The Theory of Lupulin Threshold Shift

What is Lupulin Threshold Shift, does it change your palate preferences, and can the phenomenon be reversed?

In 2005, legendary Russian River brewer and proprietor of a face that does not age, Vinnie Cilurzo, coined the term “Lupulin Threshold Shift” (LTS). The term describes how a person’s exposure to hoppy beers increases their tolerance of bitter flavors over time – increasing the threshold of what they find too bitter to enjoy. This in turn changes their perceptions and expectations of beers they may have previously revered.

Interestingly, Cilurzo presented the concept many years prior to keyboard heroes declaring that, “Pliny is overrated.” Was this premonition a fortunate happenstance or a pre-emptive rebuttal to these remarks? We may never know. However, it was a time when double IPAs and other aggressively hoppy and bitter beers were far from the mainstream craft that they are today, so it was certainly a perceptive call.

Lupulin, of course, is the sticky yellow resin found in hop cones that contains both the acids and essential oils that are manipulated in the brewing process to infuse bitterness and hoppiness respectively into the finished beer (Hieronymous, 2012). Beer drinkers inflicted with this potentially devastating condition often discover the beers they once thought exceptional examples of hop-driven assertiveness appear pedestrian in comparison to bigger, bolder, hoppier beers that now seem more exciting.

For example, the progression of Lupulin Threshold Shift might look something like this. A beer connoisseur, who has enjoyed a fine example of a helles for many years, suddenly finds the beer lacking – they can now only garner the same level of satisfaction from a more hoppy pils. Soon enough, their threshold has shifted again, and they are drinking pale ales. The LTS continues, and IPAs are required to hold their interest. The IBUs and hop-driven characteristics in their beers of choice continue to build and they rapidly discover they have run out of options for beers that achieve a level of hop aggressiveness that piques their interest – nearly every beer has become insipid and their hedonistic beer-style spiral is complete.

In 2005, legendary Russian River brewer and proprietor of a face that does not age, Vinnie Cilurzo, coined the term “Lupulin Threshold Shift." The term describes how a person’s exposure to hoppy beers increases their tolerance of bitter flavors over time.

The LTS concept makes sense, particularly when parallels are drawn with spicy food. Most people do not pick up a West Coast American IPA for the first time and initially love it as the bitterness is too intense (though the aroma is often appealing). Similarly, most people cannot indulge in a Thai spicy curry as their first foray into spicy food. Essentially, these very bitter beers (and very spicy foods) need to be worked up to over a period of time with consistent exposure and increasing thresholds.

While the LTS has not been scientifically researched, the concept of spicy heat tolerance, a comparable notion, has been explored. For example, a 2012 study found that experience is the key factor for preference and tolerance of spicy food, as opposed to personality differences or physiological adaptation. This is the same with beer drinkers’ tolerances and thresholds of hops – experience and repeated exposure to hoppy beers leads to greater tolerance.

A broader study about how humans perceive smell (Keller and Vosshall, 2004) suggests that the impact of aroma (and, by extension, flavor) can change over time. This change occurs via adaptation, notably by increasing concentrations over time. While not exactly the same, the parallels with the concept and consequences of Lupulin Threshold Shift are striking.

Indeed, there is also plenty of anecdotal evidence to further support the concept. Googling “Lupulin Threshold Shift,” brings up a raft of posts from beer aficionados, lamenting the newfound insensitivity of their palates. It could be argued that the LTS is responsible for the consumer shift from pale ales to IPAs as the most popular style over the past decade. The misery experienced by beer drinkers when the LTS renders their former brews bland and unexciting is genuine.

Considering this tragic palate transformation, one question that many have posed is “can the phenomenon be reversed?” Sadly, no definitive answer can be given as no academic studies have been conducted on this important question. However, there have certainly been reports that Lupulin Threshold Shift can be put into reverse, including in my own experience.

What is to become of someone who can no longer handle absurdly hoppy beers? The first priority might be to return to beers that had once seemed extraordinary, but then shifted to pedestrian – chances are, they will be extraordinary again.

When I moved to Germany in early 2019, I knew I would not have access to the aggressively hopped craft beers that I had become accustomed to in the U.S. I accepted my new lifestyle and set forth, decisively worked my way around Germany, indulging in regional beer specialties including pils, rauchbier, alt, gose and bocks. I travelled the Czech Republic where I enjoyed pale, amber and dark lagers. I also had access to fresh Belgian beers, partaking in saisons, dubbels and gueuze.

These beers, while excellent, were not designed to push the limits of one’s lupulin threshold, particularly post-modern U.S.-style craft palates accustomed to high hopping rates. To be fair, Germany, the Czech Republic and Belgium do have some American-style craft beers; however, the traditional beer cultures of these countries remain strong enough that uber-hoppy styles are not yet mainstream and when available, they tend to be far more balanced and restrained than what we have come to expect in the U.S.

Fast-forward to 2020 and after a year in Europe, I’m back in the States. My first indulgence upon arriving was Cigar City Jai Alai IPA, a 7.5%, 70 IBU beer. It’s a benchmark IPA I have enjoyed before, albeit one that, by recent standards, does not push the boundaries of either bitterness or hoppiness.

Upon pouring the beer, without even needing to bring the beer close to my face, I was blown away by the multilayered citrus hop aromas. I excitedly took a sip and was instantly overcome by the bitterness. While the beer was delicious, my palate felt crushed by what I perceived to be “overwhelming bitterness.” A beer that would not have challenged my bitterness threshold a year prior had turned me into a whimpering mess.

I moved onto another beer that I have loved for many years – Sierra Nevada Bigfoot. Even though the beer is 90 IBUs, I thought the extra alcohol (9.6% ABV) of an American Barleywine and caramelized malts would offer a lower perceived bitterness than the Jai Alai. Wrong again! Not only was I overwhelmed by the bitterness and assertive hoppiness, but even the alcohol and caramel hit me in the face like a jackhammer.

These beers I had enjoyed for years were defeating me. The strong threshold I had built over the years of hammering my palate with hops had greatly diminished. A year away from heavy hopping and aggressive bittering had caused me to experience Lupulin Threshold Shift.

What is to become of someone who can no longer handle absurdly hoppy beers? Well, the first priority might be to return to beers that had once seemed extraordinary, but then shifted to pedestrian – chances are, they will be extraordinary again. In the past, these new-age, insensitive palates would have had to drink a double IPA to get their lupulin high; with a lower lupulin threshold, a standard American pale ale will more than suffice. Hugely roasty, tannic Russian imperial stouts can be traded in for porters. Finding subtle hop esters in lightly flavored beers like helles or kölsch might become the new norm. Whereas once a lack of intensity would have reduced a beer’s impact, the lower threshold individual might very well find themselves awarding points for subtlety.

Indeed, Lupulin Threshold Shift is a phenomenon that begs more investigation not just in terms of increasing sensitivity to hop bitterness, flavor and aroma but also for the reverse. In fact, this understanding may lead many to re-evaluate what constitutes a refined palate or indeed what great beers are.