University develops leak-proof food bowls from leaves

Concern over the rising use of polluting styrofoam containers has encouraged a research team at Naresuan University to develop a process to make watertight, degradable food bowls from leaves

...

Through trial and error, the team found that leaves of the thong kwao (bastard teak), sak (teak) and sai (banyan) trees are the best to use for the containers.


Full article here.

These are beautiful! Reminds me of Guatemalan tamales, which are steamed in plantain or other large tropical leaves. The leaves are unfolded and become the plate!

Bowls made of leaves, very siilar to there, are very common in India. Unfortunately, styrofoam bowls and paper plates with a silvery layer are becoming more common as they look more modern and fancy.

Oh wonderful North American permies - could something like this be made out of Kudzu?

Jay Angler wrote:Oh wonderful North American permies - could something like this be made out of Kudzu?

I don't know if the leaves of kudzu would be big enough? But, the Empress Paulina - also considered invasive, here - have enormous leaves. They're also a gently medicinal tree, so they might be a good candidate.

Biggest leaved native trees in my area that I know of are Catalpa & Sycamore.

While I'm thinking about it, maybe this can he expanded to just big leaved plants, in general? Things like Corn Lily or Water Arum maybe?

Burra said, "Through trial and error, the team found that leaves of the thong kwao (bastard teak), sak (teak) and sai (banyan) trees are the best to use for the containers.

I am not sure what these are made of these bowls say Sal leaves with bamboo sticks:

100% NATURAL - No adhesives, No chemicals No plastic or paper is used in any form for making these plates. Its 100% made using only leaves
BIODEGRADABLE - The plates are made by stitching Sal leaves with bamboo sticks and then heat moulded into a plate, which makes them easy to compost / biodegrade

Amazon Link

Amazon also has Palm Leaf Plates:

Amazon Link

And Bambo Disposable Wooden Cutlery Set

Amazon Link

Permies leads me to finding out about so many things that I never knew existed.  Who knew?

In Ethiopia we use the leaves from banana as plate but it is not well shaped like this. How can we get it in a shape of a plate ? Anybody an idea?

Very interesting. I look forward to seeing these available. Would be interested in making some but I don't think there going to tell anyone how they do it

Krista Haest wrote: How can we get it in a shape of a plate ? Anybody an idea?

Amazon also has Palm Leaf Plates:

Amazon Link

How Palm Leaf Plates are Made

I assume that the heated mold press is maybe fusing natural waxes/resins in the palm leaves that help lock them together and hold form, but not sure.

My work has bamboo pulp plates and bowls. Pure white so clearly more processed than these, but not styrofoam.

I wonder if big leaf maple could be used like this?

While these would be a great improvement from synthetic dishes, leaves are necessary to trees for every aspect of their servival, and the carbon storage, oxygen production, cleaning of soil and water. We’ve lost 70% of forest east of the Mississippi. What we have must be maintained and cared for to slow climate change.  

Eve Cimino wrote:While these would be a great improvement from synthetic dishes, leaves are necessary to trees for every aspect of their survival, and the carbon storage, oxygen production, cleaning of soil and water. We’ve lost 70% of forest east of the Mississippi. What we have must be maintained and cared for to slow climate change.  

I absolutely agree. However, part of encouraging humans to care about a forest, is to have them interact with that forest in a meaningful way. There are coppice rotations in England that demonstrated that in a managed rotation, trees with a typical lifespan of the low hundreds, can live for a 1000+ years. Does that mean I think all forests should be coppiced? Absolutely not! It's one tool in the permaculture toolbox.

Unfortunately, in the greater world, too many humans see a "forest" as something to be exploited or turned into a mono-culture. If you're here to learn just how permaculture *isn't* that attitude, be prepared to drink from a fire-hose! Here, we're all about working *with* that forest - accepting its gifts, assisting it to benefit us and nature to as great an extent as possible.

You mention a loss of 70% of "forest" east of the Mississippi. How much of that forest loss is due to human disturbance that's not been "undone". I'm reading "Braiding Sweetgrass".  The author is a biologist and identified that as the forest reclaimed worn-out farmers fields near her, the trees returned, but many of the understory plants that supported and were supported by the trees did not. She made an effort to help that. However, the attitude of "trees are just a crop to harvest" prevailed when one of her neighbors clear-cut the acreage taking every tree of value, rather than selective harvesting, to work with the forest. Finding ways to help humans see the benefits of the trees still standing, and to create value-added products on a small scale to support a healthy rural economy, may be an important short term way to encourage more humans to plant trees.

Another thing to think about. If a person plants there acres in trees, say pine trees. In 20 years or so they clear cut and plant again. After 20 years this person makes enough money to justify doing it again. During that 20 years everyone got the benefit of the trees. Now let's say you tell this person that they can't cut the trees for the good of everyone. This person doesn't cut the trees and at about 25 years (the life span of pine trees) and the trees die. This person has no incentive to plant more so he levels the land and develops it for a houses. He make money and everyone lost the benefits of this person's trees 🌳  

Moral of the story. You have to have balance. Life is multi faceted. Look at all sides before you take a hard stance on something. Remember to give and take. Pick your battles, you can't win them all, so pick the important ones

big leaf aster and fischers ragwort - problem solved

Nick Patterson wrote:big leaf aster and fischers ragwort - problem solved

I like it....then you can just eat your plate rather than compost it!

Saralee Couchoud wrote: Moral of the story. You have to have balance. Life is multi faceted. Look at all sides before you take a hard stance on something. Remember to give and take. Pick your battles, you can't win them all, so pick the important ones

Who says it has to be a battle? How about you propose to that land owner how planting a polyculture of trees, some to grow tall, some to coppice, some that are useful for products like syrup, understory plants like flowers to sell to the bouquet trade, and that he'll make more money, more regular money, and help to support nature at the same time. This is why to me, something like the "leaf dishes" are so awesome. Harvested responsibly from enough trees that no tree suffers unduly, ( some trees respond in a healthy way to "deer browse" for example), and the forest is seen as a resource while alive, rather than only a resource after being cut down.

