How we fed the last 100 billion humans won’t be how we feed the next trillion

By Nathaniel Chu and Josh Moser, Founders of Tezza.

Corresponding author: Nathaniel Chu, info@tezzafoods.com

Google Docs Version here

Summary

• Food is responsible for more carbon emissions than all fossil fuels burned to date because of the staggering footprint of converting the world’s forests into agricultural land

• Cows (beef, cheese) are the least efficient foods, particularly in terms of land use

• Tezza uses microbes instead of cows to transform efficient, nutritious, and inexpensive plants into fermented foods people crave and can afford

• We’re starting with 🧀

Introduction

Over the last 200,000 years, 100 billion people have lived and died on Earth [1]. And although only some of them got to play with fire, books, and e-bikes, every single one of them needed to eat.

Food is our first and most important industry. Most major early human inventions (tools, fire, language, writing, agriculture) served to get more food [2]. Our quest for ever-greater amounts of food reshaped the planet: we ate all the large animals [3] and turned half the world’s habitable land into farms [4]. What we eat is also a primary cause of climate change.

Food is responsible for more greenhouse gas emissions than all fossil fuels burned to date

In our current “holy crap” climate moment, we tend to focus on energy for machines: Greenhouse gases from burning fossil fuels are altering climate patterns [5]. To feed the energy needs of an industrializing world, we have over all of history released about 1.5 trillion tons of CO2 into the atmosphere from burning fossil fuels: 500 billion tons of CO2 from oil, 250 billion from natural gas, and 700 billion from coal [6].

But this focus misses the fact that food is energy for humans. Yes, burning fossil fuels releases greenhouse gases; what fewer people realize, however, is that agriculture—particularly land-use change—does the same. If we broaden our view of climate change to account for the footprint of food and agriculture, we find two surprises:

1. Carbon released from agriculture-driven land-use change (most of which occurred since the industrial revolution) outstrips all carbon released from fossil fuels to date

2. Reforestation of that land represents an equally huge opportunity for carbon sequestration

Although our use of fossil fuels is rightfully a focal point in the sustainability fight, it’s easy to forget that we used those fossil fuels in part to dramatically change the face of the planet. Those changes set us up for our climate crisis.

Today, agriculture directly contributes 17–34% of annual greenhouse gases (including methane from cow burps and ammonia production) [7]. But this present-day activity is dwarfed by the historical greenhouse gases released from converting half the world’s habitable land into fields.

When we convert a forest or grassland into farms or pasture, the carbon that was previously stored in those trees and soils is released into the atmosphere. Either the living matter is burned (slash-and-burn agriculture [8]), or it decomposes. Both processes release CO2.

Since the agricultural revolution, agricultural land-use changes have released 1.7 trillion tons of CO2 [9]. The vast majority of that land-use change came after the 1700s, as globalization and fossil fuels created the economic systems and industrial machines that led to rapid forest-to-farm conversion [10]. This spread of agriculture and the green revolution of the 20th century [11] fueled the dramatic increase in population from 600 million people in 1700 to 8 billion today. We effectively doubled our emissions by using fossil fuels to cut down trees.

The upshot: Food alone is responsible for more carbon emissions than all fossil fuels burned to date [12](Figure 1).

Figure 1. Agriculture is responsible for more carbon emissions than all fossil fuels burned to date across industries, largely because of land-use change. These values (1.7 trillion tons of CO2 from land use change and 0.1 trillion tons from fossil fuels burned for agriculture) don’t even account for the majority of current day agricultural emissions (see left panel “Agricultural processes”): methane from cows and waste decomposition. Allowing land to return to forests and prairies represents the potential to sequester the same enormous amount of carbon emissions. See footnotes for references, calculations, and caveats.

The silver lining of these emissions is that the process is reversible: Allowing agricultural land to return to its forested state could absorb the same staggering amount of CO2. Converting to renewable energy can prevent emissions (carbon neutral); changing the way we eat could actually absorb emissions (carbon negative). So while we can’t stop growing food, improving land-use efficiency is one of our most powerful tools to combat climate change. Not to mention that none of the above gets at the inherent value of biodiversity and natural ecosystems [13].

Cows (beef and cheese) are the least efficient food

Of the different foods we eat, cows are uniquely inefficient. In every metric (land-use, carbon emissions, water, pollution), food products from cows are often the worst by a large margin [14]. They are especially land-intensive, with 41% of the land area of the United States used for cow pasture or feed—land that might instead be forests or grasslands [15].

Cows also produce greenhouse gases directly. They are one of the two largest sources of anthropogenic methane emissions [16]—have you ever admired the smells on I-5 near Coalinga, CA?—and, along with other livestock, contribute 15% of annual global greenhouse emissions—more than all of transportation [17]. Cows are inefficient as food because they require a lot of land, grow slowly, and use 83% of the energy they get from plants to stay warm and walk around instead of making beef or milk [18]. Cows are so inefficient that, after beef and lamb, our most inefficient food is cheese [13], not even another meat.

We also raise a lot of them—more than 1.5 billion globally [19]. Cows outweigh humans [20]. They also outweigh chickens by 12 times [21].

Compare this inefficiency with plants: The entire world’s protein needs could be met by a soybean farm the size of 1% of global habitable land [22] or less than eight times the size of Iowa. Satisfying this need with cheese would require 120% of global habitable land or a farm covering the entire continents of Asia, Africa, North America, South America, and Europe (Figure 2). To do this with beef alone, we’d need 955% of habitable land or nine more planets [23]. What’s more, soy and many other plants [24] don’t emit methane and require less water, machinery, fertilizers and pesticides simply because it’s more efficient to grow a pound of soybeans than to grow 7–10 lbs of soybeans, feed them to a cow, and get a pound of beef or cheese.

