Determining Ascorbic Acid Content In Vegetables And Fruits: An Essay.

Experiment Method

Trial	Initial burette reading(A)	Final burette reading (B)	Dye titrated (B-A)ml
1.	4.0	10.1	6.1
2.	12.1	19.5	7.4

i) Concentration of standard ascorbic acid solution used in the experiment = 2 mg/5 ml=0.4mg/ml.

ii) Volume of standard ascorbic acid solution given in the experiment= 5 ml

iii) Volume of dye solution required =6.75ml.

Dye titrated (average) = 6.1+7.4/2 = 13.5ml/2=6.75ml. 2mg/5ml of standard ascorbic acid solution (0.4mg/ml) with volume of 5ml.

Formula to be used:

Milligram of ascorbic acid =Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

Milligram of ascorbic acid of dye solution= 6.75ml x 0.4mg/ml= 2.7mg

Amount of ascorbic acid equivalent to 1ml of dye= 2.7mg---Answer.

Weight of spinach =15 gram of fresh spinach leaves were used.

The total volume used= 20ml,

Aliquot volume used= 10ml.

Trial	Initial burette reading(A)	Final burette reading(B)	Dye titrated(ml)(B-A)
1.	12.5ml	19ml	6.5ml
2.	22ml	27.4ml	5.4ml

Dye titrated average in ml= 5.95ml

1. The amount of ascorbic acid in mg/100g of spinach fresh tissue= mg of ascorbic acid used in titration sample sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of spinach in grams.
2. Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.
3. a) Average amount of ascorbic acid used in the titration in the aliquot= 5.95 ml x 0.4 mg/1ml of dye=2.38mg
4. b) The amount of ascorbic acid content in mg/100g of fresh tissue= 2.38 mg x 20ml x 100/ 10ml x 15 gram.

The amount of ascorbic acid in mg/100g of fresh tissue= 4760/150= 31.73mg of ascorbic acid/100 g tissue—Answer.

Weight of spinach: 10 g,

Total volume used in the experiment: 20 ml,

Aliquot volume used in the experiment: 10 ml.

Trial	Initial burette reading (A)	Final burette reading (B)	Dye titrated (ml) (B-A)
1.	17.4ml	20.1ml	2.7ml
2.	22.1ml	25ml	2.9ml

Dye titrated average in ml=5.6ml/2=2.8ml.

1. Amount of ascorbic acid content in mg/100g of boiled tissue = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of spinach in grams.
2. a. Average amount of ascorbic acid used in titration experiment aliquot= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

Amount of ascorbic acid used in titration experiment sample aliquot= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye. Amount of ascorbic acid used in the titration= 2.8 ml x 0.4mg/1ml of dye=1.12mg

1. The amount of ascorbic acid in mg/ 100g of boiled spinach tissue=

1.12 x 20 x 100/ 10ml x 10g =2240/100=22.4mg

The amount of ascorbic acid in mg/ 100g of boiled spinach tissue= 22.4mg—Answer.

Boiled water,

Weight of spinach leaves: 10 g,

Total volume of aliquot taken: 20 ml,

Aliquot volume taken for experimentation: 10 ml.

Trial	Initial burette reading(A)	Final burette reading(B)	Dye titrated (A-B)
1.	10ml	12ml	2ml
2.	14ml	16ml	2ml

Dye titrated average in ml= 2ml

1. Average of ascorbic acid lost in the water after 100g spinach leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of spinach in grams.
2. Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.
3. Amount of ascorbic acid used in titration experiment sample aliquot= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

1. Average ascorbic acid lost in the water after 100g spinach leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of spinach in grams.
2. Average of ascorbic acid lost in the water after 100g spinach leaves tissue was boiled for 5 minutes = 0.8 x 20 x 100/10x 10 = 1600/100=16mg—Answer.

Weight of spinach leaves: 1000g (1Kg),

Total volume of aliquot taken: 30 ml,

Aliquot volume taken for experimentation: 10 ml.

