3D-printed, self-cooking cookies are here

In the future, we might walk into a bakery, type “owl-shaped chocolate cookie with a honey glaze” into a screen, and watch a machine not only print that cookie 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 step further: they’ve taught artificial intelligence to handle the tricky part of designing the 3D food shapes too.

The work, led by Connie Kong Wai Lee and colleagues at the Hong Kong University of Science and Technology and published in Advanced Materials, combines three big ideas: 3D printing, simultaneous cooking, and AI-driven design. Their results could change how we make customized food at home, in restaurants, and even in hospital kitchens.

3D 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 opens the door for bacterial contamination. Worse, post-cooking shrinkage can turn your adorable 3D-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 the whole product in an oven, they use a cone-shaped infrared heater made of laser-induced graphene (LIG), a super-thin, flexible material made by zapping polyimide 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 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 100°C.

The energy savings are impressive too: their LIG heater runs at about 14 watts, while a kitchen oven gulps down more than 1000 watts. And because the cooking is hyper-local, the food retains moisture better, leading to improved texture.

Yes, they tested for bacteria Food safety isn’t an afterthought. The researchers compared cookies made with their infrared-on-the-spot cooking to those baked in a conventional oven or air fryer. At 100°C, the in-line method had the fewest bacterial colonies after 48 hours, thanks to consistent heat applied to each layer as it was formed. At 150°C, all methods eliminated bacteria, but the print-and-cook system still won on efficiency and shape fidelity.

AI as the pastry chef Then comes the fun part: design. Making your own printable 3D food shapes usually means wrestling with CAD software, which is about as appetizing as raw flour paste. The team solved this by bringing in generative AI.

Using DALL·E, they asked for simple 2D shapes like a gingerbread man or a rabbit, and then fed the images into a Python script that automatically turns them into 3D printable files. The process is simple enough that even someone with no modeling skills can do it. Want your cat’s silhouette in cookie form? Just describe it to the AI, set the height, and hit print.

The combination of precise heating, 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 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. In the world of food, appearance matters almost as much as flavor, so that’s a win.

We might still be a few years away from every household having a countertop “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.

If you want to learn more, the original article titled "Advanced 3D Food Printing with Simultaneous Cooking and Generative AI Design" is available on Advanced Materials at https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.202408282.