New England Patriots

Could kombucha really have caused Michael Floyd's failed alcohol test?

Published Jun. 30, 2017 6:28 p.m. ET

Sports Illustrated, Jon Tayler/Sports Illustrated via Extra Mustard

In the annals of unexpected athlete excuses, we have a new entry courtesy Vikings wide receiver Michael Floyd. Under house arrest as a result of a conviction on a February DUI charge, Floyd reportedly violated the terms of his imprisonment by failing three self-administered breathalyzer tests earlier this month. But he claims that the alcohol in his body was the result not of beer or liquor, but kombucha, the fermented tea drink that contains a small amount of alcohol.

According to Floyd, he drank "four or five" bottles of GT Synergy kombucha during a late-night movie-watching spree (who among us) at the house of teammate Kyle Rudolph and subsequently registered a blood-alcohol content of .055 when he took a breathalyzer test at 5:30 a.m. the next morning. Among the factors Floyd claims helped that happen: the fact that he hadn't eaten anything since noon that day, and that the kombucha was warm.

The Vikings are backing Floyd, telling the court that they serve kombucha on tap at their practice facilities and encourage their players to consume it. But does Floyd's story hold (fermented and flavored) water?

Let's start with the actual alcohol content of the kombucha he was drinking. Because it's a fermented drink (it's a tea that contains an appetizing combination of bacteria and yeast in it), there is a small amount of alcohol in kombucha—anywhere from 0.5 to 2 percent. (For comparison's sake, a Budweiser is 5 percent.) GT's Living Foods doesn't provide the alcohol content of its drinks on its website, but it's safe to assume that their drinks likely fall somewhere in that range.

Now it's time for some math. Let's assume that GT Synergy is 2 percent ABV. Floyd's BAC when he woke up was .055. At 225 pounds and having consumed the kombucha over the course of three and a half hours, he would have had to consume anywhere from 10 to 15 bottles in that span to hit that mark—a far cry from the four or five he says he drank.

But Floyd's case isn't that cut and dry. For starters, kombucha is supposed to be refrigerated, and leaving it out at even room temperature can have an effect on its alcohol content, as the drink will continue to ferment when warm; Floyd told the judge hearing the case that he left his kombucha out instead of putting it away. There's also the fact that the advertised alcohol content of kombucha may not be accurate. In 2010, Whole Foods was forced to pull various unpasteurized kombucha brews off its shelves after it was revealed that they were up to six times over the FDA limit of 0.5 percent for non-alcoholic beverages (though it's pretty much impossible for kombucha to pass the 3 percent mark, given that that would require a third stage of fermentation in which grains are added). And as any person who's been to college will tell you, drinking on an empty stomach is an easy way to end up way drunker than you ever imagined.

Add that all up, and Floyd may have an argument here—or at least, one that isn't completely implausible. That was the conclusion reached by Dr. Thomas L. Bennett, a forensic pathologist hired by Floyd to bolster his case. Floyd's BAC levels, Bennett wrote, "are achievable and consistent with ingesting kombucha, in the circumstances and time frames as ... described."

But whether a judge buys his story depends on how likely it is that Floyd essentially stayed up all night chugging kombucha that happened to be way above its stated limit, which is about as weird a way as you can spend the wee hours of the morning. And as someone who's already been busted for driving under the influence multiple times, Floyd should probably just stay away from any alcohol whatsoever at this point. (It's worth noting that GT does make a non-alcoholic kombucha.)

Science experiment aside, the Vikings are likely hoping the judge buys the kombucha defense. Prosectuor Caron Close is arguing that, as a result of the failed alcohol test, Floyd should have to serve the rest of his house arrest sentence in jail—something that would cost him training camp, preseason and an early chunk of the regular season. Maybe Minnesota should try to convince him to switch to smoothies.