Culinary Chemistry Exam 1
7 oz its equal to how many cups?
0.875 cups
Arrange the following substances in order from lowest density (1) to highest density (3)
1. Oil 2. Water 3. Sand
Which of the following pH values would represent a STRONGLY acidic solution?
1.0
The dietary calorie(Cal) is equal to
1000 calories
How many teaspoons are in 1/4 cup?
12
Elements in group 2A(2) of the periodic table form ions with a charge of
2+
One cup of kidney beans contains 15 g of protein, 1 g of fat, and 42 g of carbohydrate. How many kilocalories does this sample contain?
240 kcal
fats
3 fatty acid chains and a glycerol
A cheeseburger from a fast food restaurant contains 19 g of fat, 20 g of carbohydrate, and 28 g of protein. How many kcal of energy does the cheeseburger contain? (The caloric values are: 4 kcal/g for carbohydrate, 9 kcal/g for fat, and 4 kcal/g for protein.) Give the answer to 2 significant figures.
360 kcal
The average density of flour is 156 g / cup. How many grams of four are in 2.5 cups?
390 g
Atwater determined the proteins have [x] calories per gram, carbs have [y] calories per gram and fats have [z] calories per gram. (Use the numerical values i.e. 1, 2, 3...)
4,4,9
The FDA allows for _______ % leeway in information reported on nutrition labels.
5
The density of Julie's flour is 145 g per cup. How much does 4 cups weigh?
580g
The pH of pure water is _____.
7
If 30% of Calories should come from fat, how many Calories from fat are required for a 2500 Calorie diet?
750000 calories
The majority of foods we eat have a pH below _____.
8
Structural Formula
A basic arrangement of atoms with respect to each other.
Perspective
A bonding arrangement and 3D spatial orientation
Space filling
A bonding arrangement, spatial orientation and size and orbitals overlap.
Ball and Stick
A bonding arrangement, spatial orientation and size comparison.
Which of the following descriptions of a subatomic particle is correct?
A proton has a positive charge and a mass of approximately 1 amu.
The shape of the water molecule (H2O) is
Bent
Match the chemical to the resulting taste:
Bitter-Alkaloid Salty-Sodium ions Sour-Hydrogen Ions Sweet-Hydrogen bonding of OH groups
Which color has the highest amount of energy?
Blue
carbohydrates
C, H, O compound that is a good source of quick energy.
Which of the following are required to be on a nutrition label?
Calories Fat Calcium Vitamins A and C All of the above
Fats are primarily found in
Cheese, Fish, Oils
What classifies a compound as inorganic?
Does not contain carbon
What is a Calorie?
Energy required to heat 1 kilogram of water by 1 degree celcius
Being sick will never change your ability to taste food.
False
Flour that is 144 grams per cup is more dense than flour that weight 155 g per cup.
False
Tasting "sweet" does NOT require the molecule to be in a specific orientation.
False
Temperature has no effect on how well you can smell food.
False
A chemical process of reflux can be used to determine the amount of ______ in foods.
Fat
Match the correct polarity to the type of molecule.
Fats-non polar Water-polar
Chemical bond
Formed when atoms gain, lose or share electrons
Which of the following are acids (Check all that apply)
HNO3 HCl HNO3
What can cause protein denaturation?
Heat, acid, air, all of the above
What is the correct name for the acid: HCl
Hydrochloric acid
Which of the following shows the correct order for bond strength? (stronger > weaker)
Hydrogen > van der Waals
Which of the following is a physical change?
Ice melts
You're cooking a dish with garlic, balsamic vinegar, and olives. What type of dish are you most likely making?
Italian
Select the correct symbol for the element named. potassium
K
The ______________ method is used to determine the amount of ______________ in a food sample.
Kjeldahl, protein
Non - electrolyte
Material that does not break into ions and does not conduct electricity.
Weak Electrolyte
Material that only partly beaks into ions in solution. Some ions exist as well as entire compound.
The correct chemical formula for magnesium oxide is ____________.
MgO
The correct formula for the compound formed from Mg and S is
MgS.
