Circular Biomanufacturing, Sourdough & Bittersweet
How to turn the bioeconomy circular, my beloved sourdough recipe, and extending compassion to eco-anxiety (#58).
💥 Breakthrough: Circular Biomanufacturing
Precision fermentation is already disrupting the food, beauty, and petrochemical sectors. I believe it will be revolutionary in every way – if it can overcome a central process flaw.
Most bioproduction today remains remains stuck in age-old linear thinking where 1 process creates 1 product. It’s how most production has occurred since the Industrial Revolution.
We need more circularity to harness the power of the bioeconomy. Co-product valorization can improve both the business case and the environmental impact of new bioproducts.
Why is circularity important? The lack of circular thinking is partially what doomed algae biofuels a decade ago. Let me explain.
PS: if precision fermentation is new to you, get caught up on my previous post.
Case Study: The Fall of Algae Biofuels
In the 2000s and 2010s, algae biofuel start-ups raised hundreds of millions of public and private dollars for green energy.
Entrepreneurs and scientists believed fuel from fast-growing microalgae could compete with corn ethanol and fossil fuels. It’s because mighty microalgae boast high concentrations of hydrocarbons and energy-rich oils that can be converted into ethanol and biodiesel.
Microalgae were grown in photobioreactors or in lower cost open ponds called “race-tracks,” like the image below. Leading start-ups like Algenol claimed they could produce 8,000 gallons of algae biofuels per acre at scale, far exceeding corn’s yields at 420 gallons per acre.
They believed their algae biofuels could reach $1.27/gal at scale, all while capturing 1 ton of CO2 for every 144 gallons produced. Who wouldn’t invest?
But Algenol faced significant economic and technological hurdles, eventually pivoting away from biofuels into high-value personal care and food supplements. They weren’t the only ones that tried. Oil incumbents like Shell and Exxon also made multi-million dollar investments in algae biofuels they later abandoned.
There are many reasons most algae biofuels ventures pivoted or folded: market conditions, lack of funding, and low fit-for-purpose capacity. But the economic model was doomed from the start. It relied on turning 80% of the biomass into commodity products to drive 80% of the revenue. The nascent technology couldn’t compete with fossil fuels receiving trillions in subsidies.
The business model ignored the presence of high-value compounds like antioxidants, carotenoids, and other nutraceuticals in microalgae – some of which can fetch price points above $1,000/kg. In an integrated biorefinery model, 10% of the biomass could generate 90% of the revenue, which could then fund the transformation of the rest into biofuels.
This is the magic of a circular, multi-product, and integrated biorefinery.
Where We’re At Now: Linear Biomanufacturing
Today, most precision fermentation start-ups are focused on commercializing a single product or ingredient. Some already use waste streams as feedstocks, which is excellent.
But there’s still a long way to go in what I see as the pinnacle of the bioeconomy: circular alt protein biorefineries. Let me give an example of where we are now and how we can get there.
Congratulations! You are the founder and CEO of a precision fermentation start-up and you’ve engineered a yeast to produce a dairy protein.
Your main objective is to commercialize this protein, for which you’ve hopefully conducted a desirability assessment and identified a customer problem to solve. (PS: if this is you and you haven’t, message me and I can help!)
At a (very) high-level, here’s what your production process might look like:
Your yeast will happily ferment in the delicious broth you’ve made and secrete tons of your dairy protein. This fermentation is the upstream processing (USP).
After biomass removal, filtration, and drying, you now have dairy protein powder! Woohoo! This purification is the downstream processing (DSP).
In a commercial-scale run, your whole process might:
💧Use 100,000 kg of water
🍚 Grow 9,000 kg of biomass
🥛Generate 3,000kg of protein
As you are focused on commercializing your dairy protein, you may send the remaining water, biomass, and nutrients down the drain. In the best-case scenario, maybe the biomass is fed to animals or used for anaerobic digestion.
There’s a big opportunity for co-product valorization here, which could improve your business model in the long-term.
Granted – strain engineering, process scale-up, sensory testing, regulatory procedures, and ingredient formulation for one ingredient are difficult as is. It’s going to take a village, if not a whole industry. But given that the unit economics need to significantly improve for commodity proteins, we should explore all avenues to do so.
Where We Should Go: Circular Biomanufacturing
How can precision fermentation learn from the mistakes of algae biofuels? To design circular production processes with multi-product revenue streams.
Here is the same process as above, but with an integrated biorefinery approach:
This process effectively valorizes co-products and waste streams, by:
✅ Treating and reusing 100s of tons of water
✅ Recycling expensive nutrients like phosphorus
✅ Capturing & utilizing the CO2 for other processes
✅ Extracting value from each component of biomass
The biomass – which can outweigh the target product by 3:1 or more – can be a valuable source of fiber, fats, and prebiotics like beta-glucans for many other applications.
At the same time, valorizing side streams can:
✅ Reduce feedstock & media costs
✅ Improve overall process techno-economics
✅ Enhance the sustainability of alt proteins & bioproducts
Start-ups are understandably focused on their first products. But we need to think about building circular biomanufacturing infrastructure for the whole ecosystem to succeed.
There’s a long path towards circular biomanufacturing at scale. But it’s an ideal worth building towards.
