|
Search over 100 encyclopedias and dictionaries: |
Research categories | Follow us on Twitter |
Research categories
View all topics in the newsView all reference sources at Encyclopedia.com |
|||
lactose
lactose or milk sugar, white crystalline disaccharide (see carbohydrate ). It has the same empirical formula (C 12 H 22 O 11 ) as sucrose (cane sugar) and maltose but differs from both in structure (see isomer ). It yields the simple sugars D-glucose and D-galactose on hydrolysis , which is catalyzed by lactase, an enzyme found in gastric juice. People who lack this enzyme after childhood cannot digest milk and are said to be lactose intolerant. Lactose is formed in the mammary glands of all lactating animals and is present in their milk. It is produced commercially as a byproduct of milk processing. When milk sours, the lactose in it is converted by bacteria to lactic acid. Lactose is less sweet-tasting than sucrose and is not found in plants. |
|
|
Cite this article
"lactose." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "lactose." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1E1-lactose.html "lactose." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-lactose.html |
|
lactose
lactose The carbohydrate of milk, sometimes called milk sugar. A disaccharide of glucose and galactose. Used pharmaceutically as a tablet filler and as a medium for growth of micro‐organisms. The fermentation of lactose to lactic acid by bacteria is responsible for the souring of milk. Ordinary lactose is α‐lactose, which is 16% as sweet as sucrose; if crystallized above 93 °C, it is converted to the β‐form which is more soluble and sweeter.
|
|
|
Cite this article
DAVID A. BENDER. "lactose." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. DAVID A. BENDER. "lactose." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O39-lactose.html DAVID A. BENDER. "lactose." A Dictionary of Food and Nutrition. 2005. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-lactose.html |
|
lactose
lactose (milk sugar) Disaccharide present in milk, made up of a molecule of glucose linked to a molecule of galactose. It is important in cheesemaking, when lactic bacteria turn it into lactic acid. This sours the milk and results in the production of cheese curd.
|
|
|
Cite this article
"lactose." World Encyclopedia. 2005. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "lactose." World Encyclopedia. 2005. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O142-lactose.html "lactose." World Encyclopedia. 2005. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-lactose.html |
|
lactose
lactose (milk sugar) A sugar comprising one glucose molecule linked to a galactose molecule. Lactose is manufactured by the mammary gland and occurs only in milk. For example, cows' milk contains about 4.7% lactose. It is less sweet than sucrose (cane sugar).
|
|
|
Cite this article
"lactose." A Dictionary of Biology. 2004. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "lactose." A Dictionary of Biology. 2004. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O6-lactose.html "lactose." A Dictionary of Biology. 2004. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-lactose.html |
|
lactose
lactose (milk sugar) (lak-tohz) n. a sugar, consisting of one molecule of glucose and one of galactose, found only in milk. l. intolerance inability to absorb lactose, caused by absence or low activity of the enzyme lactase.
|
|
|
Cite this article
"lactose." A Dictionary of Nursing. 2008. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "lactose." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O62-lactose.html "lactose." A Dictionary of Nursing. 2008. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-lactose.html |
|
lactose
lac·tose / ˈlakˌtōs; -ˌtōz/ • n. Chem. a sugar present in milk. It is a disaccharide containing glucose and galactose units. |
|
|
Cite this article
"lactose." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "lactose." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O999-lactose.html "lactose." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-lactose.html |
|
lactose
|
|
|
Cite this article
MICHAEL ALLABY. "lactose." A Dictionary of Zoology. 1999. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "lactose." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O8-lactose.html MICHAEL ALLABY. "lactose." A Dictionary of Zoology. 1999. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-lactose.html |
|
lactose
lactose •adiós, chausses, Close, Davos, dose, engross, gross, Grosz, jocose, morose, Rhos, verbose
•grandiose • religiose • otiose
•globose • viscose • bellicose • varicose
•vorticose • cellulose • lachrymose
•lactose • comatose • siliquose
|
|
|
Cite this article
"lactose." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "lactose." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O233-lactose.html "lactose." Oxford Dictionary of Rhymes. 2007. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-lactose.html |
|
|
Search over 100 encyclopedias and dictionaries:
HighBeam™ Research, Inc. © Copyright 2012. All rights reserved.
The Encyclopedia.com advertising network includes:
