Now, how it is we see some food for some,
Others for others . . .
I will unfold, or wheretofore what to some
Is foul and bitter, yet the same to others
Can seem delectable to eat?
his book began with a conversation about grapefruit, and how in the past they were bitter. My friend Laura, also a cookbook author, and I were lamenting the changes wrought to this wonderful fruit by marketing boards and the North American sweet tooth. When was the last time you tasted a proper bitter grapefruit with white flesh? For me, it has been years. The grapefruit of my childhood have been replaced with pink, sweet ones. Yes, today's grapefruit still has some acidity, but it has lost its bitterness and as a result is a fruit much less interesting to eat.
I grew up with bitter grapefruit. My mother conscientiously made me a three-course breakfast every morning before sending me off to school. This probably explains why today I avoid breakfast, drinking only a café au lait in the morning. However, I fondly remember the grapefruit halves she served, prepared with a grapefruit knife. This specialized knife, serrated on both sides, is gently curved, allowing you to separate the grapefruit flesh from its pith and skin. Once done, you cut between the membranes, making the segments easily accessible to a small spoon. The natural bitterness of the grapefruit's flesh was tempered with a light sprinkling of sugar and the ready-to-eat fruit was presented in a bowl.
Later, when I began cooking, grilled grapefruit was a popular starter in hotel restaurants; it was prepared as my mother had done it, but with all the pips removed and a shot or two of sherry added. Topped with a mixture of brown sugar and a little butter, the fruit was slipped under the broiler until the sugar caramelized. The result was the perfect balance of bitter and sweet to stimulate the appetite.
My experience with grapefruit gave me a positive attitude to bitter, and it became an important part of my flavor palate. As I explored the world of bitter food, citrus zests, turnips, rapini (broccoli raab), chicories (endives), and cardoons became some of my favorite tastes, and I found myself craving them. They were for me, as Lucretius said, "delectable to eat," though other people found them "foul" and were unwilling to try them.
A reluctance to eat bitter foods is understandable, as we all have an innate aversion
to bitter tastes. Our tongues are covered in taste buds that are very adept in detecting even the smallest traces of bitterness. This is a natural defense system to protect us:
many poisons are bitter, so our response when tasting something very bitter is to grimace and often to spit it out. This reaction is strongest in babies, as small amounts of toxins can kill them. As we age, we lose taste buds, and we also learn that not all bitter foods will kill us. In fact, we realize that many bitter foods, like coffee, bitter alcohols, and chocolate, stimulate our nervous system in ways we enjoy, so we actively seek them out. Over time we have also discovered that many bitter foods contain compounds that can protect us against illness, and positively influence our health.
So does it matter if we avoid bitter? Absolutely yes! Bitterness is a double-edged sword: it signals toxic and dangerous, but it can also be pleasurable and beneficial. In the kitchen, eschewing bitter is like cooking without salt, or eating without looking. Without bitterness we lose a way to balance sweetness, and by rejecting it we limit our range of flavors. Food without bitterness lacks depth and complexity.
Looking around, I can see that interest in bitter is on the rise. It's returning to the drink world, with a growing interest in cocktails containing bitters; a good Manhattan is impossible without them, and bitter alcohols, like European aperitifs and Italian amaros, are becoming popular. Bitterness is slowly making its way into the North American culinary consciousness, too. The last decade or so has seen a huge increase in the popularity of bitter lettuces, beginning with mesclun mix; now bitter greens like arugula, dandelion, radicchio, and frisée are common in restaurants. Alongside these lettuces, vegetables like brussels sprouts, turnips, and white asparagus, all of which have a bitter edge, are appearing frequently on menus. Chefs are highlighting the bitter components of nuts and fruits like walnuts and citrus, and bitterness is an important part of the flavor profile of quality olive oils. The makers of craft beer exploit the bitterness of hops, while artisanal chocolate makers create bitter chocolate bars with higher and higher cacao content. Surely the time is right, I decided, to champion the use of bitter in the kitchen.
First I would have to define "bitter." I thought that would be easy until I actually tried to do it. When I discussed the taste of bitter with others, I realized that what I think of as bitter is not necessarily bitter for other people. Some even argued that grapefruit, which were the spark for this book, aren't even bitter: they're simply sour. Perhaps these people had never eaten a white grapefruit? Or was it a tougher problem than that? Was it possible to pin down the taste of bitter?
We can probably all agree that Fernet-Branca, rapini, citrus zests, and beer are bitter, but I became more aware of the diversity of what we think of as bitter when numerous friends, all working in the food world, sent me suggestions for foods to include in the book. While I agreed with most of their ideas, some surprised and even shocked me. Among them were Camembert, celery, cucumber, Campari, Belgian Chimay cheese, eggplant, lemons, pickled onions, rhubarb, Seville orange marmalade, sorrel, coffee, and white Châteauneuf-du-Pape wine. Aren't rhubarb and sorrel simply sour? Lemon is both sour—its juice—and bitter—its peel. Celery, cucumber, Seville orange marmalade, Campari, and white Châteauneuf-du-Pape wine all have bitter notes, but eggplant is rarely bitter today. The bitterness of Chimay cheese comes from its beer-washed rind, and I've discovered that cheeses made with cardoons have a touch of bitterness, but Camembert? Not in my experience. Perhaps my friend had a cheese that was a little sour and confused that with bitterness? How our food is prepared also influences our perception of bitterness. Coffee gets only a small amount of its bitterness from the caffeine; most of it depends on how the beans are roasted and the method used for brewing it. Bitterness covers a wide span from aggressive to subtle; realizing that it is much more nuanced and difficult to pin down than the other tastes, I turned to science.
