Is it useful to use hot water to scald dishes?

Source: People's Daily Science Popularization

When dining out, many friends will use hot water to scald the tableware, thinking that this can be disinfected and sterilized, and it is more hygienic to use. Can hot water really sterilize and sterilize tableware? How to make tableware cleaner? Today we will talk about tableware hygiene.

01

Can hot water scalding tableware be sterilized and sterilized?

Let's talk about the answer first: it has a little effect but is not big, and it is difficult to achieve the purpose of thorough disinfection and sterilization.

Modern people are very busy, and when they eat out, they will inevitably pay more attention to the hygiene of the tableware in the restaurant. According to the provisions of GB 14934-2016 Disinfection of Tableware (Drinking), the main microbial testing items in tableware are Escherichia coli and Salmonella, which are not detectable.

(1) Escherichia coli

Coliform bacteria are used as an important indicator to determine whether food is contaminated with feces, reflecting the possibility and degree of contamination of food by human or animal intestinal bacteria.

When the coliform bacteria in food are heavily contaminated, there is an increased chance of contamination with pathogenic bacteria in the intestine (such as Salella, Shigella, Staphylococcus aureus and enteroviruses, etc.), which is potentially dangerous to humans and animals. The use of utensils contaminated with pathogenic E. coli may cause symptoms such as abdominal pain, diarrhea, nausea and vomiting, and blood in the stool. If you want to destroy E. coli, you need to meet the condition that the temperature is above 75°C and the time is up to 1 minute before it can be killed.

(2) Salmonella

Salmonella infection can lead to abdominal pain, diarrhea, vomiting and death. However, Salmonella is not heat-tolerant and will die immediately when heated at 100°C. If the heating temperature is low, the heating time should be extended, when the temperature is 70°C, it needs to be heated for 5 minutes, if it is only 60°C, it will take 15 minutes to destroy Salmonella.

When we eat in a restaurant, the water provided by the waiter may not be boiled, and in order to avoid scalding consumers, it may be less than 60°C. When used to rinse dishes, the temperature will drop further, which cannot play a role in disinfection and sterilization.

The Consumer Protection Committee of a city once took the stainless steel tableware, self-sterilizing tableware, and centralized disinfection tableware of restaurants as experimental objects, and after artificially polluting them, through the detection of coliform bacteria and salmonella items, compared the bacterial residues of the tableware after hot water at different temperatures and after boiling for different times.

The results showed that if the tableware was scalded with water at 100°C for more than 30 seconds, the effect on removing bacteria on the tableware was quite obvious, but if the tableware was rinsed with water below 60°C, the effect was very weak.

Therefore, regarding the matter of scalding dishes with hot water, if you can ensure that it is freshly boiled 100°C hot water, blanching the tableware for 30 seconds still has some effect, which can effectively remove some bacteria.

To sum up, there is no harm in scalding the dishes with hot water when dining out, but don't expect to have obvious disinfection and sterilization effects. If the water is not hot enough and not long enough, hot water scalding dishes is basically useless. But if you want to eat safely and securely, you still have to choose a clean and hygienic restaurant.

02

How to ensure food hygiene when eating out?

Compared with whether hot water rinsing tableware can be disinfected, some friends may be more concerned about how to ensure food safety when dining out, which gives you 3 suggestions.

(1) Choose a regular restaurant

The hygiene of regular restaurants is more guaranteed, and the tableware hygiene pass rate is higher.

(2) Bring your own cutlery

If you need to eat out every day and are worried about the hygiene of the tableware in the restaurant, it is better to bring your own utensils.

(3) Identify whether the sterilized tableware is qualified

The tableware in many restaurants is packaged, and you can carefully observe whether the plastic sealing film is clean and complete before use, and whether the manufacturer's address, contact number, and shelf life are clearly marked on the package. Whether the surface of the tableware is smooth and clean, there shall be no attachments, no impurities, no oil stains, no foam, and no peculiar smell.

03

How to ensure the hygiene of your own tableware?

We should not only worry about the hygiene of the tableware in the restaurant outside, but also the hygiene of the utensils and utensils in our own kitchen. There are five main points.

(1) Regular disinfection of tableware

Regularly disinfect rice bowls, plates, spoons, etc., such as boiling disinfection, steam disinfection, and disinfection cabinet disinfection. If steam or boiling is used for disinfection, it should be kept in steam or boiling water for more than 10 minutes, and if infrared disinfection cabinet is used, it should be used according to the instructions, and the disinfection cabinet should be opened for more than 10 minutes.

(2) Replace chopsticks regularly

Most of the chopsticks used in the home are bamboo chopsticks or wooden chopsticks, if the environment is humid and not cleaned thoroughly, it is easy to breed bacteria, and even mold, long-term use will be harmful to health.

To ensure that the chopsticks are clean and hygienic, first of all, they should be carefully cleaned after each meal, and secondly, they should be dried before putting them in the cupboard, and the cupboard should be kept dry. Chopsticks should also be disinfected regularly, and bamboo and wood chopsticks can be boiled in boiling water for 20 minutes regularly or changed every 6 months.

However, wooden chopsticks are easy to deform after boiling at high temperatures, which may affect their use. If you mind, you can also choose alloy chopsticks and stainless steel chopsticks, but the stainless steel chopsticks are too slippery, and eating hot pot may also burn your mouth.

(3) Place the bowl with the mouth facing down after brushing

It is inevitable that there will be residual dishwashing water inside after brushing the bowl, and it is best to put the bowl upside down.

(4) Hang the cutting board to dry

When using a cutting board, you should first separate raw and cooked meat, and do not use the same cutting board for cutting raw meat and vegetables, or do not use the same side to avoid cross-contamination. Secondly, after using the cutting board, it should be hung to dry in time to avoid mold.

In the case of cleaning cutting boards, studies have compared the cleaning effects of different cleaning methods on different materials contaminated with E. coli. The results showed that no matter what material the cutting board was, the best cleaning effect was to use hot water above 50°C to clean the cutting board, followed by wet wiping and dish soap, and dry wiping had the worst effect.

Therefore, when cleaning the cutting board, it is recommended to rinse it with hot water above 50°C, not just dry wipe.

(5) Do not wipe the dishes with a dishcloth

Some people have the habit of wiping the dishes with a dishcloth after washing the dishes, but it's best not to do this. Because the dishcloth is really not clean, the "White Paper on China's Household Kitchen Hygiene Survey" shows that the total number of bacteria in a single piece of dishcloth collected through the activity is as high as 500 billion, and the longer it is used, the more bacteria will be. It contains 19 kinds of pathogenic bacteria, including Escherichia coli, Staphylococcus aureus, Candida albicans, Salmonella, etc.

Therefore, in order to ensure hygiene and safety, the dishcloth must be washed and dried after use, and boiled in boiling water for more than 10 minutes regularly, and the new rag should be replaced frequently.

All in all, the ritual sense of "hot water scalding tableware" can have, if you want to disinfect and sterilize the tableware, you need 100 °C water, and keep rinsing for more than 30 seconds, otherwise it will not have much effect. Also, don't just stare at the outside utensils, but also pay attention to hygiene in your own kitchen.

Author: Xue Qingxin, one of the first nutrition instructors of the National Health Commission and a registered dietitian in China

Review: Ruan Quang Feng, Deputy Director of Kexin Food and Health Information Exchange Center

Source: People's Daily Online, Science Popularization Comprehensive Science China, Xinhuanet