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Vitamin Losses During
Food Storage and
Processing
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Vitamin Losses During Food Storage and Processing
Contents:
1. Introduction
2. Fat-soluble vitamins
3. Water-soluble vitamins
4. Simultaneous analysis of fat-soluble vitamins
5. Analysis of vitamin C
6. Conclusion
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Vitamin Losses During Food Storage and Processing
Introduction
Introduction
Vitamins :
Are organic compounds.
Are indispensable in very small amounts in the diet.
They have specific and individual functions to promote
growth or reproduction, or to maintain health and life.
They regulate metabolic processes, control cellular
functions, and prevent diseases, such as scurvy and
rickets.
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Vitamin Losses During Food Storage and Processing
Introduction
Introduction
Vitamins are unstable in foods.
Processing and cooking conditions cause vitamin
loss. The losses vary widely according to cooking
method and type of food.
Vitamin degradation depends on specific
parameters during the culinary process, e.g.,
temperature, oxygen, light, moisture,pH, and
obviously length of exposure.
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Vitamin Losses During Food Storage and Processing
Fat-soluble vitamins
Fat-soluble
vitamins
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Vitamin Losses During Food Storage and Processing
Fat-soluble vitamins
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Vitamin Losses During Food Storage and Processing
Fat-soluble vitamins
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Vitamin Losses During Food Storage and Processing
Fat-soluble vitamins
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Vitamin Losses During Food Storage and Processing
Fat-soluble vitamins
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Vitamin Losses During Food Storage and Processing
Water-soluble vitamins
Water-soluble
vitamins
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Vitamin Losses During Food Storage and Processing
Water-soluble vitamins
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Vitamin Losses During Food Storage and Processing
Water-soluble vitamins
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
Due to the nutritional importance of the vitamins
several analytical methodologies have been
developed for determination of these substances
in food:
Spectrophotometry
Spectroflurorimetry
Voltametry
Chromatography
…
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Simultaneous analysis of fat-soluble vitamins
Why chromatography?
To determine more than one vitamin, the
analytical method should be able to determine
multi-components in complex samples.
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Simultaneous analysis of fat-soluble vitamins
BUT
This method cannot be considered green,
including the ones to determine fat-soluble
vitamins, due to the utilization of several
organic solvents as mobile phase.
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Simultaneous analysis of fat-soluble vitamins
strategy
To decrease the amount of toxic organic solvent,
normally utilized in the chromatographic
determination of fat-soluble vitamins.
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
Simultaneous analysis of
fat-soluble vitamins
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Simultaneous analysis of fat-soluble vitamins
The stationary phase is a C18 column due to its
popularity.
As the main goal was to develop green
chromatographic method, all reagents selected as
mobile phase component should be as nontoxic as
possible.
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
Structure of the fat-soluble vitamins
vitamin A
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
Structure of the fat-soluble vitamins
vitamin E
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
Structure of the fat-soluble vitamins
vitamin D3
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
Structure of the fat-soluble vitamins
vitamin K1
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Simultaneous analysis of fat-soluble vitamins
The vitamins A, E, D3 and K1 are
hydrophobic.
High affinity by the selected stationary phase (C18 group)
Elution of Fatsoluble vitamins
1. Usage of high concentrations of
methanol and acetonitrile
2. Use of micelar medium
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Simultaneous analysis of fat-soluble vitamins
Micelar medium :
The anionic SDS surfactant almost did not present
absorption in the UV region and was selected as
mobile and stationary phase modifier.
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SDS : sodium dodecyl sulphate
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
SDS in concentrations higher than the critical micelar
concentration (CMC, 0.24% (w/v)) as mobile phase :
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Effect of the SDS in the separation of fat-soluble vitamins.
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Vitamin Losses During Food Storage and Processing
Simultaneous analysis of fat-soluble vitamins
SDS and ethanol in the mobile phase :
Effect of the ethanol in the chromatographic separation of fat-soluble vitamins.
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Simultaneous analysis of fat-soluble vitamins
SDS and n-butyl alcohol in the mobile phase :
Effect of the butyl alcohol in the chromatographic separation of fat-soluble vitamins.
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Simultaneous analysis of fat-soluble vitamins
SDS and n-butyl alcohol in the mobile phase :
It was possible to elute all the analytes in 70 min.
Optimization of the green chromatographic method:
to improve the analytical frequency
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Simultaneous analysis of fat-soluble vitamins
pH
Constant
Temperature
Experimental
conditions
Mobile phase flow rate
SDS concentration
Factorial
Experiment
Butyl alcohol concentration
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Simultaneous analysis of fat-soluble vitamins
Conditions of the factorial experiment to optimize the
determination of the fat-soluble vitamins A, E, D3 and K1
Experiment
Butyl alcohol
SDS
Flow rate
1
10.0% (v/v)
1.50% (w/v)
1.5 mLmin−1
2
15.0% (v/v)
1.50% (w/v)
1.5 mLmin−1
3
10.0% (v/v)
15.0% (w/v)
1.5 mLmin−1
4
15.0% (v/v)
15.0% (w/v)
1.5 mLmin−1
5
10.0% (v/v)
1.50% (w/v)
2.0mLmin−1
6
15.0% (v/v)
1.50% (w/v)
2.0mLmin−1
7
10.0% (v/v)
15.0% (w/v)
2.0mLmin−1
8
15.0% (v/v)
15.0% (w/v)
2.0mLmin−1
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Simultaneous analysis of fat-soluble vitamins
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Effect of the mobile flow rate, butyl alcohol and SDS concentrations in
the chromatographic separation of fat-soluble vitamins.
