coffee shop owners actually brewed sample cups.)

So why does the water matter?

Roasted coffee beans are packed with compounds like citric acid, lactic acid, and eugenol (a compound that adds a "woodsy" taste). All of those compounds occur in varying levels in beans, giving coffee its complex and highly varied flavors.

Water, meanwhile, has a complexity all its own. When you turn on a tap, you're not just getting H₂O, but different levels of ions like magnesium and calcium. (Higher levels = "harder.")

Here's the key: Some of the compounds in hard water are "sticky," glomming onto certain compounds in coffee when they meet in your coffee-making device. The more eugenol the water hangs on to, for example, the woodsier the taste of your coffee will be. 

Magnesium is particularly sticky, meaning water that's high in magnesium will make coffee with a stronger flavor (and higher levels of caffeine). Hard water can also have high levels of bicarbonate, though, which Hendon found could lead to more bitter flavors coming through.

But while hard water is a bit of a gamble, depending on which minerals are in the highest concentrations, soft water had no benefits at all. Its chemical composition "results in very bad extraction power," Hendon explained.

Soft water often contains sodium, but that has no flavor stickiness (for good or bad flavors), Hendon found. That means that if you use the exact same beans, you'll get a much stronger flavor if you use high-magnesium "hard water" in place of distilled or softened water.

The study was published in the Journal of Agricultural and Food Chemistry, and eventually turned into a book that explains why coffee lovers need to worry about more than just good beans. "Water can transform the character of a coffee," the chemist-barista team explains.

A chemically perfect cup

Unlike Hendon, the average coffee lover is not also a chemist. You can't easily alter the composition of your water supply every time you want a delicious cup. 

But there's good news: You don't have to. Understanding that the kind of water you use can change the kind of coffee you get will help you on the path to the perfect brew — even if you're stuck with whatever comes out of your kitchen tap.

To start, you can look up the hardness of your water online (New Yorkers can call 311), and then buy beans —depending on what you learn — that are meant for "soft" or "hard" water. (Hendon said that's the kind of thing upscale roasters will know.) 

Sure, you won't know the specific water compounds that will pair perfectly with a particular roast — that's the kind of rigorous coffee science Hendon and Colonna-Dashwood relied on to place fifth overall in the World Barista Championship — but you'll already be a step ahead if you buy from a local roaster.

When roasters test their beans, they do so using local water, so you can at least assume that locally-roasted coffee is optimized for the chemistry of your water. That's the opposite of Starbucks, which, according to Hendon, uses totally pure water to ensure a completely uniform taste across the country.

"A lot of dark art has gone into coffee," said Hendon. "This is some real science."

Join the conversation about this story »

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Christopher H. Hendon, a postdoctoral fellow in chemistry at MIT, was sitting in a coffee shop near his graduate school in the UK a few years ago when he overheard a conversation between two frustrated baristas. 

"They were having problems with coffee that tasted good one day and not another," he said. While that's a frustrating mystery for a coffee shop with exacting standards, "from a chemistry point of view, that's an interesting problem."

Specialty coffee shops can control where their beans come from and how they are roasted, ground, and brewed, but there's one crucial factor that can throw a wrench into the whole operation, Hendon found: the water.

To truly brew a perfect cup, it's not enough to know what kind of beans you're working with. You also have to know about the chemistry of the water.

What's in the water?

Most people know that water can be "hard" (full of minerals like magnesium) or "soft" (most distilled water falls into this category). But there's also natural variation.

Here's a map of the US that shows how water hardness varies from place to place, although it can also vary over time:

When Hendon teamed up with baristas Lesley Colonna-Dashwood and Maxwell Colonna-Dashwood — who won the 2015 UK Barista Championship — they found that different kinds of "hardness" in water bring out significantly different flavors in coffee. (Hendon ran the experiments using a computer, while the coffee shop owners actually brewed sample cups.)

So why does the water matter?

