Chapter 10: Brewing and Chewing

Density is defined as mass per volume. If 1 cup of butter is equivalent to 226 g of butter, and 1 cup is equivalent to 250 mL, what is the density of butter in g/mL?

0.90 g/mL (mass/volume)

A banana can be eaten off of a tree or cooked in dishes. What is the purpose of cooking the banana?

To transform its taste

In the sous vide method of cooking, food is cooked under ______ and at a temperature _______ the temperature at which it is to be served.

vacuum; the same as

A liquid can evaporate at any temperature, producing vapor above the surface of the liquid. This vapor exerts a pressure, which is called the _____ pressure. This pressure _____ as the temperature of the liquid increases. When this pressure equals the external pressure, the liquid has reached its boiling point.

vapor; increases

A cookie recipe calls for 1212 cup of butter, 1 cup of sugar, 2 eggs, and 11414 cups of flour for 2 dozen cookies. You need to make 150 cookies for a bake sale. How much of each ingredient do you need? Select all that apply.

31818 cup butter 61414 cups sugar

A cookie recipe calls for 1212 cup of butter, 1 cup of sugar, 2 eggs, and 11414 cups of flour for 2 dozen cookies. You have 11212 cups of butter, 21212 cups sugar, 6 eggs, and 4 cups of flour. How many cookies can you bake?

60 cookies

Why do bubbles rush out of a carbonated beverage when the container is opened?

CO2 becomes less soluble in the beverage when the pressure is released.

What chemical changes occur when meat is smoked? Select all that apply.

Collagen in the meat is converted to gelatin, which causes the meat to become more tender. NO2 from the smoke creates a more acidic environment in the meat, changing its color.

Which of the following include reasons to transform our food in some way? Select all that apply.

Cooking food may kill dangerous organisms. Transformation of food may improve the taste.

Which of the following options correctly describe how a microwave cooks food? Select all that apply.

Microwaves allow heat to be generated by friction as the molecules in the food move more rapidly. Microwave radiation causes molecules to rotate and bump into each other more frequently.

Which of the following correctly describe steps in the processing of coffee? Select all that apply.

More flavor is extracted from finely ground coffee beans. Roasting of coffee beans improves the flavor of coffee.

When food is salted for preserving ________. (Select all that apply.)

NO formed from nitrites and nitrates binds to the iron in hemoglobin NaCl added to the food causes water to be removed nitrites and nitrates are antioxidants and kill bacteria

Tuiwa, Tibet is one of the tallest places on Earth and Death Valley, California is one of the lowest places on Earth. Which statement best describes which location would require longer cooking times and why?

Tuiwa, Tibet would require longer cooking times because the boiling point is lower.

Match each region of the tongue to the principal taste receptors found there.

Yellow (at the back) ----> bitter Blue (on the sides) ----> sour Green (center) ----> not many receptors Pink (at the front) ----> salty/sweet

The relationship between pressure and temperature is _____.

a directly proportional relationship

In the process of fermentation ______. (Select all that apply.)

a micro-organism such as yeast is required glucose and other sugars are converted to ethanol CO2 is produced

Drying and curing preserve foods by _______.

adding salt removing water

The alcoholic mixture produced by fermentation of sugars can be distilled, a process that separates liquids based on their ______. This allows ethanol to be separated from water, resulting in a solution with a ______ alcoholic content.

boiling points; higher

A refractometer _______. (Select all that apply.)

can be used to determine specific gravity is often used to determine the sugar content of a solution detects the bending of light in a solution

Lecithin, found in egg yolks _______.

can interact with both polar and nonpolar molecules is an emulsifying agent has both polar and nonpolar portions

A thermometer would be most helpful or necessary when preparing _______. (Select all that apply.)

candy fried chicken roasted meat

Which of the following are qualitative methods of determining food readiness? Select all that apply.

checking the degree of browning when frying an egg the "fist test" for grilled meat the "soft ball" test for candy

During the distillation process, the distillate is cooled in the _______ to form a liquid that can be collected.

condenser

The condenser in the distillation process _______.

cools the distillate, causing it to condense so that it can be collected as a liquid

In cooking, thermometers are most typically used for _______. (Select all that apply.)

determining the internal temperature of meat ensuring the oven is at the correct temperature measuring the temperature of a sugar mixture when making candy

Ethanol has a polar -OH group allowing it to dissolve readily in water and a small hydrocarbon portion, which allows it to interact with nonpolar solvents and cell membranes. We describe ethanol as having _______.

dual polarity

An emulsion such as mayonnaise can be stabilized by adding a(n) _____ agent, such as the lecithin found in egg yolks.

emulsifying

Mayonnaise is an example of a(n) _____, in which a nonpolar substance is dispersed in a polar solvent. This normally incompatible system is stabilized by the _____ in the mayonnaise.

emulsion; egg yolk

The process in which yeast converts sugars to alcohol and CO2 is called ________.

