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2 Vitamin Losses During Food Storage and Processing 16-June-2008

3 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 Vitamin Losses During Food Storage and Processing 16-June-2008

4 Vitamin Losses During Food Storage and Processing 16-June-2008 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. Introduction

5 Vitamin Losses During Food Storage and Processing 16-June-2008 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.

6 Vitamin Losses During Food Storage and Processing Fat-soluble vitamins 16-June-2008 Fat-soluble vitamins

7 Vitamin Losses During Food Storage and Processing 16-June-2008 Fat-soluble vitamins

8 Vitamin Losses During Food Storage and Processing 16-June-2008 Fat-soluble vitamins

9 Vitamin Losses During Food Storage and Processing 16-June-2008 Fat-soluble vitamins

10 Vitamin Losses During Food Storage and Processing 16-June-2008 Fat-soluble vitamins

11 Vitamin Losses During Food Storage and Processing Water-soluble vitamins 16-June-2008 Water-soluble vitamins

12 Vitamin Losses During Food Storage and Processing 16-June-2008 Water-soluble vitamins

13 Vitamin Losses During Food Storage and Processing 16-June-2008 Water-soluble vitamins

14 Vitamin Losses During Food Storage and Processing 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 … 16-June-2008 Simultaneous analysis of fat-soluble vitamins

15 Vitamin Losses During Food Storage and Processing Why chromatography? To determine more than one vitamin, the analytical method should be able to determine multi-components in complex samples. 16-June-2008 Simultaneous analysis of fat-soluble vitamins

16 Vitamin Losses During Food Storage and Processing 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. BUT 16-June-2008 Simultaneous analysis of fat-soluble vitamins

17 Vitamin Losses During Food Storage and Processing To decrease the amount of toxic organic solvent, normally utilized in the chromatographic determination of fat-soluble vitamins. strategy 16-June-2008 Simultaneous analysis of fat-soluble vitamins

18 Vitamin Losses During Food Storage and Processing 16-June-2008 Simultaneous analysis of fat-soluble vitamins Simultaneous analysis of fat-soluble vitamins

19 Vitamin Losses During Food Storage and Processing 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. 16-June-2008 Simultaneous analysis of fat-soluble vitamins

20 Vitamin Losses During Food Storage and Processing Structure of the fat-soluble vitamins vitamin A 16-June-2008 Simultaneous analysis of fat-soluble vitamins

21 Vitamin Losses During Food Storage and Processing Structure of the fat-soluble vitamins vitamin E 16-June-2008 Simultaneous analysis of fat-soluble vitamins

22 Vitamin Losses During Food Storage and Processing Structure of the fat-soluble vitamins vitamin D3 16-June-2008 Simultaneous analysis of fat-soluble vitamins

23 Vitamin Losses During Food Storage and Processing Structure of the fat-soluble vitamins vitamin K1 16-June-2008 Simultaneous analysis of fat-soluble vitamins

24 Vitamin Losses During Food Storage and Processing The vitamins A, E, D3 and K1 are hydrophobic. High affinity by the selected stationary phase (C18 group) Elution of Fat- soluble vitamins 1. Usage of high concentrations of methanol and acetonitrile 2. Use of micelar medium 16-June-2008 Simultaneous analysis of fat-soluble vitamins

25 Vitamin Losses During Food Storage and Processing The anionic SDS surfactant almost did not present absorption in the UV region and was selected as mobile and stationary phase modifier. SDS : sodium dodecyl sulphate 16-June-2008 Micelar medium : Simultaneous analysis of fat-soluble vitamins

26 Vitamin Losses During Food Storage and Processing SDS in concentrations higher than the critical micelar concentration (CMC, 0.24% (w/v)) as mobile phase : Effect of the SDS in the separation of fat-soluble vitamins. 16-June-2008 Simultaneous analysis of fat-soluble vitamins

27 Vitamin Losses During Food Storage and Processing SDS and ethanol in the mobile phase : Effect of the ethanol in the chromatographic separation of fat-soluble vitamins. 16-June-2008 Simultaneous analysis of fat-soluble vitamins

28 Vitamin Losses During Food Storage and Processing Effect of the butyl alcohol in the chromatographic separation of fat-soluble vitamins. SDS and n-butyl alcohol in the mobile phase : 16-June-2008 Simultaneous analysis of fat-soluble vitamins

29 Vitamin Losses During Food Storage and Processing It was possible to elute all the analytes in 70 min. Optimization of the green chromatographic method: to improve the analytical frequency 16-June-2008 SDS and n-butyl alcohol in the mobile phase : Simultaneous analysis of fat-soluble vitamins