Roasted coffee beans are packed with compounds like citric acid, lactic acid, and eugenol (a compound that adds a "woodsy" taste). All of those compounds occur in varying levels in beans, giving coffee its complex and highly varied flavors.

Water, meanwhile, has a complexity all its own. When you turn on a tap, you're not just getting H₂O, but different levels of ions like magnesium and calcium. (Higher levels = "harder.")

Here's the key: Some of the compounds in hard water are "sticky," glomming onto certain compounds in coffee when they meet in your coffee-making device. The more eugenol the water hangs on to, for example, the woodsier the taste of your coffee will be. 

Magnesium is particularly sticky, meaning water that's high in magnesium will make coffee with a stronger flavor (and higher levels of caffeine). Hard water can also have high levels of bicarbonate, though, which Hendon found could lead to more bitter flavors coming through.

But while hard water is a bit of a gamble, depending on which minerals are in the highest concentrations, soft water had no benefits at all. Its chemical composition "results in very bad extraction power," Hendon explained.

Soft water often contains sodium, but that has no flavor stickiness (for good or bad flavors), Hendon found. That means that if you use the exact same beans, you'll get a much stronger flavor if you use high-magnesium "hard water" in place of distilled or softened water.

The study was published in the Journal of Agricultural and Food Chemistry, and eventually turned into a book that explains why coffee lovers need to worry about more than just good beans. "Water can transform the character of a coffee," the chemist-barista team explains.

A chemically perfect cup

Unlike Hendon, the average coffee lover is not also a chemist. You can't easily alter the composition of your water supply every time you want a delicious cup. 

But there's good news: You don't have to. Understanding that the kind of water you use can change the kind of coffee you get will help you on the path to the perfect brew — even if you're stuck with whatever comes out of your kitchen tap.

To start, you can look up the hardness of your water online (New Yorkers can call 311), and then buy beans —depending on what you learn — that are meant for "soft" or "hard" water. (Hendon said that's the kind of thing upscale roasters will know.) 

Sure, you won't know the specific water compounds that will pair perfectly with a particular roast — that's the kind of rigorous coffee science Hendon and Colonna-Dashwood relied on to place fifth overall in the World Barista Championship — but you'll already be a step ahead if you buy from a local roaster.

When roasters test their beans, they do so using local water, so you can at least assume that locally-roasted coffee is optimized for the chemistry of your water. That's the opposite of Starbucks, which, according to Hendon, uses totally pure water to ensure a completely uniform taste across the country.

"A lot of dark art has gone into coffee," said Hendon. "This is some real science."

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Have you ever noticed the clink-clank of a tiny object rattling around the inside of an empty Guinness bottle or can?

That little gadget is called a "widget," and you should be thankful for it. It's making your beer taste like it was just poured fresh from the tap.

A widget is a hollow, spherical piece of plastic with a tiny hole in it — it looks like a little ping pong ball.

During the canning process, brewers add pressurized nitrogen to the brew, which trickles into the hole along with a little bit of beer. The entire can is then pressurized.

When you open the can, the pressure inside the can drops to equalize with the pressure in the room. Since the pressure inside the widget is still much higher than the pressure in the beer around it, the nitrogenated beer from inside the widget squirts into the beer — providing a burst of tiny bubbles of nitrogen gas that rise to the top of beer, giving it a thick, creamy head you'd get straight from the tap.

Guinness brewers first patented the idea of the widget in 1969, but it wasn't until 20 years later in 1989 when they released their first-generation widget, which was a flattened sphere that sat at the bottom of the can. This little piece of plastic did its job well when serving the beer cold, but when served warm, the beer exploded everywhere after the can was cracked open.

In 1997, Guinness released the floating, spherical widget you can see in cans today — which they call the "Smoothifier"— to fix this problem.

Breweries typically use carbon dioxide to give a beer its quintessential bitter fizz, but when a drink calls for a sweeter, silkier experience — such as the experience you get when drinking a Guinness — brewers infuse the ale with nitrogen rather than with carbon dioxide. Nitrogen bubbles are smaller than CO₂ bubbles, so the resulting head and taste is smoother and more delicate.

