Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Food Analysis > Carbohydrate Analysis > Flashcards

Carbohydrate Analysis Flashcards

1
Q

Carbohydrates contribute to

A

bulk, body, viscosity, stability to emulsions and forms, water holding capacity, browning, flavors, aromas, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Ingested carbohydrates come from

A

plant origins with milk lactose being an exception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

The only carbohydrate that can be absorbed in the small intestine

A

Monosaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Humans can only digest

A

+ Sucrose

+ Lactose

+ Maltooligosaccharides/maltodextrins

+ Starch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Dietary fibers regulate

A

normal bowel function,
reduce the postprandial hyperglycemic response, and may lower serum cholesterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Qualitative analysis ensures

A

that ingredient labels present accurate compositional information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Quantitative analysis ensures

A

added components are listed in the proper order ingredient labels and that amounts of specific components

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

For labeling purposes sugars are defined as

A

the sum of all free monosaccharides and diasaccharides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Examples of sugar alcohols

A

Sorbitol and xylitol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Sample Preparation

A

1) Drying
2) Grinding
3) Extraction (lipids)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Extraction is done with

A

hot 80% ethanol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Reducing sugars are

A

those mono- and oligosaccharides that contain a free carbonyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Methods for Total Carbohydrate

A

Phenol-Sulfuric Acid Method

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Phenol-Sulfuric Acid Method reagents are

A

inexpensive
readily available
stable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Phenol-Sulfuric Acid Method: Absorbance is measure at

A

490 nm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Method for Total Reducing Sugar

A

Somogyi-Nelson Method

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Oxidation of the aldehyde group produces

A

carboxylic acid group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The Somogyi-Nelson method is based on the

A

reduction of Cu (II) to Cu (I) ion by reducing sugars

19
Q

The Somogyi-Nelson method: Absorbance is measured at

A

520 nm

20
Q

Dinitrosalicylic acid method will measure

A

reducing sugars naturally occurring in foods or released by enzymes

21
Q

Munson-Walker Method

A

Oxidation can determined gravimetrically, titration with sodium thiosulfate or potassium permanganate or in the presence of methylene blue

22
Q

Other methods for total reducing sugars

A

+ Dinitrosalicylic acid method

+ Munson-Walker

+ Lane-Eynon

+ Electrolytically

23
Q

Keto groups cannot be _____ thus ketoses are not ________

A

Oxidized; reducing sugars

24
Q

Under alkaline conditions ketoses are

A

isomerized to aldoses

25
Q

Method for specific analysis of mono and oligosaccharides

A

High-Performance Liquid Chromatography (HPLC)

26
Q

HPLC give both

A

qualitative analysis and quantitative analysis

27
Q

HPLC analysis is

A

rapid, can tolerate a wide range of concen. and provides high accuracy and precision

28
Q

HPLC does not require

A

prior derivatization of carbohydrates

29
Q

HPLC does require

A

micron-filter filtration prior to injection

30
Q

Important parameters/principles of HPLC

A

the stationary phase
the mobile phase
the detector

31
Q

Stationary Phases (HPLC)

A

1) Anion-exchange chromatography

2) Normal-phase chromatography

3) Cation-exchange chromatography

4) Reversed-phase chromatography

32
Q

Detectors

A

1) Refractive index detection

2) Electrochemical detection

3) Postcolumn derivatization

4) Precolumn derivatization

33
Q

Gas Chromatography (GC) gas-liquid chromatography GLC provides both

A

qualitative and quantitative analysis of carbohydrates

34
Q

A flame ionization detector is detector of choice for

A

peracetylated
carbohydrate derivatives.

35
Q

Two preparation steps for gas chromatography

A

1) reduction of aldehyde groups to primary alcohol groups

2) conversion of the reduced sugar into a volatile ester

36
Q

The basic principles/important parameters (GC)

A

1) Stationary phase

2) Temperature programming

3) Detection

37
Q

Method of choice for determination of starch employs a combination of

A

enzymes in sequential enzyme-catalyzed reactions

38
Q

Sample preparation for enzyme method

A

Carrez treatment

1) breaks emulsions
2) precipitates proteins
3) absorbs some color

39
Q

Resistant Starch

A

Composed of starch and starch-degradation products that escape digestion in the small intestine

40
Q

Hydrocolloids/Food Gums

A

Added polysaccharides along with the protein gelatin

(Nonstarch polysaccharides)

41
Q

Physical Method

A

1) Microscopy
2) Mass and NIR Transmittance Spectrometry
3) Specific Gravity
4) Refractive Index

42
Q

Major components of dietary fiber

A

1) Cellulose

2) Hemicelluloses

3) Lignin

4) Other nonstarch plant polysaccharides

43
Q

Dietary Fiber

A

the sum of the nondigestible components of a foodstuff or food product

Food Analysis (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions