Tableware Basic Knowledge and Inspection Standard

The tableware can be roughly divided into three types: ceramics, glassware and knife & fork. How to inspect the tableware?

Ceramic Tableware

In the past, ceramics were considered as non-toxic tableware by public while there were poisoning reports for using the ceramic tableware. The beautiful coating (glaze) for some ceramic tableware contained lead because if the temperature for baking ceramics is insufficient or the glazing materials not conform to the standards, it will make tableware contain higher lead. When foods contacts with tableware, the lead will permeate through the glazing layer and mix with foods. Therefore, the ceramic product with the uneven glazing materials on thorny and spotted surface, even with crack, is not suitable to be used as tableware. When choosing the ceramic tableware, gently pat on ceramics with index finger. If it can give out a ringing sound like a Chimestone, it’s indicated that the ceramics body is fine. After baking, if it gives out the hoarse sound by patting, then the ceramics is broken or the quality of ceramics body is poor.

Appearance Quality Inspection

Ceramics appearance quality mainly includes the common allowable defect range, such as product surface glossiness, whiteness, color difference and specification, size, matching, patterns etc.

Glass Tableware

The glass tableware is featured as high hardness and stable chemical performance, and has the disadvantage of fragile. If using it improperly, it’s easy to result in bursting. The glass table shall be clean and neat without toxic substance but the glass tableware may “mildew” sometimes, that is because the glass is eroded by water for a long time, the sodium silicate in glass will react with carbon dioxide in the air and generate the white carbonic acid crystal, which is harmful to human health. Therefore, the alkaline detergent is used to remove it.

Before using it for the first time, the common glass tableware shall be soaked in vinegar water to dissolve out the lead. It’s better to use the common glassware to contain the acidic beverage or foods and glassware containing lead shall be avoided for using as far as possible.

Tableware Made by Other Materials

Stainless Steel Tableware

The stainless steel tableware is advantaged as elegant appearance, portability, easy to use, anti-corrosion and anti-rusting, and is popular with people. The stainless steel is made of ferrochrome mixing with nickel, molybdenum and other metals. Therefore, it’s needed to notice that do not contain salt, sauce, vinegar etc. for a long time, in which the electrolyte will react with stainless steel for long-term contact, making the hazard substance being dissolved.

Plastic Tableware

The common plastic tableware basically is made of the raw materials: polythene and polypropylene. Most of them are non-toxic plastic recognized by national health departments. It’s tested that the released lead, cadmium and other heavy metal elements in colorful pattern of partial plastic tableware are out of standard. Therefore, the patternless, colorless and odorless plastic tableware shall be chosen as far as possible.

Bamboo Tableware

The greatest advantages of bamboo tableware are convenient for transporting raw materials and no toxic effect from chemical products. However, their weakness is easy to be polluted and to mildew compared with other tableware.

Single-use Tableware

The single-use tableware refers to a kind of disposable tableware made of plastic, high foaming material, PE coated paper etc.

The tests for stainless steel tableware mainly include the following aspects: 1. Appearance: scratch, pitting, crease and pollution. 2. Special inspection: thickness tolerance, weldability, corrosion resistance, polishing performance (BQ) (pitting) are strictly prohibited during making the spoon, scoop, fork etc., because they are difficult to be removed. Those defects, including scratch, crease and pollution etc., are prohibited no matter for high-level materials or low-level materials. 3. Thickness tolerance: in general, the required thickness tolerances are different for different stainless steel products, such as Class-II tableware and vacuum cup, the thickness tolerance requirements for both of them are relatively high as -3-5%. However, the thickness tolerance requirement for Class-I tableware is -5%, the thickness tolerance requirement for steel pipe is -10%, the thickness tolerance requirement for refrigerator materials in hotel is -8% and the thickness tolerance required by the distributer is 4%~6% in general. Meanwhile, different product sales at home and abroad will lead to different requirements of client for raw material thickness tolerance. Generally, client has relatively high thickness tolerance requirement for the imported product while the domestic client has relatively low thickness tolerance requirement (considering from cost factor), even some clients required -15% for it. 4. Weldability: the requirements for welding performance vary from different product purposes. Class-I tableware has no requirement for welding performance in general, even including some pots enterprises. However, most of products require the good welding performance for raw materials, such as Class-II tableware, vacuum cup, steel pipe and water heater. 5. Corrosion resistance: most of stainless steel products require good corrosion resistance, such as Class-I and Class-II tableware, cooking utensil, water heater, water dispenser etc. Some foreign merchants may conduct corrosion resistance test for products: heat the NACL solution to boiling, dump the solution after a period of time, wash and dry it, weigh the weight loss to determine the corrosion degree (note: when polishing the product, due to abrasive cloth or abrasive paper containing Fe, it will lead to rusty spot on the surface when testing.) 6. Polishing performance (BQ): at present, stainless steel products will go through the polishing process when producing. Only a few products, such as water heater, water dispenser liner and others do not need the polishing. Therefore, it’s required high polishing performance for raw material. 


Post time: Jan-12-2022