Can I use a notched, cracked bowl? How to choose ceramic tableware

Today's ceramic tableware costs hundreds of thousands of yuan. Once the bump creates a gap, will continued use cause adverse effects on human health?

Sample: RMB 10 to RMB 39.8

According to reports, the samples of this comparative test were provided by the staff of the Consumer Rights Protection Committee as ordinary consumers in major supermarkets (Yonghui, Wal-Mart, Lotus Lotus, New Century, China Resources Wan) Home, Xinguang Tiandi Department Store), farmers market and Taobao flagship store. The birthday bowl is custom-made by the staff of the Consumer Council as ordinary consumers. Crack and notch bowls were collected from consumers' homes.

Samples were collected from 13 ceramic tableware of Hongye, Jiayu, Minyang, Guanfu, Yachengde, Gardner, An Weina, Porcelain Dishware, and Japanese-made good-yaki, auspicious and other brands. Main producing areas: Tangshan, Hebei, Jingdezhen, Jiangxi, Dehua, Fujian, Zhuzhou, Hunan, Chaozhou, Guangzhou, Shenzhen. Samples (except earthen bowls and shou bowls) have the highest price of 39.8 yuan and the lowest of 2.9 yuan, of which 7 are below 10 yuan and 6 are above 10 yuan.

Xu Jing, Secretary General of Municipal Consumers Committee, introduced the thermal shock resistance, microwave oven adaptability, refrigerator-to-microwave oven adaptability, refrigerator-to-oven oven adaptability, water absorption, and heavy metal migration under various conditions. Indicators (lead, cadmium, chromium, arsenic, antimony, nickel), coliforms and salmonella were tested.

Result: Bacteria in cracked and cracked bowls exceeded standards

After testing, the thermal shock resistance, microwave oven adaptability, refrigerator-to-microwave oven adaptability, refrigerator-to-oven adaptability, water absorption, and heavy metal migration of the 13 ceramic tableware basically met the requirements.

In particular, thermal shock resistance is a characteristic indicator that shows that ceramic products do not show cracks or no damage when they resist sudden changes in external temperature. The sample is heated to 180 ° C and held for 30 minutes, then placed in a 20 ° C flowing water tank for 10 minutes to see if the surface of the sample is cracked. As a result, there were no abnormalities in the other samples except 3 cracks in the bowl.

Water absorption is an important indicator of the density of ceramic container products for food. After the ceramic container with high water absorption rate absorbs water, the glazed surface of the ceramic container may be cracked due to excessive expansion. At the same time, its anti-pollution ability is also weak. Because the surface of the clay bowl is unglazed, the water absorption rate is 2.66%.

In the test of heavy metal migration, four modes such as 4% acetic acid solution soaking at 100 ° C for 15 minutes; 70% ethanol solution soaking at room temperature for 24 hours; soy sauce at room temperature for 24 hours; boiling vegetable oil at room temperature for 24 hours were used. The results show that there is no significant difference between expensive imported ceramic tableware and domestic brand ceramics, and a small amount of heavy metals are precipitated, but within the safe value.

However, it is worth noting that the coliform and salmonella performance in the chipped and cracked bowls was not satisfactory. When the sample is filled with the same meals, it is placed in the same room temperature environment for 24 hours. After 24 hours, it is simulated to wash at home, and then tested for microorganisms according to standards. As a result of the test, coliforms were detected in a set of brand bowls and a set of longevity bowl samples, while coliform bacteria were detected in all cracked and chipped bowls, and even a group of samples detected Salmonella.

Buying: Try to avoid glazed ceramic tableware

Xu Jing suggested that, when choosing ceramic tableware, try not to use glazed decoration, especially the inner wall of ceramic tableware should not be painted. For glazed porcelain, it is easy to identify by visual inspection and hand touch. Those who are less bright than the glazed surface, feel less smooth, or even have raised edges on the screen should be cautiously purchased. Don't add patterns and text to the bowl when making the bowl.

At the same time, the ceramic tableware you bought should be soaked with vinegar and 10 times water for 2-3 hours and then boiled. This will precipitate toxic heavy metals and reduce the potential harm of ceramic tableware to the human body.

In addition, try not to use ceramic tableware for a long time to store acid foods and beverages such as fruit juice, wine, coffee, etc. to reduce the precipitation of heavy metals. When there are gaps or cracks, discard them in time.