Which of the following are conjugate acid/base pairs? Check all that apply
NH4+ / NH3 OH / H3O+
Select the correct symbol for the element named. sodium
Na
Electron
Negative
Neutron
Neutral
In the Kjedohl method, [x] is measured to determine the amount of [y] in food.
Nitrogen, Protein
Which of the following is a heterogeneous mixture?
Noodle soup
Hydrogen bonds:
Occur between polar molecules
What did Atwater measure in order to determine calories? (Check all Correct Answers)
Oxygen consumed, Carbon dioxide released, Heat released, Food consumed, Oxygen consumed
Proton
Positive
_________ are known to build and repair tissue.
Proteins
Which of the following is a representation of a hydrogen ion?
Proton H+ H3O+ All of the above
Element
Pure substance made of the same kind of atom
Protein coagulation is when
R groups on the proteins interact with each other causing it to clump together and create and semi soft solid.
The color of objects that we see is the __________ light from the object.
Reflected
Fats are usually _________ at room temperature. (check all that apply)
Solids, Oils
Flavor is a combination of __________.
Taste and smell
Which of the following contributes to the flavor of food?
Taste, Smell-Both
Which of the following is a homogeneous mixture?
Tea
Which of the following are considered mouth feel?
Texture, Spice, Cooling-All of the above
Which of the following is a property of a solid?
The particles have fixed positions and are very close together.
Atom
The smallest particle into which an element can be subdivided
Why is it better to heat foods as rapidly as possible?
To denature and inactivate enzymes present
A non polar molecule has an even distribution of electron density (pulling) around the central atom.
True
Chemist mix acids and alcohols to create new ester which mimic natural flavors.
True
Enantiomers are molecules with non superposable mirror images. Though they have the same molecular formula and bond sequencing, they can exhibit different chemical properties such as smell.
True
Flour is measured by volume instead of mass because it is more accurate representation of the amount of material you have.
True
Hydrogen bonding is the strongest intermolecular force and occurs between the partially positive hydrogen of one molecule and the partially negative charge of a N, O, or F from another molecule.
True
The only things we can smell are volatile chemicals.
True
The visible region of light is found from ~ 400 nm - 700nm
True
Molecule
Two or more atoms bonded together
Which of the following is not an element?
Water
Van der Waals interactions are:
Weak bonds that occur between nonpolar molecules
When mixing a foam into a mixture,
a small amount of the foam should be mixed in before folding in the remainder of the foam
All of the following are properties of vinegar except:
acetic acid has a lower boiling point than water
What can be added to an egg white foam to help stabilize it?
acid
The R group on the amino acid chain can cause the amino acid to be
acidic, hydrophobic, hydrophilic-all of the above
Sour tastes are caused by:
acids in foods
The molecule pictured is a(n) _________ which can give pleasant aromas.
aldehyde
All of the following is true about cooking food except:
all cooking uses the same kind of heat transfer
When amino acids bonds the following occurs:
all of the above- a peptide bond is formed water is released
In an atom, the nucleus contains
all the protons and neutrons.
Emulsifiers:
allow things that mix that do not normally have polar and nonpolar parts interact with polar and nonpolar particles all of the above
Acetic acid is made from:
an alcohol, oxygen and a bacteria
glycogen
animal starch
The smallest particle of an element that retains the characteristics of the element is a(n)
atom
What is the difference between baking soda and baking powder?
baking soda needs an acid to be present in the ingredients baking powder contains a base and a mixture of acids b and c
amylopectin
branched plant starch
Stabilizers have all of the following properties except:
bring the dispersed phase droplets closer together
amino acids
building blocks of protiens
Which of the following is a chemical change?
burning natural gas
The continuous phase in an emulsion:
can be an oil can be water is the container for the dispersed phase all of the above
In regards to heating food to an edible temperature:
continuously cook food until the desired temperature is reached
Which material is best for creating a good egg white foam?
copper
What is true about copper bowls and the formation of egg white foams?
copper bowls allow for greater protein coagulation, copper bowls help form and stabilize the egg white foam- a and c
According to naming rules, the types of compound that use prefixes in their names are
covalent compounds
The atomic size of atoms
decreases going across a period.
