The Science of Cooking
Dinner Fix-it Quiz

Scene 1:
You've measured the ingredients for your vegetable soup, and put them in a pre-made broth to cook. After adding all the herbs and spices, and salt and pepper, you taste the soup and realize that the broth was already quite salty. Now your soup is salty enough to make you run for running water. How can you take the salty edge off?

A. Add a chunk of potato
B. Add a small amount of sugar
C. Add a bit of fat, like butter, oil, or animal fat

A: You may have heard this kitchen fix offered before. The theory behind it is that a cut-up potato will absorb some of the salt from the broth, and that if the potato is cooked in the broth and removed, voila, you've gotten rid of some of the salt. While it seems that this is gospel for many cooks out there, there's no scientific evidence to support it. Then again, there are no real studies disproving it either. The only thing for certain is that you'll have a salty, cooked potato when you're done.

Try again.

B: It's worth a try. Sugar, used in the right proportion, can help cut the edge off other flavors. You might think it's obvious to add sugar to lemon juice to make a less-sour lemonade. By the same token, sugar added to coffee makes it less bitter. And yes, a little sugar (not too much!) stirred into your soup will make it seem less salty.

This approach can be tricky, though. You're not actually covering flavors, you're adding more flavors to distract your tongue from the one you want to be less prominent. Getting the right flavor balance depends on the ingredients and their proportions in your soup. If the proportion of salt to sugar is too small, they'll actually enhance each other. So you want to add enough sugar to cut the salt, but not so much that it makes the soup sweet. You might want to practice this one before putting it to use.

The reverse of this is also true: Bitter, sour, and salty tastes can lower the intensity of sugar. Keep this relationship in mind when checking the labels on processed foods: Sugar and salt are often used to cover less pleasant flavors that arise when food is processed. Processed foods often contain much more sugar and salt than your palate can detect, and often more than is necessary to balance flavors.

There's another approach that might also be effective. Try the other answers to see what it is, or move on to the next question.

C. Ah, the richness! While fats themselves don’t have a taste, anyone who savors a good cheesecake knows how important fat is to making food enjoyable. Fat won't actually reduce the amount of salt in your soup, but it will coat the tongues of your guests and block some salt from reaching their taste buds.

There's another approach that might also be effective. Try the other answers to see what it is, or move on to the next question.

Scene 2:
Endive is a rather bitter green, and this batch you bought is particularly memorable in that regard. You'd like to tone it down so you don't frighten off your dinner guests, who have never eaten it before. How can you prepare it to make it taste best?

A. Warm it a bit, and serve it with a warm dressing
B. Serve it cold, but add a bit of salt to the dressing
C. Toss it with some juicy tomatoes and some vinegar

A. You're onto something here. Warm temperatures hide bitter tastes. That’s one reason why cold coffee tastes so unbearable. Above about 86° F (30° C), your perception of taste decreases. In order for something to feel warm in your mouth, it has to be above body temperature, which is 98° F (32° C). So if you serve the salad warm, you'll hide some of the bitterness.

Many of the compounds that make your endive bitter are also easily altered or destroyed with a little heat. In fact, some chefs actually grill endive with a little sugar, You don't want to cook it too much, or you'll cook the distinctive flavor right out of it. But a bit of warming might go a long way to making it more palatable.

As an added bonus, the warmth will help bring out sweet flavors in the leaves to counteract the bitterness.

There's another approach that would also be effective. Try the other answers to see what it is, or move on to the next question.

B. Salt is one of your best friends in the kitchen. Among its many useful traits is its ability to hide bitter tastes. You don't want to overdo it here: A too-salty dressing won't be much more palatable than a too-bitter endive. Test your dressing with the greens before you serve it. You'll find the right saltiness will hide some of the endive's sharpness.

There's another approach that would also be effective. Try the other answers to see what it is, or move on to the next question .

C. Nice try, but you're off track. Vinegar is, of course, an acid, and acids provoke sour tastes. Tomatoes are also fairly acidic, which is why an unripe tomato can taste unpleasantly sour. Mixing the two together in a salad will add a lot of acid. That would be great if sour flavors counteracted bitter ones. But they don't. So you'll only be fixing yourself a tangy, bitter salad with this solution.

Try again.

Scene 3:
Your brother has a long plane flight tomorrow, and you know he'd rather eat your home cooking than what passes for food on an airplane. To make sure his in-flight meal is as good as it was in person, how salty should it be?

A. Saltier than usual; our perception of flavors changes at high altitudes
B. The same as usual; the altitude and environment of an airplane don't affect the taste of the food
C. Less salt; the dry air in planes dehydrates passengers

A. Sounds like a good theory, doesn't it? But it's not true. Well, it's not completely true. The conditions in the cabin do have some consequences that affect your sense of taste. But adding salt isn't a good idea.