Nitrogen gas also doesn't easily dissolve in water, so when you crack open a beer, most of the gas is released into the air but the foamy bubbles in the head still remain. This — along with the smaller bubbles — gives the brew a thicker, more velvety "mouthfeel" without the acidic bite of carbonation with CO₂.

Because of the fleeting nature of nitrogen gas in liquid, it's really hard to maintain tasty levels of the gas in packaged beers once you open them.

"With nitrogen, you would require way higher (and dangerous) levels of pressure, and still loose plenty of nitrogen (and beer due to foaming) during packaging," Xavier Jirau, scientific advisor of the homebrew club The Brewminaries, told Tech Insider via email. "In order to deal with this issue, brewers got little creative, and there is where Guinness plastic widgets come into play."

The popularity of widgets have caught on since Guinness introduced them in the late 80s. Other beers such as Old Speckled Hen, Young's Double Chocolate Stout, Murphy's Stout, and Boddingtons Pub Ale all have widgets in their cans.

So go crack a cold one and thank that little plastic sphere for delivering your delicious, velvety brew.

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NOW WATCH: Is draft beer better than bottled beer?

A Reddit user is gradually uploading the 5,000-page court case file of Steven Avery, and his digital haul now includes 14 crucial documents submitted by the FBI during Avery's murder trial in 2007.

The FBI's reports — some 700 pages in total — are critical because they might have turned jurors against Avery "and maybe not fairly," Dean Strang, one of Avery's defense lawyers during his trial, told The Daily Beast in January.

Avery, a resident of Manitowoc County, Wisconsin, was arrested in November 2005 as a suspect in the disappearance of 25-year-old photographer Teresa Halbach. Police later found Halbach's bloodied car and burned bones on Avery's property and, after a lengthy trial, jurors in 2007 delivered a guilty verdict, leading to Avery's sentence of life in prison without parole.

Attention to Avery's case has exploded due to Netflix's 10-part series "Making a Murderer," a true-crime documentary that follows Avery and his family before, during, and after that trial.

The show has since amassed countless fans and a community of Reddit users, including Skipp Topp, who's digitizing Avery's enormous case file with crowdfunding help and uploading the PDFs to StevenAveryCase.org.

All 14 FBI evidence exhibits, which are embedded at the end of this post, deal with the presence of a blood preservative called EDTA (short for ethylenediaminetetraacetic acid).

"There are around 700 pages in total, the vast majority being charts and graphs from exhibit 446," Topp told Tech Insider. "This means everything related to EDTA is now online."

Conspiracy theory

Many fans of the show are particularly obsessed with a controversial idea that filmmakers played up in episode seven: that blood stains found in Halbach's car may have been planted by police to help incriminate Avery.

Avery's lawyers argued that the blood stains, which matched Avery's DNA profile, could have been extracted from a vial of Avery's blood collected in 2002 and stored in a police evidence room.

Framing by police is never a popular defense strategy, but in this case the idea wasn't too far-fetched for a few reasons.

Shortly before his arrest as a suspect in Halbach's murder, Avery filed a $36 million civil lawsuit against the county that put him in jail for 18 years on a rape charge. He sued because DNA evidence exonerated him from the 1985 crime in 2003. (That's where the 2002 vial of blood in the evidence room came from; it was used to verify Avery's DNA.)

When the defense team examined that blood vial years later, it showed possible signs of tampering, including a broken evidence seal and a hole in the tube's cap.

Several members of the local police force were also being deposed in Avery's lawsuit as late as October 2005. Those deposed included two officers who collected evidence linking Avery to the scene of Halbach's murder.

But a conspiracy theory and a potentially tampered vial of blood wasn't enough for Avery's defense team to go on; the lawyers had to show the blood stains in the car came from the vial in police custody.

A search for EDTA

This is where the FBI's blood stain analysis reports, filed in February 2007, come in to play.

