Taste and odor

Water can dissolve many different substances, giving it varying tastes and odors. Humans and other animals have developed senses that enable them to evaluate the potability of water by avoiding water that is too salty or putrid. The taste of spring water and mineral water, often advertised in marketing of consumer products, derives from the minerals dissolved in it. However, pure H2O is tasteless and odorless. The advertised purity of spring and mineral water refers to absence of toxins, pollutants and microbes, not the absence of naturally occurring minerals. Traditionally, mineral waters were used or consumed at their spring sources, often referred to as "taking the waters" or "taking the cure," at developed cities such as spas, baths or wells. The term spa was used for a place where the water was consumed and bathed in; bath where the water was used primarily for bathing, therapeutics, or recreation; and well where the water was to be consumed. Active tourist centres have grown up around many mineral water sites since ancient times, such as Hungary, Hisarya (Bulgaria), Bilina (Czech Republic), Vichy (France), Jermuk (Armenia), Yessentuki (Russia), Spa (Belgium), Krynica-Zdroj (Poland), Sulphur Baths (Tbilisi, Republic of Georgia), Bath (England), or Karlovy Vary (Czech Republic), Myrhorods'ka (Ukraine). In Romania, a country enjoying a privileged position as home to over one-third[1][2] of the European mineral and thermal springs, resorts developed since antiquity in places such as Baile Herculane, Geoagiu or Slanic. Tourist development resulted in spa towns and hydropathic hotels (often shortened to "hydros"). In modern times, it is far more common for mineral waters to be bottled at the source for distributed consumption. Travelling to the mineral water site for direct access to the water is now uncommon, and in many cases not possible (because of exclusive commercial ownership rights). There are more than 3,000 brands of mineral water commercially available worldwide.[3] The more calcium and magnesium ions are dissolved in water, the harder it is said to be; water with few dissolved calcium and magnesium ions is described as being soft.[4] The U.S. Food and Drug Administration classifies mineral water as water containing at least 250 parts per million total dissolved solids (TDS), originating from a geologically and physically protected underground water source. No minerals may be added to this water.[5] However, in many places, the term "mineral water" is colloquially used to mean any bottled carbonated water or soda water, as opposed to tap water. Carbonated water (also known as club soda, soda water, sparkling water, seltzer water, or fizzy water) is water into which carbon dioxide gas under pressure has been dissolved, a process that causes the water to become effervescent. Carbonated water is the defining ingredient of carbonated soft drinks. The process of dissolving carbon dioxide in water is called carbonation.