Trial	Initial burette reading(A)	Final burette reading(B)	Dye titrated (A-B)
1.	10ml	12ml	2ml
2.	14ml	16ml	2ml

Dye titrated average in ml= 2ml

1. Average of ascorbic acid lost in the water after 1000g spinach leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of spinach in grams.
2. Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

1. Average amount of ascorbic acid used in titration experiment sample= 2ml x 0.4mg/ml=0.8mg
2. Average of ascorbic acid lost in the water after 1000g spinach leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of spinach in grams.

Average of ascorbic acid lost in the water after 1000g spinach leaves tissue was boiled for 5 minutes = 0.8 x 30 x 100/10x 1000 = 2400/10000=0.24mg—Answer.

1. Cabbage leaves

Trial	Initial Burette reading	Final Burette reading	Dye titrated (B-A)ml
1.	8.2ml	15.4ml	7.2ml
2.	13.1ml	20.2ml	7.1ml

i) Concentration of standard ascorbic acid solution used in the experiment = 2 mg/5 ml=0.4mg/ml.

ii) Volume of standard ascorbic acid solution given in the experiment= 5 ml

iii) Volume of dye solution required =7.15ml.

Dye titrated (average) = 7.2+7.1/2 = 14.3ml/2=7.15ml. 2mg/5ml of standard ascorbic acid solution (0.4mg/ml) with volume of 5ml.

Milligram of ascorbic acid =Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

Milligram of ascorbic acid of dye solution= 7.15 ml x 0.4mg/ml= 2.86mg

Amount of ascorbic acid equivalent to 1ml of dye= 2.86mg---Answer.

Weight of cabbage =20 gram of fresh cabbage leaves were used. The total volume used= 25ml, Aliquot volume used= 15ml.

Trial	Initial burette reading(A)	Final burette reading(B)	Dye titrated(ml)(B-A)
1.	14.5ml	20.2ml	5.7ml
2.	21.3ml	28.7ml	7.4ml

Dye titrated average in ml= 5.7ml+7.4ml/2= 6.55ml

1. The amount of ascorbic acid in mg/100g of cabbage fresh tissue= mg of ascorbic acid used in titration sample aliquot x total volume of extract in ml x 100/ volume of aliquot in ml x weight of cabbage in grams.
2. Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.
3. Average amount of ascorbic acid used in the titration in the aliquot= 6.55 ml x 0.4 mg/1ml of dye=2.62mg
4. The amount of ascorbic acid content in mg/100g of fresh tissue=2.62 mg x 25ml x 100/ 15ml x 20 gram.

The amount of ascorbic acid in mg/100g of fresh tissue= 6550/300= 21.83mg of ascorbic acid/100 g tissue—Answer. 

Weight of cabbage: 20 g,

 Total volume used in the experiment: 25 ml,

Aliquot volume used in the experiment: 15 ml.

Trial	Initial burette reading (A)	Final burette reading (B)	Dye titrated (ml) (B-A)
1.	15.2ml	19.1ml	3.9ml
2.	20.3ml	24.8ml	4.5ml

Dye titrated average in 3.9ml+4.5ml/2=8.4/2=4.2ml.

1. Amount of ascorbic acid content in mg/100g of boiled tissue = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of cabbage in grams.
2. a. Average amount of ascorbic acid used in titration experiment aliquot= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

Amount of ascorbic acid used in titration experiment sample aliquot= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye. Amount of ascorbic acid used in the titration= 4.2ml x 0.4mg/1ml of dye=1.68mg

1. The amount of ascorbic acid in mg/ 100g of boiled cabbage tissue= 1.68 x 25 x 100/ 15ml x 20g =4200/300=14.0mg

The amount of ascorbic acid in mg/ 100g of boiled cabbage tissue= 14.0mg—Answer.

