Food Safe 3D Printing


Nothing captures the imagination like the idea of 3D Printed Food. The awe-inspiring idea of 3D printed food perhaps was best captured in the 80s by the classic cartoon The Jetsons.

Who remembers how Poor ol'  loving mum, Jane Jetson "slaving" away in the kitchen by simply pressing a few buttons to cook up instant dinner for the family?

Jetsons by Hanna-Barbera / via Google Image

 

We were inspired to write an article about food and 3D printing after coming across an Ultimaker user's new food startup called Dreampops in our previous post.

Food safety in 3D printing is actually quite complicated and there are a number of things you need to be aware of when exploring food safety in 3D Printing.

Here some of the things to know.

1) Build up of Bacteria

The biggest concern with 3d Printing especially in Fused Deposit Modelling 3D Printers where layer upon layers of thermoplastic are built up to form a 3 dimensional shape, is the risk of bacteria and germs getting trapped within the microscopic spaces between each layer. Although 3D Printers like the Ultimakers are able to achieve layer resolution as small as 30 microns, even the smoothest looking prints will by nature still have small microscopic gaps for bacteria to get trapped in.

 

27x magnification on a FDM printed object Source-formlabs.com

 

Disposable printed objects for one time use shouldn't be a problem, but items you plan to be for repeated use, you must strongly reconsider if 3D Printing is the right tool for the job.

2) Food Safe Sealants

Using Food Safe Sealants is another option some users are using. Products like Food Safe Epoxy Adhesives from Masterbond are used in sealing a 3D Printed object inorder fill up these microscopic gaps, preventing the built up of bacteria.  

Source- Masterbond.com

3) Are your Filaments Food Safe?

ABS is generally considered unsafe to use with anything that comes into contact with food as it contains styrene.

Natural PLA which is biodegradable is a derivative of corn startch and is generally considered food safe. However, some filament manufacturers will belnd additives for color and strength, that may make filament not food safe. Some PLA filaments are designed to be food safe like Colorfabb XT which is a low-odor, styrene free filament. Made with Amphora AM1800 the manufacturers claim they are FDA food contact compliance, and BPA (Bisphenol A) free formulation.

Always check the Material safety data sheet (MSDS) that breaks down the chemical properties and will usually specify whether the product is FDA approved or not. 

Choosing the right material for the object purposes is important. Using PLA for a Coffee cup, although may be relatively food safe, is not an ideal solution as the plastic will become soft in contact with heat. ABS might be a stronger choice but it is not ceritfied food safe and has chemicals that are potentially toxic to ingest. The best solution would be to use a professional 3D printing Bureau that offers 3D Printing ceramic that are food safe like Shapeways.
3d Printed Ceramic Cup by Shapeways (made with the Sake Set Creator)
 

4) Not Dishwasher safe

Thoroughly washing a printed object even with antibacterial soap would generally not be enough to make an object food safe. Unfortunately if you wash a 3D printed object in hot water or with a dishwasher, they will more than likely deform and warp, as they are naturally thermoplastics after all.

PLA is has a low glass transition rate and is definitely not safe to put into a dish washer. Being brittle as well, the printed PLA object can crack whilst being washed.

Nylon SLS parts being washed in a Dishwasher Source- Digits2Widgets

 

5) Length of Food Contact

Cooking utensils like knives and cookie cutters don't come into contact with food or your mouth for very long, so they are generally considered safe. But it is recommended to dispose after use.

#3DPrint Cookie Cutter Source Xyzworkshop

 

3D Printed Cookie Cutters by Stacey McLeod

 

As you can see obtaining, a fully food safe object is quite difficult task. 

So what is the best solution?

Here are some options you might consider.

Food safe Silicon Molds

One solution would be to create a food-safe silicon mould out of your 3D printed objects, like Smooth-on Food safe molds.

An example here is one in chocolate XYZWorkshop had created. XYZ Workshop had printed the mold on their Ultimaker Original. Next they sourced a food safe smooth-on silicon mix which they poured into the 3D printed mold. Once the silicon had cured, the printed object is then removed, chocolate is then tempered and poured into the cleaned up food safe mold. The chocolate end product is actually designed as a Chocolate representation of Melbourne City.

In DreamPops' case they created metal molds out of their 3D prints from their Ultimaker. Casting in metal was the perfect material for making their popsicles, as the metal will conduct the cold best from the liquid nitrogen they pour around the mold.

The Babines Lollipops shop in Paris creates modern lollipops in trendy pop culture shapes that no traditional confectionary would think of. The lollipops are drawn, modeled and then 3D printed on an Ultimaker at the company's lab in Paris. The Facebook 'Like' icon, video game controllers, dollar signs, and anything else that's relevant today can become a lollipop. Using food-safe silicon as mold of the 3D print is created, which is then sent to an artisan confectioner in the Loire. This classically trained craftsman creates the sugar mix for each flavour lollipop and pours them by hand into the silicon molds.

 

Silicon Putty

Recently educators at Scotch College Melbourne organised a printed food workshop within the College. Student had to 3D print an object and a special food safe silicone putty is used to create food safe mold in order to pour chocolate into the negative impressions of the silicone putty.

Scotch College educators engaged with their students by making custom chocolates using these food safe silicon putty

 

The series of photos below shows a step by step of how you might create a food safe mold from a 3D Printed object. 

Press the 3D printed object in the kneaded putty. Ensure that the thickness of the putty is twice the thickness of the printed object. The silicone putty should be allowed to fully cure before removing the 3D printed object. Check the directions of your product.

Chocolate is poured into cured mold.

With a flex of the mold, a perfect chocolate copy of the 3D printed object can be removed from the mold, ready for use.

 

Vac Forming Food molds.

Besides using food safe silicon putty, you can also look at vac forming your molds. Vac forming is a process whereby a sheet of plastic is heated to a forming temperature, stretched onto a single-surface mold, and forced against the mold by a vacuum is formed into permanent objects. 

Vac formers can be found in some makerspaces and workshops. 

Candy Mechanics shows us how they used a 3D scanner, an Ultimaker and a vac former to create customised candy heads.
Recently there was a kickstarter for a desktop vacformer called the Form Box. Their kickstarter video illustrated this use of vacforming to create designer chocolates.

 

 

 *********Disclaimer*********

Although we have listed down some potentially suitable methods of creating food safe products, the article above is intended to inspire readers on the potential applications of 3D printing. 3D printing and the use of any 3D printed parts are at your own risk, we do not guarantee the resulting products will be food safe. Neither Imaginables nor any other Party involved in creating, producing and sharing the story shall be liable for any direct, indirect, incidental, consequential, or punitive damages or injuries arising from food related 3D printing applications. Please consult a food safety expert to obtain further details.

Sources;

All3DP.com-Food safe 3D Printing: 12 Facts you Should Know 

Makeyourownmolds.com- Silicone Plastique® Food Grade Silicone Mold Putty