3D-printed, self-cooking cookies are here

Researchers at the Hong Kong University of Science and Technology developed a 3D food printing system that simultaneously cooks each layer using an infrared heater made from laser-induced graphene, improving shape stability, efficiency, and food safety. The team also integrated generative AI to automatically create printable 3D designs from simple text prompts, making customized food production accessible to non-experts.

Read the full article at https://www.paperleap.com/blog/articles/3d-printed-self-cooking-cookies-are-here-0cccc4

Episode Transcript

Speaker 1 (00:00):
Welcome to the paper Leap podcast, where a science takes
the mic. Each episode, we discuss cutting edge research, groundbreaking discoveries,
and the incredible people behind them, across disciplines and across
the world. Whether you're a curious mind, a researcher, or
just love learning, you're in the right place. Before we start.

(00:21):
Don't forget to subscribe so you never miss an insight.
All the content is also available on paper leap dot com. Okay, ready,
let's start. In the future, we might walk into a
bakery type owl shaped chocolate cookie with a honeyglaze into
a screen and watch a machine not only print that cookie,

(00:42):
but cook it layer by layer as it's being made.
No transferring it to an oven required, no waiting around,
no risk of the dough collapsing into a sad pancake.
That's exactly what a team of researchers in Hong Kong
has just made possible. And they've gone a start further.
They've taught artificial intelligence to handle the tricky part of

(01:04):
designing the three D food shapes too. The work led
by Kannie Kongwai Lee and colleagues at the Hong Kong
University of Science and Technology and published in Advanced Materials.
Combines three big ideas three D printing, simultaneous cooking, and
AI driven design. The results could change how we make

(01:26):
customized food at home, in restaurants, and even in hospital kitchens.
Three D food printing is not new, but it's always
had an awkward workflow. You first print your dough or
puree in a complex shape, then you move it to
another machine an oven, fryer or steamer for cooking. That
transfer step is slow, risks deforming the delicate structure and

(01:50):
opens the door for bacterial contamination. Worse, post cooking shrinkage
can turn your adorable three D printed rabbit into something
that looks like it's been through a washing machine. The
Hong Kong team's answer is a tiny but mighty heating
system built right into the print head. Instead of blasting

(02:10):
the whole product in an oven, they use a cone
shaped infrared heater made of laser induced graphene, a super thin,
flexible material made by zapping polyamide film with a laser.
This material is lightweight, energy efficient, and excellent at radiating heat. Evenly.
Mounted around the printing nozzle, the heater warms each layer

(02:34):
of dough. The moment it's extruded. That means the structure
is solidified before the next layer arrives, preventing collapse. It's
a bit like building a snowman and freezing each section
in place before adding the next one, only here the
freezing is actually cooking at over one hundred degrees celsius.

(02:54):
The energy savings are impressive too. Their lig heater runs
at about fourteen watts while a kitchen oven gulps down
more than one thousand watts, and because the cooking is
hyper local, the food retains moisture better, leading to improved texture.
Food safety isn't an afterthought. The researchers compared cookies made

(03:16):
with their infrared on the spot cooking to those baked
in a conventional oven or air fryer at one hundred
degrees celsius. The inline method had the fewest bacterial colonies
after forty eight hours, thanks to consistent heat applied to
each layer as it was formed at one hundred and
fifty degrees celsius. All methods eliminated bacteria, but the print

(03:37):
and cook system still won on efficiency and shape fidelity.
Then comes the fun part design, making your own principal
three D food shapes usually means wrestling with CAD software,
which is about as appetizing as raw flour paste. The
team solve this by bringing in generative AI using DALI.

(03:59):
They ask for so simple two D shapes like a
gingerbread man or a rabbit, and then fed the images
into a Python script that automatically turns them into three
D printable files. The process is simple enough that even
someone with no modeling skills can do it. Want your
cat's silhouette and cookie form, just describe it to the AI,
set the height, and hit print. The combination of precise heating,

(04:23):
food safety, and easy customization could be useful in hospitals,
care facilities, or even space missions, anywhere you need personalized
nutrition in a safe, compact, and automated system. It also
opens the door to multi ingredient printing, where different layers
could have different textures or nutritional profiles. The researchers even

(04:45):
did a small blind taste test. The verdict. Testers thought
the infrared cooked cookies looked better and had just as
good a taste and texture as the oven baked ones.
And the world of food appearance matters almost as much
as flavor, so that's a way we might still be
a few years away from every household having a countertop,

(05:05):
print and cook food station, but this work shows it's
technically feasible, and when it happens, your kitchen might look
less like a place for pots and pans and more
like a mini design studio where dinner is printed to order.
That's it for this episode of the paper Leaf podcast.
If you found it thought provoking, fascinating, or just informative,

(05:29):
share it with the fellow science nerd. For more research
highlights and full articles, visit paperleaf dot com. Also make
sure to subscribe to the podcast. We've got plenty more
discoveries to unpack. Until next time, Keep questioning, keep learning,