Boiled water,

Weight of cabbage leaves: 25 g

Total volume of aliquot taken: 25 ml Aliquot volume taken for experimentation: 15 ml.

Trial	Initial burette reading(A)	Final burette reading(B)	Dye titrated (A-B)
1.	11.8ml	13.5ml	1.7ml
2.	12.5ml	17.5ml	5ml

Dye titrated average in ml= 6.7/2ml=3.35ml

1. Average of ascorbic acid lost in the water after 100g cabbage leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of cabbage in grams.
2. Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.
3. Amount of ascorbic acid used in titration experiment sample aliquot= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

Amount of ascorbic acid used in titration experiment sample aliquot = 3.35ml x 0.4mg/ml=1.34mg

1. Average ascorbic acid lost in the water after 100g cabbage leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of cabbage in grams.
2. Average of ascorbic acid lost in the water after 100g cabbage leaves tissue was boiled for 5 minutes = 1.34 x 25 x 100/15x 20 = 3350/300=11.16mg—Answer.

Weight of cabbage leaves: 1000g (1Kg)

Total volume of aliquot taken: 30 ml Aliquot volume taken for experimentation: 10 ml.

Trial	Initial burette reading(A)	Final burette reading(B)	Dye titrated (A-B)
1.	11.4ml	14.2ml	2.8ml
2.	13.5ml	18.4ml	4.9ml

Dye titrated average in ml= 2.8+4.9ml=7.7/2=3.85ml

1. Average of ascorbic acid lost in the water after 1000g cabbage leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of cabbage in grams.
2. Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

Amount of ascorbic acid used in titration experiment sample= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.

3. Average amount of ascorbic acid used in titration experiment sample= 3.85ml x 0.4mg/ml=1.54mg
4. Average of ascorbic acid lost in the water after 1000g cabbage leaves tissue was boiled for 5 minutes = mg of ascorbic acid used in sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of cabbage in grams.

Average of ascorbic acid lost in the water after 1000g cabbage leaves tissue was boiled for 5 minutes = 3.85 x 30 x 100/10x 1000 = 11550/10000=1.155mg—Answer.

Weight of apple: 75g

Total volume used: 350ml

Aliquot volume used: 175ml

Trial	Initial Burette reading(A)	Final burette reading (B)	Dye titrated B-A ml
1.	14 ml	19.5 ml	5.5
2.	19ml	24ml	5

Dye titration volume average in ml: 5.5+/2=10.5/2=5.25ml

1. The amount of ascorbic acid in mg/100g of apple fresh tissue= mg of ascorbic acid used in titration sample sample x total volume of extract in ml x 100/ volume of aliquot in ml x weight of apple in grams.
2. Amount of ascorbic acid used in titration experiment sample aliquot= Amount of titrated dye (ml) x ascorbic acid (mg) /1ml of dye.
3. Average amount of ascorbic acid used in the titration in the aliquot= 5.25 ml x 0.4 mg/1ml of dye=2.10mg ascorbic acid--Answer
4. The amount of ascorbic acid content in mg/100g of fresh apple tissue= 2.10 mg x 350ml x 100/ 175ml x 75 gram.

The amount of ascorbic acid in mg/100g of fresh tissue= 73500/13125= 5.6mg of ascorbic acid/100 g tissue—Answer.

Answer 6: The potential error in the protocol is that there may be more loss of the ascorbic acid content in the fruits apple and cabbage due to the degradation of the ascorbic acid at high temperatures. There is a degradation of ascorbic acid content in different fruits during the time interval of 4 days-7 days when heated at a high temperature (Mussa and El Sharaa, 2014). 

Answer 7: The intake of vitamin C is important during pregnancy because this vitamin has several important functions like supporting the growth of cells, helpful in cellular repair mechanisms, preventing the occurrence of neural tube defects during pregnancy, and helping in the synthesis of DNA inside the cells. Vitamin C is also essential for the synthesis of collagen which provides structural support to the skin layer and is also essential for the synthesis of the neurotransmitter (Edward and Hans, 2010). In children, the intake of vitamins boosts the immune system and strengthens the nervous system. Vitamin C supports the growth and development of children and provides strong flexible support to the skin layers (Child, 2020). 

