What Einstein Told His Cook 2: The Sequel: Further Adventures in Kitchen Science

448 Pages·2005·3.58 MB·English

by  Robert L. Wolke

CONTENTS
Introduction xv
Acknowledgments xxi
Chapter One • SOMETHING TO DRINK? 3
Why does iced tea turn cloudy? • How does green tea differ from
other teas? • Are enzymes alive? Can I make coffee and tea from
the same kettle water? • Will coffee stay hotter if I put the cream in
right away, or only when I'm ready to drink it? • What are alcohols?
• What is a hop? • Why are there sulfites in wine? • What's so spe-
cial about Sherry? • Does hanging a spoon handle in the neck of the
bottle keep Champagne from going flat? • Why do Champagne
corks have that funny shape? • What makes bourbon bourbon?
• Why does a mint julep glass turn frosty? • What's the best way to
cool a drink with ice without watering it down? • Is there a formula
for telling when I'm getting dangerously drunk? • How can I get a
red wine stain out of a tablecloth? . . . and more.
Chapter Two • DOWN ON THE FARM 51
What ever happened to skim milk? • Why are there so many types
of dairy cream? • Does yogurt contain live bacteria? • Why is soft-
serve ice cream soft? • Does eating ice cream in hot weather really
x CONTENTS
cool one off? • Why does ice cream shrink when it melts? • Why
does all cream cheese come from Philadelphia? • What makes
American cheese American? • Does all cheese need to be pasteur-
ized? • Why is string cheese so stringy? • How does a "nut" of but-
ter thicken a pan sauce? • How are eggs graded? • Are brown eggs
better than white eggs? • Does a blood spot in an egg mean it's fer-
tilized? • Would double-yolk eggs hatch twins? • How can I keep
boiled eggs from cracking? • Why does a hard-cooked egg spin, but
a raw egg won't? • Why do hard-cooked egg yolks turn green?
• What makes an egg rotten? • Why do eggs have dimples? • Can
pasteurized eggs be used the same as unpasteurized eggs? • Are
thousand-year-old eggs for real? . . . and more.
Chapter Three •
WHATSOEVER A MAN SOWETH . . . 107
What makes the vivid colors in vegetables? • Why do green vegeta-
bles turn drab when cooked? • How should fruits and vegetables be
washed? • Why do some potatoes have gray patches? • Is rhubarb
poisonous? • How do vegetables get their minerals? • Why do
onions really make me cry? • Why are "sweet" onions sweet? • Why
is my cucumber bitter? • Why does heated soy milk boil over?
• How do they make tofu? • What is miso made of? • Why do beans
and other legumes produce gas? • Must beans be soaked before
cooking? . . . and more.
Chapter Four • ABOVE THE FRUITED PLAIN 147
How can I speed up the ripening of fruits? • Why does a cut apple
turn brown? • When a banana ripens and gets sweeter, does it con-
tain more calories? • Why are some oils edible and others not?
Exactly what are trans fats? • Why do fats turn rancid? • What is a
CONTENTS Xi
f
free radical? • Does light olive oil contain fewer calories? • What's
"extra" about extra-virgin olive oil? • What is a fatty acid? • What's
the difference between black and green olives? • How does osmo-
sis work? • Why did my strawberry preserves turn out soupy? • Do
all fruits float? • What's the difference between apple juice and
apple cider? • Are "raw" cashews raw? ... and more.
Chapter Five •
FOR AMBER WAVES OF GRAIN 202
What are the different forms of carbohydrates? • What makes
mashed potatoes gluey? • Why do leftover starchy foods turn hard
in the refrigerator? • Is there an easy way to use chopsticks?
• What is converted rice? • Why does unbleached flour cost more
than bleached flour? • How does self-rising flour raise itself?
• What kind of wheat is buckwheat? • How can I best match a pasta
shape with a sauce? • Is the nutritional fiber destroyed when I liq-
uefy fruit in a blender? • Which kinds of fiber contain calories and
which don't? • What is "steel cut" corn meal? • Why do tortillas
contain lime? • What are sugar alcohols? • What is stevia? • Why
mustn't babies be fed honey? . . . and more.
