Why Does Asparagus Make Your Wee Smell?: And 57 other curious food and drink questions

"To start, Andy Brunning points out that not everyone’s does—only people who can break down asparagusic acid, a chemical that is found only in asparagus, will notice the effect. The products of that breakdown are simple sulfur molecules, including methyl mercaptan, the same compound that is added to natural gas to give it a smell to alert people to leaks. Sulfur compounds are notoriously smelly. Even in incredibly tiny amounts, humans can detect their odors at the parts per billion level, so it doesn’t take much asparagus to be able to detect these compounds in your urine. The focus Brunning has on molecular structure through this book is very much in tune with my own research on molecular shape and behavior. Brunning takes us on a molecular tour of what we eat and drink, breaking down the structures of molecules and their reactions to explain why bacon tastes so good and brussel sprouts so awful, at least to those whose are genetically predisposed to tasting the bitter thiocyanates in the latter. He uses bold graphics to show what the molecules look like, giving us a taste of how chemists see the world. Tucked into each vignette is an easily digestible chemistry lesson, from what techniques are used to identify those smelly molecules in urine (gas chromatography) to the quantum mechanics behind why a gin and tonic will glow under a black light (the quinine in the tonic). Support Five Books Five Books interviews are expensive to produce. If you're enjoying this interview, please support us by donating a small amount . This book reminds us that humans are small chemical factories, taking in raw materials, turning them into energy and building materials and producing wastes, some of them smellier or more colorful than others.(What beets can do to your wee is startling). But Brunning also reminds us that we use molecules for pleasure—from the way the menthol in mint binds to the receptors for “cool” in the mouth, tricking us into thinking we’re eating something cold, to the sharp bitterness of the phenylindanes that give a mid-afternoon espresso its extra kick. If you want more of this straightforward explanation of the chemistry we encounter in everyday life, Brunning has a fabulous and growing collection of these graphic explainers on his website, Compound Interest . It’s one of my favorite spots to send friends and family who ask about chemistry in the news."