Smells are mixtures · SmellBook Learn (free) · smellbook.com/learn/science/smells-are-mixtures
SMELL AND SCIENCE · LESSON 1 OF 6
Is a smell one molecule or many?
Most familiar smells are made of many volatile compounds, molecules light enough to travel through the air to the nose. A review of strawberry aroma counts more than 360 of them in the fresh fruit.
Yet only some of those compounds shape the smell people recognise. Much of the research below asks which ones matter, and a single molecule rarely tells the whole story.
Volatile classes behind strawberry aroma (VERIFIED): A review reports that fresh strawberries contain more than 360 volatile compounds, including esters, furans, terpenes, alcohols, aldehydes, ketones and sulfur compounds, and that terpenoids, furanones and sulfur compounds, though far less concentrated than the esters, have a considerable impact on how their aroma is perceived. Scope: Compound classes rather than individual key odorants; the review also covers how drying changes the profile.
Key odorants of butter (VERIFIED): A review of aroma studies reports that sweet cream butter is characterised by lactones and sulfur compounds, while the key odorants of sour cream butter are diacetyl, butanoic acid and δ-decalactone, formed mainly by lactic acid bacteria. Scope: Key odorants differ between sweet cream, sour cream and heated butter and butter oil.
Coffee aroma is chemically complex (VERIFIED): Coffee aroma is chemically complex: a review of how its volatile compounds are analysed finds them challenging to resolve and concludes that no single analytical method captures that complexity on its own. Scope: Supports aroma complexity and the limits of analysis; it does not give one fixed list of compounds that defines every coffee.
- Smell a strawberry or a slice of bread slowly. Try to name two separate notes in it, such as sweet and green, or toasted and buttery.
Finding the molecules that matter
Smell and Science is free, like all of SmellBook Learn. It covers where smells come from: the volatile compounds behind them and how researchers find the ones that matter. Every finding is a VERIFIED claim shown with its scope. It is not medical or safety advice. Lessons on smell receptors, perception and adaptation will be added when registered sources support them.