The term ‘water quality’ is used to refer to the physical, chemical and biological characteristics of water. Parameters of water quality are a measure of the condition of water relative to the requirements of one or more biotic species and/or to any human need or purpose. It is most frequently used by reference to a set of standards against which compliance can be assessed. The most common standards used to assess water quality relate to health of ecosystems, safety of human contact and drinking water.

The Indian Standards: Water for Food Processing Industry (IS: 4251; 1967 Reaffirmed 2004) specifies that the water should comply with bacteriological, physical, chemical and radioactivity tolerance limits. The various other parameters that the water has to comply with include pH, color, odour, taste, turbidity, total dissolved solids. General chemical parameters include ammonia nitrogen, anionic surface active agents, total hardness, alkalinity, residual free chlorine & chloramines, various metallic and non-metal ions, total solids and mineral oil. The water has to be tested for toxic substances such as pesticide residues, polychlorinated biphenyls and polyaromatic hydrocarbons. The various testing methods used for water for food processing include standard plate count, proteolytic plate count, lipolytic plate count, test for coliform bacteria etc.