Vitamin C Amount Estimation By DCPIP Vitamin C (ascorbic acid) is a very important vitamin to the body. Vitamin C promotes healthy teeth and gums, helps absorption of iron, aids in maintenance of normal connective tissue, promotes wound healing, and helps boost the immune system. With vitamin C being such a useful substance to our bodies, finding good sources of vitamin C is important. Many people today rely on vitamin supplement tablets. But fruit juices, vitamin-supplemented drinks, or vitamin supplemented foods may contain just as much vitamin C as a supplement tablet. Which one is better though, commercially sold drinks or fresh fruit juices? This was the research question: Are commercially sold and popularly consumed juices (in Japan) a good substitute fro fresh fruits in terms of dietary vitamin C? What this experiment sought to find out was exactly what kind of drink was better in terms of dietary vitamin C. The juices were titrated into a set amount of DCPIP and measuring how many millilitres it took for the DCPIP to turn from blue to clear.
The hypothesis was that fresh fruit juices should contain more vitamin C since they had not been heat treated and probably had spent less time on a shelf or being transported than commercially sod drinks. This is important since vitamin C is heat labile. This means that vitamin C is susceptible to change and unstable or that the vitamin C can break down easily if exposed to high temperatures or is kept for a long time on a shelf. The experiment and results showed that vitamin C is more abundant in fresh fruit juices. This was true for all the juices tested except for lemon. Therefore, it is safe to say that fresh fruit juices tend to contain more vitamin C than commercially bought juices.
Introduction The body needs a good balance of foods, which must contain carbohydrates, proteins, and fats along with mineral salts, water, fibre, and vitamins. All of these are required in different amounts according to different people. However, there are recommended daily allowances. For example, the recommended daily allowance for vitamin C is 60mg. Vitamins are easily absorbed into the bloodstream from the gut. A diet lacking in any particular vitamin will lead to a deficiency disease.
Such diseases are rickets that is caused by lack of vitamin D, and night blindness that is caused by lack of vitamin A. However, these can be remedied by using vitamin supplements if the dietary intake is inadequate. The aim of the experiment was to see the difference of vitamin C content between fresh fruit juices and commercially sold and popularly consumed juices (in Japan) a good substitute for fresh fruits in terms of dietary vitamin C? This research question was established because in the modern day and age people are too busy, especially in winter, to stock up on fresh fruit and many people rely on commercially sold drinks as a source of vitamins. However, vitamin C, in particular, is known to be labile and therefore likely to be absent from a cooked food diet. In temperate climates, such as Japan or Europe, people ear fresh fruits in summer, but eat tinned, preserved, or cooked foods in the winter. The latter being more susceptible to heat, possibly breaking down the amount of vitamin C in them.
This experiment tested for the vitamin C content in fresh fruit juices and commercially sold drinks. This experiment was conducted mostly on citrus fruits because vitamin C is said to be abundant in citrus fruits. The experiment was also performed on non-citrus fruits. The experiment was performed on these two types of fruit drinks because vitamin C contributes to maintaining a healthy body, especially during the winter, when citrus fruits are not in season. AS a result, the amount of vitamin C found in each type of juice would be essential in knowing what drinks to choose during the winter to provide the most or the optimum amount of vitamin C.
Using this information, the following hypothesis was formed. Since vitamin C is labile (meaning susceptible to change and unstable), the commercially sold juices, which have most likely been heat treated and stored in various conditions for various periods of time, should have lower vitamin C content than fresh fruit juices. The commercially sold juices would have most likely been exposed to the conditions leading to the deterioration in the content of vitamin C. In this experiment the independent variables were the juices that were being tested for their vitamin C content. The volume of each required to make a standard volume of DCPIP (dichlorophenolindophenol) change from blue to clear was measured.1 This was the dependent variable. These juices were first filtered and then titrated using a burette.
