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Peaberry and maragogype: coffee bean anomalies and their flavour

Most coffee beans have a familiar, oval shape with a flat side - it is the effect of usually two beans developing in the coffee cherry, adjoining each other with their flat sides. But nature likes exceptions. Sometimes only one, round bean develops in the cherry - that is peaberry. Another time a giant bean appears, almost twice as large as a normal one - that is maragogype, called the elephant bean. These anomalies have long fascinated coffee lovers and are sometimes sold as something special. But do they really taste different? In this post you will get to know both bean anomalies, learn how they form, whether they have an influence on flavour and whether they are worth paying extra for. It is a journey into the biology of the coffee bean. Let us start with how a coffee bean normally grows.

How a coffee bean normally grows

To understand the anomalies, one must first get to know the norm. The fruit of the coffee plant, called a cherry, usually contains two seeds, that is coffee beans. These two beans develop beside each other, adjoining with their flat sides, and from the outside are rounded. That is why a typical coffee bean has a characteristic shape: one flat side (where it touched the other bean) and one convex, with a characteristic furrow in the middle of the flat side. Such a two-bean arrangement is the standard by which the vast majority of coffee in the world grows. Understanding this norm is the key to appreciating the anomalies: peaberry and maragogype are deviations from this scheme. The first concerns the number of beans in the cherry, the second their size. Both are natural and occur spontaneously. Nature, although it aims for a scheme, regularly creates deviations. So let us get to know the first of them, the best-known anomaly - peaberry.

Peaberry - a round bean

Peaberry, also called in Spanish caracol (snail), forms when only one bean develops in the coffee cherry, instead of the typical two. Without a neighbour to which it would have to adjoin with its flat side, this single bean develops evenly and takes a round, oval shape, contrasting with the typical flat-sided bean. It is a natural anomaly: a genetic or environmental irregularity causes the cherry to have only one seed. The formation of peaberry is attributed to various factors - weather, pollination or the way of cultivation. Peaberry occurs in a small percentage of each harvest, usually around a few percent. Because it has a different shape and size than the rest of the beans, it can be separated by sorting and sold separately. This makes peaberry rarer and often more expensive. The round peaberry bean has become a subject of fascination and marketing. But does this different shape also mean a different flavour? This question raises considerable discussion, to which we will return.

Where peaberry comes from

Peaberry forms when the process of pollination or development of the cherry proceeds atypically and only one of the two seeds develops. The exact causes are not fully known, but they are attributed to a combination of factors: weather conditions, imperfect pollination and the way of cultivation and the condition of the plant. Sometimes peaberry appears more often at the ends of branches or in particular conditions. It is a natural phenomenon that occurs in all coffee varieties in a small percentage of the harvest. It is important that peaberry is not a separate coffee variety or species - it is an anomaly that can occur in any coffee. Therefore peaberry from Tanzania or Kenya is simply the same varieties, only selected round beans. Understanding that peaberry is a condition, and not a variety, is key to assessing whether it is worth paying extra for. It is a developmental anomaly, not a genetic trait of a particular coffee. Let us now get to know the second great bean anomaly - maragogype.

Maragogype - the elephant bean

Maragogype, also known as the elephant bean, is an anomaly of a completely different kind: it concerns not the number, but the size of the bean. It is a variety of arabica that produces exceptionally large, rather porous beans - far larger than typical. Maragogype is a mutation that spontaneously appeared in Brazil, near a town of that name. Unlike peaberry, maragogype is a hereditary variety: maragogype bushes consistently give giant beans. These beans, impressive in size, have long aroused curiosity and are sometimes valued as a curiosity. Maragogype generally adopts the flavour traits of the soil and place to which it has been transplanted, which makes its profile variable and dependent on terroir. It is a variety of low yield, which together with the size of the bean makes it rarer and more expensive. Maragogype is proof that nature can create spectacular deviations from the norm. The elephant bean is one of the most recognisable curiosities in the world of coffee. But like any anomaly, it raises the question of flavour.

Do they really taste different

The most important question is: do peaberry and maragogype really taste different? Here the discussions begin. In the case of peaberry many professionals believe that because it grows as a single bean, it absorbs the nutrients from the cherry differently, which can lead to a more concentrated and vibrant flavour. Peaberry is sometimes described as more buoyant, more brightly acidy and more complex in the upper aromatic ranges, although somewhat lighter in body than comparable normal beans. However, others claim that peaberry does not change the flavour in the cup, and the differences are debated and overrated. In the case of maragogype the profile depends mainly on terroir, and the large, porous bean is sometimes associated with a mild, smooth flavour. The truth is that the evidence is ambiguous, and much depends on the particular coffee. The flavour of anomalies is a contested area between fascination and scepticism. It is worth approaching it with an open mind, but also healthy distance. We write more about how the quality of the bean is assessed in our post on grading green coffee.

The practical influence on roasting

There is one area in which bean anomalies have an undeniable, practical influence - roasting. The shape and size of the bean affect how it roasts, which is why the uniformity of a lot matters. Peaberry, thanks to its round shape, roasts more evenly than flat beans and is sometimes valued by roasters precisely for this trait: round beans turn in the drum and heat more evenly. This can be a real advantage, independent of the discussion about flavour. Maragogype in turn, because of its large size and porosity, requires a different approach to roasting than smaller, denser beans - a larger bean needs an adjusted profile to roast evenly inside and out. That is why maragogype is sometimes a challenge for the roaster. The practical influence of anomalies on roasting is thus real and measurable, unlike the debated influence on flavour. For the roaster the shape and size of the bean are concrete variables to take into account. It is another reason why anomalies are sorted and roasted separately.

Are they worth paying extra for

Since the differences in flavour are debated, are peaberry and maragogype worth paying extra for? The answer depends on what we are looking for. First, if we count on a flavour revolution, we may be disappointed - the evidence for a clearly better flavour is ambiguous. Second, however, it is worth remembering the real advantages: peaberry roasts more evenly, and both anomalies are interesting, rare coffees worth trying for the experience itself. Third, part of the premium results from rarity and the work of sorting, and not from guaranteed higher quality. Fourth, it is best to treat them as a curiosity and an opportunity for your own tasting, and not a certainty of better flavour. It is worth buying peaberry or maragogype to compare them yourself with normal coffee from the same source and form your own opinion. It is the best way to assess whether the premium makes sense for us. Bean anomalies are a fascinating topic to explore, but it is best to approach it with curiosity, not blind faith in marketing.

Bean anomalies in a table

Let us set both coffee bean anomalies side by side:

The table shows that peaberry and maragogype are two completely different anomalies. Peaberry is a developmental anomaly concerning the number of beans (one instead of two), occurring in any coffee. Maragogype is a hereditary variety giving giant beans. In both cases the influence on flavour is debated and dependent on the particular coffee, but both have a real influence on roasting. It is proof that nature creates fascinating deviations, and the coffee world likes to celebrate them.

The key points in a nutshell

Peaberry and maragogype are two natural anomalies of the coffee bean. Peaberry forms when only one, round bean develops in the cherry instead of the typical two flat-sided ones - it is a developmental anomaly occurring in a small percentage of each harvest, not a separate variety. Maragogype, the elephant bean, is a hereditary mutation of arabica giving exceptionally large, porous beans, whose flavour depends mainly on terroir. The influence of both on the flavour in the cup is debated and overrated, but they have a real influence on roasting: peaberry roasts more evenly, and maragogype requires an adjusted profile. It is worth trying them as a curiosity and comparing yourself. Want to compare different coffees and record your impressions? Keep tasting notes in the GustoNote app. See also our posts on grading green coffee and on arabica varieties.