Cultures Across Cultures


My name is Liana and I am on an eight month journey to study our relationship with microbes, and their relationships with each other. I am a 2021 recipient of the Watson Fellowship, which grants recent college graduates the ability to explore a project of their choosing around the world. I proposed my idea to sequence fermented foods, with an emphasis on yogurt. This project was born in May 2020, in the midst of the COVID-19 pandemic, circa sourdough-making stage, but my excitement about fermented foods started much earlier. My grandmother taught me how to make Persian-style yogurt, and one of my best friends shared her family's kombucha SCOBY with me in high school. From a food perspective, I love the extra zing that ferments add to a dish, and am fascinated by how different cuisines incorporate ferments into their diet. From a science perspective, each round of fermentation is a science experiment that I think can offer insight into evolution, community dynamics, and stability in the face of change. I know I have only barely scratched the surface of understanding the abundance of diversity in fermented foods, and I am excited to pursue this in the coming months.

During my Watson, I will meet with local producers of yogurt, cheese, miso, and more. I hope to hear the wonderful stories about starters that have deep value to the people who sustain them. I will seek out rare microbes in naturally fermented foods, but see tremendous value in commercialized starters as well. How is the same starter impacted by its environment? Are there differences in the final microbial community depending on the type of milk, humidity, and duration? I aim to take environmental samples from equipment to see how external microbes worm their way into seemingly stable starter cultures. When possible, I will acquire sequential samples from the same producer to see how the community shifts over time. In each country, I will extract DNA from local fermented food samples with the support of Qiagen and a host lab. At the end of my stay in a country, I will ship all frozen DNA samples to my partner professor, Prof. Nicholas Bokulich, at ETH Zurich. In July 2022, I will pull together my samples and perform 16S and ITS sequencing to identify microbial communities that reside within. I aim to create a family tree of all samples I collect, perhaps seeing that sheep milk yogurt from Greece and Ireland display striking differences, or store-bought miso from Iceland is not so different from traditional samples from Japan. I will analyze the data and gather my thoughts. At this point, I will draw conclusions about how ferments from around the world, with such unique stories and futures, can inform underlying biological principles about microbes.

I am incredibly grateful for this opportunity to learn about the world -- big and small. With the daily changing pandemic situation, I continue to revise, update, and re-plan my journey. I expect a fair share of ups and downs. During the next eight months, I hope to learn to adapt, keep calm, and remain thankful for the time I have to travel, meet people, and do some science I love. I will post updates here along the way. If you have any questions, comments, or are interested to chat more, please feel free to reach out. Thank you for reading, I am sending my positive thoughts to you and the microbes inside you.