Four Loko — the controversial caffeinated alcoholic beverage — will no longer be made with caffeine, taurine and gaurana, announced its makers, Phusion Projects, two weeks ago. Before the caffeinated “black out in a can” gets pulled completely from shelves, the Science Section presents: The Science Behind Four Loko (the caffeinated version).

THE FORMULATION

Phusion Projects have not released an exact recipe for Four Loko denoting the amount of caffeine in the drink. Their website states that one can of Four Loko contains as much caffeine as “a tall Starbucks coffee.” According to Starbucks, a tall drip coffee (12 ounces) contains a whopping, 260 milligrams of caffeine.  Red Bull, by comparison, contains 80 milligrams per eight ounce can.

This means that, a can of Four Loko contains up to three times as much caffeine as a cocktail made with Red Bull.

With 12 percent alchohol, Four Loko is a malt beverage. “Malt beverages” contain alcohol made during fermentation of grains, like barley, rather than concentrated alcohol added from distillation spirits, like vodka. Adding sugar to a malt fermentation can bump the alcohol content above the usual 5 percent alcohol content of beer, also a malt beverage.

The sugar content of Four Loko is neither listed on the  product label nor the Phusion Projects website.  Anecdotal reports suggest that the sugar content is high. The intense sweetness of Four Loko helps disguise the bitterness of its high alcohol content.

Prof. Harry Lawless, food science, studies the perception of food tastes and flavors. According to Lawless, flavor masking occurs between the four basic tastes at medium intensities.  The phenomenon – called mixture suppression – can occur between sweet and bitter flavors. Along the neural path to the brain, the signals cross, and the perceived intensities of the flavors decrease.

“On average, you get about a 30 percent reduction, and its mutual — sweet covers up bitter and bitter covers up sweet,” explained Lawless.  “So a spoonful of sugar helps the medicine go down, not just because it’s adding a pleasant taste, but because of this masking effect.”

Guarana and taurine — exotic-sounding compounds frequently added to energy drinks — are also on the to-be-nixed list for Four Loko. The Amazonian guarana fruit contains about twice as much caffeine and other related stimulants as a comparable amount of coffee beans.

Taurine is a naturally occurring acid found in seafood and meat; it was originally discovered in ox bile. The chemical is necessary for skeletal functioning in mice, but is commonly mistaken as an “upper.” Despite claims of medicinal purposes, a 2003 review of energy drinks concluded that the average amount of guarana and taurine in energy drinks was too low to have any pharmaceutical effects.

THE CULPRIT: THE ADVERSE EFFECTS OF CAFFEINE AND ALCOHOL

In warning letters sent to four producers of caffeinated alcoholic beverages, the U.S. Food and Drug Administration (FDA) called caffeine an “unsafe additive” when added to malt liquor. According to the letters, a scientific review of existing studies and expert consultation led them to the decision that caffeine in alcoholic beverages is no longer “recognized as safe.”  The FDA cited three reasons for their decision: the beverages produce unsafe behaviors, they reduce perception of intoxication, and due to caffeine, they promote a higher likelihood for intoxication.

The scientific research on caffeinated alcoholic beverages has focused on college-aged drinkers, one third of whom consume energy drinks regularly, according to Mintel data. The FDA warning letters cited one study, conducted by a team at the University of Florida in Gainesville, in which researchers interviewed over 1,200 patrons leaving bars in a college district about their intention to drive and measured their blood alcohol levels (BAC). The team found that participants, who had consumed alcohol mixed with energy drinks, were over three times more likely to have a higher BAC and were over four times as likely to intend to drive home compared to bar goers that drank alcohol alone. 

In another study from Brazil cited in the letters, male participants aged 21- to 26-years-old were given either alcohol and energy drinks alone or mixed. Those who consumed caffeine and alcohol were less able to sense the physical effects of intoxication — the headaches, weakness, impaired motor coordination and dry mouth of a heavy buzz — but still showed the same motor and visual coordination impairments expected from intoxication.

The research cited by the FDA concluded that caffeinated alcohol drinks make those who consume it drunker — and less aware of it — then those consuming alcohol alone. They also are more likely to take risks, like driving while intoxicated or being taken advantage of, sexually.

For now, the commercial life of alcoholic energy drinks might be over, but mixing caffeine and alcohol is likely to survive these drinks. After all, long before there was Four Loko, Lawless added, “there was Irish coffee.”