How Does a Breathalyzer Work?

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How does a breathalyzer work?

Adey Hill:

The breathalyzer or intoxilyzer is a modified IR spectrometer.

Before I get into that, let's talk about alcohol and how it gets into the blood and breath: Alcohol is a general name for a group of organic compounds. Ethanol, the alcohol we consume in alcoholic beverages, is a relatively small molecule. As such it is easily absorbed through the stomach into the blood. Alcohol is volatile and your body is warm. Each time you breathe, a small amount of the alcohol in your blood vaporizes and is passed into the alveoli in your lungs and passed out of your body. The more alcohol you have consumed, the greater the amount that passes out.

Organic compounds absorb infrared radiation (IR) at different wavelengths and have an IR signature. The infrared (IR) spectrometer in the intoxilyzers is calibrated so that it is at the wavelength that ethanol absorbs it.

When you blow into an intoxilyzer, the breath you expire passes into a sample chamber and if you have been drinking then so will some of the alcohol that has passed from your blood to your breath. In the case of the Lion Intoxilyzer 6000s produced by Lion Labs, the machine starts sampling the breath immediately as it starts to enter the chamber and does so 37 times per second. The machine continues to monitor this until you blow a consecutive reading for three seconds. This is so that it is taking the reading from the deep lung air, where the greatest concentration of alcohol is. Once this is achieved the machine will register that a satisfactory sample has been taken. It will then purge itself and move to the next stage (either a second sample or a calibration check).

The breath in the sample chamber is surveyed by a beam of infrared radiation (there is an IR detector behind the chamber). The machine knows the amount of IR that was fired at the chamber and the detector calculates how much has been absorbed. Some clever math works out how many micrograms of alcohol are present in 100 ml of breath. This reading is then displayed.

Some other factoids about the machines: breathalyzers can detect other substances such as methanol, isopropyl alcohol, or acetone. If these are present in sufficient quantities, the machine will register them as an interfering substance and your sample will not be deemed satisfactory.

The breath tube (which you blow into via a single use mouthpiece) is preheated to a specific temperature to ensure that the samples conform to Boyle's law and are consistent and accurate every time.

The machines can detect mouth alcohol. If you have recently consumed alcohol or used an alcohol-based mouthwash, the machine can detect it. The intoxilyzer starts sampling as you start to blow, so it will detect a high concentration of alcohol present at the start of the process, followed by a downward slope (on a graph); this spike tells the machine that there was more alcohol present at the beginning of the sampling process than at the end, and that this must be due to the presence of mouth alcohol.

You cannot cheat or defeat the intoxilyzers by trying to blow down the sides of the mouthpiece, putting your tongue over it, or putting some kind of catalyst (like a copper coin) in your mouth first. The only way to beat it is to not drink and drive!

This post originally appeared on Quora. Click here to view.

What's the Difference Between Tequila and Mezcal?

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iStock.com/mediaphotos

Aside from tacos, enchiladas, and other tasty tortilla-wrapped treats, tequila and mezcal are among some of Mexico’s best-known offerings in the food and beverage category. These tipples, made from the agave plant, are so embedded in the country’s culture that Mexico City even has a museum dedicated to the two drinks, and Jose Cuervo operates a "tequila train" to none other than the city of Tequila. These beverages can be used to make a variety of cocktails, from the tequila sunrise to the mezcalita, but unless you’re a bartender or a connoisseur of spirits, you might not know the difference between the two. Is mezcal just fancier tequila?

Not exactly. Tequila is a type of mezcal, but the reverse isn’t always true. It’s similar to the distinction between champagne and sparkling wine, in which the name of the beverage depends on whether it was produced in the Champagne region of France or elsewhere. While mezcal can be produced anywhere in Mexico, tequila is made in the Mexican state of Jalisco (though a few exceptions do apply).

Tequila and mezcal also differ in the ingredients from which they are derived. Mezcal can come from any of the dozens of agave plants—a type of desert succulent—that are grown throughout Mexico. Tequila is made specifically from blue agave and, depending on the variety and brand, a bottle will contain between 51 percent and 100 percent of the plant-based nectar. According to The Tierra Group, a wholesaler of agave products, blue agave nectar is especially sweet because it’s 80 percent fructose, per Mexico’s regulations.

Lastly, tequila and mezcal taste different because of the ways in which they are prepared. Mezcal tends to have a savory, smoky, earthy flavor because the agave hearts (or piñas) are left cooking for several days in a fire pit that has been lined with volcanic rock and covered with agave leaves and earth. The piñas destined to end up in tequila, on the other hand, are often cooked in a brick oven, then crushed up to extract the juice.

If you ever feel adventurous at the liquor store and decide to bring home a bottle of mezcal, just keep in mind that there’s a particular way to drink it. “The first mistake many people make is pouring mezcal in a shot glass and pouring it down their throat,” Chris Reyes, a mixologist at New York City’s Temerario bar and restaurant told Liquor.com. Instead, the spirit is best sipped in a clay cup known as a jicarita.

Some words of advice if you do go shopping for mezcal: If you ever see a worm at the bottom of the bottle, that means it’s probably not a very good mezcal, according to Reyes. By contrast, tequila bottles should never have worms in them (despite the common misconception). So if you’re looking to avoid invertebrate-infused concoctions at all costs, tequila is your best bet.

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All Aboard! Mexico Is Now Home to an All-You-Can-Drink Tequila Train

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iStock.com/Clicknique

If you like the idea of taking a booze cruise or imbibing while flying (on a craft beer flight, that is), then you may enjoy the hooch caboose. As Delish reports, the latest in luxury, alcohol-packed travel comes from Jose Cuervo, which is now operating an all-you-can-drink tequila train.

That’s right: You can now hop aboard the Jose Cuervo Express and slam shots or sip tequila sunrises while traveling in style from Guadalajara in western Mexico to—where else?—the city of Tequila. The deal includes round-trip train transportation and bottomless drinks at the open tequila bar, plus snacks. Guests will also get to join a separate tequila tasting with experts, take a tour of the Jose Cuervo distillery in Tequila (the oldest one in the Americas), and take in a Mexican cultural show.

The Jose Cuervo Express has been around a while, but the round-trip, all-you-can-drink tequila experience is new. Since 2012, the train has been operating regular “sunrise” and “sunset” hours, offering guests a morning train ride to Tequila with an evening bus ride back to Guadalajara, and vice versa.

Prices for the new experience start from $111 on the Travel Pirates website, but the cost depends on the exact package you choose. If tequila isn’t your cup of tea, you might prefer the Mayan train line that’s slated to connect some of Mexico’s most famous pyramids and sites. Those plans are still a work in progress, though.

[h/t Delish]

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