Specifically, I contacted Professor Russell Keast from Deakin University. Professor Keast works a stone's throw away from where I went to school in Melbourne, Australia. Not only is he a professor of food and sensory science, a member of the New Zealand Guild of Food Writers, but he was also a chef—so he's a man who can understand bitter from my perspective. He observed, "[Bitter] conveys a very simple hedonic message—if excessive, don't consume." That message, according to Keast, probably has something to do with why many of my foodie friends confused sour and bitter: this mix-up is common because both tastes can trigger a negative reaction in high doses. He also shone a light on the relative elusiveness and complexity of bitter: while only acids signal "sour," by contrast thousands of different compounds in foods elicit a "bitter" response.
And taste is only one of our senses that indicate bitterness. Smell, temperature, color, texture, and how the food feels in our mouth all relay a sense of bitterness to our brain. The pungency of arugula and horseradish can evoke a taste of bitter, as can the astringency that you find in celery, or the tannins in tea and cooked apricots. These sensations are delivered not through our taste buds, but via our somatosensory system, which includes touch, temperature, and texture. Beyond immediate sensory input are a whole range of cultural, environmental, experiential, and genetic factors that play a role in our perception of bitterness. The food's visual impact is very important, as is anything we have heard or read about it. These factors set up expectations about a food, so that we often dislike something even without tasting it because of how it looks, or how we think it will taste. What I find mildly bitter can be extremely bitter for others, just as the rutabaga that tastes bitter to me tastes sweet to many of my friends.
So when it comes to bitter, our understanding of it—even our experience of it—differs more widely than that of any of the other basic tastes. Bitter is not simply a reaction on our tongue—a taste in the strict sense—but also includes many different signals that register as bitterness in our brain. I was discovering that bitter was even more intriguing and perplexing than I had originally thought. To decipher bitter I would have to unravel the science of how our brain determines flavor. The research in this area is developing rapidly, and it encompasses everything from anatomy and genetics to culture.
The culinary history of why we keep bringing this taste into our kitchens despite our natural dislike of it gives another insight into bitter's persistent allure. As cooks, if we understand the role of bitter in the flavor spectrum, we can exploit and harness it in the kitchen. Cooking is about balancing tastes, and bitter often plays a vital role in a dish's harmony; it is crucial to the composition of a meal or menu. Without a touch of bitterness, your cooking will be lacking a dimension. Furthermore, bitter is both an appetite stimulant and a digestive—that is, it has the power to make you hungry as well as helping you digest your meal.
Here you'll find a mixture of recipes, culinary and physiological science, literary tidbits, and history. Like me, you'll probably be surprised by what you'll read here; it may make you rethink how you cook, serve, and savor a meal.
The complexity of bitter—and the individual variation we bring to experiencing it (see pages 24 and 35)—makes any exploration of the subject subjective. Mine, documented in this book and still unfolding (see page 247), reveals the prejudices of my palate and experience. I haven't included everything we eat that tastes bitter, and some of what I find bitter (pungent, harsh, tannic, astringent) you may not. My goal is to open up the possibilities in how you see bitter, so that while you may not become a lover of Fernet-Branca, you might cultivate a craving for a salad of bitter greens—to the benefit of your health and the delight of your palate.
It's worth trying to imagine bitter through the lens of the Japanese word shibui, which describes a tangy bitterness. According to Kinfolk Magazine, "When people are described as shibui, the image is of a silver-haired man in a tailored suit, with a hint of a bad-boy aura about him." So bitter is a cultured, intriguing, and sophisticated taste, with a dangerous side. Who could be more fun to cook or to dine with?
Bathed in Butter
Often, recipes for endive begin by boiling them, but as British chef and food writer Simon Hopkinson points out, "When cooking endive it is absolutely essential that you do not use water. The endive itself is pretty well all H2O." Cooking Belgian endive in water leaves you with a tasteless, waterlogged vegetable; it's probably why you think you don't like cooked endive. Here I've adapted Hopkinson's recipe, slowly caramelizing them in butter so they become meltingly soft. The butter enriches them and mellows their bitterness. You need a pan just big enough to hold the endives snugly, as they'll shrink as they cook. Serve them with a grilled veal or pork chop. Or try them in Belgian Endive Flemish Style (opposite).
8 Belgian endives, about 1¾ pounds / 800 g
7 tablespoons / 31/2 ounces /
100 g unsalted butter, diced
Sea salt and freshly ground pepper
3 tablespoons freshly squeezed lemon juice
Preheat the oven to 300°F / 150°C.
Wipe the endives with a damp cloth and trim their bases, if necessary. In an ovenproof frying pan with a lid, just large enough to hold the endives in a single layer, melt the butter over low heat. When the butter is melted, increase the heat to medium and cook the butter, shaking the pan from time to time, until the milk solids begin to brown and you can smell
a nutty aroma.
Add the endives and lower the heat. Turn them to coat with the butter and season with salt and pepper. Cook the endives until they are lightly colored, then pour in the lemon juice. Cover the pan and place in the oven for 1 hour. Remove the pan and turn the endives carefully, cover, and return to the oven. Cook for another 45 minutes to 1 hour, until the endives are limp and very, very soft.