Spiced quince crepes

IN the library of almost every serious cook, there is a large amount of real estate, both physical and psychical, given over to one big blue book. Its official title is “On Food and Cooking,” but it’s been years since I’ve heard anyone refer to it that way. Everyone just calls it “McGee.”

I can’t think of very many other food books to achieve single-name status (though there are plenty of food personalities to do so). There’s Escoffier, and Larousse, and that’s about it.

It is Harold McGee’s paradoxical honor to have written in 1984 the single best book in its field and then, pretty much, to have rested. (His only other book is a 14-year-old collection of culinary curiosities called “The Curious Cook.”) That is, until now.

For at least 10 years, people in the food world have been buzzing about the second coming of “On Food and Cooking.” Now that it’s here, at a binding-busting 884 pages, we can finally appreciate what took so long. Remarkably, the revised “On Food and Cooking” (sure To Whom It May Concern: be called “McGee Two”) is as fresh and vital as the original. The science goes much deeper than before, and throughout, it’s more clearly explained.

This is particularly true in the chapters on fruits and vegetables. Take the tomato, for instance. In the first book, it was treated primarily as a historical curiosity. In McGee Two, the history is there, but so is information on tomato anatomy and flavor (the wall contains most of the sugar and amino acids, while most of the acidity is in the jelly and juice), and why tomatoes’ taste and texture change during cooking (and why adding a couple of green tomato leaves can restore that “fresh” taste), and how tomatoes should best be stored (not in the refrigerator). Not every chapter has been so thoroughly revised, but even in those that haven’t, there is enough new that they are significant improvements over the first.

McGee Two cannot be the revolutionary leap forward the first volume was. Until McGee One, the intersection between cooking and science was so remote it wasn’t even on the map. It was as if the left and right brain of the kitchen had not yet been introduced, as if scientists didn’t cook and eat, and cooks thought nothing about the physical processes that were going on in the pan.

There were scientists who studied food, of course, but they reported only to other scientists in food technology journals. To find their results, you had to dig through footnoted papers on meat emulsions in the hot dog industry just to come up with the two or three tidbits that were of use -- or even just of interest -- to the home cook.

By creating a bridge between two worlds, McGee introduced everyday cooks to the inner workings of the science of food, and influenced a whole new generation of chefs and cookbook writers. It’s easy to forget McGee’s contribution in an era when it seems like every Tom, Dick and Harry is writing about food science, but McGee pretty much pioneered the field. Doubtless, eventually someone else would have come along if he hadn’t, but equally doubtless, they wouldn’t have done it as well.

McGee not only was willing to do the scut work of digging through all that desiccated material; he was also able to translate it into elegant, entertaining prose. “On Food and Cooking,” which has sold about 150,000 copies, always reminded me of a book by one of those 19th century gentlemen scholars, graced by a wide-ranging and happily undisciplined curiosity. It’s the kind of book you open just to look up one detail and find yourself browsing an hour later.

Today, of course, it seems that every tyro cook can discuss the Maillard reaction and how braising makes meat tender. Chefs make a minor fetish out of science (and some of them, such as the Fat Duck’s Heston Blumenthal and El Bulli’s Ferran Adria, base their cuisines on it). Conferences are now given over to what is beginning to be called “molecular gastronomy.” And food writers throw around scientific terminology with the same ostentatious aplomb with which their elders used French (and usually to much the same annoying effect).

Meeting the benchmark

So the second coming of “On Food and Cooking” raised two main concerns: First, would there be enough new to say to make the book worthwhile? And, perhaps more importantly, could McGee still make it charming?

You don’t have to read far to find the answers to both questions. The first chapter, while still on milk and milk-based foods, now begins with “The Rise of the Ruminants” (basically how cows -- and cow-like creatures -- conquered the earth when their multiple stomachs allowed them to thrive in areas where nothing else could).

And if this isn’t already charming enough, there are the occasional pithy bulletins from poetry-land. McGee, who has a doctorate in English literature, has a knack for turning up the perfect quote, in one case providing a taste of Seamus Heaney, who describes butter as “coagulated sunlight.”

This intensely personal method of investigation and exposition does have its quirks. As someone whose warmest feelings toward nutrition are probably best described as “deeply skeptical,” I find McGee’s forays into the field intrusive (even though, it must be said, they are sporadic and highly selective). He seems to be particularly sold on the powers of antioxidants; who knows whether this faith will be borne out. Perhaps rather than salting nutritional tidbits throughout the text, he could have wrapped them all into a single chapter that would try to make comprehensive sense of them (and which the agnostics among us could more easily skip over).

McGee is also fascinated by the chemistry of flavor. This is, indeed, a promising area for investigation, but I think it is one that needs to be gone into cautiously. The tastes of most of our foods are the results of extremely complex combinations of dozens, if not hundreds, of compounds (a flavor chemist once told me that even on the most advanced level “we’re dealing with caricatures of flavor, not portraits”).

To single out only a few, as McGee sometimes does, is to risk being misleading. In some cases, a single compound does provide a telling trait. But informing us that peach flavor is distinguished by the presence of lactones is somewhat like describing a human as having brown hair. Lactones are a wide-ranging family found in so many fruits and vegetables -- everything from mushrooms to coconuts -- that no real meaning should be attached.

Finally, McGee’s attitude toward seafood is positively Midwestern in its squeamishness. Even while embracing its wonders, he seems to regard it as a potential cesspool of bacteria and parasites -- kind of like a kindergarten classroom. There is much good information in this chapter, but the suggestible reader would be well advised to keep repeating to himself, “Have I ever known someone who actually contracted liver flukes?”

But these are all minor quibbles. The inevitable bottom-line question in any book like this is how useful it might be. After all, people were cooking quite well long before anyone started thinking about connecting food and science. Given a decent recipe, does any cook really need to know why baking powder foams or why scallops’ “feet” are so tough?

But that seems to me to be missing the point. Although virtually no one will attempt to cook from this book (there are no recipes, though there are some sketchy dish descriptions), it is equally hard to imagine a curious reader not coming away from it a better cook.

Cooking is, after all, a form of applied science as well as an art. Even tasks as prosaic as successfully whipping cream, bringing out the rosy, aromatic side of the woody quince, or making a crepe batter that isn’t tough and chewy rely on an intricate series of chemical and physical reactions. McGee illuminates the everyday alchemy of the kitchen so you understand the very nature of the transformations going on under your hands or in your mixing bowl.

Of course, making it delicious is still up to you.