Figure 2. Cows are an inefficient way to create protein from land that could be forests or grasslands.

We need to stop eating cows and start eating plants. But there’s one problem: cows and their milk are delicious. The sizzle of a steak, the juiciness of a burger, the stretch of pizza: no one can deny that cows make fantastic foods from plants that are way less fun to eat. For much of history, they provided critical nutrition in nonindustrialized food systems where calories and easily digestible protein were rare, and they often did it by grazing on land no longer suitable for agriculture [25]. For these and other reasons, the meat and dairy industry grew to its current astonishing scale, forcing us to ask an uncomfortable question: will fighting climate change force us to give up foods we love?

Tezza uses microbes to make anything delicious

In food, only two things matter—taste and cost [26]. Without both, a food cannot be globally dominant.

The cheapest and most sustainable foods we make today are plants. We farm corn and soy in such volumes not because we love to eat them but because they are efficient, and efficiency—doing more with less—is the heart of sustainability. A big problem with corn and soy is that they aren’t that tasty. So we use inefficient cows to convert that corn and soy into something we actually want to eat: beef and cheese. 

At Tezza, we take a different approach: We take the most sustainable, inexpensive plants available and make them delicious. We do this with microbes.

Fermentation was humanity’s first biotechnology, providing a simple way to transform cheap but not particularly tasty ingredients like milk and wheat into delicacies like cheese and beer. During fermentation—which is distinct from precision fermentation [27], which targets a specific molecular product—microbes digest proteins, carbohydrates, and fats, enhancing the underlying ingredients with three amazing benefits:

1. Better nutrition by increasing digestibility, providing additional vitamins and minerals, and acting as probiotics

2. Preserving foods by creating conditions (e.g., high acid) that inhibit spoilage and pathogens

3. Rich flavors from the small molecules resulting from microbial digestion (e.g., the nuttiness of parmesan)

We are modernizing the discovery of fermented foods. For the last 10,000 years, humans have discovered fermented foods by accident (“Dude, I dare you to eat that”) [28]. This innovation-by-accident means that the possible delicious pairings between ingredients and microbes have been severely under-researched. Because of the essentially infinite diversity of microbial ecosystems, we focus on finding the microbes that transform whatever ingredient is most sustainable, cheap, and nutritious into something delicious. Our searches may result in familiar foods from unfamiliar ingredients (e.g., cheese made from cheap plants) or entirely new categories of fermented products.

We’re starting with 🧀

We aim first to make a cheese from sustainable plants that tastes better and costs less than commodity dairy cheese. We chose to start with cheese for five reasons:

1. Cheese is the third-most inefficient food behind beef and lamb

2. Despite advances in plant-based milk (thanks Silk and Oatly!) and beef (thanks Impossible!), plant-based cheese remains unsatisfying [29]

3. Cheese is a fermented food, giving us a path to use microbes to make something tastier and cheaper

4. Seventy percent of the global population is lactose intolerant [30], which means that a delicious nondairy cheese would have a motivated customer base

5. We love eating cheese

Cheese was one of the first fermented foods. The flavors that people love in cheese—the funk of a camembert or the sharpness of a cheddar—don’t come from milk, which is bland. They come from the metabolism of microbes. Cheese is not a dairy product; it is a microbial product. Thus, our approach is to discover microbial ecosystems that transform plants into the flavors we love in cheese. We are creating a new category of cheese, akin to the creation of cheese from cow or goat milk.

In addition to flavor, texture is the other pillar of taste [31]. Instead of matching cheese’s ooey-gooey texture by replicating the precise molecules in cheese—which would be expensive—we aim to replicate those melting and stretching functions by biochemically and physically manipulating inexpensive ingredients. Many molecules from the natural world melt and stretch because of specific molecular structures, and we use these rules and patterns to our advantage.

Meat and dairy are some of the most expensive commodity foods, despite massive subsidies from national governments, which keep them artificially cheap [32]. Eating plants is cheaper than feeding those same plants to cows and then eating the cow or its milk. By transforming supremely inexpensive plants—like soy and corn—we can deeply undercut dairy cheese on the cost of ingredients (Figure 3) [33].

Figure 3. We aim to beat dairy on cost by 2X at scale using inexpensive, sustainable, nutritious plants. Despite large government subsidies for dairy, our approach allows us to beat dairy cheese on ingredient costs, something that cannot be said for cheese made with nuts or engineered proteins.

Although we focus on taste and cost as the drivers of food decisions, they are only proxies for the fundamental purpose of food—nutrition. Our approach provides all the health benefits of fermented foods while avoiding the health concerns of dairy. Making a delicious nondairy cheese would mean that many people wouldn’t have to choose between eating cheesy goodness and feeling like garbage an hour later.

We also love cheese—its depth of flavor, its comforting richness, its diversity across cultures, its stockpiling in a cave by the U.S. government [34], its application in fart jokes [35]. Given the calamitous topics discussed here, we might most relish our ability to laugh at ourselves. We’re not saving the world; we just make cheese.

Feed the next trillion with us

By pairing new food ingredients with the right microbes, we accelerate the discovery of delicious, cheap, and nutritious fermented foods and create aged cheese at a fraction of the cost of dairy.

We fed the last 100 billion people using inefficient tools like rocks tied to sticks and animal agriculture. Join us to invent smarter ways to feed the next trillion.