From left: Kefir grain surface at a progressively increasing magnification. Large cells are yeasts and small cells are bacteria |
Kefir is a cultured milk beverage, the result of microbial action of a wide community of micro-organisms present in kefir grains on milk.
The micro-organism (bacteria and yeast cells) are located on the surface of the grains as shown in the row above and are also lodged in the grains which are composed of a polysaccharide matrix of "kefiran" (image at left). The micro-organisms metabolize lactose present in the milk and produce lactic acid which coagulates the milk and forms a beverage called kefir. It has a uniform creamy consistency and is slightly acidic mostly from lactic acid. Some effervescence is caused by carbon dioxide and a minute (<2%) concentration of alcohol due to the action of yeast cells also present in the grains.
There are many aspects of kefir featured on the Internet, from the origin of kefir in the
Caucasus mountains, what it is, to information on how to make kefir at home and other aspects, including science and such scientific questions aas to whether the quality of kefir is affected by rinsing the kefir grains with water.
For information on microscopy, please contact the author.
Updated: April 25, 2013 ©SCIMAT 2013 |