Introduction

…they’ll sit there on the typewriter and make up all this stuff as if it’s science and then become an expert on foods, organic foods and so on. There’s all kinds of myths and pseudoscience all over the place.

I may be quite wrong, maybe they do know all these things, but I don’t think I’m wrong. I have the advantage of having found out how hard it is to get to really know something, how careful you have to be about checking the experiments, how easy it is to make mistakes and fool yourself. I know what it means to know something, and therefore I see how they get their information and I can’t believe that they know it, they haven’t done the work necessary, haven’t done the checks necessary, haven’t done the care necessary. I have a great suspicion that they don’t know, that this stuff is wrong and they’re intimidating people.

–Richard Feynman, The Pleasure of Finding Things Out

This is a book ostensibly about nutrition and cooking, but it’s really a book about finding things out. We will find out, among other things:

• What are Milankovitch cycles and what do they have to do with the Paleo Diet?
• Can “eat less, exercise more” create a calorie deficit?
• Why is ice slippery?
• Is every soft-boiled egg a food-poisoning risk—or must safe food be cooked dry?
• What is temperature? And what does it have to do with the Planck constant, a fundamental quantity in quantum mechanics?
• What is the molecular and physiological basis for cooking kombu and bonito flakes together in dashi?
• Why does a low-cost particle-size analyzer measure a different distribution of coffee grounds than an industrial analyzer?

You could say this is a book for entertainment, for people who find this sort of thing entertaining. It’s not false modesty. Nobody should take the nutritional advice in this book blindly, and it is certainly not medical advice. Do your own research, have doubts, and validate all claims. That’s what I would do.

It’s also not necessary to read this book to become a better home cook. Good cooking has three components: art, craft, and science. This book only scratches the surface of the science of food. However, it does make cooking more fun, as a natural consequence of knowing what you are doing and feeling in control.

I studied engineering at Caltech and Tsinghua University and spent much of my career in the world of big tech. When I set out to find the secrets of living long and living well (which, for me, means eating well for the most part), I approached it the only way I know how: with a lot of skepticism and a little bit of cynicism. I studied the scientific literature, inspected the evidence, stated the assumptions, and remain suspicious of elegant answers that have not survived a serious attempt to disprove them.

One of my chief grievances with popular science writing is that it often treats its readers as if they are afraid of math. But sometimes a single math equation is worth a thousand words. For instance, I could say that increasing the broiler’s temperature will significantly speed up the toasting process. But how significant is “significant,” and why? The answer lies in the Stefan-Boltzmann law:

where $E$ is radiant power per unit area, $\epsilon$ is emissivity, $\sigma$ is the Stefan–Boltzmann constant, and $T_s$ is the absolute temperature of the surface. The radiant power from the heating element rises in proportion to the fourth power of its temperature. Now that’s significant.

Some have criticized my penchant for including mathematical details. But the math is never there frivolously. An equation stays only when it is load-bearing: it must explain a mechanism, make a prediction, reveal the size of an effect, or help a reader choose between actions. It must be correct, translated into ordinary language, and connected to the food in front of us. I also believe that avoiding straightforward equations out of fear they might confuse readers is, in itself, a form of disrespect. When clearly explained, equations are often the most concise and effective way to communicate complex ideas. To exclude them is to underestimate the reader’s intelligence and willingness to engage with logic and precision.

You can always skip the equations. The conclusion and practical consequence will be stated in prose. But I will not remove a clear piece of reasoning solely because it contains symbols. Doing so would deny the most compact explanation to readers who want it, while assuming everyone else can’t decide for themselves what to use.

The book begins with a discussion of diet plans. It goes into not just the what, but the why. Several myths are debunked along the way. It culminates in a low-stress plan for building a varied pattern of real food.

Cooking your own food is the most reliable and economical way to ensure what you eat is both nutritious and enjoyable. The second half of this book is devoted to the science of cooking. You will not find a collection of recipes here. Page after page of lists, I believe, make for dull reading and do little to inspire culinary curiosity. Instead, the book examines scientific principles, such as the mechanics of heat transfer and the peculiar behavior of water molecules. It follows the science of cooking through heat, water, taste testing, food safety, eggs, toast, steak, coffee, salt, and ice cream. By providing a solid foundation for understanding the properties of ingredients and how the process of cooking changes them, I hope to demystify the process and inspire you to take charge of your own meals.

When you understand the science—or at least possess the confidence to question what you do not yet know—cooking evolves from a mundane task into a creative and intellectually gratifying pursuit. The larger ambition is more modest than certainty and more useful than a slogan: to leave you a little harder to mislead, a little better equipped to ask the next question, and more delighted by the ordinary physical world in your kitchen. If readers experience the joy of figuring out good cooking, the book has done its job.