Almost every vial of blood contains a preservative called EDTA. It's a chemical that isn't found in human blood and prevents it from clotting. Mixed in a sealed vial, EDTA can keep a blood sample liquid for years.

The court asked the FBI to test the samples for the presence of EDTA, and the results came back in the middle of Avery's trial.

Patrick Willis, the presiding judge during the trial, was shown the FBI's reports during a closed hearing without any jurors. Willis ultimately deemed the information admissible as evidence — something that still frustrates Strang today.

"We had no chance at that point to do independent testing, or even to react terribly well to it because we're being handed the report during trial and then, boom—[expert witness] Marc LeBeau is on the stand the next morning," Strang told The Daily Beast.

In a testimony that was damning to Avery's defense, LeBeau, an FBI forensic scientist, said that the blood swabs from Halbach's car showed no signs of the preservative — or planted evidence.

The FBI's reports

All 14 of the FBI's EDTA-related reports — exhibits 433 through 446 — are embedded below.

Ten of them were not publicly posted online and in plain view of outside forensic experts until this week. (We wrote about the first four documents here.)

These 14 FBI exhibits listed in the court record of events include a "white binder with lab sheets and reports" (more than 630 pages long), an "EDTA stability study," a "graph of Poss. Cont. B Q49 sample," an approved EDTA testing order, and more.

Tech Insider has reached out to several scientists and lab technicians to review the documents and offer their feedback.

Strang declined to comment on Avery's case deferring to fellow defense laywer Jerry Buting. Buting replied to an initial query but hasn't responded to our followup queries.

The FBI's LeBeau directed our interview request to FBI public affairs, which denied it (in addition to another interview request).

When we initially asked the FBI for more details about its EDTA testing process, a bureau representative told Tech Insider that "the Avery protocol was based off [a] 1997 study" in the Journal of Analytical Toxicology, "but was updated based on technology advancements." When we asked for clarification on what "technology advancements" meant, we were told to file a Freedom of Information Act request (which we've done).

If you're a forensic scientist, analytical chemist, or lab technician, and you wish to comment on the following documents — especially exhibit 446, which covers the lab reports, methods, validation, and more — please reach out to: dmosher@techinsider.io

Trial exhibit 433 — CV of Marc LeBeau

RAW Embed

Source: StevenAveryCase.org/Wisconsin Court System

Trial exhibit 434 — Analysis of EDTA in Dried Bloodstains

RAW Embed

Source: StevenAveryCase.org/Wisconsin Court System 

Trial exhibit 435 — FBI EDTA Test

RAW Embed

Source: StevenAveryCase.org/Wisconsin Court System

If you've finished watching Netflix's true-crime documentary series "Making a Murderer," you have a lot of questions.

Above all you are probably wondering: What is the deal with the FBI's blood test for EDTA?

How sensitive was the test? Did the results leave any room for doubt about planted evidence? And were the FBI's reports as inconclusive as Steven Avery's lawyers made them sound?

These are important questions that an untold number of very passionate fans are still grappling with, weeks after the show's rise to prominence.

So Tech Insider got to work.

We contacted the FBI and Avery's defense team; corresponded with forensic scientists, analytical chemists, and lab technicians; and reviewed more than 700 pages of EDTA-related evidence uploaded by Reddit user Skipp Topp at StevenAveryCase.org.

One of the more significant sources we heard back from was Bruce McCord, who leads a forensic research group at Florida International University.

What McCord had to say about the FBI's lab reports — which may have turned the jury against Avery— was strong if not blunt.

"It looks reasonable to me," McCord told Tech Insider of the FBI's work in an email. "No mystery."

In other words: A potentially damning conclusion for Avery's 2007 defense.

The FBI test did not come out of nowhere

McCord is not your average forensic scientist.

He not only specializes in blood analysis but has important pre-history in regard to the Avery case. That's because in the mid-1990s he helped pioneer the technique that the FBI later used in 2007.

McCord came into our view because an FBI spokesperson pointed us to a 1997 study in the Journal of Analytical Toxicology, which names McCord as the second author.