Browning reactions:
develop new flavors, occur during the heating of sugar, include Maillard reactions, all of the above
What shouldn't you do when you consume too much capsaicin?
drink water
The ability of an atom to attract the shared electrons in a covalent bond is its
electronegativity
The primary substances of which all other things are composed are
elements
Convection occurs because:
energetic particles collide, transferring energy to the surface of the food
Compounds that are known for making up the majority of pleasurable smells are
esters
The specific heat capacity:
explains why melted cheese on pizza can burn your mouth but the crust will not, is the energy needed to heat 1 g of substance 1 K, varies between materials, all of the above
A Calorie is the amount of energy required to heat 1 grams of water by 1 degree celcius.
false
All store-bought vinegars have the same amount of acetic acid.
false
Baking sodas are complete leavening systems.
false
Bitter, sweet, salty, sour, and umami are the only tastes we can detect.
false
Browning reactions occur under 100 oF.
false
Browning reactions usually occur when food is boiled.
false
Carbon steel is a great cooking material because it is both non-reactive and has great conducting power.
false
Cream and butter both have water as the continuous phase and fat as the dispersed phase.
false
Cream of tartar and sugar should both be added slowly in the middle of the egg white whisking process.
false
Deep frying uses the same type of heat transfer as pan-frying.
false
Emulsions are always an oil dispersed in water.
false
Emulsions occur when anything mixes together.
false
Even though foods cooked by varying methods have multiple forms of heat transfer, the predominant source of heat is always radiant.
false
Food must be cooked for a certain time, and the temperature of the cooked food doesn't matter
false
Hot egg sauces use butter instead of oil so have a greater dispersed volume of fat in them than mayonnaise.
false
In lighter baked goods such as chiffon cakes, the bubbles are created from whisking the oil.
false
In vinaigrettes, oil is dispersed in the water (vinegar) phase.
false
Induction occurs due to a steady electromagnetic field.
false
Mass is often used instead of volume to measure liquids.
false
Nonmetallic solids are the best conductors.
false
Oil is more dense than vinegar.
false
Oligosaccharides taste sweet.
false
Pressure cookers work because they lower the pressure, allowing food to cook at a higher temperature.
false
Smokers use a direct heat source to cook food.
false
Solids are held loosely together but are usually more dense than liquids.
false
Sugar is a very complex carbohydrate.
false
The amount of tastebuds someone has is not related to their ability to be a supertaster.
false
The density of a liquid does not change with respect to temperature.
false
The only fluid that undergoes convection is air
false
The oxygen and hydrogen atoms in carbohydrates are present in the form of water.
false
Vinegar is basic.
false
Water molecules repel each other.
false
When proteins are denatured, the amino acids change.
false
The valence electrons are the electrons that are
farthest from the nucleus and available for chemical reactions.
Temperature is an important part of making an emulsion because of all of the following except:
fast moving particles create tiny droplets
Why do fats need to be kept out of egg white foams?
fats will interact with the protein fats prevent air from interacting with the protein both b and c
When boiling:
food is cooked at a constant temperature
When baking:
food is cooked by the air food is cooked by the heat from the walls of the oven both a and b
Esters smell:
fruity
How many electrons will chlorine gain or lose when it forms an ion?
gain 1
Identify the metalloid in the following list.
germanium
All of the following is true about bowls for whisking egg whites except:
glass bowls help stabilize the foam
On the periodic table of the elements, each vertical column is called a(an) _____ and each horizontal row is called a(an) _____.
group; period
An ionic compound
has a net charge of zero.
