Why can you smell hot food from far away but not cold food?

Hello.


"Why does food smell stronger when heated?

Aroma of food is mainly due to the volatile components in them. For
example, lactones and sulphur containing compounds, including
sulphides, mercaptans, and cyclic compounds such as pyrazine, are
thought to make important contributions to the flavour of cooked
meats. Volatile carbonyls are responsible for the "chickeny" aroma of
cooked poultry. When food is heated, some of these volatile components
are released and thus make the food smell stronger."

source: Singapore Science Center
http://www.science.edu.sg/ssc/detailed.jsp?artid=2996&type=6&root=3&parent=3&cat=30


"When food is heated, it releases more chemicals into the air and your
saliva than when it's cold, so smell sensors and taste buds have more
signals available to send to the brain."
source: Family Fun - Exploring Science
http://familyfun.go.com/parenting/learn/activities/feature/famf010101_famfsense1/famf010101_famfsense6.html

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search strategy:
food smell
"food is heated" smell

Thanks!

Wow that was fast. Thanks