The science behind apple sweetness and tartness

 
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Braeburn, Bramley, Clivia, Dabinett, Gala, Jonagold and Reinette. No, not an excerpt from the class list at your local private school, but a selection of the names of the over 7,500 different cultivars of apples. Each of these cultivars has its distinct flavour and character — and a bit of biochemistry can help us understand why.

Apple festivals are a regular autumn occurrence across England, and it was at one last weekend that I got thinking about the chemical variety in different apple cultivars. I confess to not being a huge apple fan unless they’re juiced, baked in a pie, or in the form of cider. Consequently, I’m aware that the delights of all of these varying cultivars are mostly lost on me. However, I was still curious as to what molecular differences underlie the contrast between sweet and tart apples, and whether there are straightforward chemical explanations for the varied flavours of differently named apples.

Celebrating 40 years of chemical drawing with ChemDraw

 
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The year is 1985. Windows 1.0 has just been released in North America, and the first Back to the Future film is playing in cinemas. Chemists worldwide who need to draw chemical structures have no choice but to use a combination of freehand drawing, stencils, and dry-transfer letter decals. However, a former high school science teacher, a Harvard PhD student and a chemistry professor are about to revolutionise how chemists depict molecules.

The chemistry professor is David Evans, a prominent organic chemist who moved to Harvard from Caltech in 1983. Sally Evans, a high school teacher, moves with him and becomes his research group’s administrator, laboratory architect, and graphic designer. The latter involves drawing the countless chemical structures the group are working on, a time-consuming task often requiring the repeated drawing of complex structures for reaction schemes.