Differentiate types of drinking water products

KHANH NAM (write)

Every day the human body needs to add at least 1.5 liters of water through the diet. To protect health, drinking water must meet hygiene standards. Reporters of Can Tho Newspaper had an interview with Mr. Dam Hong Hai, Food Hygiene and Safety Inspector, Can Tho Department of Health on distinguishing drinks and how to choose drinking water.

Country includes the following forms:

- Tap water: It is a water system that has been treated to settle, filter, and sterilize. In some advanced countries, due to the modern water treatment system, this water source can be drunk at the tap without worrying about any threat. However, in most developing countries, including Vietnam, tap water only meets clean standards for domestic use such as bathing, washing, food processing . so it is impossible to drink directly.

- Mineral water (Mineral water): This is the type of water on the market called spring water. This type of water is distinguished from other ordinary drinking water by: having a certain amount of mineral salts with their ratio of correlation and the presence of directly exploited trace elements or other components. from natural spring water sources or groundwater. Mineral water exists in two forms:

(Photo: Yoursdaily)

+ Natural mineral water with natural gas: is a natural mineral water after bottling still contains the content of carbon dioxide (CO ₂ ) at the water source.

+ Non-carbonated natural mineral water: is natural mineral water after bottling free CO2 in excess of the necessary content to keep dissolved carbonate salts in water. - Purified water: Is The water is purified through filtration, sterilization, bottleless. Depending on the source of raw water supplied (tap water, well water) people will have their own treatment method.For example , water from wells can present organic matter, inorganic substances, especially iron, manganese, nitrate, heavy metals such as arsenic, lead . so people have to eliminate by Water softening (for hard water), redox, before going to the next step of settling, filtration and sterilization. If the water source is tap water, the raw filter is less complicated and less expensive.

However, for bottling and distributing to consumers, this water source must go through raw filtration, ion exchange, activated carbon filtration (effective for deodorizing), fine filtration (by reverse osmosis method). ), disinfection via ozone and ultraviolet rays . then bottling.

* Current mineral water and purified water are sold in parallel with the market at a price not much different. How are the quality of these two types of water different?

- In principle, both of these types of water are clean and relatively sterilized (there are many products that do not meet the standards of sterilization), but the difference is in the chemical composition. Mineral water contains certain levels of soluble mineral compounds that are beneficial for health such as: Calci, magne, phosphore, zinc, selenium, cobalt, manganese, sodium . Meanwhile, pure water (main call corpse is filtered water), very ' poor ' trace minerals. On the sensory side, drinking mineral water tastes more ' delicious ' (due to mineral salts) and is cool (due to CO _{2 content} ). Mineral water is valuable for health, especially for children, the elderly, pregnant women, sports players . Especially, women use mineral water to help skin health.

However, attention should be paid to subjects with renal impairment, hypertension, neurological syndrome, and should limit mineral water use. Studies suggest that the use of regular purified water (ie, eliminating micro-mineral components) is not good for health, not to mention buying it for fake pure water.

* What about water through the filter?

- On the market there are many types of filters such as filter columns, filters. In general, this water source ensures physical and chemical properties (deodorizing, tasteless, no toxic, total residue). However, the ability to remove microorganisms (bacteria and viruses) only reaches a relative level of 90-98%, depending on the membrane size and the effectiveness of sterilization. There are several types of filters that are unable to filter viruses (while boiled water for 15 minutes will kill 100% of bacteria and viruses). In addition, during use, when the filter and filter column have been damaged, or inert due to the biofilm has been disabled, the filtering efficiency will be significantly reduced . So when buying filter , need to check carefully the structure and performance, as well as the storage conditions of the filter .