McCord and his colleagues' eight-page article is a thorough defense to a blood evidence controversy from the 1995 OJ Simpson trial.

The defense team for Simpson, as with Avery's, argued that police had planted evidence using a vial of preserved blood — of which EDTA (short for ethylenediaminetetraacetic acid) is a smoking gun because it's not found naturally in human blood.

Lab tests showed a very small amount of EDTA in some Simpson-case blood evidence. But some experts believe the chemical came from a test sample, not blood from the crime scene.

The test sample was a positive control to show the lab equipment could easily detect tiny concentrations of EDTA. Yet that positive test could have contaminated the high-tech lab gear, carried over a little EDTA into other samples, and potentially compromised key blood evidence.

McCord and his colleagues' 1997 study lays out the steps to follow — and missteps to avoid inadvertent EDTA contamination — if anyone comes around again with claims of planted blood evidence.

In particular, the study explains how to flush out any residual EDTA from tandem mass spectrometry machine (pictured above). It also suggests EDTA is easily detectable in dried stains of preserved blood that are 2 years old.

The FBI told Tech Insider that "the Avery protocol was based off the 1997 study, but was updated based on technology advancements."

An FBI spokesperson refused to detail what "technology advancements" meant, but logic suggests it's practically the same protocol — just with newer, more sensitive, and more capable equipment.

The limits of sensitivity

But what of the FBI's actual 2007 testing process during the Avery case? Was it sensitive enough to detect EDTA?

"If blood is preserved with EDTA there will be a 'boatload' of it present in a bloodstain sample," McCord said. "The question of sensitivity would only arise if the blood was diluted after it was shed."

McCord noted that at the time of the Simpson case, labs could detect about a thousand times less EDTA than there is in a watered-down sample of preserved blood.

"The problem in the OJ case was that this issue (there was no dilution) was lost because of [...] some relatively poor testimony by the experts for both sides," he said.

Today, he says, "modern methods can easily detect" about a million times less EDTA than exists in preserved blood.

Practically speaking, this is potentially damning to Avery's defense.

It means that if police did plant Avery's EDTA-preserved blood in Halbach's Toyota RAV4, they would have had to dilute it first to avoid detection by a mass-spec machine.

How much dilution? A lot. Roughly a few drops of preserved blood in a volume of liquid the size of a New York City subway car.

Such highly diluted blood would look more like water than a bloodstain. It probably would not have even been visible in Teresa Halbach's car.

A case still under review

McCord says he's still looking over the 14 EDTA-related evidence exhibits from Avery's trial that we sent him, and it may take him awhile. (Exhibit 446, for example — the FBI lab sheets and reports — is a staggering 638 pages long.)

But a preliminary look at the FBI's measurements of EDTA in blood didn't seem to sway him.

"The analyst who made the measurement is highly competent," he said, noting that they tested the equipment with a positive control (the vial of Avery's preserved blood) and a negative control (swabs of car surfaces near the RAV4 bloodstains, but not on them).

McCord is not the only expert we heard from, and we'll dig into those responses in a future post. We'll also note that McCord worked for the FBI for nine years, from 1989 through 1998, but not in 2007 — when the State of Wisconsin asked the bureau for help with the Avery murder trial. So if anyone is qualified to assess the FBI reports that helped put Avery behind bars, it's one of the guys who helped pioneer the test itself.

Dean Strang, one of Avery's defense lawyers in 2007, declined to comment on the case, deferring instead to fellow defense lawyer Jerry Buting. Buting replied to an initial query, but hasn't responded to our followup queries.

The FBI denied multiple Tech Insider interview requests. When we asked for clarification on what a spokesperson meant by "technology advancements" to the 1997 protocol, we were told to file a Freedom of Information Act request, which we've done.