Which of the following is a physical property of both liquids and gases?
has randomly arranged particles
radiation
heat in the form of waves
conduction
heat is transferred through direct contact with the heat source
induction
heat is transferred through magnetism
convection
heat is transferred through the movement of fluids
Cream of tartar:
help denature the proteins is an acid allows for more protein coagulation all of the above
A pH ______________ 7 indicates a basic solution.
higher than
Which of the following is a physical change?
ice melts
Valence electrons are electrons located
in the outermost energy level of an atom
The boiling point of a syrup _______________ with increasing concentration of sugar
increases
When an ACID ionizes in water, the number of hydronium ions in the solution _____ and the value of the pH _____.
increases, decreases
Protein coagulation:
is a result of protein denaturation results when proteins bump into each other is why egg whites will form a foam all of the above
Mayonnaise:
is an oil in water emulsion
All of the following are examples of foams except:
jello
proteins
large C, H, O, N compound that folds into due to attractions and repulsions between amino acids.
colloid
large particles that will not settle out and will scatter light showing their presence.
amylose
linear plant starch
How can you determine what ingredients to use with what you have?
look at seasoning packets, search online to see what is commonly used with those ingredients, add a small amount of the ingredient to a small bowl of the dish and try it All of the above
A pH ______________ 7 indicates an acidic solution.
lower than
The compound MgCl2 is named
magnesium chloride.
Strong Electrolyte
material that completely breaks into ions and conduct electricity.
Mark all of the true statements about metals below:
metals are good conductors, metals have loose electrons that behave as a fluid, metals will heat up and cool down quickly
The _________ dispersed phase is added, the ___________ viscous the emulsion.
more, more
The correct name of the compound NCl3 is
nitrogen trichloride.
Phospholipids:
occur in proteins create a lipid bilayer can act as emulsifiers all of the above
Oil and water don't normally mix because:
oil is a nonpolar liquid and water is a polar liquid polar and nonpolar liquids do not mix both b and c
Our tongues behave as ____________.
pH detectors taste receptors chemical detectors all of the above
Which one of the following properties describes a liquid?
particles are close together and move randomly
Suspension
particles are large and settle out of solution
Which of the following is not a characteristic of the solid state?
particles are moving very fast
What is the biggest indicator that you will cook a pleasing dish?
picking good ingredients
Aldehydes smell:
plant-like
A group of covalently bonded atoms that has an overall electrical charge is called a(n)
polyatomic ion.
Maillard reactions:
produce complex flavors due to amino acids in the proteins
Besides water, what do egg whites consist of?
proteins
The atomic number of an atom is equal to the number of
protons
The most important variable for good flavor is the _________ of ingredients you use.
quality
When grilling, what types of heat transfer can occur?
radiant convection Both of the above
Pan-frying:
requires a balance between cooking the inside of the food enough without burning the outside, allows uniform heat contact when an oil is used, allows more flavor development with the addition of oil and browning reactions, all of the above
What can be added to neutralize bitterness in foods?
salt
What property of salts allows them to penetrate our foods?
salt is made of smaller atoms
Solution
small solute particles that can not be seen and do not separate out
What type of cooking material gets "the closest" to being both chemically unreactive and a good conductor?
stainless steel with a copper plate
Amines smell:
stinky/rotten
Are the bonds that hold water molecules together stronger or weaker than the bonds that hold fats together?
stronger
A solution with a pH of 1.5 is ___________________.
strongly acidic
Which of the following elements is a metal?
strontium
The flavors, odor and "lacrimator" affect of onions all come from the element ____________.
sulfur
Flavor is a combination of ________.
taste and smell
An ionic bond results from
the electrical attraction between a cation and an anion.
When making mayonnaise:
the ingredients should be at room temperature, acid is added to kill bacteria, the oil to water ratio is critical, all of the above
Acetic acid exists in two forms: the dissociated and intact molecule. Which form is more volatile and more aromatic?
the intact molecule
When egg whites are whipped:
the proteins are denatured by air
"Double Acting" baking powder refers to:
the release of gases at the beginning of mixing the release of gases while the mixture is heated both a and b
What happens when table salt, NaCl, is put into water?
the sodium and chloride dissociate ions are formed b and c
In a solution, the solvent is:
the substance in the greatest amount
Caramelized sugar has all of the following characteristics except:
the sugar is now sweet and odorless
All of the following is true about heat and temperature except:
the terms can be used interchangeably in cooking
The dispersed phase in an emulsion is all of the following except:
the water in an "oil and water" emulsion
Eggs can be used as emulsifiers because:
they are an emulsion themselves, they contain proteins that behave as stabilizers, they add more flavor to the sauce, all of the above
All of the following is true about vinaigrettes except:
they can be made with two kinds of oils
Which of the following is an element?
