Everybody loves beautifully served dinners in handcrafted dishware as they add a touch to the meals and make the particular dish entirely amazing. But is the food that you are eating served in pottery materials safe? You have to take a deep insight into the same. In recent times, potters and other small manufacturers are now aware that pottery or ceramics are not as pure as they used to be earlier. All these come with potential health impacts that may harm a user in any manner. Though people from the same field are aware of the facts or the risks, when it comes to a common man, you would think about what food-safe pottery glazes are.
Every potter tries to use the safest pottery glaze that can stand out in every usual kitchen. Alluring glazed pottery involves several variables like temperature, availability of various chemicals, inorganic and organic materials, a variation of the kiln, etc. Now, it is quite challenging to know whether the glazed pottery you are using is truly safe or not.
Here in this article, we will be talking about the different aspects of food-safe glazes and how to test if a glaze is food-safe or not. So, without much ado, let’s proceed.
Which Elements Make the Glazed Pottery Food-safe?
Many glazed pottery products have a high content of poisonous lead particles. Also, the quantity of lead residues or other heavy metals that are filtered when the surface of the glaze is disturbed decides whether it is food safe or not. Food safety is never the same as non-toxicity. It is so because; non-toxicity refers to a product in its unfired state. A container is food safe only when a glaze consists of lead as well as cadmium, yet it is fired.
Clay and other materials that exist naturally help in crafting pottery. So, before having food in the pottery dishes, you need to be cautious about safety than being sorry later. The United States Food and Drug Administration (FDA) traces the particular quantity of cadmium and lead in the pottery which guarantees a specific piece is lead and cadmium safe. Leaching helps to identify if dishware is food-safe.
All of us aim to craft designer crockeries, but mostly ignore the health factors related to making food-safe crockery. So, if you are ready to take the design choice on your part then, get ready to take responsibility for this matter too. If you calculate the oxide formula of the glaze and perform several tests, then you will be in the right position to defend yourself from using unsafe pottery wares.
Food-safe Glaze Tests:
If you love pottery items or use glazed pottery products daily, then it is essential to check the safety and durability of your product. Testing the glazed pottery item is vital because health can never be compromised. Performing food-safe glaze tests at laboratories will cost you a fee, or sometimes this fee can exceed your pocket.
There are some tests that you can perform at your home and can check whether your glazed pottery is food-safe or appropriate for you.
To make sure that you do not regret it later, we have listed down a few tests that you can perform at your home with ease.
Test |
Procedure |
Lemon Test |
Pour the lemon juice into the glazed pottery and leave it out overnight. The next morning, remove the lemon juice. The variation in the color of glazed pottery indicates the presence of strong acid in the product. If you are using glazed pottery without this test, then the acid present in it can harm you. |
Vinegar Test |
Dip the glazed pottery in vinegar and leave it untouched for one day. If the color of your glazed pottery starts fading, it indicates that the glazed pottery product is not food-safe. It contains hazardous materials that can affect your health. |
Microwave Test |
Fill the glazed pottery product with water and keep it in the microwave for 1-2 minutes. If the clay body absorbs the water and becomes hot, then the glazed pottery ware is not food-safe. The absorption of water indicates the presence of weak bonds of clay and glaze that can chip off at any time. |
Dishwasher Test |
Keep your glazed pottery in the dishwasher for some time, and then compare the surface of the ware before keeping it in the dishwasher. You can also use two identical glazed pottery products to get good and clear results. If the one put in the dishwasher looks different in color, glossiness, or texture, then the glazed pottery ware is not food-safe. |
Proper Melting of Glazes: A Key Factor for Ensuring Food-Safety
Being an ordinary human being, you will be thinking glazes are indestructible components. Almost all glazes undergo leaching at some point in time when they come in contact with water. The effect of leaching is way great when they come in contact with hot acids. If the glaze is made using harmless materials like silica, dolomite, whiting, ball clay, etc., then leaching is just an aesthetic issue. But if the same glazing employs some metallic colorants or minerals like lead, chrome, lithium, etc., then safety becomes a concern.
The glaze, when not appropriately melted, is somewhat non-resistant to leaching. A glossy glaze helps in identifying if the degree of melt was up to the mark; however, it is hard to tell if a matte-finished glaze is developed correctly or not.
How does the Liner Glaze make the Glazed Pottery Food safe?
Using a liner glaze is an easy and impressive way to assure that your glazed pottery has a leach-resistant surface. It also ensures that the glazed pottery is durable and has a high tangible strength to hold the bonds of glaze and clay. Every food-safe glaze has a fantastic glossy, transparent or translucent glaze layer, known as a liner glaze. It is done to eliminate the risk of releasing metallic colorants to food or drink while you are using that glazed pottery. They are applied to glazed pottery with a variety of methods and techniques.