Chapter Six • FROM SEA TO SHINING SEA 238
Why are wild and farm-raised salmon different colors? • Why do
they treat tuna with carbon monoxide? • Do they really make fake
scallops by punching out skate wings? • How does lime juice "cook"
ceviche? • What do I do with bottarga? • What kinds of mussels are
there? • Are razor clams good to eat? • How do wet, dry, and diver
scallops differ? • Why are shrimp different colors? • Why is shrimp
scampi called that? . . . and more.
xii ] CONTENTS
Chapter Seven •
A CARNIVAL FOR CARNIVORES 269
Is "mechanically separated meat" dangerous? • Why is my super-
market's hamburger meat red on the outside and brown on the
inside? • Does marinating work? • -What is souse? • Why are there
rainbows on my roast beef? • Why are hot dogs pink? • Are nitrites
dangerous? Exactly what is braising? • What's the difference
between browning and caramelizing? • Why does food turn brown
when sautéed? • Why are there so many precautions about making
a stock? • Where does simmering end and boiling begin? • Does
adding lemon juice to a stock increase its calcium content? • Why
do we cook with wine? • Which is better for grilling, charcoal or
gas? . . . and more.
Chapter Eight •
SPICE IS THE VARIETY OF LIFE 325
What's essential about an essential oil? • What makes spices spicy?
• Why is cooked garlic so different from raw garlic? • Is garlic pow-
der an invention of the Devil? • Can garlic-infused oil be danger-
ous? • Should herbs be added near the beginning of cooking or
near the end? • How much dried herb shall I use instead of the
fresh herb? • What is the average shelf life of an herb or spice?
• How do pantry-pest bugs survive in a can of Cayenne pepper?
• How do they make liquid smoke? • Is wasabi real? • How can I
keep grated horseradish "hot" in the refrigerator? • Why did
grinding cloves destroy my spice grinder? • How does a salt pig
work? • Why is vanilla so expensive? . . . and more.
Chapter Nine • GALLEY GEAR 367
Does a box of baking soda in the refrigerator kill odors? • Where
should I keep my butter? • Why do foods spoil? Do airport X-rays
CONTENTS [ xiii
sterilize foods? • What's killing my aluminum cookware? • Exactly
what is an emulsion? • Is heat the ultimate form of energy? • -Why
do broilers give such inconsistent results? • In a microwave oven,
why don't two potatoes take twice as long to cook as one potato?
• What's so special about a brick oven for baking breads and pizzas?
• Why do glass and metal baking pans require different baking
times? • How do ovens cook food? • What is silicone? • How does the
shape of a roast affect roasting time? • Does slow, low-temperature
cooking use more or less energy than fast, high-temperature cook-
ing? . . . and more.
Chapter Ten •
A FEW LAGNIAPPES FOR THE
I NSATIABLE INQUIRING MIND 417
What's the difference between heat and temperature? • What's the
difference between melting and dissolving? • What is a "natural
flavor"? • Why can't I pour all the milk out of a carton in one try?
• What are marshmallows made of? • What does the "percent"
number mean on a bar of chocolate? • How does tempering choco-
late change its properties? • -What is that white, moldy-looking
coating on my chocolates? • Is carob a form of chocolate? . . . and
more.
Index 445
INTRODUCTION
T
HIS I s THE SECOND food-focused book, and the fourth book
overall, in what has turned out to be my "Einstein series," a series I
didn't anticipate when I started it. But then, I have never planned the
courses of my careers. I simply followed the advice of Yogi Berra—
whenever I came to a fork in the road, I took it. A succession of forks
has led me from teaching and research in nuclear chemistry to text-
book authorship, university administration, journalism, and trade
book authorship, where you now find me. It was some years ago that I
left my academic career to spend my full time writing, a love of mine
equal to my loves of science and teaching. The "Einstein" books are
one result.
But why would a chemistry professor write about food? For one
thing, good food has intrigued me ever since I first encountered it—
not at my mother's knee, but some twenty years later in graduate
school. Cornell University's College of Home Economics (now the
Division of Nutritional Sciences) operated a cafeteria in which the
products of the students' cooking classes were sold at prices that a
graduate assistant could afford. The menus included foods that I had
never before seen, prepared with the care and dedication that only a
prospective grade of A could inspire. It was perhaps predictable that I
should one day marry my loves of science, teaching, writing, and
XVi ] INTRODUCTION
food, and nestle them between the covers of books. The crowning
stroke of fortune was my marriage to a fifth love (in order of chronol-
ogy, not priority): Marlene Parrish, a restaurant reviewer and culi-
nary journalist full of passion for . . . well, everything that I have
passion for.
when Albert Einstein first walked into his kitchen at
I N 19 35, 112
Mercer Street in Princeton, New Jersey, he of course saw a stove. But
in his mind he also saw an apparatus for transforming the chemical
energy in wood or gas into thermal energy and for conveying that
thermal energy into a chicken. None of which, of course, diminished
his subsequent enjoyment of the chicken, but all of which probably
added an extra bit of spice to his dinner, a spice undetected by less
scientifically tuned intellects.