Answer 8: The major sources of vitamins present in the food diet are as follows citrus fruits, red tomatoes green leafy vegetables available in the market like cabbage, broccoli, cauliflower, and lettuce (Ofoedu et al., 2021).

Answer 9: Various factors affect the content of Vitamin C in the diet like the heating of food at high temperatures during cooking, exposure of food containing vitamin C to light, and radiation. The change in pH affects the content of Vitamin C present in the different food sources (Lee et al., 2017). 

1. Child, T., 2020. Vitamin C for Kids: The 6 Best Benefits - Brauer Health Library. Brauer Natural Medicines.
2. Diengdoh F, D., E R, Dkhar., T, Mukhim. and C L, Nongpiur., 2015. Worldwidejournals.com.
3. Edward, B. and Hans, U., 2010. Regular vitamin C supplementation during pregnancy reduces hospitalization: outcomes of a Ugandan rural cohort study. Pan African Medical Journal, 5(1).
4. Isleroglu, H., Yilmazer, M. and Ertekin, F., 2016. Kinetics of colour, chlorophyll, and ascorbic acid content in spinach baked in different types of oven. Taylor & Francis.
5. Koh, E., Charoenprasert, S. and Mitchell, A., 2012. Effect of Organic and Conventional Cropping Systems on Ascorbic Acid, Vitamin C, Flavonoids, Nitrate, and Oxalate in 27 Varieties of Spinach (Spinacia oleracea L.). Journal of Agricultural and Food Chemistry, 60(12), pp.3144-3150..
6. Lee, S., Choi, Y., Jeong, H., Lee, J. and Sung, J., 2017. Effect of different cooking methods on the content of vitamins and true retention in selected vegetables. Food Science and Biotechnology.
7. Mussa, S. and El Sharaa, I., 2014. Analysis of Vitamin C (ascorbic acid) Contents packed fruit juice by UV-spectrophotometry and Redox Titration Methods. IOSR Journal of Applied Physics, 6(5), pp.46-52.
8. N.C, Igwemmar., S.A, Kolawole. and I.A, Imran., 2013. Effect of Heating on Vitamin C Content of Some Selected Vegetables. Ijstr.org.
9. Ofoedu, C., Iwouno, J., Ofoedu, E., Ogueke, C., Igwe, V., Agunwah, I., Ofoedum, A., Chacha, J., Muobike, O., Agunbiade, A., Njoku, N., Nwakaudu, A., Odimegwu, N., Ndukauba, O., Ogbonna, C., Naibaho, J., Korus, M. and Okpala, C., 2021. Revisiting food-sourced vitamins for consumer diet and health needs: a perspective review, from vitamin classification, metabolic functions, absorption, utilization, to balancing nutritional requirements. PeerJ, 9, p.e11940.
10. Samuel, P. and Godrick, E., 1997. Human Metabolism of Vitamin C and Fruit Juice Analysis.
11. Toledo, M., Ueda, Y., Imahori, Y. and Ayaki, M., 2003. l-ascorbic acid metabolism in spinach (Spinacia oleracea L.) during postharvest storage in light and dark. Postharvest Biology and Technology, 28(1), pp.47-57.
12. Varsha T, R. and Padma P, N., 2017. Comparative Studies on Ascorbic acid content in Various Fruits, Vegetables and Leafy Vegetables.
13. Yadav, S. and Sehgal, S., 1995. Effect of home processing on ascorbic acid and ?-carotene content of spinach (Spinacia oleracia) and amaranth (Amaranthus tricolor) leaves. Plant Foods for Human Nutrition, 47(2), pp.125-131