In the culinary experience "Mundo en Desnivel" at Central, one of the courses is called Cacao Chuncho. This course highlights the specificities of the Chuncho variety of Theobroma cacao L. cultivated in the province of La Convención, in the jungle of the Cusco region. While when we hear "cacao," we usually think of "chocolate," the Cacao Chuncho course showcases the range of flavors and textures offered by the different parts of the fruit. In reality, only the interior of the cacao seeds is used for chocolate production, approximately 9% of the total weight of the fruit. The cacao production cycle generates many other usable inputs, both in harvesting and roasting, that are often not utilized.

Within the framework of the Theobromas Project of Mater — where different species of Theobromas such as cacao, macambo, and copoazú are researched — I was commissioned to explore Theobroma cacao L. from its material possibilities. In the current context of industrial and product design, we designers have an increasing interest in developing utilitarian objects from the responsibility of materials and manufacturing processes, and not just for the functionality and comfort of users. The Mater methodology, which starts from the research of species, processes, and local contexts for the formulation of applications and approaches in alignment with the territory, creates an opportunity. The materiality of objects can come from the same diversity and production cycles as food.

Cacao harvest in La Convención, Cusco. The pod is split open to obtain the cacao seeds, still wrapped in mucilage. Photograph by Camila Novoa

The Biomaterials project with Theobroma cacao L. was developed by an industrial design team made up of Maria Paula Loveday and myself, fueled by a constant dialogue with the Mater team. Through conversations with Ariadna Oliveri, culinary scientist at Mater, and Nilver Melgarejo, specialist in the Theobromas Project, we learned that during the harvest stage, significant volumes of cacao pods are generated that remain in the field and are discarded since the main input for making chocolate are the beans inside. These pods can become harmful to the environment and soils because they create suitable ecosystems for the proliferation of pathogenic microorganisms and mosquitoes. In certain seasons of the year, the leaves of the cacao tree are another input found in the field. After the fermentation and roasting of the cacao beans (or seeds), the husks are also separated, and while they can be used to make infusions, the post-infusion husks are also matter that tends to be discarded.

Considering these waste products as potentialities, the main objectives of the project were 1) to develop material samples to understand the specificities of each input from Theobroma cacao L. (husk, pod, leaf) and 2) based on these specificities, to propose applications for future objects, both in the context of the experiences at Central, Kjolle and MIL, as well as in other scenarios in the value chain.

The biomaterial diversity of cacao

During this exploration, the question arose several times: What defines whether a material is or is not a biomaterial? If we aim for circular design, a biomaterial is composed entirely of ingredients that, at the end of the object's life, can decompose without harming the environment, being biodegradable or even compostable. Unlike recycled plastics or composite materials with synthetic ingredients, a biomaterial can return to the earth. In this line, all the ingredients used in the project were selected for the subsequent biodegradability of the material samples and eventual objects we could propose from them.

Cacao husk in biofilm derived from algae, prior to drying

The preparation of the biomaterials involved the formulation of recipes and trial-and-error adjustments. In an infrastructure similar to a kitchen, we combined cacao inputs with different binders, using water as a solvent and, in some cases, additive ingredients to modify color and texture. Given the available quantities for each input, we made most of the samples with husk and then with pod, and used cacao leaves to perform a couple of specific tests. The diversity we developed reflects both the particularities of cacao inputs and the handling of proportions and drying times.

Another important variable in the material exploration was the development location of the project: the district of Barranco, Lima, where Casa Túpac and the Mater offices are located. In this seaside location, with high ambient humidity, placing the samples outdoors was in itself a test that helped us validate processes and opt for certain material formats. The results varied in tone, hardness, flexibility, water resistance, among others; and these variables could change in the samples from one week to the next. Beyond pragmatic requirements, designing materials and objects for specific geographic contexts carries value in itself, where the materiality of the object is closely linked to the place.

Samples based on cacao pod and husk with various binders

While we directed the project toward the search for practical applications, the samples began to build a palette of shades and textures. We began to notice differences between those made with pod and those made with husk. The cacao pod provides a grainy and uniform texture similar to ceramic with chamotte, and lighter, warmer brown tones. On the other hand, samples made with husk maintain a deeper dark brown color, leaning towards reddish tones. The husk fragments, all of different sizes, create patterns and contrasts like those seen in terrazzo floors. If these fragments are kept as whole as possible, the material makes the shapes and sizes of the cacao seeds it contains visible.

The smell was another factor that was present during the exploration, adding to the multi-sensory qualities of the cacao biomaterials. The husk, enveloping the seeds, has an intense chocolate aroma. For this reason, during experimentation, especially during the drying of pieces with husk, the Mater offices smelled like chocolate. Even eight months later, the first samples we stored in sealed containers have retained this characteristic. Meanwhile, the materials made with cacao pod initially had a fruitier scent but less intense than that of the husk. If at any point during the experimentation we had samples difficult to distinguish by color, the smell helped us determine the original input. The experimentation and progressive accumulation of all the produced samples have helped establish a library of materialities that reflect the particularities of cacao inputs.

Conceptualization and applications

Since, as mentioned earlier, biomaterials are by definition biodegradable, the lifecycle becomes prominent in the design of new objects. In this line, it becomes important to formulate materials with a lifespan in line with the imagined applications and, likewise, to imagine applications in accordance with the scopes and possibilities of these new materials. In an initial stage, the exploration was divided into two main material formats. On one hand, the solid format refers to the samples that originate from a pasta development that, through drying, harden and form volumes, slabs, or non-flexible filaments. Another key format was the thin and flexible laminar materials.

Flexible sheet made with crushed cacao leaves

The orientation of applications was developed thanks to the exchange and dialogue with Virgilio and Malena Martínez. Based on the requirements of the culinary experience at Central, there is an interest in developing tableware to present the courses related to cacao, such as Cacao Chuncho. In this framework, after jointly reviewing the initial tests, Virgilio asked us to investigate the development of trays based on the husk samples, as well as three-dimensional structures that could serve as presenters for cacao bars. Then, for the new iterations, we took into account requirements for the restaurant context: ease of cleaning, resistance to contact with water, weight-bearing capacity.

Whole cacao husk tray and powdered husk bowl

Powdered cacao husk bowl, constructed by extrusion

In the case of the cacao husk tray, we created plates with increasingly larger dimensions to progressively validate our formulations. We molded the biomaterials in their wet state and, during drying, the initial shapes of the objects changed. While the distortions or cracks in the dried objects could be perceived as flaws, we considered that these transformations could be integrated into a potential production in which each piece would be slightly different. For the construction of three-dimensional structures, we opted to create pastes with crushed inputs (husk or pod), in order to generate filaments or threads with the help of a syringe for extrusion. Depositing the material with the help of a syringe allowed us to direct the filament to create two-dimensional drawings or, with the support of molds and matrices, generate light volumes.

Samples of cacao husk constructed by filament deposition (extrusion)

The development of samples led us to imagine different usage scenarios for cacao biomaterials, both for the short term and in small batches, as well as for the long term, considering greater development times and scalability. Taking into account the volumes of cacao inputs, it was also important for Mater to map applications outside the restaurant context. In parallel to the objects of interest for the Central experience, together with Malena we validated and proposed routes for applications that could have an impact in other scenarios.

Steps forward 

This first stage of the Biomaterials project with Theobroma cacao L. has served to define the potentialities of developing new materialities from the value chains surrounding food. The results of this project are a first batch of samples and prototypes that validate concepts for new objects to be developed in greater depth. Eight months after having created the samples, we have been able to make a first selection based on their behavior both outside and inside storage conditions. These observations have helped clarify the viability of cacao biomaterials and guide the production of larger pieces. An example of these advancements is the series of bowls we later designed for Hilos de Tiempo, the Mater exhibition that took place at the Museo Pedro de Osma, just a few blocks from Casa Túpac. The project has also been a starting point for the subsequent creation of the Research and Application Department in Materials of Mater (I+A Materials), which seeks to link gastronomic contexts with industrial design for the creation of new objects and materialities in close dialogue with the territory.

Cacao husk as input (left) and as object (right)

Team

Design, development, and execution: 
Paula Cermeño, product designer, director I+A Materials Mater
Maria Paula Loveday, assistant in industrial design

Dialogue and advice from Mater: 
Ariadna Oliveri, culinary scientist 
Nilver Melgarejo, specialist in Theobromas Project
Patricia Yraja, project director 

Leadership of Mater: 
Malena Martínez
Virgilio Martínez