Have a look at the other answers to learn why.

B. It's not just your imagination that the food you eat on airplanes doesn't taste as good as the food you eat in your kitchen. Altitude and the cabin environment do have an effect on how your food tastes.

Try another answer to learn why.

C. Bland! The less salt, the better. Airplane food is bland, and now you know one reason why: because the food often contains less salt than you're used to. Airplane cabins have very low humidity, and it's easy to get dehydrated when flying. The chefs who put the menus together don't want to exacerbate the problem with extra salt, so they cut back. The food tastes less flavorful, particularly to American palates that are used to rather salty dishes.

Next question.

Scene 3a (the flight continues):
Some flavors will work better than others in the environment of an airplane. What's the best approach to flavoring your dinner if you're going to take it on the flight?

A. Use subtle herbs and spices; our sense of smell becomes more sensitive in the increased pressure of the cabin
B. Use flavors that affect our sense of taste more than our sense of smell (for example, salty rather than garlicky)
C. Use more acidic (sour) flavors; our perception of pH is affected by the plane's altitude and cabin pressure

A. Nope. While cabin pressure may have an effect on how well we can hear things, it doesn't cast any shadows on our sense of smell. There's no need to be more subtle with flavors than you ordinarily would. In fact, it would be a good idea to up the herb and spice ante to make up for the fact that you'll be using less salt (remember the answer to the last question?).

Try again.

B. Exactly. But to understand why, you need to know a few things. First, most of what you probably think of as taste is actually smell. That's not to say your nose is more sensitive than your tongue, it only means you make more use of your nose when you eat than you might realize.

Second, you taste things because they land on your tongue. How you smell things is a little less straightforward. Odor molecules float from your food through your nasal passages to a mucous membrane surrounding your olfactory system. From there, those molecules make a connection to your olfactory nerves. Without enough mucous, the system doesn't work as well. Because the plane's arid cabin is likely to dry up a bit of your sense of smell, sweet-and-sour chicken is a good choice: Sweet and sour are both flavors you experience with your tongue, and so are less affected by the cabin pressure than, say, an aromatic curry would be.

C. Nope. As bad as airplane food might be, it's not due to your distance above ground. Sour is sour is sour at any altitude.

Try again.

Scene 4:
After mixing the sauce for your sweet-and-sour chicken, you taste it. It's awfully sweet. What's the best way to take that down a notch?

A. Add a pinch of salt or more soy sauce
B. Add more sour flavor, like lemon or vinegar
C. Add some aromatic flavoring, like garlic

A. Under ordinary circumstances, this would be as fine a choice as any. A little salt will counteract sweet tastes, just as sweet counteracts salty (remember the vegetable soup in scene 1?).

This is a different circumstance, though, because your brother is going to be on a plane, and you don't want to put any more salt into the dish than you need to. Try again.

B. Well, it is sweet and sour, isn't it? If it's too sweet, then adding more sour is an obvious choice. This is true for anything that's too sweet, even if the objective isn't to create a sweet-and-sour dish. In fact, one taste unfettered by the others—pure sugar or sweetness, for example—is often uninteresting. That's why even candies like lollipops sometimes have a dash of citric acid to brighten the flavor. See the lollipop recipe in the Science of Candy section.

C. Garlic may be able to save a dish from a lack of flavor, but not from a lack of sweetness. Because you experience the flavor of garlic mostly through your nose, and you taste sweetness with your tongue, adding one to the other simply adds to the overall flavor of the dish.

Try again.

Learn more about taste and smell .

Scene 5:
The clock has been ticking while you've been cooking. By the time you look up from your sweet-and-sour chicken, it's much later than you thought. Yikes! You try the sauce again, and it tastes fine. But when your sister, who's only worrying about eating and not about cooking, tries it, she says it's still too sweet. What gives?

A. Foods taste different to different people, and your sister's taste buds may be more sensitive than yours to sweet tastes
B. Your sister may not be used to sweet foods, so the sweetness in your recipe may affect her more strongly
C. Because you're nervous about your dinner party, your taste buds are more sensitive to sour tastes

A. There's some truth to this. The number of taste buds varies widely from person to person. Some people may have many thousands, while others have only several hundred. Most of us are somewhere in the middle. People who are on the higher end of the spectrum are called "supertasters," because the number of taste buds they have makes them very sensitive to tastes. Supertasters tend to like their food blander, and they find foods with pepper or chili in them hotter than someone with the average number of taste buds.

