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Slaves to Nitrogen

by Ron Shigeta

The world demand for protein is growing fantastically even as inventory is running low. The solution is a new green revolution to bring nitrogen into food faster to avoid catastrophic famine.

A story published last month in the NYTimes about forced labor on fishing boats in Asia opens eyes to how drastically the sourcing food on our plate has changed. Promised a job, men are boarded on ships, where they are put on duty 24/7, can get beaten and maybe just as bad, are often not paid at all for their work.

As reporters talk to one of the shipmasters, one phrase caught my eye:

The boat’s Thai crew master, Tang … ticked off a list of the pressures on deep-sea captains. Fuel costs eat up about 60 percent of a vessel’s earnings, double what they did two decades ago. Once fish are caught, storing them in melting ice is a race against the clock. As fish thaw, their protein content falls, dropping their sale price … because deep-sea fishing boats work on commission, “Crews only get paid if we catch enough.”

This is an awful job; Tang has very little reason to be doing this either. What Tang is selling is not fish by weight — its the protein in the fish alone. Protein for feed for fish farms, for pets, not pork and chicken for the dining table- feeding the fish we farm and our pets is getting harder to do. Tang is an operative of the world Nitrogen economy, a shadow market that will dictate how 9 billion people will eat in the next 30 years.

Protein is Life and limited by Nitrogen

Around 3.2% of the weight of any living thing is nitrogen. Nitrogen is the limiting factor as to living things growing — its the hardest part of proteins for living things to obtain.

If DNA is the program of life, proteins are life itself. Produced from amino acids according to the information stored in the genome, proteins transform what we eat into vitamins, fats and amino acids. Proteins transform energy into motion, thought, impulses and desire. And proteins are made primarily of carbon, hydrogen, oxygen and nitrogen. Of these, bio-available nitrogen is the hardest to get, limiting the number of living things possible.

Before the 20th century, bio-available (‘fixed’) nitrogen came entirely from slow growing bacteria and algae that live beneath under the earth/sea surface. Taking the nitrogen out of the air (which consists of 70% inert nitrogen gas) mixing it with hydrogen under intense heat and pressure to produce ammonia (a biologically useful form of nitrogen), the Haber-Bosch process was the first modern short cut in the world Nitrogen cycle.


Increasing the amount of nitrogen in the world ecosystem, industrial fertilizers allowed human population to grow beyond about 2 billion for the first time in history.

Today, artificial fertilizers consume ~4% of natural gas worldwide and about half of the nitrogen fixed in the world every year is produced by industrial processes descended from Haber-Bosch.

We need a Nitrogen Revolution which hacks the world Protein Economy

That brings us back to Tang and his unhappy crew. Now days the World Nitrogen Economy has a different problem. Haber-Bosch makes plenty of bio-nitrogen, but its in the wrong place. Nitrogen from our waste streams and agricultural runoff are causing red tides and even so, it looks as if there might not be enough food for humanity in 20 years. All the fish being collected for cheap protein are an attempt to move nitrogen up the food chain so we can eat it. The oceans are a major example. Over a third of the humanity eats fish as a major protein source and 98% of fisheries in the world are fully or over exploited.

Human beings satisfy their nitrogen needs for protein by eating digestible forms of nitrogen in plants or meat. Population growth is no longer limited by the production of fixed nitrogen, but rather by the ability of agriculture to turn the crude nitrogen pool — both chemical fertilizers and recycled nitrogen back into human consumable protein.

The solution is to replumb the world nitrogen cycle to make it more efficient, leave some fish for the 22nd century and avoid famine. Here are examples of Nitrogen Economy shortcuts for the 21st century.

  1. Meat without the animals. Expensive protein sources like meat can be replaced with plant products. Cutting animals out of the food chain eliminates the need to feed the animal, raise it up, just to eat it. There are quite a few companies doing this already. Some are making meat-like foods out of plant proteins (I call this Mock Duck Tech): Impossible Foods, Hampton Creek, and Ripple Foods are examples.
  2. Microbial Food. Beyond that, its possible to take nitrogen entirely from nitrogen salts (fertilizer) and Ag byproduct (like starch from leaves) to make food directly. Invitro Meats and Modern Meadow grow their meat directly from cells, Clara Foods brews egg whites from yeast.
  3. Agtech. GMO plants produce more, taste better, last longer, are more nutritious, resist fungal, repel insect attacks. Properly planned genetically modified organisms are the products of tools and can really add to the value of the foods we have.
  4. Reuse / Recycle. About 30% of all food grown is wasted. Although we want to overlook it, human waste accounts for a large percentage of nitrogen leaving the economy. Rather than overload and imbalance the environment, it would be very efficient to get it back into food form faster. Can we grow cheap protein for feed applications from sterilized waste streams?
  5. Alternative protein sources. Faster growing, protein rich crops can add to the modern diet. Quinoa is a popular new protein source, but crickets, duckweed, and algae are candidate sources for protein. They can all be cultured to grow to harvest much more frequently than conventional crops.
  6. Farm Tech. Using automation, data and enclosed greenhouses can reduce agricultural runoff and make more efficient use of water and nitrogen fertilizers. Hydroponic and aeroponic agriculture technologies get nitrogen and other nutrients into the plant more efficiently, so that crops can be harvested in a fraction of the time and year round.

All of these ideas are enhancing the efficiency of our conventional Agriculture. While lots of people will continue to eat only organic food, looking at the system as a whole will be necessary to feed all of us with the greatest possible quality and safety.

Ron Shigeta is a BioTech VC interested in the Future of Food.

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