carbs

Question 1

monosaccharide

Answer 1

Monosaccharides are the fundamental units because they are not hydrolyzed by acid to form a smaller unit.

Question 2

disaccharide

Answer 2

consist of two simple sugarslinked by a covalent

glycosidic bond

Question 3

oligosaccharide

Answer 3

consist of 3 to 10 monosaccharides linked together by glycosidic bonds

Question 4

what is the functionality of monosaccharides

Answer 4

Coloring agents (caramel color)
Production of flavors (caramelization)

Question 5

what is the functionality of a polysach.

Answer 5

Thickening agents 
Gelling agents
Emulsion stabilizers
Water holding/ binding agents
Anticaking agents
Edible films
Encapsulate flavors

Question 6

complete

Their actual conformation is … in their crystalline state and
predominantly cyclic in solution

Answer 6

cyclic

Question 7

Cyclization is due to the formation of internal … and

…

Answer 7

hemiacetals and hemiketals

Question 8

hemeacetal formation in glucose forms a

Answer 8

pyranose ring

Question 9

hemiketal formation in fructose form a

Answer 9

furanose ring

Question 10

mutaotation

Answer 10

is the result of the cyclic form opening up and recyclizing, coming to equilibrium with its anomer.

Question 11

which is the most comon test for reducing sugars

Answer 11

fehling’s test

Question 12

The disaccharide maltose a reducing sugar while the

disaccharide sucrose is a non-reducing sugar - why?

Answer 12

Because even when 2 molecules of maltose are bind together they can open up however fructose cannot do this and so it is not a reducing sugar

Question 13

which are the 2 ways that water can be elimiated from sugar

Answer 13

1. by reaction of tehir hydroxyl groups

2. elimination of water grom within a sugar molecule, leading to the formation of higly unstaurated ring structure

Question 14

A common intermediate formed during caramelization reactions by
dehydration is

Answer 14

hydroxymethylfurfural (HMF)

Question 15

what are the 2 categories of browning reactions

Answer 15

(1) oxidative browning

(2) non-oxidative browning

Question 16

caramelization reaction used to producde

Answer 16

flavor, color

Question 17

carame flavor and color are made of

Answer 17

flavors - sucrose

color- glucose

Question 18

what is an amadori rearrangement

Answer 18

schiff base to amadori compound

Question 19

at higher temperature in the maillard reacion , the major reactions will be

Answer 19

dehydration and fragmentation

Question 20

strecker degration

Answer 20

subcomponent of maillard reaction. Involves free amino acids produced by meaillard reacion or caramelization

Question 21

which is the most sweet of the sugars and the less

Answer 21

most- fructose

less- lactose

Question 22

true or false

The least sweet the less soluble

Answer 22

true

Question 23

which sugar is an exception int he sence of sweetnes of the sugar alcohols

Answer 23

xylitol

Question 24

the properties of polysaccharide are a fucntion of

Answer 24

their sugar/chemical makeup
• the presence of unique functional groups
• their molecular weight and degree of branching
• a combination thereo

Question 25

wha are the unique porperties of starch

Answer 25

thickening, texture

Question 26

starch is made up of

Answer 26

D glucose which are divided in amylose (alpha 1-4 linkages) and amylopectin (alpha 1-6)

Question 27

explain starch granules

Answer 27

granyles are characterisic of the starch source. The starch is isolated and it is white. It contains granules that are made of amylose and amylopectin

Question 28

what happens in gelatinization

Answer 28

starch and water are heated and it causes teh granules to swell. The viscocity increases

Question 29

what are the variables that occur in the starch

Answer 29

concentration of starch • The amylose:amylopectin ratio of the starch • The average molecular weight (chain length) of the starch • The rate of cooling • The presence of other components in solution

Question 30

true or false Amylopectin is a highly branched water-dispersible macromolecule

Answer 30

true

Question 31

retrogration

Answer 31

continued Hbonds formation between starch molecules

Question 32

what are the 2 problems with retrogration

Answer 32

1. texture changes | 2. syneresis may occur = the gel tightens up that it starts to exude water

Question 33

factors affecting behaviours of starches in complex food system

Answer 33

pH, ionic strengh, proteins,

Question 34

pre gelatinized strach

Answer 34

Starches granules are heated below the gelatinization temperature of the starch, causing them to swell Causes some disorganization of the starch granule- making it dispersible in cold water and requires less heat or time to develop viscosity

Question 35

acid modified starches

Answer 35

Produced by holding starch just below its gelatinization temperature in an acidic medium Acid is used to partially and randomly hydrolyze the glycosidic linkage in the starch granule without breaking up the INTEGRITY of the granule per se.

Question 36

cross linked starches explain

Answer 36

Maximum viscosity is normally reached when the granules are swollen extensively but still intact - however, swollen granules normally break down with subsequent shear. Can hold starch granules together by cross-linking starch chemically so that the swollen granule retains its integrity

Question 37

what are the 2 types of starch conversion

Answer 37

dry pyroconversion and acid hydrolysis

Question 38

what is pyroconversion

Answer 38

Starch granules are sprayed with dilute HCl and subjected to relatively high temperatures

Question 39

what are the 3 products that are produced by pyroconversion

Answer 39

white dextrins, yellow dextrins, british gums

Question 40

white dextrins

Answer 40

can be Under conditions of high moisture, high acid, and relatively low temperature, hydrolysis predominates.

Question 41

yellow dextrins

Answer 41

Lower moisture, moderate acid, higher temperature. Color due to caramelizatio

Question 42

british gums

Answer 42

Little or no acid used - high temp. Dark color. Viscous and capable of forming a stiff gel

Question 43

what are the 4 available enzymes to broke starch

Answer 43

alpha amylase beta amylase glycoamylase pullulanase

Question 44

what does alpha amylase does

Answer 44

attack the starch everywhere except the alpha 1- 6 branch. produce oligosaccharide

Question 45

what does beta amylase does

Answer 45

attacks the non reducing end of the starch. Produces maltose! Also develop sweetness rapidly

Question 46

what does the glucoamylase does

Answer 46

remove single glucose units form the non reducing end of starch and to split maltose into 2 glucose units

Question 47

what pullulanase does

Answer 47

Take care of the branch

Question 48

High-fructose corn syrups are similar to ... and are in direct competition with sucrose, which is commonly inverted (e.g., using the enzyme invertase) to stabilize its sweetness in acidic environments )

Answer 48

invert syrups

Question 49

Cellulose is often accompanied by other carbohydrates (hemicelluloses and pectic substances) and ... to form the structural components of most plant tissues

Answer 49

lignin