How To Make Food Safe Pottery

When creating pottery in your home, often the main consideration is the look and finish of the piece. Sometimes however, pottery is crafted to be functional and needs to have certain characteristics to ensure that it is suited to its intended use. This is particularly true with pottery that is intended to be used for food. There are a few considerations that need to be made when creating a food safe pottery piece.

What does a food safe pottery design need to look like?

It’s important to consider the pitfalls of a pottery piece design before creating a food safe project. Some designs do not lend themselves to food safe items. This is particularly true of any designs where there are crevices and nooks which can harbor bacteria or are difficult to clean. A rough finish can also ensure that the piece cannot be easily cleaned, so it’s best to consider something smooth and easily maintained over consistent use.

Food safe pottery also needs to be strong. An intricate design may be nice for a while but after continuous washing and use, the integrity of the ware can be compromised and will eventually break.

Understanding food safe clay

The type of clay that you use is of course a vital aspect of whether it is food safe. Here we look at some different types of clay and whether they are food safe. Stoneware and porcelain are generally considered to be the best for food safe types of clay, as they are fired at high temperatures that make them less porous and less likely to leach chemicals. Earthenware, however, is more porous and is more likely to leach chemicals.

Is air dry clay food safe?

If you use air dry clay regularly, you might be wondering whether this type of clay is safe for use in kitchenware and food-related projects. Well, the good news is that air dry clay can indeed be food safe!

Air dry clay is a type of clay that dries naturally when exposed to air, without the need for kiln firing. This means that you can easily create food-safe items like bowls, plates, and mugs using air dry clay. However, it's important to note that not all air dry clays are food safe, so be sure to check the label or manufacturer's instructions before using it for food-related projects.

To ensure that your air dry clay creations are safe for food use, you can follow a few simple steps. First, make sure to choose a high-quality air dry clay that is labeled as food safe. This will give you peace of mind knowing that the clay has been specifically formulated for use with food. Second, be sure to seal your finished pieces with a food-safe sealant or glaze. This will create a protective barrier that prevents any contaminants from leaching into your food.

Is polymer clay food safe?

Polymer clay (also known as oven bake clay) is a popular choice among crafters and artists due to its versatility and ease of use. However, when it comes to using polymer clay for food-related projects, there are some important considerations to keep in mind.

Unlike air dry clay, polymer clay is not naturally food safe. The clay itself is not toxic, but it does contain plasticizers and other chemicals that could potentially leach into food if not properly sealed or protected. Therefore, it is crucial to take precautions when using polymer clay for items like plates, bowls, or utensils that come into contact with food.

To make polymer clay food safe, use the same process as the air dried clay above. It's important to note that while polymer clay can be made food safe, it is not recommended for items that will come into direct contact with high temperatures, such as baking dishes or hot beverage cups. The heat can cause the clay to release toxic fumes or break down, compromising its safety.

Whatever clay you choose, it is best to ensure that it is sealed by a finish or glaze to prevent any dangerous leaching into the food.

How should food safe pottery be decorated?

To be safe, try to avoid decorating any part of the pottery that comes into contact with food. There are special food safe paints that you can purchase from most art and craft stores, which you can apply with a brush or stamp. Ensure that you purchase ceramic paints, which work better and last longer than acrylic paints.

The important aspect of ensuring the paint remains food safe is through the glazing. The main consideration is to completely glaze the ware so that the entire body is sealed and none of the paint or raw pottery is exposed to foodstuff or wear and tear.

Select the correct glaze for your project

When considering the glaze for your food safe pottery, you need to ensure that the glaze is insoluble. Many foods contain high levels of acid such as tomatoes and vinegar and are likely to dissolve weak glaze.

It is best to choose an acid resistant glaze, which has been extensively tested to ensure its suitability for food safe products. Although lead free glazes are safe for food, they are not always suitable to resist certain types of food.

You should also try to avoid any special finishes such as cracked, matte or speciality, as they are not guaranteed to be food safe.

In general terms, it’s best to use glazes that have not only been tested for stability but also do not include any toxic materials - in that way, you know that even if your project doesn’t quite go to plan then you are not using anything toxic. A stable glaze ensures durability and a robustness that is required for continuous washing and use.

Also, less important, but equally required for consideration is the necessity for food safe pottery to resist abrasion from cutlery. Not only does the scraping sound become an annoyance but also visible bits of metal residue can be left behind. To avoid these issues, steer clear of matte glazes for food safe pottery.

Firing your food safe pottery

To ensure that your pottery is hardened sufficiently and that your glaze has encompassed your entire project, it is important that your food safe ceramic ware is fired properly and consistently. Using an electric kiln, with a programmable element, will ensure that you achieve a consistent temperature and the wares can be left within the kiln for the optimum time.

Soul Ceramics offers a range of electric powered kilns, all of which are suited to creating food safe pottery and ensuring consistent end products. Please see our full range here.

Testing your pottery for food safety

There are a couple of really simple methods for testing the robustness and suitability of your food safe ceramics.

The first is to squeeze some lemon juice on a glazed area of your project and then place the rest of the lemon on to the ware, leaving it overnight. The next morning, remove the lemon and rinse the ware; if the color of the glaze has changed then this indicates that the glaze is not sufficient for foodstuffs. 

The second test is to test your work in a microwave. Fill your ware with water and place in the microwave for 1 minute. If the glaze is insufficient then the ware will absorb the water and the work will become very hot. The water may also cause cracking of the glaze if it is not sufficient.

Ultimately, there are a number of elements that add up to a food safe ceramic piece. Glaze is perhaps the key element as this ensures that not only does the food not come in contact with any potential harmful substances, but also ensures that the ceramic ware is robust, lasts for a long time and ultimately is suitable for its intended purpose.

If you would like any advice on how to fire food safe ceramics, then please contact Soul Ceramics and our expert team will be happy to give you some advice on the kiln you should be using to fire your project.

Additional resources on pottery

• How to make pottery at home
• Pottery For Kids
• A mini guide to starting your own pottery business
• How to use a slump mold for pottery