Our bodies are pretty miraculous and interesting machines. They have mechanisms to deal with nearly any situation that may present itself. Take our senses of taste and smell for instance. These senses steer us towards foods that will nourish our bodies and keep the machine running. They also provide powerful warnings to us when something may cause us harm if ingested. Taste and smell are triggers to many powerful memories and hard-wired instincts. It’s like our bodies have an automatic alert system to warn us away from foods and drinks that will harm or kill us. Oddly though, we can overcome those warnings and even develop an affinity to foods that go against our body’s natural instincts.
Bitterness, for example, is a flavor that many of us have grown to love. Yet, in the plant world, bitterness is used as a defense and often is a signal that the plant being eaten is poisonous. Further, our hard-wired proclivity is to dislike bitterness because most bitter substances are nutritionally useless. If you have ever seen a baby eat something bitter, you probably noticed the child’s face scrunch up into an expression of intense dislike. Humans are just not supposed to like things that are bitter.
And yet, beer aficionados wax philosophically about the intense hoppy flavor of their favorite beers. Indeed, it seems that we are in the midst of an all-out assault on our bitter-recognizing taste buds by brewers concocting beers such as Bell’s Hopslam and Dogfish Head 60 Minute IPA.
Why is it that, though our bodies and instincts say “no,” our appetites say “oh, hell yeah!”? The answer is quite complex and delves into a number of different disciplines.
Before we try to figure out this strange mystery we need to look at a few terms and concepts.
First we need to explore the idea that bitterness has a range of intensity much the same way as spiciness has a range of heat. In spiciness this is measured with the Scoville scale. The higher the number of Scoville units, a measure of the chemical capsaicin, the spicier a pepper is. In bitterness a measure called the International Bitterness Unit (IBU) is used to express the intensity of bitterness of a beer that is derived from hops. Just like with Scoville units, the higher the number the more intense the beer. Calculating a beer’s IBU is a complex and sometimes mystical process. It requires a lot of math and/or the use of a device called a spectrophotometer.
When a brewer sets out to make a specific kind of beer, he or she usually has a flavor profile in mind. Every beer style has a range of flavors including the amount of bitterness you should expect. For instance, a Belgian-style blond ale may have an IBU rating between 15 and 30. On the other hand, a double India Pale Ale may tip the IBU scale at 60 or more. In order to reach the target profile of the beer to be brewed, the brewer can use a rather complex mathematical equation that will approximate the ending IBU rating of the beer. The equation takes into account such factors as the weight of the hops used in ounces, the volume of the wort (unfermented beer) in gallons, the amount of time the hops stay in the wort as it boils, and the amount of alpha-acids that are present in the hops used. Easy, right? After the brewer carefully takes all the necessary measurements and brews the beer, solvent extraction and the spectrophotometer can be used to get a more accurate IBU rating.
As mentioned above, hops are what provide the bitterness in beer, but all hops are not created equally. Hops flowers contain alpha and beta resins and essential oils within the lupulin glands of the flower. Alpha resins are not very soluble in water; therefore, need to be boiled to extract the proper bittering from the alpha acid. Hop oils are very soluble in water and will boil off quickly with the steam of the boil. Different types of hops impart different flavors ranging from pleasant grapefruit to harsh pine. The trick is in combining the styles of hops and controlling the amount of time each type is boiled with the wort.
So, know we know that the higher the IBU rating of a beer the more intensely bitter it is, right? Well, not always. You see, malt is also an essential part of beer and malt provides sweetness. The more malt there is in a beer, the less intense a high IBU rating will taste. This is why stouts often have relatively high IBU ratings, yet do not taste all that bitter.
Contradiction seems to be a normal state when it comes to beer and bitterness and why we like it.
Back to bitterness and why we like it then. We know that bitterness is a warning marker for our body that usually means something is bad for us in some way. The chemicals responsible for the bitter taste are called alkaloids and are generally toxic. Plants produce them as a protective device to keep animals from eating them. Basically, we should run from bitter substances, but we don’t. And, to muddy the water further, in addition to toxicity, some alkaloids have medicinal and psychoactive properties. Caffeine is a stimulant, morphine and codeine are pain killers, and quinine is effective in fighting malaria. But, they are all bitter.
The reasons we enjoy our bitter beer are just as twisted and complex as the route we took to learn about bitterness. Some reasons are psychological, some are learned, and some may be physical. It’s as complex and ever-changing as the movement of leaves in a tree during a windstorm.
Psychologically we may seek out bitter beers as a way of proving to others that we are truly connoisseurs of beer. Our ability to endure greater and greater amounts of bitterness is used a badge of honor to display to the world that we are truly in the know and on the razor’s edge of the craft beer movement. And sometimes it is shear thrill-seeking, pushing ourselves to the limits for the pure endorphin rush of it.
Other theories of why we like bitterness hypothesize that we are fond of it for ritualistic, magical, or self-medicating reasons. Bitter substances lead to mild altered mental states. Bitterness is an integral part of many of the things we do every day. Many people can’t seem to function without their morning coffee, which contains caffeine a bitter substance. Nicotine in tobacco is bitter, but many people are compelled to smoke. And one of the most common flavors the world over is chocolate, a substance steeped in mysticism, and it contains theobromine, a very bitter alkaloid.
Physical cravings may also account for our desire for bitterness. Our bodies are programmed to seek carbohydrates or energy on which it can function. Highly hopped beers often have a higher content of sugar-releasing malts, which leads to a higher carbohydrate fix.
But, when you get right down to it, wonderfully hoppy – and therefore bitter – beer satisfies something that you just can’t put a finger on. It’s akin to the reason we strap ourselves on to roller coasters and trust teenaged operators with our lives. No matter how complex the reason, no matter how much we are predisposed to not ride the coaster, we get on it and scream our lungs out in terror. Then, when the rides over we laugh hysterically and get back in line to do it all over again. We drink hoppy, bitter beers for the thrill of it, to please our own palates and push our senses to the limit.