JCE Online Journal of Chemical Education
 | Subscriptions  | Software Orders  | Support  | Contributors  | Advertisers  | 

JCE Print
   Current Issue
 Previous Issues
 Supplements
 Search JCE Index

JCE Digital Library
   JCEDLib Catalogue
   ChemInfo
 Data-Driven Exercises
 DigiDemos
 Featured Molecules
 LivTexts
 LrnCom
 QBank
 SymMath
 WebWare

JCE Software
   Latest Releases
 Software & Video
 Downloads
 Support

Only@JCE Online
   JCE Online Store
 JCE HS CLIC
 JCE Discussion Forums
   Biographical Snapshots
 ChemEd Resource Shelf
 Featured Molecules
 Hal's Picks
 Project Chemlab
 Reviewed WWW Sites
 "Web-Ed" Articles

About JCE
   Features
 Publications
 Operations
 Outreach
 Contact Us


  Home > JCE Print > Journal of Chemical Education > Issues > 1998  > March  >
Chemistry Everyday for Everyone
Tested Demonstrations
Detection of Catalysis by Taste
Robert M. Richman
Mount St. Mary's College, Department of Science, Emmitsburg, MD 21727-7799
Cover
March 1998
Vol. 75 No. 3
p. 315
Abstract
A classroom demonstration is outlined to illustrate by taste the large effect that a small quantity of catalyst can have. The enzyme lactase, obtained from the over-the-counter product Lactaid, catalyzes the hydrolysis of the disaccharide lactose into D-glucose and D-galactose, its monosaccharide constituents. These products have a combined sweetening power of about 0.8 relative to sucrose. The sweetness can be easily discerned in milk that has been treated with Lactaid. It is readily apparent that the Lactaid itself is not the source of sweetness, since it is a rather tasteless substance that is diluted in milk by a factor of roughly 4000 to 1. It is estimated that each lactase molecule hydrolyzes 105 lactose molecules.
More Information
*  Citation
 Richman, Robert M. J. Chem. Educ. 1998 75 315.
*  Keywords
 Demonstrations, Catalysis, Enzymes, Food Science, Biochemistry
*  History
 Created:
Last Updated:		 June 28, 1999
June 23, 2005
<< Previous Article Table of Contents Next Article >>
  Home > JCE Print > Journal of Chemical Education > Issues > 1998 > March > Page 315



Chemistry Teacher Connection

The "Chemistry Teacher Connection" (CTC) is especially for high school chemistry teachers. For only $40/year, it offers an online-only subscription to CLIC along with membership in the Division of Chemical Education, normally $65/year. CTC subscribers receive access to all articles and supplements from 1996 through the current issue.
More About CTC
Order the Chemistry Teacher Connection

C&EN CLICs

Through special arrangement with the ACS, JCE High School CLIC is now able to provide subscribers with online access to Chemical & Engineering News articles that have been selected specifically for secondary science instructors and their students. 
 C&EN CLICs

JCE Collections Available
Occasionally, collections of JCE back issues become available for donation to individual teachers, schools, or libraries. JCE matches collections with interested recipients. Recipients pay shipping costs or pick up the collection.
 List of available collections

Contributions Welcome
JCE welcomes your submission
 Contributors's Corner

Subscriptions
 Subscription Info
 Order Forms

Fishing for New Ideas
Always in the
process of
improving, CLIC
welcomes ideas and comments.

Email Us

Comments to
jceonline@chem.wisc.edu		 Copyright © Division of Chemical Education, Inc., American Chemical Society.
All rights reserved.