2020-22 Unit 6 LA A Project Proposal name
Investigating Project Proposal: Vitamin C content in fruit juices
Question: What fruit juice contains the most vitamin C?
Background research and project proposal:
My investigative project will be the vitamin C content in raw lemon, grapefruit and orange
juices. It can be helpful to know what fruits contain vitamin C and can be useful as vitamin C
helps to protect and keep cells healthy, maintaining healthy skin, healthy blood vessels,
bones and cartilage (NHS, 2019).
Part A.P2
Vitamin C is found in a variety of foods, particularly fruits and vegetables (NHS, 2019).
Supplements containing vitamin C are also available (National Institutes of Health, 2021) . Vitamin C is
also known by the names L-ascorbic acid, ascorbic acid, and L-ascorbate (Medicalnewstoday.com,
2021). It is important to consume vitamin C as it is a water-soluble vitamin that the body does
not store (Atli Arnarson, 2017). People must take vitamin C-containing foods on a daily basis in
order to maintain optimal levels (Medicalnewstoday.com, 2021).
Vitamin C is required by the body for a variety of tasks (NHS, 2019). Here are a few examples:
● It aids in the production of collagen, L-carnitine, and certain neurotransmitters in the
body (Medicalnewstoday.com, 2021).
● As an antioxidant, it aids in the removal of undesirable molecules from the body
known as reactive oxidative species (ROS) (Medicalnewstoday.com, 2021).
● It aids iron absorption in the body (Medicalnewstoday.com, 2021).
● It helps the immune system (Medicalnewstoday.com, 2021).
● It improves healing of wounds (Medicalnewstoday.com, 2021).
Vitamin C deficiency (Scurvy) causes bruising, gum and tooth issues, dry hair and skin, and
anaemia (Medicalnewstoday.com, 2021). Symptoms and, in some cases, blood tests are used to
make the diagnosis (Dr Mary Harding, 2018). Increased intake of fresh fruits and vegetables, or
taking vitamin C tablets directly, typically corrects the deficit (MSD Manual Consumer Version, n.d.).
The recommended daily dose of vitamin C for grownups is 65 to 90 mg, with a daily
maximum of 2,000 mg (Zeratsky, K., 2018). Although excessive dietary vitamin C is unlikely to be
dangerous, megadoses of vitamin C supplements may result in: diarrhoea, nausea,
vomiting, heartburn, abdominal cramps, headache, and insomnia (Zeratsky, K., 2018). So it is
important to know the amount of vitamin C that people consume daily and know what juices
contain the most vitamin C (Zeratsky, K., 2018).
What is blue DCPIP?
Blue DCPIP is a redox indicator dye that turns colourless when reduced and takes electrons
(www.chemeurope.com, n.d.). As vitamin C is an antioxidant (Chakraborthy et al., 2014), it causes DCPIP to
decolorize when it comes into contact with it (EBI Web Team, 2015). This may be used to
determine the amount of Vitamin C in fruit juice (Saps.org.uk, 2019). DCPIP can be used to figure
out how much vitamin C is in a chosen food (Saps.org.uk, 2019). DCPIP turns blue when
dissolved in water, red when exposed to acid, and colourless when exposed to ascorbic acid
(vitamin C) (Sserc.org.uk, 2020).
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, 2020-22 Unit 6 LA A Project Proposal name
Analysis of a literature search (Literature review and source reliability):
I have read a lot of publications and journals while working on this report. The article
"Comparison of vitamin C content in citrus fruits by titration and high performance liquid
chromatography (HPLC) techniques," I discovered, was a trustworthy article. It was
composed in April of 2017. The International Food Research Journal published this journal.
The International Food Research Journal (IFRJ) publishes papers in English six times per
year and covers the following topics: Food Science and Technology Nutrition and Dietetics
Agriculture, multidisciplinary Chemistry, and multidisciplinary. Because this journal was
produced in 2017, the data is current and can be reliable. This article is about a study that
compared vitamin C content in citrus fruits by titration, which is what my investigation is
about, thus it is appropriate to include the data in this report. This strengthens the article's
reliability by demonstrating that it was based on genuine research conducted by a university.
The article is trustworthy since the authors used a variety of sources, citations, and a
bibliography containing all of the information sources used.
(Livestrong.com, 2021) - This article appears to be trustworthy because the author, Melodie
Anne, has a master's degree in food science and human nutrition and is an NRA-certified
instructor. It also includes information from the USDA, the National Institutes of Health, and
Oregon State University. This article helped me to create my hypothesis of orange being the
fruit with the most vitamin C content and grapefruit the fruit with the least amount of vitamin
C. I got this hypothesis from the data they shared from their research and studies.
(Sserc.org.uk, 2020) - Is likely to be a reliable source as it is a student guide that was
published by SQA (Scottish Qualifications Authority) and the SSERC (Scottish Schools
Science Equipment Research Centre). This website also helped me to create a hypothesis
as it agrees with (Science & Plants for Schools, 2011) that DCPIP turns colourless when
exposed to ascorbic acid (vitamin C) and that the more vitamin C in the juice, the faster it
turns colourless.
(Zeratsky, K., 2018) - It is a reliable source of information as the website Mayo Clinic is a
clinical practise, teaching, and research organisation dedicated to delivering skilled,
whole-person treatment to anybody in need of healing. And the author Katherine Zeratsky, is
a registered dietitian with the Minnesota Department of Health and the American Dietetic
Association. She was also a licensed nutritionist and a health risk assessor.
(MSD Manual Consumer Version, n.d.) - It is also likely to be a reliable article as the website
contains lots of information in all medical fields that are written by lots of top medical experts
like the author of this article, Larry E. Johnson, who has an MD, and PhD in medical
sciences and specialises in preventive medicine, family medicine and geriatrics.
(Medicalnewstoday.com, 2021) - It is a reliable source of information as it is an organisation
that gives free health information using “peer reviewed studies, medical experts, and
reputable sources”. This article was written by Joseph Nordqvist and then medically
reviewed by Alan Carter, who is a certified immunising pharmacist with a PharmD.
(Snabbiology.co.uk, 2017) - This is a reliable website for this investigation as it was made to
help A-level Biology and chemistry students with their practicals and was written quite
recently (2017) and also reviewed a couple of years after the publication.
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