Alalanatha from Prague, Czech Republic asks: “Do you think it is good to cook with hot water straight from the tap? Our restaurant cooks think they can save time in this way? I have heard it may contain some dissolved metals from the pipes.”
It may save time, yes, but shorten your life, and the life of your customers. Dissolved metals are the problem, lead, in fact. And lead poisoning is quite nasty. So not really saving time at all.
Here’s some information gleaned from various sources:
“The use of lead solder to join plumbing pipes used to be common worldwide. In many places, although use of lead solder in plumbing was banned in the 80’s, older plumbing may still contain lead-soldered joints. In addition, plumbing parts made of brass contain approximately 8 percent lead. Through the corrosion of lead-containing plumbing, water can contain elevated levels of lead.
Therefore, wherever you are in the world, if you are concerned that there may be lead in your drinking water, then the simplest thing to do is to follow this advice (issued by the U.S. Environmental Protection Agency):
• Never use hot water from the tap for drinking or cooking. If you need hot water, then draw cold water from the tap and heat it on the stove.
• Only drink or cook with cold water, and let the cold water run until you notice that the water has become colder. Flushing a cold-water tap or fountain before use is especially important if it has not been operated for several hours, such as overnight.
• Remove the strainer from your tap periodically, and flush it and the tap for several minutes to remove any sediment that may have built up.
And here’s more:
“The insides of a hot water heater contain metals that can, and do corrode. Some of the pipes in your home that are not made of PVC may have lead soldering. Hot water will dissolve metals, especially lead, much quicker than cold water will.
Not to mention that over the years of daily use of drawing many litres throughout the day in cycles causes the water from the local utility, with all of it’s impurities to collect and precipitate in the bottom of the hot water heater.
This is a prime breeding ground for bacteria. Perhaps they cannot survive in an environment where the water is boiling hot, but as soon as the water cools down enough due to a power outage or extended leave (if you turn off your water heater), all the necessary nutrients are there in a nasty soup.
If you plan to cook with tap water, run the cold water for a minute or so and use that cold water for your cooking. You may want to save the ‘non-potable’ water that you flushed from the pipes as you can use it for cleaning and such.
And by all means, never draw warm water and use for infants. Since infants are developing at a rapid rate, they are much more vulnerable to the concentrations of impurities and lead and could potentially get lead poisoning from warm tap water.”
Posted by Kurma on 10/8/07; 7:41:13 AM