Science is a sort of intellectual spice that adds depth and allure to
everyday things, not the least of which is food. Food, of course, gives
us pleasure and nourishment. But understanding our food—where it
came from, what it is made of, what happens when we cook it, all in
the contexts of the many experiences and circumstances that make
up the world of gastronomy—nourishes our minds and adds
immensely to our enjoyment of cooking and eating.
The cliché has it that cooking is chemistry. True, but other sci-
ences bear equally on what goes on in our kitchens. There is the
physics of heat transmission, the mechanics of whipping and emul-
sifying, the microbiology of fermentation, the anatomy of meats, the
engineering of utensils and equipment, and the technology of pro-
ducing and packaging prepared foods—all preceded by the agronomy
and animal husbandry that take place on our farms. Kitchen science
is not the mere chemistry of cooking. It involves a lot of what I call
thinking outside the pot.
This book, then, is a truth-seeking exploration of the farm, the
market, and the kitchen by a scientist—not, most assuredly, an Ein-
INTRODUCTION [ XVii
stein, but a scientist with a congenital curiosity about everything he
sees and an urge to share the joy of knowing with others.
THE ENTHUSIASTIC RECEPTION accorded the first volume of
What Einstein Told His Cook, together with the limitless number of
opportunities for scientific scrutiny in the world of food, has inspired
the present sequel. Unlike its predecessor, which focused mainly
on specific foods such as sugar, salt, and fats, the present volume is
organized into eight major food categories: beverages, dairy and eggs,
vegetables, fruits, grains and carbohydrates, seafoods, meats, and
herbs and spices. There is also a chapter on kitchen tools and equip-
ment and a concluding chapter offering a handful of lagniappes to
please not the diner's palate but the reader's inquiring mind.
As she did for the previous book, my wife, Marlene, has wrought
and thoroughly tested (on me) about three dozen tempting and
accessible recipes that put the scientific principles to work in the
home "laboratory."
And as in the earlier volume, the questions come mainly from
readers of my Washington Post column, "Food 101," and thus repre-
sent the concerns of real cooks and consumers, who are often bewil-
dered by the products and labels vying for their attention in today's
multifarious food markets. It is a rare privilege for an author to be in
direct correspondence with a cross section of his readers, so that he
can tailor his writing to their specific needs and concerns.
One of the most difficult decisions to be made in writing a popu-
lar science book is at what level to pitch the scientific explanations.
Too high a level will of course lose the less scientifically sophisticated
readers. But I see no corresponding danger in writing for those who
have studied no science beyond the bare minimum required in most
school curricula, and who will readily admit that even that much
"didn't stick." I therefore write for the latter type of reader without
apology, having been told by scientists, engineers, and chefs that
xviii INTRODUCTION
even they have learned from my previous books. For that segment of
my audience, I dig into my bag of teaching tricks to employ novel
explanatory approaches that can generate fresh insights.
Teaching in a book (and that's what I'm doing) is different from
teaching in a classroom. Each Q&A unit in this book, which can be
read independently, launches a new issue requiring a new explana-
tion. But science is a continuum; it doesn't come in discrete pieces,
like M&M's. Hence, when explaining one concept I have often found
it necessary to restate, very briefly, a closely related one that had
been covered earlier. Otherwise, the unit would be incomplete and
unsatisfying. So please note that I do this intentionally. It's one of my
teaching tricks.
I have explained all concepts in nontechnical language, using
similes and metaphors related to everyday life whenever possible.
Nevertheless, I do present the pertinent scientific terminology in
italics within parentheses, so that the reader can relate it to his or
her other readings and, if desired, follow up on it in more technical
references.
I believe that words, which of course are only symbols for con-
cepts, are often more easily understood if their origins are known.
For that reason I have included the etymologies (and occasionally the
pronunciations) of some of the scientific terms that might otherwise
intimidate the uninitiated.
The current volume is somewhat deeper and richer in science
than the previous one, in recognition of the growing appetite for sci-
ence among foodies, both avocational and professional. I have set
aside the more technical details, however, in sections that I call
"Sidebar Science," which each reader may choose to read or skip,
depending on the depth of his or her scientific interests. Skipping
them will not interrupt the continuity of the text, especially since the
Q&A units are designed to be read independently, wherever one may
chance to open the book.
If, as Miguel de Cervantes wrote in Don Quijote de la Mancha,
hunger is the best sauce in the world, then humor is the best digestif.