A Hidden Part of the Thanksgiving Story Revealed for the First Time in Centuries.

During the holiday season, we often overlook the origins of the food on our Thanksgiving tables. Most of these dishes are built from ingredients native to the Americas: squash, beans, corn, cranberries, blueberries, pumpkin, turkey, and potatoes. These foods are more than sustenancethey reflect centuries of exchange between Indigenous American cultures and European colonizers.

While goods such as tomatoes transformed Italian cuisine and horses changed transportation in the Americas, invisible passengersmicrobestraveled across oceans as well. Bacteria and viruses like smallpox and typhus arrived with European ships, devastating Indigenous populations who had no immunity. At the time, Europeans had only the earliest inklings of germ theory, understanding little about the microbial dimension of this intercontinental exchange.

These microorganisms also shaped culinary practices, particularly in fermentation. Centuries before scientists formally studied microbes, the Columbian Exchange had already altered the taste of beers, ciders, wines, and spirits. Yeasts, single-celled fungi that produce alcohol, have a profound influence on flavor. Today, scientists cultivate specific yeast strains for consistent industrial production, but historically, brewers relied on naturally occurring microbes and traditional methods.

Indigenous American fermentation practices were sophisticated long before European arrival. Drinks such as colonche (prickly pear cactus wine), tepache (fermented pineapple juice), pulque (fermented agave sap), and various corn beers thrived in pre-colonial North America, particularly in the deserts of the Southwest. Indigenous brewers used porous clay vessels and incorporated natural additives like grasses and lichens to guide fermentation.

Rox Tiburolobo, a Chiricahua Apache and Rarmuri brewer, highlights how traditional vessels fostered microbial communities. "With tesgino and batari, we traditionally add grasses and lichens that have antimicrobial effects similar to hops," he explains. This shows that Indigenous fermentation was a complex biotechnology embedded in culture.

European influence arrived in 1542 when the first official brewery in Mexico was established under King Charles V. Ships carrying beer and wine inadvertently transported yeasts and bacteria, introducing new microbial strains into the Americas. Modern microbiologists are now studying traditional fermented drinks to map the microbial species responsible for these processes.

Dr. Csar Ivn Ojeda Linares, an ethnomicrobiologist at the National Autonomous University of Mexico, has found some isolated Indigenous communities maintain native microbial strains free from European influence. For example, Coomcac, an indigenous group in Sonora, preserves traditional cactus wines without the common Saccharomyces yeast.

Research over the past century has revealed unique microbes in Indigenous American beverages. Early microbiologists like Paul Lindner studied pulque and discovered Zymomonas mobilis, a bacterium capable of producing alcohol more efficiently than yeast. Such findings underscore the global significance of microbial diversity in fermentation.

The exchange of microbes has permanently shaped brewing. Modern lager yeast, for instance, likely originated from a hybrid of European ale yeast and cold-tolerant South American strains. Indigenous knowledge of corn malting influenced early American whiskey production, highlighting the impact of microbial and cultural transfer.

As we celebrate Thanksgiving, its worth reflecting on this hidden dimension. The bounty of the table and the flavors of our drinks are products of centuries of microbial migration and human ingenuity. The microscopic travelers that crossed oceans alongside humans transformed our culinary landscape irrevocably, shaping the taste of beers, wines, and spirits around the world.

Commentary: The Hidden Microbial Legacy Behind Thanksgiving Foods

The Thanksgiving table is a celebration of cultural and agricultural exchange, with dishes that highlight ingredients native to the Americas. From turkey to cranberries, squash, and corn, these foods have long been staples in Indigenous American diets. However, behind these familiar ingredients lies a hidden story—one shaped by centuries of microbial exchange that continues to influence the flavors we cherish today.

While much of the focus during the holiday season is on the historical and cultural significance of the foods we eat, the microbial dimension of this exchange remains largely invisible. The Columbian Exchange, which brought European colonizers to the Americas, also facilitated the movement of microbes such as smallpox, typhus, and other bacteria. These invisible passengers wreaked havoc on Indigenous populations, who lacked immunity to such diseases. But alongside the pathogens, a different type of exchange took place: one involving the yeasts, bacteria, and other microorganisms that would forever change the landscape of global cuisine.

Before European influence, Indigenous American cultures had already developed sophisticated fermentation practices. Beverages like pulque, tepache, and colonche were crafted using natural microbial processes that shaped their distinct flavors. The introduction of European brewing techniques, coupled with the arrival of new microbial strains, further complicated the already rich microbial ecosystem. Over time, this blending of Indigenous knowledge with European methods would create the foundation for the modern brewing industry.

Today, as we raise our glasses to toast Thanksgiving, it's important to remember that the flavors we enjoy are the result of a long history of microbial migration and cultural exchange. From the fermentation of beverages to the production of whiskey and beer, microbes have left an indelible mark on our culinary traditions. This Thanksgiving, let's not only give thanks for the food on our tables but also for the invisible, yet ever-present, microorganisms that continue to shape our tastes and cultures.

Sources:

• There’s a Wild Part of the Thanksgiving Story That’s Been Invisible to Us for Centuries. Until Now.