I learned a lot from this book, but be warned - pleasurable reading it does not make. So you don't have to, my main insights:
What we call ‘flavor’ is the combined qualia from smell and taste, and smell is far more influential for our perception of flavor than is taste; you probably know this from holding your nose while swallowing cough syrup. Taste, as a sense in itself, is quite limited. It can only detect salts, acids, sugars, bitters, and umami (glutamates). Only when combined with the other senses can the full picture of flavor emerge.
Furthermore, the idea that we have five senses comes from Aristotle and is not up to date (see: proprioception). In fact we have two senses of smell, orthonasal (front of nose) and retronasal (back of mouth), and it’s the latter that makes things taste like they do. When you breathe out, molecules from the food/bolus in your mouth and esophagus enter the nasal channel through the back of your mouth and stimulate your rich retronasal receptors. Dogs and other animals have acute orthonasal but limited retronasal smell, thus humans are unique in our flavor perceptual capability.
A few ideas new to me:
“Smell has the property of being, in general, ‘synthetic’; that is, a mixture of several smells makes a new unified smell. It is not ‘analytic,’ the way taste is: sweet and sour tastes sweet and sour rather than being a new unified taste. [p.32]”
If you’ve ever wondered why you have a “second stomach” for dessert: “In the 1950s he [Jacque Le Magnen] began detailed studies of laboratory rats fed different kinds of diets. He found that on daily lab chow they showed little weight gain, but if he offered them chow with different flavors they quickly began to gain weight. This effect was rediscovered in 1981 by Barbara Rolls and her colleagues at Oxford, who callide it sensory-specific satiety, meaning that with one flavor the animal quickly becomes full and bored with eating more, whereas a new flavor stimulates renewed eating. [p.189]”
“[A] famous study… showed that an animal that has been made sick from a food just once will avoid that food ever after, even though the sickness occurs many hours later. It is called conditioned taste aversion; in field studies of animals it is called bait shyness. Because it requires only one episode of sickness, it is also called one-trial learning. Bait shyness is so much more powerful than classical learning, which involves many paired associations between stimuli, that at first few psychologists believed it… When we suspect a food has made us sick, we lose our taste for it and search through our memories for the cause of it. [p.126-127]”
The diagram on page 161 is also excellent.
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So, why does this only net three stars? As is advertised on the back cover, “Chefs and food lovers alike can benefit from a better appreciation of the phenomena at play throughout the culinary process, from the field to the fork and beyond.” While unlikely to be of interest to the general reader, the book is also not ostensibly targeted towards a scientific-academic audience. It just happens to be (largely) written for one.
Several chapters, especially 5 through 12, can only be deciphered by folks with at least a collegiate-level understanding of biochemistry or neuroscience, or those who parse through related research journals for fun. I cannot justify filling more than 60 pages (25% of the book) with uninterpretable and therefore soporific discourse, and I also don't need complex research histories with profligate name-dropping. Credit where credit’s due, Gordon Shepherd, but this sort of narrative has no place in a book based in positive epistemology; readers can intuit that 2012 is 2012.
Just the facts, please.