tin
All of the following is true about why tiny droplets of dispersed phase are desired except:
tiny droplets cause a thinner consistency
All of the following are mistakes cooks make when making an emulsified sauce except:
too much continuous phase is used
All of the following is true about adding the right amount of leavening agent except:
too much leavening will leave the food flat and dense
A gas is mostly empty space.
true
A solution is created by a solute in a solvent.
true
Although ceramics are poor conductors, they are a versatile type of cookware.
true
Alton Brown highly recommends that if vegetable oil is unavailable for cupcakes, not to use any other kind of oil because the flavor will be affected.
true
Amino acids are a biological polymer. They contain repeating units.
true
Amino acids have both hydrophobic and hydrophilic regions.
true
An air pocket inside the egg can be used to determine if an egg is good or bad.
true
As a water boils (goes from liquid to gas) the temperature does not change.
true
Baking powder contains both acids and bases in the powder.
true
Cast iron materials work great in high temperature cooking.
true
Certain types of cooking, such as boiling, do not allow browning reactions to occur because they do not get hot enough.
true
Chemical leaveners produce carbon dioxide gas.
true
Cooking a material through the use of a fluid is called convection.
true
Copper is an excellent conductor and is non-reactive with food only when coated with tin or stainless steel.
true
Dissociation means to separate into ions.
true
Electrons are loosely held in metals, allowing them to conduct heat
true
Even though radiation occurs in all types of cooking, only radiation at high temperatures is a useful type of heat transfer.
true
Fats and carbohydrates are mainly passive forms of stored energy.
true
Foams contain tiny air bubbles surrounded by proteins.
true
Glucose is also known as blood sugar.
true
Hydrogen bonding between water molecules causes them to be more dense.
true
In a covalent bond, electrons are shared between two atoms.
true
Items that feel "warm" can be said to be emitting infrared radiation.
true
Maillard reactions occur between a carbohydrate and an amino acid.
true
Microwaves cause water molecules to move faster, heating up the food.
true
Mustard is added to mayonnaise to stabilize the emulsion.
true
Oil and water do not mix because they have different forces holding them together.
true
Pan-frying allows for browning reactions to occur due to the high temperature cooking.
true
Proteins are made of lots of different kinds of amino acids
true
Proteins are unlike carbohydrates and fats because they are "active machinery of life" in which they move whole animals.
true
Sodium bicarbonate is the base in baking sodas and powders.
true
The abbreviation for cup is C.
true
The ability to supertaste is genetic
true
The pH of pure water is 7.
true
Vinegar has both hydrophobic and hydrophilic regions.
true
Vinegar is produced from alcohol fermentation.
true
Water can act like an acid or a base.
true
Water is a polar molecule.
true
Water is considered the universal solvent.
true
When something boils at a lower temperature, it takes longer for the food to cook completely.
true
When sugar is caramelized, the taste, smell, and color changes.
true
When using the seasonal method of cooking, it is OK to use frozen vegetables in a bind.
true
While non-stick aluminum is both conductive and non-reactive with food, it can only be used up to certain temperatures.
true
The abbreviation for teaspoon is
tsp
A dipole - dipole interaction occurs between
two polar molecules
All of the following is true about Umami except:
umami is the strongest of the primary tastes
Which of the following is not an element?
water
When steaming food:
water vapor condenses onto food, transferring energy more conduction occurs within the food than in an oven Both a and b
All of the following is true about our ability to smell except:
we cannot detect volatile chemicals
A polar material will make a solution with a non-polar material.
wrong
Which of the following is true about yeast? Choose all that apply.
yeast produces bubbles in doughs in batters yeasts have different flavors depending on the environment hard water is the best kind of water for yeast
Will carbon dioxide dissolve in water?
yes
Will sucrose dissolve in water?
yes
