It is often considered as a healthy method of cooking because it does not use fat to cook or flavor the food. However, poaching can lead to the trivial production of mutagenic agents, the effects of which are not fully understood.
https://en.wikipedia.org/wiki/Poaching_(cooking)
Poaching is not boiling -- boiling is a more aggressive way of cooking. The liquid should be at a very low simmer, just high enough for bubbles to barely break through the surface. The French word for this is Frissonne, meaning that the liquid should be just hot enough to make the surface of it shiver.
http://www.cooksinfo.com/poaching
Poaching is differentiated from the other moist heat cooking methods, such as simmering and boiling, in that it uses a relatively low temperature (about 160–180 °F (71–82 °C)).
https://en.wikipedia.org/wiki/Poaching_(cooking)
Poaching is cooking in a gently-heated liquid. The liquid protects what you are cooking from being exposed to high heat. Most people think immediately of Poaching eggs in water, but the process was actually perfected by the French to cook fish or poultry. The liquid can be water, stock or wine. Some people say that Poaching in a flavourful stock adds flavour to the item; other people would counter that the flavourful stock replaces flavour that is leeched out, and they're both right.
http://www.cooksinfo.com/poaching
It is also used to rapidly raise the temperature of foods, as with blanching. Poaching itself is part of a family of moist-heat cooking methods but separates itself in that it is primarily for delicate foods such as eggs.
https://en.wikipedia.org/wiki/Poaching_(cooking)
This moist-heat cooking method uses a sautoir or other shallow cooking vessel, heat is transferred by conduction from the pan, to the liquid, to the food. Shallow Poaching is best suited for boneless, naturally tender, single serving size, sliced or diced pieces of meat, poultry or fish.
https://en.wikipedia.org/wiki/Poaching_(cooking)
The key to poaching meats and proteins is to make sure that your stove temperature is not too high and that your liquid does not come to a boil, as this will cause the meat to break down, resulting in a greasy meal in which the fats are no longer separated on the top of the liquid.
http://dairyfreecooking.about.com/od/dairyfreeglossary/g/poaching.htm
Chicken thighs shallow-poaching in a pan. Poaching is a type of moist-heat cooking technique that involves cooking by submerging foodstuff in a liquid, such as water, milk, stock or wine.
https://en.wikipedia.org/wiki/Poaching_(cooking)
Definition: Poaching is an incredibly versatile cooking method; just about everything from fruits to meats can be cooked using this technique. Poaching is merely simmering food in liquid until it is cooked through.
http://dairyfreecooking.about.com/od/dairyfreeglossary/g/poaching.htm
When Poaching fruit, usually a sweetened liquid is used, either a sugar syrup or wine with sugar added. Poaching is a useful way of cooking delicate items such as fish, seafood or fruit. The food doesn't get tossed about a lot, so there is a greater chance of its staying intact for good presentation.
http://www.cooksinfo.com/poaching
what is poaching food
Poaching is cooking in a gently-heated liquid.