Proximate Analysis Flashcards

1
Q

What is Food Analysis?

A

development, application and study of analytical methods for characterizing foods and their constituents

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

What’s the equation for % Moisture?

A

(wet weight - dry weight) / (wet weight) x 100%

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

What’s the equation for Ether Extract ( % Crude/Estimated Fat)?

A

(weight of ether extract) / (wet weight of sample) x 100%

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

Is dry weight over or underestimated? Why?

A
  • underestimated
  • loss of vitamins and minerals during drying
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Is Ether Extract ( % Crude/Estimated Fat) over or underestimated? Why?

A
  • overestimated
  • other things are dissolved by solvent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What’s the equation for % Ash (Mineral Content)?

A

(weight of ash) / (wet weight of sample) x 100%

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

What’s the equation for % Protein (Nitrogen)?

A

[ (N in sample)(6.25) / (wet weight of sample) ] x 100%

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

Is % Protein (Nitrogen) over or underestimated? Why?

A
  • overestimated
  • assumes all proteins are 16% nitrogen
  • there are additional sources of nitrogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What’s the equation for % Crude Fiber?

A

[(weight of ash + crude fiber) - (weight of ash)] / (wet weight of sample) x 100%

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

What’s Crude Fiber?

A
  • mostly ligand and cellulose (insoluble fibers)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Does % Crude Fiber over or underestimate Dietary Fiber?

A

underestimates

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

What are Soluble Fibers?

A
  • pectins, gums, mucilages
  • form a gel in water (dissolve)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are Insoluble Fibers?

A
  • cellulose, lignin, hemicellulose
  • remain intact in water (don’t dissolve)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What’s Dietary Fiber?

A

describes all fiber (insoluble and soluble)

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

What’s the equation for % Nitrogen Free Extract (Digestible Carbohydrate Content)?

A

100% - (% moisture + % crude fat + % ash + % crude protein + % crude fiber)

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

What are the 2 accurate ways to measure fiber?

A
  • Van Soest Method
  • Southgate Method
17
Q

What’s the Van Soest Method? What are its strengths?

A
  • method of measuring fiber
  • differentiates insoluble from soluble fibers
  • determines fermentability
  • used for animal feeds
18
Q

What’s the Southgate Method? What are its strengths?

A
  • method of measuring fiber
  • provides info on sugars and starches
  • provides info on insoluble fibers
  • used for human nutrition