MOLD’s series on Nightlife explores the rhythms, metabolisms and revelations that flourish best in the dark.

Growing up, mealtime was always an opportunity to practice the art of negotiation. “Eat your vegetables,” my mother would insist. “Hai dai is a vegetable,” I would counter. Whether or not seaweed, a macroalgae, fell in the vegetable category for my mother is up for debate, but in my adolescent mind, the taste of that briny knot of cellulose was far superior to any land vegetable on the table. With this familial association, the more recent rise of algae as a potential future superfood is confusing to me. In the United States’ consumer packaged goods market, most algae comes in the micro variety. Microalgae like spirulina and chlorella delivered as relatively innocuous powder in “functional foods” like shakes or bars sidesteps what I understood to be its draw—that algae tastes delicious. Launching this month, a new research project is leveraging heterotrophic (in the absence of light) techniques for urban cultivation, and celebrating the flavors of algae as a resilient, sustainable and cost-effective protein for cities in the future.

Indigenous people—including the Aztecs and the Kanembu of Central Africa—have incorporated the unctuous flavor of algaes for centuries. My own Chinese family uses various types of seaweed in soups and braises with similarities across gastronomies in Asia and the Pacific Islands. Although seaweed is a pantry ingredient in many Asian homes, the potential of microalgaes like spirulina and chlorella are not widely understood as a culinary ingredient.

In 2019, Singapore, an island city-state with a population of 5.6 million people, announced its ambition to produce 30% of its nutritional needs by 2030. The “30 by 30” project aims to build the foundations of food sovereignty in a highly urban setting faced with land and resource constraints. Understanding this, Singapore is an ideal city to explore the future of microalgae. The city has preexisting manufacturing infrastructure for food staples like tofu and beer, the waste streams from which organic nutrients could be captured and used for cultivating microalgae. Additionally, Singapore’s diverse culinary landscape is a fertile testing ground for how the flavor of microalgaes might present as a seafood or meat alternative. 

In the following  interview, we speak with Dr. Alexander Mathys, head of the sustainable food processing laboratory at ETH Zurich and Dr. Iris Haberkorn, the Singapore-based project lead, about the “Urban Microalgae-based Protein” project and its potential to transform how cities of the future might feed themselves.


What do you hope to accomplish with the Urban Microalgae Protein project and how does it address challenges around supply chain and cultivation? 

Alexander Mathys and Iris Haberkorn:

Our project focuses on process and supply-chain optimization along the whole value-chain:

1) Optimize food production by decreasing costs of microalgae production and establish circular economy concepts:

  • We will substitute components typically used in industrial microalgae cultivation media by nutrients found in food industry side-streams. Capturing these otherwise lost nutrients will allow us to decrease costs for microalgae production and improve supply-chain sustainability.
  • We aim for process and supply-chain innovation by building up a biorefinery concept using a novel technology: pulsed electric field (PEF) processing. The technology allows us to improve productivity and harvest components from the microalgae, e.g., protein, that we are interested in for food concept development.

2) Optimize food processing

  • We aim to develop microalgae-based food concepts with taste and nutrition profiles that meet consumer preferences. Therefore, our project will conduct consumer studies to obtain in-depth insights into consumer preferences and expectations related to microalgae-based products. This knowledge will be used to optimize processes associated with food production to create products that are tailored to consumer needs.


Algae is typically thought of as a photosynthetic organism – how does producing algae in heterotrophic conditions change both the inputs for production? Why is a heterotrophic condition important to this project? How might it affect the final product – specifically around questions of taste and texture?

AM and IH:

There are different reasons why we aim for using heterotrophic microalgae:

Consumer perception: Consumers prefer heterotrophic yellow biomass over green phototrophic alternatives owing to e.g. color difference. [Editor’s note: In a previous study, Mathys found that the green color of microalgae limit its application in other products like pastas and crackers, and adversely affects consumer perceptions about taste and quality]

Eco-efficiency: reduced energy requirements, as heterotrophic microalgae assimilate organic carbon in the dark, reducing the energy required for culture illumination. Furthermore, heterotrophic cultivation reaches much higher final concentration before harvesting (as there is no limitation like light penetration as in phototrophic cultivations)

Environmental sustainability: Heterotrophic cultivation of Chlorella species on food waste creates one of the most sustainable sources of protein.

Overcoming arable land constraints: Heterotrophic microalgae cultivation avoids competition for well-lit open spaces or rooftops in Singapore.


Working with the Food Science and Technology department at National University of Singapore (NUS), the project will also pilot a few food concepts. What facets of these food concepts are you most excited about exploring? 

AM and IH:

We are excited about any aspect of working together with our partners at NUS on this great new project.

These aspects include

  • The establishment of an R&D platform for food concept development, including large-scale industrial extrusion and small-scale decentralized 3D printing to create microalgae-based seafood analogues.
  • Optimizing food production and final products to what consumer really want. The project will deliver in-depth insights into consumer preferences and expectations. To date there is a limited number of studies indicating what consumers expect from microalgae-based products. These insights will allow us to tailor microalgae-based food production to consumer needs and create viable microalgae-based products.