The fellow in Quebec who dismantled his apple orchard and planted a fruit polyculture, improved the life of his bees so much, that he ended up making more money from honey than he used to make from the apples. So yes, Saralee, life is all about balance! The more we teach people more effect ways to balance the books (just read some of Greg Judy's work in that regard!), the more people will consider "farming the forest", or "planting a polyculture on their front lawn", or "planting a native plant garden in front of their elementary school" rather than our current focus on mono-cultures. I believe we can gently spread that concept if we learn what is possible and encourage people to follow successful examples.

Greg Martin wrote:

Nick Patterson wrote:big leaf aster and fischers ragwort - problem solved

I like it....then you can just eat your plate rather than compost it!

Next question, can we find a way to do this at a "cottage industry" scale. Sell your road-stand produce in edible containers?
We sell eggs - the cartons we use are already biodegradable but are still manufactured from dead trees on an industrial scale, likely requiring at least some nasty stuff in the process.  Could we find a way to produce cartons from leaves, rather than trees? Can it be done cheaply enough that it doesn't do nasty things to our bottom line? It is a much more complicated shape.

They actually have grow pots made out of manure I think. So when you plant the seedlings they already have fertilizer too

Jay Angler wrote:Next question, can we find a way to do this at a "cottage industry" scale. Sell your road-stand produce in edible containers?
We sell eggs - the cartons we use are already biodegradable but are still manufactured from dead trees on an industrial scale, likely requiring at least some nasty stuff in the process.  Could we find a way to produce cartons from leaves, rather than trees? Can it be done cheaply enough that it doesn't do nasty things to our bottom line? It is a much more complicated shape.

So Typing aloud, so to speak....

Assuming we need

a shape

pressure

heat

time

The shape would need two interlocking forms that make a cavity the shape and size of the plate/container. In industry for plastic compression mouding conventionally this would be made of steel: strong, transmits heat, formable to intricate shapes if required.  Wood would be more sustainable, but I'm thinking most woods would not like to be hot and steamy repeatedly? An alternative would be reuse of existing moulds. For a simple shape like a plate or cup you might find glass or ceramic plates that nest together? An egg box would be more complex. (I suspect that a reusable woven basket would be easier! edit - or papier mache)

Pressure is just weight. This is just to compress the leaves into the shape. The higher the pressure the more detail and finer the shape forming will be. There would be a limit to how much pressure you could put on wooden forms, or ceramic plates. A cheese press or flower press might work?

Probably heat and time would be related and if it were too hot for too long the plates would burn. I'm assuming that the transformation here is similar to cooking. You can cook the proteins in eggs at boiling water temperature. I'm imagining a solar dehydrator could be repurposed, or an oven, the top of a stove or airing cupboard.

I don't think it would be a quick process, but you could produce some beautiful things....

I suspect the leaf type is very important. Think what your local leaves look like when they dry out the only ones I have that have any structure when they dry are laurel and rhododendron, neither of which are large enough or edible. The leaves I have that are large enough, burdock, butterbur, rhubarb, dock and horseradish are all soft when they dry so wouldn't work for this use.
I think you need a waxy evergreen leaf to make it easy, and not require some form of support like the bamboo.

There are a few deciduous tree leaves which may be a possibility. I'm thinking Sweet chestnut and that could be a use for the dreaded sycamore too Scandi!

Nancy Reading wrote:There are a few deciduous tree leaves which may be a possibility. I'm thinking Sweet chestnut and that could be a use for the dreaded sycamore too Scandi!

I've not seen a sweetchestnut leaf in years so I don't really remember them how structural they are. Sycamore, oh yes plenty of them and they do have a bit of structure to them, would have to work out a way of sticking them together or it's going to be some very small bowls!

Skandi Rogers wrote:would have to work out a way of sticking them together or it's going to be some very small bowls!

I'm assuming that the heat and pressure of the leaf bowl process actually bonds the original bowls together (I don't think it's single leaves there either?) Maybe I'll have a try next summer - I have a couple of large sycamores although the leaves are generally a bit spotted.

I noticed a lot of these plates were using palm leaves and that palms have waxy leaves that may help them both stick together as well as resist rehydrating from the food placed in them.  My concern with rehydrating too quickly would be the plate or bowl then falling apart in your hands.  I did a quick search for edible waxy leaves and found this article on that topic from The Botanist in the Kitchen.

Hmm....I wonder if lotus or kale leaves have enough wax for this to work out?  Certainly they both are available with large enough leaves!

I was also thinking about the waxy shoots of lamb quarters.  Maybe they have enough wax to act as a tie layer between larger leaves?

Greg Martin wrote:Seeing that they were using palm leaves and that palms have waxy leaves that may help them both stick together as well as resist rehydrating from the food placed in them.  My concern would be the plate or bowl then falling apart in your hands.  I did a quick search for edible waxy leaves and found this article on that topic from The Botanist in the Kitchen.

Hmm....I wonder if lotus or kale leaves have enough wax for this to work out?  Certainly they both are available with large enough leaves!

I was also thinking about the waxy shoots of lamb quarters.  Maybe they have enough wax to act as a tie layer between larger leaves?

Waterlilly leaves? they are waxy, large and round. could be perfect.

Yeah, that's the lotus I meant Skandi.  Thank you for that detail as some might confuse it with the lotus fruit tree otherwise.  The water lily lotus leaves are big enough that we could make platters!