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Simultaneous analysis of fat-soluble vitamins
Result :
Experiment 8 led to the best result.
Quantifying the fat-soluble vitamins was possible in
25.0 min with retention times of 4.0, 9.6, 13.0 and
22.7 min to D3, A, E and K1 vitamins, respectively.
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Simultaneous analysis of fat-soluble vitamins
Determination of fat-soluble vitamins with the proposed green
chromatographic method. The results are expressed in mg L−1 ±S.D.
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Simultaneous analysis of fat-soluble vitamins
Comparison of green and conventional chromatography
Determination of fat-soluble vitamins in food and pharmaceutical supplement samples by the
proposed green chromatographic method and by the conventional one
The results are expressed in mg g−1 ±R.S.D.
a : Liquid sample and the results are expressed in mg L−1.
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Analysis of vitamin C
Analysis of
vitamin C
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Analysis of vitamin C
Vitamin C is considered as the most important
water-soluble antioxidant.
The current RDA for ascorbic acid is suggested to
be 100–120 mg/day to achieve cellular saturation
and optimum risk reduction of heart diseases,
stroke and cancer in healthy individuals.
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RDA : recommended daily acceptance
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Vitamin Losses During Food Storage and Processing
Analysis of vitamin C
Evaluation of the effect of time and temperature
on the content of vitamin C of two different
brands of pure orange juice by HPLC
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Analysis of vitamin C
Changes in the content of vitamin C measured by HPLC in orange juices during 6 months
of storage at 18, 28 and 38 ºC (mg/L)
Months of storage
18 ºC
28 ºC
38 ºC
Orange juice 1
0
408.5
2
385.4
336.6
265.6
4
354.0
302.0
145.1
6
333.0
283.6
83.5
Orange juice 2
0
361.5
2
340.2
311.3
202.4
4
303.5
270.4
127.4
6
280.2
244.2
63.1
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Analysis of vitamin C
Evaluation of the antioxidant activity of the
orange juices by FRAP assay
Fe3+
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antioxidant
Fe2+
FRAP : ferric reducing antioxidant power
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Vitamin Losses During Food Storage and Processing
Analysis of vitamin C
Changes in the antioxidant activity (FRAP mM) in orange juices during 6
months of storage at 18, 28 and 38 ºC
Months of storage
18 ºC
28 ºC
38 ºC
Orange juice 1
0
7.5
2
7.2
6.5
5.5
4
6.4
6.0
4.6
6
6.1
5.1
3.3
2
6.9
6.1
5.5
4
6.0
5.4
4.4
6
5.4
4.5
3.0
Orange juice 2
0
7.1
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Analysis of vitamin C
Changes in (A) FRAP value in orange juice
upon storage at: 18 ºC , 28 ºC and 38 ºC
Changes in (B) vitamin C in orange juice upon
storage at: 18 ºC , 28 ºC and 38 ºC
Changes were calculated as the percentage of the values obtained for fresh juice.
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Conclusion
Conclusion :
Vitamin A is stable under an inert atmosphere;
however,it rapidly loses its activity when heated
in the presence of oxygen, especially at higher
temperatures.
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Conclusion
Conclusion :
Retention of vitamin A in vegetables:
household microwave steaming>frying >
cooking without addition of water > cooking with
the use of a large amount of water
There were no significant differences in vitamin A
concentration among raw, pasteurized, and
cooked milks.
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Conclusion
Conclusion :
Vitamin D is susceptible to the alkaline pH range,
light, and heat .
No losses were found during pasteurization and
sterilization of milk or during production of dried
or evaporated milk.
Fat content is probably the crucial factor affecting
retention during culinary treatment.
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Conclusion
Conclusion :
Vitamin E is unstable in the presence of oxygen, light,
and even some unsaturated fats.
Retention of vitamin E in meats:
roasting > frying > boiling
The losses of vitamin E in egg yolk during cooking:
preparation, particularly by more drastic methods.
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Conclusion
Conclusion :
Vitamin K is destroyed by sunlight and decomposed
by alkalis.
More vitamin K was retained when microwave
heating was used.
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Conclusion
Conclusion :
Cooking losses of vitamin C depend on the degree
of heating, leaching into the cooking medium,
surface area exposed to water and oxygen, pH,
presence of transition metals, and any other factors
that facilitate oxidation .
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Conclusion
Conclusion :
Retention of vitamin C in vegetables:
Steaming>microwave technique>stir-frying with oil>
pressure-cooking>conventional cooking, starting
with boiled water> starting with cold water
Thawing before cooking causes more vitamin C loss.
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Conclusion
Conclusion :
Retention of vitamin B in meats:
microwave>frying>parching>steaming>boiling
Marinading of fish is the most damaging process.
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References :
1. Journal of Food Composition and Analysis 19 (2006) 252–276
2. Talanta 75 (2008) 141–146
3. Journal of Food Composition and Analysis 20 (2007) 313–322
4. Spectrochimica Acta Part A 65 (2006) 802–804
5. Food Chemistry 100 (2007) 1220–1222
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