The fixed variable of the experiment was the amount of DCPIP in each beaker and the room temperature. Both of these remained constant throughout the experiment. The importance of the room temperature being constant and not too high is because otherwise the vitamin C content of any and all the juices may have been altered, since vitamin C is heat labile. Moreover, if the temperature varied, the measured results might have varied also. The DCPIP was carefully made to the concentration of 0.1%. In each case 2 millilitres of DCPIP was taken.
The amount, 2 millilitres of DCPIP, was chosen because it was not too much or too little an amount for the reactions to be seen clearly, without taking too much time. Vitamin C was first discovered because of its absence, during the age of exploration. Sailors on long sea voyages suffered very often from bleeding gums, loosened teeth, and aching joints. These were the symptoms of the disease now called scurvy. It is called scurvy because of “the presence of scurfs (or scales) on the skin”.
It was James Lind that showed that scurvy could be cured and prevented by eating “greens, fresh vegetables, and ripe fruits”. However, it was the Polish biochemist, Casimir Funk, which named the missing group vitamines. He named this because he believed that they contained an amine group. Vitamines means “life amines”. It is from the word that we get the word, vitamin.
When vitamin C was finally isolated in 1925, it was given the name ascorbic acid because ascorbic means “no scurvy”.2 Vitamin C has many functions in the body. One of the most important functions is as an antioxidant. This means that it helps prevent oxidation of water-soluble molecules that could otherwise create radicals, which may generate cellular injury, disease, and damage skin cells. It can also be said that it helps neuralise or counteract damage to cells caused by free radicals, which can cause the aging of skin and damage to different cells around the body. Indeed, ascorbic acid (vitamin C) is commonly added to processed food as an antioxidant.
3 In some roles, vitamin C may act as a coenzyme, helping a particular enzyme to do its work, especially where metallic ions play a role. Where there are two oxidation states of metals such as Fe2+ (Iron II) and Fe3+ (Iron III), in the presence of vitamin C the reduced form (Fe2+) prevails. For iron-deficiency anemia, vitamin C helps the absorption of iron (especially the nonheme or vegetable-source iron) from the gastrointestinal tract.4 Specifically, ascorbic acid works as a coenzyme to convert proline and lysine to hydoxyproline and hydroxylysine, both important to the collagen structure. 5 Vitamin C also helps in the stimulation of production of collagen. Collagen is the basis of connective tissue.
It is found in ligaments, skin, cartilage, vertebral discs, capillary walls, bones, and teeth. As a result, vitamin C helps heal wound in the ligaments, blood vessels, skin, and cartilage. It also helps prevent hernias as it protects the inside part of the disc in the vertebral discs where hernias may occur. Vitamin C is also used in skin treatments because it softens the skin and prevents or delays the aging of skin.6 It also helps form serotonin which is an important brain chemical, it stimulates adrenal function, it aids in cholesterol metabolism, helps wounds heal, and helps maintain healthy blood vessels.7 In diabetes, vitamin C is commonly used to improve the utilisation of blood sugar and thereby reduce it, but there is no clear evidence that regular vitamin C usage alone can prevent diabetes.8 There are some preliminary reports that ascorbic acid may help prevent cataract formation (probably through its antioxidant effect) and may be helpful in the prevention and treatment of glaucoma, as well as certain cases of male infertility caused from the clumping together of sperm, which decreases sperm function. Ascorbic acid is also said to act as a detoxifier and may reduce the side effects of drugs such as cortisone, aspirin, and insulin; it may also reduce the toxicity of the heavy metals lead, mercury, and arsenic, either by controlling Oxidation State or by facilitating excretion. There are other proposed functions for vitamin C, but they remain controversial.
For example, it is said that it aids in the production of interferon, which stimulates the immune system, that it is an antihistamine and therefore prevents or lessens the affects of allergies, and it may help prevent certain forms of cancer. In short, vitamin C helps prevent scurvy, promotes healthy teeth and gums, helps absorption of iron, aids in maintenance of normal connective tissue, promotes wound healing, and helps boost the immune system. However, vitamin C is also a natural laxative and may help with constipation problems. In fact, the main side effect of too much vitamin C intake is diarrhea. However, this will not happen if you go over the recommended daily allowance (RDA). For this side effect to occur there would have to be a very high consumption of vitamin C, very fast because it is a water soluble molecule.9 Vitamin C is an important substance in the body.
