Hoses and noses

Publicans, restaurateurs, bartenders and anyone else who serves beer and other beverages on tap has a great deal of power in their hands. Just a few yards of hose determine whether a beer comes out tasting and smelling fresh and highly drinkable or whether it is tainted by dispensing line microbiota and thus decidedly undesirable from the standpoint of customers’ noses. And, as the Spider-Man comics we Gen X kids read in the 70s taught us: “With great power comes great responsibility.” Moreover, functional beverages present new challenges, some of which are rapidly evolving as we speak in North America.

For those living in a European country that may have had laws mandating regular line cleaning, you might have been disappointed to see it repealed, as the Getränkeschankanlagenverordnung (beverage dispensing system regulation) was in Germany in 2005. Now, these countries are dependent upon more general regulations governed by European food hygiene and safety laws, which do not mandate regular line cleaning, though it is recommended that beverage lines are cleaned every seven days. Non-EU countries may or may not have regulations concerning line cleaning or may not enforce them.

The responsibility for cleaning draft lines is one that some are willing to shoulder while others shirk it without compunction or do so merely out of ignorance. How frequently and how well one performs a cleaning cycle is a very sticky subject between those tasked with servicing the draft lines and the breweries producing the beer being dispensed through them. Beer tainted by dispensing line microbiota usually reflects poorly upon the brewery and not upon those pouring it. Anyone with a nose and who is familiar with the whiff of these microbiota can usually tell how frequently and how well the lines are cleaned. Of course, the beverage itself determines its susceptibility to contamination, which we discussed previously at the Magpie & Marten (cf. ‘The laws of nature and non-alcoholic beers’).

Generally, draft line microbiota find beverages at higher temperatures, with a more moderate pH (> 4.5), fewer hop bitter substances, less attenuation (more carbohydrates), less ethanol and higher levels of free amino nitrogen more appealing. These include aerotolerant gram-positive lactic acid bacteria (Lactobacillus, Pediococcus), microaerophilic or aerobic gram-negative bacteria (e.g., Acetobacter, Gluconobacter) as well as yeasts, among them facultative aerobes, like Saccharomyces, and aerobic and respirative genera, such as Brettanomyces and Candida, among others.

In the authors’ experience, there are restaurateurs and bartenders who have never cleaned their lines; for instance, at wine or cocktail bars that also serve draft beer. When further questions are posed, the publican might respond: “Well, no one’s complained yet.” When asked, “So, do you sell much draft beer?” The response is usually, “No. Not really.” And for good reason.

Beer might taste bad coming out of dirty lines; however, the only thing it can permanently harm is a brewery’s or a bar’s reputation, given the lack of pathogens in draft line biofilms. Still, the absence of regulation can be disappointing to customers looking forward to a highly drinkable beer. This problem is as old as draft beer itself, but there are new issues confronting those serving beverages on the cutting edge.

High noon in the Wild West

Like board games and Zoom, ready-to-drink beverages (RTDs), such as canned cocktails, like a Manhattan or Negroni, and long drinks, which include Long Island iced tea, gin fizz or the highly popular espresso martini, have been on the rise since the Covid pandemic. Given their propensity for strong flavors and fruity essences, these beverages present a special challenge for those cleaning their lines if they want to avoid tainting any of the more delicately nuanced beverages served afterward.

Functional beverages infused with adaptogens, nootropics, pre- and probiotics as well as cannabidiol (CBD) and tetrahydrocannabinol (THC) are also now being served on draft, primarily in North America. These beverages are touted as aids for relaxation, boosting energy levels or gut health, or for improving mental clarity, among other things. All of them present technical challenges similar to those posed by non-alcoholic ‘beer’ (not really beer from this perspective), meaning that draft lines will have to be cleaned even more frequently and much more thoroughly than normal.

What these functional beverages do for those who enjoy them is not really clear and is routinely expressed in vague terms. For instance, adaptogens purportedly reduce stress and instill a general sense of well-being. Nootropics are not pharmacologically defined and are commonly known as ‘smart drugs,’ ‘brain supplements’ or ‘cognitive enhancers.’ They are supposed to increase the brain’s supply of glucose and oxygen, while also protecting its tissues from neurotoxicity, supporting neuronal protein and nucleic acid synthesis and even stimulating phospholipid metabolism – all thought-provoking points to ponder, perhaps even more rapidly and effectively with a nootropic-infused beverage. Speaking of regularly keeping lines clean, we move down to the so-called ‘second brain,’ where pre- and probiotics support the human microbiome, i.e., they keep our little symbiotic friends happy and thus foster good gut health.

A budding issue

None of these are as controversial as beverage infusions derived from hemp. Those containing THC are considered intoxicating beverages and are subject to all the precautions incumbent upon alcoholic beverages regarding the operation of motor vehicles, minors and pregnancy. The regulatory environment (or lack thereof) has suffered, in particular, due to the recent DOGE cuts in the US. Moreover, given that the US government now seems more willing to cater to the needs of wealthy corporations, regulators are left burning the candle at both ends, are spread too thinly across the food production landscape and are being tossed around on capricious seas by callous market forces (we’re mixing metaphors like some functional beverage producers blend their ingredients). This is one of the reasons that the recent upsurge in beverages containing CBD and THC has brought with it unforeseen complications in beverage dispensing systems. If a beverage contains THC and is served through draft lines, how much of it bleeds into the beverage lines is unknown. If another beverage is served through those same lines after cleaning – whether sufficient or not – does it still linger? Given its psychoactive properties even at low concentrations, this should be a serious concern for regulators.

“The safety of the people shall be the highest law” (Cicero)

NABs are prone to contamination – and by more obnoxious microbes – since they do not possess the safeguards inherent to conventional beer. A number of functional beverage producers are constantly experimenting with new ingredients with little thought about their interactions with the materials or microbiota in dispensing systems or their probable combined health effects. In this environment, hitherto unprecedented incidents will probably occur that cause producers and those dispensing their beverages to be burdened with new regulations – and in this case, they might even be enforced.

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