If you're a forensic scientist, analytical chemist, lab technician, or related expert, and you wish to comment on the following documents — especially exhibit 446, which covers the lab reports, methods, validation, and more — please reach out to: dmosher@techinsider.io

SEE ALSO: Steven Avery's brother offers new evidence that could help the 'Making a Murderer' convict

SEE ALSO: Steven Avery just wrote a letter from jail to all his 'Making a Murderer' supporters

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The science behind making a "rubber egg."

Produced by Christine Nguyen and Maya Dangerfield

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Inviting a special someone, a group of friends, or a team of colleagues by for a delicious dinner can be a great way to show off your cooking skills but can also be incredibly stressful.

Here are three techniques, provided by the American Chemical Society's Reactions YouTube series, that can help you make the perfect dinner.

There's also some cool science behind these techniques that are sure to impress any dinner guest as they happily chow down.

1. Don't cry over your onions. Refrigerate them!

Onions are a delicious addition to any guacamole, burrito, stir fry, or casserole. But they come with a price: Your tears.

Every time you cut into an onion, you release compounds called sulfenic acids.

One of these sulfenic acids mixes with other enzymes in the onion that you release during cutting.

This mixture is what then creates the eye-burning, tear-inducing gas, called syn-propanethial-S-oxide.

To protect your eyes, refrigerate onions for at least 30 minutes before chop time. This reduces the onion's tendency to release sulfenic acid. Another option is to cut the onion under water — that way the water absorbs the acid, and not your eyes.

2. Don't cook with a bad, stinky egg.

Rotten eggs not only taste gross but their putrid state gives them a fetid smell that will have any guest running for the hills instead of flocking to the dinner table.

The reason eggs go bad in the first place is because of tiny dimples that dot their shells.

These dimples are actually pores that allow air to flow in and out of the shell so the developing chick within can breathe.

But, the pores also let bacteria in, which feast on the gelatinous embryo inside breaking down proteins and emitting the putrid-scented gas called hydrogen sulphide.

Over time, the gas builds up inside of the egg. To protect your kitchen from a smelly odor, place the egg inside of a glass of water.

If the egg is filled with hydrogen sulphide, it will float to the surface. If the egg sinks, then you and your guest's noses are safe. 

3. Preserve the bright-green color of your cooked vegetables.

Chlorophyll A and B are the two molecules that give vegetables their beautiful, bright-green color.

When you cook the vegetables for a long period of time, the heat breaks down the plant cells in your veggies. As a result, the cells release acids.

Normally, these acids are kept separate from the chlorophyll, but when heated, the acids escape from the plant cells and come into contact with the green molecules.

When this happens, the acids change the chlorophyll molecules' chemical composition, which, in turn, changes the color of your vegetables from a delicious-looking vibrant green to an unappealing dark green.

To prevent this from happening, cook your vegetables for approximately seven minutes. This is long enough to cook them through but not so long that the acids get the chance to do their dirty work.

Hosting a dinner will test you on many levels, and if all else fails, there's always pizza delivery.

CHECK OUT: A popular way of cooking broccoli is leeching potentially cancer-fighting compounds from it

SEE ALSO: Peanuts, pistachios and other 'nuts' that aren’t actually nuts

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Let's face it: Not all nachos are created equal. There are the nachos you make at home and the nachos you buy at the sports stadium or movie theater.

The key difference is the texture of the cheese: Stadium nachos have that magical liquid texture you get from processed cheese product that you just can't replicate from melting shredded cheddar in your microwave or oven.

But thankfully, the experts at the American Chemical Society (ACS) have found a way for you to get that velvety texture in your own kitchen without having to turn to processed cheese.

Aside from cheese, all you need are two key ingredients: Beer and sodium citrate, which you can order online (Ebay sells 4-oz. packages for $4.89).

The way it workst is that sodium citrate works to rearrange the structure of proteins in the cheese that gives natural cheddar its soft, yet solid, texture.