This is why it is vital that we take in the right amount of vitamin C by eating or drinking the substances that supply us with it. Materials Fresh grapefruit Fresh lemon Fresh orange Fresh pomegranate Fresh apple Fresh mikan (tangerine) Bottle of C100 Vitamin Lemon drink Can of Nichirei Acerola drink Bottle of Sawayaka apple juice Carton of Zakuro (pomegranate) Water drink Carton of grapefruit juice Carton of Dole orange juice Tin of Sanyo mikan Carton of Ringo No Oishii Mizu (Delicious Apple Water) Knife Cutting board Blender Lemon squeezer Filter Distilled water Burette DCPIP (0.1%) solution Funnel White marble tile Paper napkins 14 beakers 6M hydrochloric acid Electronic scales Spatula Pipette Procedures An amount of 0.5g of DCPIP (dichlorophenolindophenol) powder was measured on an electronic scale. Next, 500ml of distilled water were then mixed together to form 500ml of 0.1% DCPIP solution, which was stored in a dark bottle. The solution was a dark blue colour. DCPIP is used for the testing of vitamin C.
When tested for vitamin C, a colour change will take place either from blue to clear, or from blue to pink to clear. Once the full colour change is observed, the amount of solution taken to change it can be recorded. The burette was cleaned thoroughly using hydrochloric acid. The acid was poured in gently so as not to spill while the burette was slowly rotated over a sink. Once this was finished, water was run down the sink so the acid would be diluted and be less harmful to the pipe system. Distilled water was then poured down the burette to make sure the acid was fully rinsed out. The grapefruit had the juice extracted from it using a regular lemon squeezer. The squeezer was then cleaned using distilled water.
The juice was hen filtered using a tea strainer and then a filter paper. The juice was collected in a beaker. This procedure was repeated with an orange, lemon, and a mikan (tangerine). The pomegranate was cut in half and the juice was extracted by squeezing each half using the hand. This juice was also filtered in the same fashion as all the juices. The apple was diced and put into a blender where it was blended until it looked like a puree. This was then filtered and placed into a beaker like the previous juices.
All the juices, including the commercially sold ju8ices, were filtered to prevent blockage of the burette. Next, 16 beakers were each filled with 2ml of 0.1% DCPIP solution. The burette was filled with the fresh grapefruit juice just past the zero line using a funnel to pour it into the burette so the juice would go directly into the burette. The grapefruit juice was then drained until it came exactly to the zero line. Looking at eye level to see if the bottom part of the curvature was exactly at zero checked this.
The grapefruit juice was slowly dripped into the beaker of DCPIP until a clear observation in the colour change was observed. The beaker was swirled gently to ensure mixing. It was properly observed, as a white tile had been placed under the beaker of DCPIP. This made the colour change more clearly visible. The amount of juice taken for a full colour change to take place in the beaker containing DCPIP was recorded.
The burette was then cleaned by pouring distilled water through it twice. The lemon juice was then poured into the burette and the mount of lemon juice taken to observe a clear colour change in the beaker containing DCPIP was recorded. The burette was cleaned once again and the process was repeated with each fresh fruit juice and commercially sold drink. Data Chart showing The Amount of Fruit Juice Needed in mls to Turn DCPIP From Blue To Clear Types of Juices Amount of commercially sold juices in ml needed to turn 2mls of DCPIP clear Amount of fresh juices in mls needed to turn 2 mls of DCPIP clear Grapefruit 50+ ml 2.2 ml Lemon 0.13 ml 2.0 ml Orange 2.9 ml 2.3 ml Pomegranate 50+ ml 11.3 ml Apple 1.4 ml 23.1 ml Mikan (tangerine) 6.5 ml 2.9 ml The above chart shows how many mls of each juice, …