fermentation

When room-temperature pasta is placed in boiling water, heat flows _________, causing the pasta to cook.

from the water to the pasta

A foam is formed when a ______ is trapped in a ______.

gas; liquid or solid

Drying and curing are suitable methods of food preservation because ______.

harmful microbes also rely on water to survive

Compared to UV, IR, and visible radiation, microwave radiation ______. (Select all that apply.)

has a lower energy causes molecules to rotate rather than breaking bonds

Mayonnaise is an example of an emulsion, which ______. (Select all that apply.)

has a nonpolar substance dispersed in a polar substance would settle out unless stabilized

Smoking food to preserve it involves _______.

heating the food for a long period of time in the smoke produced by a fire

When a carbonated beverage is sealed, the pressure on the beverage is _____ than atmospheric pressure. When the can is opened, the pressure on the liquid _______ and the dissolved CO2 bubbles out as its solubility decreases.

higher; decreases

The greater the concentration of sugar in a solution (such as beer or wine), the ______ its specific gravity and the ______ its refractive index.

higher; higher

Food cooks when heated because the spontaneous flow of heat is always from an object at _____ temperature to an object at ______ temperature.

higher; lower

A _______ is an instrument that measures changes in the density of a liquid.

hydrometer

Henry's Law states that the amount of gas dissolved in a given volume of solution will ______ when the pressure increases.

increase

The refractive index of a solution ______ as its specific gravity increases. This relationship is ______.

increases; linear

A foam may be produced by _______. (Select all that apply.)

injecting a gas into a thickened liquid at higher pressure beating air into a solution with a spoon or beater

During a phase change such as liquid → gas for a molecular substance, the temperature of the system _______.

is unchanged

The intermolecular attractions between water molecules are relatively strong, so that water requires a significant input of energy to overcome these attractions and change phase. Water is said to have a high ______ heat.

latent

The alcoholic solution produced by fermentation can be distilled by heating in a still. The compounds with ______ boiling points evaporate first and so the distillate contains a ______ concentration of ethanol than the liquid left behind.

lower; greater

A liquid boils when its vapor pressure equals the external pressure. At higher altitudes the atmospheric pressure is lower and the liquid therefore boils at a ______ temperature. Food may therefore take _______ to cook at higher altitudes.

lower; longer

Microwave radiation has a ______ energy than UV, IR, or visible radiation and will therefore ______ in the molecules in food during cooking.

lower; not break bonds

A hydrometer, which measures changes in liquid density, would most typically be used for _______.

monitoring a fermentation process in beer or wine making

Which of the following substances may be used in the salting or salt-curing of foods? Select all that apply.

nitrite salts NaCl nitrate salts

Oil does not readily mix with water because oil is ______, while water is _______.

nonpolar; polar

_____ receptors bind with the aromatic compounds found in food.

ordor

The statement "like dissolves in like" means that ______.

polar substances will dissolve most readily in polar solvents

During the phase change of a molecular substance the temperature of the system is constant because heat transferred is used to change the ______ energy of the molecules by breaking or forming intermolecular attractions. Since there is no change in ______ energy of the molecules during this process, the temperature does not change.

potential; kinetic

When determining food readiness, methods such as dropping cooked sugar mixture into cold water to determine its cooking stage are ______ methods, whereas the use of a thermometer to measure temperature is a _______ method.

qualitative; quantitative

A refractometer measures the extent to which a solution refracts (changes the direction of) light, which is expressed by its _____. This quantity _____ as the specific gravity of the solution increases.

refractive index; increases

Microwave radiation causes molecules in food to _______, which results in increased movement and increased ______ between the molecules, which in turn generates the heat required for cooking.

rotate; friction

Experts agree that the human tongue detects six basic tastes, which include ______. (Select all that apply.)

salty sour fatty sweet

Which of the other senses plays a major role in recognition of taste?

smell

The flavor components in both tea and coffee are extracted on the basis of their _______.

solubility in water

A pressure cooker allows food to cook faster because ______.

the boiling point of water is higher under higher pressure

Ethanol, like other alcohols, has dual polarity because ______. (Select all that apply.)

the carbon portion of the molecule can interact with nonpolar substances the polar -OH group can interact with H2O and other polar substances

In the sous vide method of cooking _______. (Select all that apply.)

the food to be cooked is vacuum sealed food is cooked at the same temperature at which it is to be eaten

The boiling point of a liquid is the temperature at which ______.

the vapor pressure of the liquid equals the external pressure

Water has a high latent heat. This means that ___________.

water can absorb a lot of heat before changing phase

Henry's Law expresses the relationship between the concentration of a gas in solution and the pressure on the solution. Which of the following options correctly describe the quantities in the Henry's Law equation, given below?Henry's Law: C = kP

k is called the Henry's Law constant for a particular gas/solvent combination. P is the pressure measured in atmospheres. C is the concentration of the gas in moles per liter.