Note: in the case of GMO organisms, more safety studies must be conducted to ensure the production of human-safe ingredients.
🥘 Recipe: Sourdough
I’m no longer gatekeeping. Here is my beloved sourdough recipe and technique, honed with love over COVID. Back when I may or may not have hoarded and gone through 50 lbs of flour 👀
If you missed the sourdough bandwagon a few years ago, this is your sign.
The process takes 24h, most of it downtime for fermentation magic. If you’re considering a weekend project, I recommend starting it Saturday morning for fresh Sunday bread. Your besties will thank me later.
PS: If you live in Brooklyn and want some starter, let me know! :)
Thanks for reading this far! I reward you with a mushroom fact 🍄
Mushrooms produce Vitamin D when exposed to the sun, the same way humans do ☀️. This is thanks to a precursor molecule called ergosterol that transforms into Vitamin D under UV light.
Before cooking, leaving mushrooms like cremini, shiitake, or maitake gills-side up for 30 minutes or longer. Much tastier than over-the-counter supplements.
📚 Book: Bittersweet
I read this beautiful book during my recent travels in South East Asia. And it may be the perfect remedy to your eco-anxiety.
In Bittersweet, Susan Cain explores difficult emotions like sadness, longing, and poignancy. Bittersweetness is the chills when listening to sad music; it’s the weight of witnessing threatened wildlife; it’s the wonder in finding beauty in the mundane.
Amidst a tyranny of positivity, we’re often told not to dwell on sad emotions or fears of failure. Susan Cain believes there’s power in embracing these difficult emotions – for healing, connection, and inner peace.
Successes emerges from the transformations in difficult times. Beauty emerges from suffering. And innovation emerges from pain points.
Bittersweetness also has its place at work. “Melancholic leaders” hold an under appreciated power. Their compassion inspires loyalty from their followers, who don’t want to betray them. Their sensitivity makes their employees feel accepted and valued.
After reading this book, I’ve been allowing myself to sit and fully feel difficult emotions that arise – whether it be eco-anxiety, uncertainty, loss, or longing. Holding these difficult emotions with compassion has brought me peace and stillness. I hope it can for you, too.
Some favorite quotes as food for thought:
“Is creativity associated with sorrow, longing–and transcendence? Whatever pain you can’t get rid of, make it your creative offering.”
“Everything that you love, you will eventually lose. But in the end, love will return in a different form.”
“Bittersweetness is not, as we tend to think, just a momentary feeling or event. … It’s an authentic and elevating response to the problem of being alive in a deeply flawed yet stubbornly beautiful world. [It] shows us how to respond to pain: by acknowledging it, and attempting to turn it into art, the way the musicians do, or healing, or innovation, or anything else that nourishes the soul.”
Thank you for reading – BRB next week ✌️
🥘 Recipe: Sourdough
Ingredients (2 loaves)
600g bread flour or all-purpose flour
260g whole wheat flour
600mL warm water
17g salt
70g sourdough starter (make your own or buy here) + 70g water + 70g flour
Instructions (24, active time 2h)
Video instructions by Joshua Weissman here.
First of all, feed the starter. Add 70g of mature sourdough with 70g of lukewarm water (~80F or ~26C) and 70g of flour in a mason jar large enough to triple in volume. Leave to rest in a warm environment for 6 hours (for example, oven with the light on), leaving the lid partially open.
30 minutes before the sourdough is finished, make the dough. In a large mixing bowl, mix the bread/all-purpose flour, whole wheat flour, salt, and lukewarm water (~80F or ~26C). Place the mixing bowl next to the sourdough for the remaining half hour.
Then, incorporate the sourdough starter by spreading over the dough, then poking holes throughout the surface. Mix and knead by hand until fully incorporated. To give it some extra stretch, complete a few “pull and folds” to give the gluten structure (see video above).
Let the dough ferment in a warm environment, ideally 78-80F, for a total of 3.5h. Every 30 minutes, lift the outside of the dough up and over to the opposite side, without tearing. Repeat until you have gone all the way around the dough, then let sit until the next repetition.
Using a bench scraper, transfer the dough over to an unfloured surface and divide in half. Using the bench scraper, pull the dough against the unfloured surface until forming boules. Transfer over to floured bannetons, place in a plastic bag, then refrigerate in the fridge for 12-14 hours.
In the morning, preheat an oven to 475F with a cast iron dutch oven. When it reaches the temperature, pour in enough flour to cover the inside, then add one of the doughs. With a razor blade or sharp knife, make a slit in the center along the length of the loaf, or in whatever design you’d like.
Bake at 475F for 25 minutes with the lid, then 25 minutes without the lid until golden brown. Repeat for each dough. To save time, you can transfer one dough from the dutch oven to a baking tray after the first 25 minutes so you can place the second dough. Enjoy your family or besties :)
About Me
Hi there! My name is Nathan Paumier – I’m an avid reader, food enthusiast, and climate optimist.
BRB w/ Nathan P, your 5-min weekly dose of information to inspire climate action. I started this newsletter after frequent questions on food tech, reading recommendations, and my secret recipes.
Want to get in touch or chat further? Anything you’d like to hear more of?
Forwarded this email?
Subscribe below to receive an email from me every week.
No spam, just quality ingredients.