Despite this, there may be more to the difference in palates between you and your sister. Try again.

B. People's palates do seem to adjust to flavors. It's not clear whether our taste buds actually change their sensitivity, or whether it's more of a psychological familiarity with certain flavors. Either way, there may be other factors at work influencing your tasting experience.

Try again.

C. Does this question leave a sour taste in your mouth? That could be because anxiety can change the way you taste things. Scientists still have a lot to learn about this phenomenon, but what they do know is that hormones like cortisol, which your glands secrete when you're nervous, create changes in your body, some of which affect your mouth. For starters, you produce less saliva, which means less effective breakdown of food molecules in your mouth. Some researchers have found that cortisol dampens the effect of sensory input, particularly taste stimuli. And some scientists believe that stress increases the levels of acidity in your mouth. In extreme cases, this can lead to mouth ulcers, better known as the common canker sore.

Bottom line: Trust your sister on this one, unless you're expecting your dinner guests to be nervous, too!

Scene 6:
Spicy green beans are one of your favorite dishes. But after Aunt Anne warns you that spicy foods can make her disposition sour, you want to be careful not to set her off. What should you keep in mind while preparing the dish?

A. Go ahead and use your red chilies, but remove the seeds, which are the hottest part of the pepper
B. Use your red chilies, but remove the spongy ribs inside, which are the hottest part of the pepper
C. Use green chilies rather than red

A. Though this is the common wisdom, it's not quite accurate. Capsaicin, the alkaloid compound that produces hotness, is usually found in some quantity in the seeds, but that's not where it's most abundant. If you're trying to keep the temperature as low as possible, it's important to remove the seeds. But that's not the whole story.

Try again.

B. Hot diggity! The heat that peppers impart comes from an alkaloid compound called capsaicin, which is manufactured in the ribs of the chili pepper. The way to really keep the heat down is to remove these spongy inner parts. The seeds usually absorb capsaicin from resting near the ribs, so it's best to remove those, too.

Capsaicin itself doesn't have any flavor; it stimulates the pain receptors in your mouth rather than your taste buds. The Scoville scale is used to rate the hotness of chilies: Mild red bell peppers rate a zero, poblanos rate 1,000, all the way up to habaneros, at over 100,000 heat units.

Next question.

C. When it comes to heat, chili peppers are colorblind. Red ones have gotten a reputation for being hotter than green ones, but that's not a reliable measure. Mature chili peppers are hotter than immature ones, but a green habanero pepper packs a whole lot more heat than a red cayenne.

What does differ between chilies is the exact chemical makeup of capsaicin. Some chili peppers, like the zingy habanero, deliver a stinging bite that quickly fades. Others, like the more sluggish jalapeno, offer a less alarming strike, but can hang around your palate much longer.

Color can be an indication of flavor, though. The colored flesh of the chili is where the taste is, and the stronger the color, the more robust the flavor will be.

Try again.

Scene 7:
You made your green beans sans spongy chili ribs, and you took the seeds out for good measure, too. But it's still too hot for Aunt Anne. Before she gets grumpy, what should you advise her to do?

A. Eat bites of the chicken dish in between bites of green beans
B. Drink water
C. Add a bit of yogurt, sour cream, or other dairy product to the dish before she eats it

A. If you want to keep some of the heat, but moderate it to tolerable levels, this is a good solution. Sugars and acids together can help neutralize the sting of capsaicin. This is something to keep in mind when eating at Asian restaurants, as well: If you want to order one rather hot dish, you can choose a sweet-and-sour to go with it, as a way of toning your palate down.

This approach won't cut right through the hot spots in your mouth and offer instant cooling. There's something else you could offer at the table.

What do you think that would be?

B. You won't drown out the pain this way, despite your instinctive reach for the glass. In fact, drinking water has little to no effect. Capsaicin isn't soluble in water, so a good long drink doesn't do much to alter its burning potential.

Try again.

C. Ahhhh, relief! Dairy products are a good antidote to overheating. Capsaicin — the compound that gives peppers their heat — dissolves easily in the fats found in dairy products. So when you put a dab of sour cream in your mouth along with (or after) a bite of hot stuff, you're adding pretty effective dilution. The capsaicin and dairy fats mix together, keeping some of the capsaicin molecules from finding the pain receptors on your tongue.

This antidote tones down many spicy cuisines, from the use of sour cream with Mexican food to the yogurt condiments eaten with Indian meals. In Thai cuisine, rich coconut milk serves much the same purpose, but it's added directly to the dish, adding body and flavor. Remember, though, it's the fat that provides the relief, so don't expect the same results from low-fat sour cream or nonfat yogurts.