Before applying the liner glaze, you have to understand the fluidity and melting point of the glazed pottery. The only purpose of applying liner glaze on the glazed pottery is to ensure food safety. So, it is highly recommended to use liner glaze such as Mayco Designer Liner.
How Does Crazing of Glazes Affect the Food-Safety?
If the surface of the glazed pottery is soft and porous, then it will reduce the safety of your health. If your glazed pottery is crazed, then it is inviting bacterial infections and creating a breeding ground for bacteria, which will decrease the safety of food items kept in that ware. Crazing can also create troubles like filling the glazed pottery product with moisture to break the bonds of the glazing compounds and clay elements, which in turn will increase the risk of mixing harsh acids with your food.
You can keep a check on crazing by keeping the glazed pottery product in the microwave. If it soaks water, then the ware is not food-safe. Crazing practically weakens the glazed pottery product and reduces its strength and food safety. It attacks the quality of your ware. If it soaks water, then the ware is not food-safe. Crazing practically weakens the glazed pottery product and reduces its strength and food safety. It attacks the quality of your ware. If you expose the glazed pottery to high heat, then it will start crazing and contaminate the food, which is no longer safe to eat. So, before the regret, make sure you are also adopting preventive measures to retain the food safety of your glazed pottery pieces.
Things to Consider for Crafting a Food-safe Glazed Pottery:
Well, there are certain things that a potter must consider to make food-safe glazed pottery ware – some of those factors we have listed down below.
Factors |
What to Look after? |
Chip-resistance |
Always check the chip resistance of the glazed pottery ware. It ensures that the glazed pottery will not chip or rim off quickly. |
Microwave or oven safety |
Make sure that the glazed pottery product that you craft has the same temperature as your microwave. If the ware has been baked or fired at higher temperatures and you put them in a low temperature-based microwave oven, then the glazed pottery can melt, being unsafe for food consumption. |
Dishwasher-safe |
Keep an eye on the quality of glazed pottery ware. Make sure that the usual dishwasher can wash the item. |
Check the lead content |
Make sure the glaze you are using for crafting your pottery has low lead content. A high percentage of lead in the ware can cause viral health issues or food poisoning. |
Test clearance |
Before using your crafted glazed pottery, always make it go through the food-safety checking tests. If your pot passes all the tests, then you can presume the safety of the glazed pottery product. |
Tips that Can Make Your Glazed Pottery Food-safe:
Now, that you have realized the factors that you must keep in mind while crafting a pottery piece for food purposes, let’s move on to the tips. The following are given a few tips that you can adhere to for making a completely food-safe glazed pot.
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Make sure that your glazed pottery has gone through a proper firing process. It is so because firing helps in making covalent bonds between the clay and glaze, which finally results in the formation of food-safe glazed pottery.
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Use elements like silica and alumina in limited amounts, so that they do not create further problems when food is served on the dishes.
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Since the presence of oxides in the glazed pottery can destroy your ware and make it start leaching, it is vital to test it correctly.
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Do not use a large number of oxides or colorants in the glaze.
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Protect the glazed pottery from elements like Lithium, Barium, and Manganese because they are very harmful and reactive.
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Always opt for a liner glaze for your ware.
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Make sure the glaze does not melt with an increase in temperature.
What to Look for in Buying a Lead-free Glazed Pottery that is Food-safe?
Till now, we had been discussing how to ensure the food-safety property in a pottery piece crafted by you. But, the same problem of leaching and other food-safety issues may prevail in pottery ware that you buy from a shop. So, even if you buy a glazed pottery piece, you should always pay close attention to check if the item is food-safe or not.
Many consumers do not consider the following factors before buying glazed pottery and get prone to health risks. So, you being a knowledgeable artist as well as a cautious buyer, look for these random factors as they protect you and ensure your health.
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If the glazed pottery has a crude appearance or is not a regular shape, then it will give a hint of unusual firing.
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Have a good view of the texture of the glazed pottery as sometimes unsafe glazed pottery is damaged or excessively worn out.
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Always buy good-quality and safe glazed pottery from a reliable manufacturer that gives you a guarantee of the product with other details. Buying it from flea markets or small vendors must not be an option for purchasing food-safe glazed pottery.
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If the glazed pottery ware is highly decorated with bright colors like red, orange, yellow, etc., then do not buy them because bright colors use high-intensity pigments that are not good for your health.
Conclusion:
Health is everything & maintaining your health is your responsibility. Hence, choose the right food-safe glazed pottery carefully to maintain your health. Whether you are crafting glazed pottery or buying one, always make sure it’s food-safe. In case you are making your own pottery dish or plate, remember to use less pigmented glazes and fire the glazed pottery for an adequate time, as the process prevents the toxic materials from leaching out into the food served in the ceramic ware. We hope that this article will be helpful for you to make sure that the glazes you are using for pottery are food-safe.
Happy sculpting!