Ice cream man. (Food chemistry: states of matter).
The good news for ice cream lovers? Goff has discovered an ingredient that keeps crystals tiny--and may help your ice cream stay as smooth as on the day it was made. The ingredient is a winter-wheat protein (molecule that controls cell growth, among other functions). Called AFP, or antifreeze protein, the molecule directs ice-crystal formation. "Wheat cells produce a variety of ice-modifying proteins in response to cold," says Golf. When an ice crystal forms and grows in a wheat plant, AFPs latch onto the crystal's surface, blocking further growth.
Goff inserted the proteins into a batch of ice cream in his lab, and the proteins had the same ice-modifying effect: Tiny crystals stayed tiny, even when he let the ice cream melt a little before refreezing. Normally, refreezing causes some water to leach out of the ice cream in the form of unpleasantly large ice crystals. If Goff's research continues smoothly, the world's greatest frozen dessert may soon be creamier than ever!
RELATED ARTICLE: Sweet sensation.
When a glob of vanilla ice cream hits your tongue, nerve cells (electrical fibers connected to the brain and spinal cord) detect its cool temperature and creamy texture. At the same time, your tongue's taste-receptor cells (taste buds) kick in. "Each taste bud is an onion-shaped cluster of 50 to 100 taste cells," says scientist Julie Mennella at Philadelphia's Monell Taste Laboratory. The receptor cells, which resemble orange segments, can decipher five tastes: umami (meaty), sour, salty, bitter, and sweet. When ice cream's sugar molecules bind to taste-cell proteins--molecules that can control chemical reactions--the cells secrete chemicals that ferry electrical signals to nerve cells. In turn, the nerve cells transmit the information to the brain, which interprets the message: Sweet!
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|Article Type:||Brief Article|
|Date:||May 6, 2002|
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