Week8-Course2

Question 1

Define one calorie

Answer 1

amount of heat required to increase the temperature of 1gram of H2O by 1°C (from 14.5 to 15.5 ° C).

Question 2

1 cal = ___ joules

Answer 2

4.184

Question 3

Why would determining energy content of a food not be reliable if it only done by the bomb calorimeter

Answer 3

doesn’t take into account digestibility

Question 4

How can you estimate the energy content of food if you are not using the bomb calorimeter?

Answer 4

You use analytical chemistry to estimate the content of food and you multiply the content by the standard values.

Question 5

T or F : for fat 9kcal/g is an average value of the energy content but it varies

Answer 5

T

Question 6

T or F : sugar alcohol are non-nutritive sweetners

Answer 6

False, they are nutritive sweetners because they provide 1.5-3kcal/g

Question 7

T or F : artificial sweetners can interact with water like real sugar so they can be used for baking

Answer 7

F, the sugar alcohol can be used for baking because they bind water but not the artificial sweetners

Question 8

Why sugar alcohol can be used for baking?

Answer 8

because they can bin with water by making hydrogen bonds and they provide most of the functional properties of sugars

Question 9

What a.a. contain aspartame? How are they bounded?

Answer 9

methyl ester of a dipeptide (phenylalanine +

aspartic acid

Question 10

What is the alternative really similar to aspartame that phenylketonuria patients can consume? Why?

Answer 10

Neonatame, because it is the same molecule as aspartame but with a neohexyl attached so the peptidic bound can’t be broken so the phenylalannine is not released

Question 11

What is the sweetning power of neonatame?

Answer 11

7000-13000

Question 12

What is the sweetning power of aspartame?

Answer 12

200

Question 13

What is the sweetning power of acesulfame-K

Answer 13

200

Question 14

What is the molecule of sucralose?

Answer 14

sucrose molecule with three chlorine instead of the hydroxyl groups

Question 15

What is the sweetning power of sucralose

Answer 15

600

Question 16

Name two fat replacers

Answer 16

olestra

simplesse

Question 17

What is simplesse?

Answer 17

fat replacer made of microparticulated milk and/or egg-white proteins

Question 18

Why is simplesse not suitable for frying?

Answer 18

Because made of egg-white proteins and they are going to denature

Question 19

T or F : sugar alcohol behave exactly the same as sugars?

Answer 19

False, they have most of the functional propoerties of sugars but do not behave the same as sugars

Question 20

What is olestra?

Answer 20

Fat replacer, sucrose molecule with 6-8 hydroxyl groups are esterified with fatty acids

Question 21

What are the kind of fat replacers really used in industries right now

Answer 21

carbohydrates based fat replacers because they act as fat in food products

Question 22

T or F: Carbohydrates: both sugars and starch assist the body in utilizing fats
more efficiently by producing organic acids that are required to
convert fats fully to CO2 and water

Answer 22

T, the carbohydrates are necessary for the conversion of glucose to pyruvate (organic acid) that is necessary for the conversion of acetyl coa to CO2 and energy in the TCA cycle

Question 23

T or F :proteins are the main source of nitrogen and amino acids
for the body’s synthesis of tissue and other protein- or nitrogencontaining
constituents

Answer 23

T

Question 24

What determine the biological value or nutritional quality of protein?

Answer 24

The presence of essential amino acids and their balance and the digestibility

Question 25

What essential amino acid is lacking in cereals

Answer 25

lysine

Question 26

What essential amino acid is lacking in legumes

Answer 26

methionine

Question 27

Why are animal used in the evaluation of a protein's quality?

Answer 27

Because the balance of amino acid (composition of the protein) is not enough to evaluate the quality, the protein digestibility needs to be taken into account

Question 28

Why is the plant based protein of low quality?

Answer 28

Because of the poor essential amino acid profil content (lacking either methionine or lysine) and the low digestibility

Question 29

T or F : if you only consume gelatine as a source of protein you will loose weight

Answer 29

True, because low essential amino acid content will make your body catabolise body's protein content

Question 30

What is the PER?

Answer 30

Protein efficiency ratio (PER) : a measure of the animal's weight gain per gram of a certain protein consummed.

Question 31

Higher is the PER, higher is the _______

Answer 31

protein quality

Question 32

What is the BV?

Answer 32

Biological value, it measure the protein quality using the nitrogen retention by measuring the protein consummed - the nitrogen excreted

Question 33

What is the NPU ?

Answer 33

Net protein utilization, it is the biological value (BV) times the digestibility factor

Question 34

What is the NPV

Answer 34

it is the net protein value (NPV) times the % protein in food

Question 35

T or F : Many food processing operations reduce the vitamin content or availability in foods

Answer 35

T

Question 36

What are the fat soluble vitamins?

Answer 36

A Retinol D calciferol E alpha-tocopherol K Phylloquinone

Question 37

What are the water soluble vitamins?

Answer 37

C ascorbic acid B vitamins (1,2,3,5,6,7,9,12) and choline

Question 38

T or F : hydrosoluble vitamins are more stable than liposoluble so they are less affected by oxidation

Answer 38

False it is the inverse that is true

Question 39

T or F : Dramatically reduced fat intake can lead to a shortage of fat-soluble vitamins

Answer 39

True

Question 40

T or F : vitamin A is only found in animal derived products

Answer 40

True, but the precursor (or pro-vitamin) beta-carotene is found in plant

Question 41

What are the roles of retinol, retinal and retinoic acid?

Answer 41

Retinol: Strengthens mucous membranes; keeps skin flexible Retinal: Plays a fundamental role in vision: vitamin A deficiency affects night vision Retinoic acid: Regulates gene expression/protein production in cell nucleus

Question 42

Retinol is a

Answer 42

alchohol

Question 43

Retinal is a

Answer 43

aldehyde

Question 44

Retinoid acid is a

Answer 44

acid

Question 45

Cleaving one molecule of the beta-carotene gives to molecules of ____

Answer 45

retinol

Question 46

Complete : vitamin D is synthesized from | ____ upon exposure to ____ specifically ___

Answer 46

cholesterol and other sterols to sunlight UVB

Question 47

Complete : vitamin D is involved in the absorption of ____ and ___ from the

Answer 47

calcium and phosphorus from the kidneys

Question 48

T or F : Raw milk is a rich source of vitamin D

Answer 48

FALSE, vitamin D is added to milk in the processing.

Question 49

What are good food sources of vitamin D?

Answer 49

fish, liver, dairy products (added) and eggs

Question 50

T or F : Vitamin E is present in most unprocessed vegetable oils but may be lost during processing and refining.

Answer 50

True

Question 51

What is specific molecule in the tocopherol family that has the highest antioxidant funciton

Answer 51

delta-tocopherol

Question 52

T or F : Vitamin K is also synthesized by microorganisms in the intestinal tract.

Answer 52

True

Question 53

T or F : it is very rare to notice the deficiency of vitamin K because it is produced by the microorganism in the colon by fermenting fiber

Answer 53

True

Question 54

T or F : protein quality can be evaluated on the basis of amino acid composition.

Answer 54

F, it need to take into account the digestibility of the protein source so animal studies are necessary.