When sodium citrate interacts with the calcium in the cheese proteins, it replaces calcium atoms with sodium atoms, thus restructuring the proteins and transforming the texture from a soft block to a liquid velvet, perfect for pouring on tortilla chips:

Here are the steps to making the ultimate nacho cheese, which you can find in the description below this ACS video:

1. Put a pot on the stove at medium heat.
2. Add one cup of your favorite beer.
3. Add two teaspoons of sodium citrate and stir until dissolved.
4. Bring beer to a simmer and slowly add your favorite cheese, preferably a cheddar, and whisk it in until you've got a smooth, creamy cheese sauce.
5. Take it to the next level by adding your own special ingredient(s). Hot sauce? Peppers? Onions? Whatever floats your boat.
6. Pour over your nachos, or serve as on the side.
7. Become a Superbowl snack legend.

Check out the full ACS video on YouTube or below:

CHECK OUT: Peanuts, pistachios and other 'nuts' that aren’t actually nuts

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There are over 80,000 chemicals on the market in the US, and the Environmental Protection Agency has only banned nine. 

The EPA has had the power to regulate harmful chemicals under the Toxic Substances Control Act (TSCA) since 1976. But it has actually used this power only a handful of times. 

This is partly because the TSCA makes it pretty difficult for the EPA to regulate industry. The law only lets the EPA test a chemical to find out if it is toxic if companies have already shown the agency that the substance causes harm. 

Of course, companies aren't exactly motivated to tell the EPA that one of their products is harmful — they want to make a profit, not create more regulatory hoops to jump through. 

These are the five existing chemicals that were around before the Act went into effect that the EPA has deemed harmful, plus the four new chemicals that came on the market after TSCA and have since been banned. 

Most of them have really long chemical names, so we've also included what they were used for and how they can be toxic. 

1. Polychlorinated Biphenyls (PCBs)

The EPA banned PCBs in 1978 because they are toxic to humans, animals, and some plants, and they build up in the environment. 

Studies showed that they could cause cancer in mice and rats. 

PCBs were mostly used in electrical equipment, transformers, and hydraulics, but also in applications like plasticizers and fire retardants. 

2. Fully Halogenated Chlorofluoroalkanes

These chemicals were a major part of aerosol sprays, until we figured out they were depleting the ozone layer. 

They were also popular in air conditioning units, refrigeration, fire suppression, and insulation.

The EPA banned Fully Halogenated Chlorofluoroalkanes in 1978 to help protect the ozone layer, which shields us from harmful UV rays that can cause skin cancer. 

3. Dioxin

The EPA banned dioxins, an extremely harmful class of about 75 chemicals, in 1980. 

One of the worst of them, 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), was used as an herbicide, and an ingredient in Agent Orange, which US troops sprayed during the Vietnam War. 

Some dioxins can also be a byproduct of burning pulp to make paper, and of burning trash. 

Dioxins in high quantities can cause cancer, and they have been linked to reproductive issues, developmental problems, and immune system damage. 

Commercial brewers put a ton of time and research into ensuring that their packaged beers taste as if they were just poured from the tap.

But the design of a pint glasses has a lot to do with how good a beer tastes as well.

Carefully curved lips and double-walled constructions improve the presentation and drinking experience of beer, but some brewers and manufacturers are taking the design a step further by etching marks or patterns onto the bottoms of their glasses to make the beer bubblier.

This practice is becoming increasingly more common — and perhaps you've had a drink out of one of these glasses without even knowing it.

These rough etchings are called nucleation points, and their job is to disturb the beer when it touches them. This gives the dissolved gas in the liquid something to latch on to and form bubbles, producing a steady stream of the bubbles as they rise from the base.

"Etchings on the bottom of glasses do not improve carbonation, they actually release some carbonation that is already dissolved as the beer hits the surfaces of the etching," Sheri Jewhurst, the “dictator” of the homebrew club The Brewminaries, told Tech Insider via email.

This is similar to what happens when you drop a Mentos tablet into a can of Diet Coke. The gas that has been dissolved in the soda or beer — usually carbon dioxide — is what gives the drink its bubbles. The liquid is bottled under pressure to keep the bubbles in, and when you open the can or bottle, those bubbles start to make their way out of the liquid, giving you a great fizz.