30 Vitamin Losses During Food Storage and Processing Experimental conditions pH Temperature Mobile phase flow rate SDS concentration Butyl alcohol concentration 16-June-2008 Constant Factorial Experiment Simultaneous analysis of fat-soluble vitamins

31 Vitamin Losses During Food Storage and Processing Flow rateSDSButyl alcoholExperiment 1.5 mLmin−11.50% (w/v)10.0% (v/v) mLmin−11.50% (w/v)15.0% (v/v) mLmin−115.0% (w/v)10.0% (v/v) mLmin−115.0% (w/v)15.0% (v/v) 4 2.0mLmin−11.50% (w/v)10.0% (v/v) 5 2.0mLmin−11.50% (w/v)15.0% (v/v) 6 2.0mLmin−115.0% (w/v)10.0% (v/v) 7 2.0mLmin−115.0% (w/v)15.0% (v/v) 8 Conditions of the factorial experiment to optimize the determination of the fat-soluble vitamins A, E, D3 and K1 16-June-2008 Simultaneous analysis of fat-soluble vitamins

32 Vitamin Losses During Food Storage and Processing Effect of the mobile flow rate, butyl alcohol and SDS concentrations in the chromatographic separation of fat-soluble vitamins. 16-June-2008 Simultaneous analysis of fat-soluble vitamins

33 Vitamin Losses During Food Storage and Processing 16-June-2008 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. Simultaneous analysis of fat-soluble vitamins

34 Vitamin Losses During Food Storage and Processing 16-June-2008 Determination of fat-soluble vitamins with the proposed green chromatographic method. The results are expressed in mg L −1 ±S.D. Simultaneous analysis of fat-soluble vitamins

35 Vitamin Losses During Food Storage and Processing 16-June-2008 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. Comparison of green and conventional chromatography Simultaneous analysis of fat-soluble vitamins

36 Vitamin Losses During Food Storage and Processing 16-June-2008 Analysis of vitamin C

37 Vitamin Losses During Food Storage and Processing 16-June-2008 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. RDA : recommended daily acceptance Analysis of vitamin C

38 Vitamin Losses During Food Storage and Processing 16-June-2008 Evaluation of the effect of time and temperature on the content of vitamin C of two different brands of pure orange juice by HPLC Analysis of vitamin C

39 Vitamin Losses During Food Storage and Processing 16-June ºC28 ºC18 ºCMonths of storage Orange juice Orange juice 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) Analysis of vitamin C

40 Vitamin Losses During Food Storage and Processing 16-June-2008 Evaluation of the antioxidant activity of the orange juices by FRAP assay FRAP : ferric reducing antioxidant power Analysis of vitamin C Fe 3+ Fe 2+ antioxidant

41 Vitamin Losses During Food Storage and Processing 16-June ºC28 ºC18 ºCMonths of storage Orange juice Orange juice Changes in the antioxidant activity (FRAP mM) in orange juices during 6 months of storage at 18, 28 and 38 ºC Analysis of vitamin C

42 Vitamin Losses During Food Storage and Processing 16-June-2008 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. Analysis of vitamin C

43 Vitamin Losses During Food Storage and Processing 16-June-2008 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.

44 Vitamin Losses During Food Storage and Processing 16-June-2008 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.

45 Vitamin Losses During Food Storage and Processing 16-June-2008 Conclusion : Conclusion Vitamin D is susceptible to the alkaline pH range, light, and heat. Fat content is probably the crucial factor affecting retention during culinary treatment. No losses were found during pasteurization and sterilization of milk or during production of dried or evaporated milk.

46 Vitamin Losses During Food Storage and Processing 16-June-2008 Conclusion : Conclusion 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. Vitamin E is unstable in the presence of oxygen, light, and even some unsaturated fats.

47 Vitamin Losses During Food Storage and Processing 16-June-2008 Conclusion : Conclusion Vitamin K is destroyed by sunlight and decomposed by alkalis. More vitamin K was retained when microwave heating was used.

48 Vitamin Losses During Food Storage and Processing 16-June-2008 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.

49 Vitamin Losses During Food Storage and Processing 16-June-2008 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.

50 Vitamin Losses During Food Storage and Processing 16-June-2008 Conclusion : Conclusion Retention of vitamin B in meats: microwave>frying>parching>steaming>boiling Marinading of fish is the most damaging process.

51 Vitamin Losses During Food Storage and Processing 16-June-2008 References : 1. Journal of Food Composition and Analysis 19 (2006) 252– Talanta 75 (2008) 141– Journal of Food Composition and Analysis 20 (2007) 313– Spectrochimica Acta Part A 65 (2006) 802– Food Chemistry 100 (2007) 1220–1222

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