How it works

Making dairy with the magic of flora

background | our process | teaching flora

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Animals are very good at eating plants and
turning them into high-quality protein
that’s why animal protein has been a part of
the human diet for well over a million years.

Not all sources of protein are equally bioavailable to the body. Nutrition experts have developed ways to quantify protein quality. According to the most common method, the Protein Digestibility Corrected Amino Acid Score (PDCAAS), only three proteins have a “perfect” score: milk protein, egg protein, and soy protein. (Proteins can also be blended to achieve a higher level of quality, such as combining pea and rice protein.)

In 2013, the Food and Agriculture Organization (FAO) of the United Nations recommended replacing PDCAAS with a new method, the Digestible Indispensable Amino Acid Score (DIAAS). In short, DIAAS looks at how much protein makes it through to the end of your digestive tract without being used by the body, while PDCAAS is a cruder estimate across the entire digestive tract.

More reading

But it turns out that microflora – tiny
things like yeast and bacteria that are too
small to be seen without a microscope –
can produce much more protein relative
to their body size.

You’ve probably heard of “flora and fauna” – the words for the collective plant and animal species, respectively, found in a specific biome. The word “microflora” started being used a few decades ago in the contexts of medicine (e.g., to describe the bacteria and other organisms living in the digestive tract) and agronomy (e.g., the bacteria and other organisms living in soil).

Today, a variety of endeavors are underway across the world to harness fermentation to produce new kinds of food, materials and medicines – they may use bacteria, yeast, fungi, or algae, but qualitatively, they all follow essentially the same story outlined on this page. Since the similarities are far more important than the differences, we’ve found it helpful to talk about microflora, or flora for short, as a catch-all term for any microorganism cultivated by humans to make a product.

If you’re curious, Perfect Day’s first protein is produced in a type of fungi (more on that below).

The power of

For centuries, we’ve relied on enzymatic proteins made by flora to
produce leavened bread, to convert the sugar in grapes to wine,
and of course, to turn milk into products like cheese and yogurt.

This idea of harnessing flora to produce better food and drink is
called fermentation, and has been part of human culture longer
than the concepts of writing or money.

Yeast + sugar -> carbon dioxide bubbles -> leavened bread.

Wine and beer:
Yeast + sugar -> alcohol (and carbon dioxide, which is why beer and some wines are effervescent).

Cultured dairy:
Bacteria, yeast, and/or fungi (in other words – flora) + lactose -> lactic acid and yummy flavors.

As you can imagine, there are countless additional examples of fermentation used throughout history.

Over the millennia, we’ve come to
appreciate just how flexible flora can be.
They can be fed nearly anything, and they
can be trained to produce nearly anything.

That’s why today, the humble process of
fermentation is humanity’s go-to method
for producing medicines, food ingredients,
and even beauty products

First flora-derived medicine:
Insulin, 1978

First flora-derived food ingredient:
Rennet, a dairy enzyme (!), 1982

But until 2014, no one had ever thought
about producing animal-sourced foods using
flora. That’s where Perfect Day came in.

We realized that if flora could make anything
efficiently, they might even make animal
protein better than animals themselves.

So, how do we do it?

The process itself is surprisingly simple.
All we have to do is feed sugar to our
friendly flora, and they produce a huge
amount of protein.

We’ve trained the flora to produce
whey protein, the same exact protein
found in cow’s milk.

We also have flora that produce caseins – the other major fraction from milk.

Using simple filtration, the protein
is separated from the flora and any
remaining sugar – and then dried
into a powder.

The filtration and drying is actually almost identical to how the dairy industry currently separates protein from milk.

Because it’s the same kind of protein
that food makers are already familiar
with, it’s simple to use flora-made dairy
protein in exactly the same ways you’d
use dairy protein from cow’s milk.

But the coolest thing we can do with our
protein is to combine it with water,
plant-based fats, vitamins and minerals,
in exactly the same proportions you find
in cow’s milk.

What we get… is milk.

Only animal-free.

The FDA definition of milk stipulates that it must be a lacteal secretion, practically free from colostrom, from the complete milking of adult cows.

So, in a legal context, it’s not exactly milk. It just looks, smells, tastes, and performs like milk.

From here, because it has the power
of real dairy protein in it, our
animal-free milk can be turned into
all your favorite dairy products!

How do you
teach flora
to make milk

Obviously, natural microflora do
not produce animal proteins.
There’s more to the story.

One of the coolest things about
biology is that the cells comprising
every creature on Earth can speak
the same language: DNA.

Inside of every cell is a vast library of
proteins it knows how to make. Each of
these proteins is described by a single gene.
A gene is just a specific sequence of DNA.

So, if proteins are the heroes in our food,
you can think of a gene like the story
behind each hero, and DNA like the book
that contains the story.

We like to say “DNA” to talk about the tangible molecules, and “gene” to talk about the intangible data those molecules represent (i.e., a string of A, T, C, G).

More reading

Like stories from books, genes
can be digitized. They’re just
information, after all.

It turns out that a huge number of natural
genes have already been digitized. This is
especially true for genes that correspond to
important proteins – like casein and whey,
the major milk proteins.

So it was easy for us to find the genes…
and use the now-common tools of biology
to “print” the genes back into DNA sequences
that a cell can read.

This process is all totally animal-free.

We now had the milk protein genes in a form
that could be read by any cell. What kind of
cell should we work with? Just like cows are
the best milk producers in the animal world,
it turns out there was a winner from the
world of microflora, too.

60 years ago, on the Solomon Islands, a
natural microflora was discovered that
was able to produce a huge amount of
protein, and was a particularly good
“reader” of genes.

Today, this friendly flora, known as
Trichoderma, is one of the top
performers in the bioproducts industry.

It seemed like a no-brainer for us to
work with the same time-tested winner.

Specifically, it was discovered producing enzymes that allowed it to eat through canvas and other materials made of cellulose.

More reading

The modern dairy cow is a domesticated
descendant of the aurochs, a natural animal
which lived 10,000 years ago in Eurasia.

Perfect Day took a similar path to make
animal-free milk possible, using modern tools.

By combining the animal-free milk protein
genes with some spores of Trichoderma, we
successfully domesticated the world’s first
dairy-producing flora.

To be clear, we’re talking about bioengineering.

Cows only had to be domesticated once –
now you don’t need to be experienced in
animal breeding to produce milk. You just
have to milk the cow.

Likewise, now that our dairy-producing
flora has been brought into the world,
the hard part is over. Anyone who knows
how to run a fermentation tank can make
animal-free milk!

Or any other flora-made product; that’s the whole point!

And as it turns out, Perfect Day is only
one of a huge number of companies that
are using flora to produce new products
in kinder, greener ways.

This means that in the coming years,
many people all over the world will be
building fermentation tanks and learning
how to operate them to make all kinds of
things, old and new.

It’s all part of doing more
with less and creating a
healthier, happier world

that everyone can enjoy.