While the gas will create bubbles naturally, you can speed this process along by giving the bubbles something to latch on to. An object with rough ridges or a bumpy surface — the Mentos, for example — can catalyze bubble-making.

In the classic Mentos and Diet Coke experiment, the mint drops into the soda and forms so many bubbles that it creates intense pressure. Those bubbles have nowhere to go but up, causing an eruption.

Nucleated beer glasses don't cause eruptions, but they produce just enough bubbles to rise through the glass to "refresh" your beer, Jewhurst said. Refresh, in this case, means making it fizzier as opposed to flatter, as if were just poured from the tap.

The photo below shows a side-by-side comparison of a glass with nucleation points (left) versus one without them (right). You can see how much more fizzy the drink on the left is.

But this bubble stream effect, while neat in appearance, is not always welcomed.

"I believe there is also a cosmetic appeal in etchings to have little bubbles dancing through your glass," Jewhurst said."However, with highly carbonated beers such as wit beers, having the constant flow of bubbles coming up from the bottom can actually be kind of a nuisance since they are so prolific."

Next time you purchase a pint glass or are at your local pub, check out the inside. If it has the etchings, you know you'll be in for a fizzy ride.

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Diamond is not only one of the most beautiful materials on earth; it's also one of the strongest.

It doesn't trigger an immune response, it can withstand high levels of radiation, and it can act as both an insulator and a conductor of electricity under different conditions.

For these reasons and more, diamonds have incredible potential in electronics, medicine, and manufacturing — especially if we can make them incredibly small.

Researchers from both Penn State and the Queensland University of Technology have created diamond nanothreads, reports MIT Technology Review.

These nanothreads are a shocking three atoms across, according to Scientific American, or about three-tenths of a billionth of a meter.

Scientists create the diamond nanothreads by lining up benzene molecules — which consist of six carbon atoms and six hydrogen atoms arranged in a ring — and smooshing them together under really high pressures.

The resulting wonder material could be the strongest, stiffest super-thin material ever created.

Since they were first synthesized in 2014, diamond nanothreads are still in their infancy. After all, researchers discovered graphene, the most promising supermaterial to date, in 2004, but they still haven't figured out how to truly harness its potential for marketable products.

But if diamond nanothreads live up to their lab tests, their applications could include serving as the material to construct a space elevator. Their incredible strength and thinness could make them light enough to actually carry objects and passengers into outer space.

We just have to get them out of the lab, and into the sky.

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Sometimes when you open a brand-new bottle of wine, it can smell like rotten eggs.

This obviously ruins the entire drinking experience, since a wine's smell is such a big part of how it tastes.

But there is a weird, almost free trick to fix the smell, and keep you from having to throw out that bottle.

All you need is a penny.

I know it sounds weird, but stick with me here — there's a chemical reason why this works.

During the fermentation process, when yeast turn grapes into wine, sulfur can sometimes get turned into compounds called thiols that can make your wine smell terrible.

Winemakers often spray sulfur on vineyards so mildew doesn't grow on the grapes. Most of the time, they'll stop doing this a few weeks before the harvest so that excess sulfur doesn't make its way into the fermenting wine.

Some of the sulfur can also come from sulfites that winemakers add as a preservative (you've likely seen "contains sulfites" that's required for labeling in the US).

Our noses are so sensitive to hydrogen sulfide — the source of the rotten egg odor — that we can even smell concentrations as low as one part per billion.

So if your wine smells bad, author Jeff Potter suggests in his book, Cooking for Geeks, that you get a penny, wash it, and plop it in your glass. As you mix it around with a spoon, the copper from the penny will bond with the stinky thiol molecules, resulting in odorless, harmless copper sulfide crystals.

Remove the penny, and drink up! (Responsibly, of course.)

This trick, sadly, doesn't work on a bottle of wine that has gone bad from being left open for too long.

You can see the full explanation from the American Chemical Society here:

SEE ALSO: 3 science-backed food hacks for preparing the ideal dinner party

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