Vitamin C and nitrates contents in fruit and vegetables from farmers' markets and supermarkets
Keywords:ascorbic acid, nitrate, fruit, vegetable, farmers' market
Fruits and vegetables are the best food sources of vitamin C. However, fruits and vegetables can be also sources of potentially harmful substances to the human body, nitrates being one of these. The aim of this study was to compare vitamin C and nitrates contents in selected fruits and vegetables from supermarkets and local farmers' markets. Samples of plums, strawberries, apples, spinach, red peppers and tomatoes were chosen for analysis. Content of vitamin C and nitrates was analyzed by HPLC/DAD. The hypothesis was that local market fruits and vegetables contain more vitamin C and fewer nitrates than samples bought in supermarkets. Laboratory analyses showed that there were differences in vitamin C in the case of strawberries, tomatoes and red peppers. The highest level of ascorbic acid was in red pepper samples
(141 mg.100g-1). In the case of fruit, the highest content was in strawberries (70 mg.100g-1). As far as nitrates content is concerned, in three cases out of six, the fruit and vegetables we tested from farmers' markets contained lower concentrations of nitrates than those purchased at supermarkets and the hypothesis was accepted in these cases. There was no significant difference between the nitrate content of the local market and supermarket strawberries and red peppers. Tomatoes had significantly higher nitrate content when purchased at farmers' markets than at supermarkets. Leafy vegetables are considered to be the major source of nitrates, and this was confirmed by this study. The highest content of nitrates was in the spinach sample (2969 mg.kg-1). Among all fruit samples, strawberries had the highest nitrates levels (maximum 131 mg.kg-1). The results of this work showed that the content of ascorbic acid and nitrates differs significantly depending on the type of fruit or vegetables.
Andrade, C. A. W., Miguel, A. C. A., Spricigo, P. C., Dias, C. T. S., Jacomino, A. P. 2017. Comparison of quality between organic and conventional strawberries from multiple farms. The Revista Brasileira de Fruticultura, vol. 39, no. 2, p. e-045. https://doi.org/10.1590/0100-2945207045
Bahadoran, Z., Mirmiran, P., Jeddi, S., Azizi, F., Ghasemi, A., Hadaegh, F. 2016. Nitrate and nitrite content of vegetables, fruits, grains, legumes, dairy products, meats and processed meats. Journal of Food Composition and Analysis, vol. 51, p. 93-105. https://doi.org/10.1016/j.jmr.2016.06.006
Barker, A. V. 1975. Organic vesrsus inorganic nutrition and horticultural crop quality. Horticultural Science, vol. 10, p. 50-53.
Bevc, S., Hojs, R., Ekart, R., Završnik, M., Gorenjak, M., Puklavec, L. 2012. Simple cystatin C formula for estimation of glomerular filtration rate in overweight patients with diabetes mellitus type 2 and chronic kidney disease. Experimental Diabetes Research, vol. 2012, p. 1-8. https://doi.org/10.1155/2012/179849
Bohatec, P. 2011. Farmářské trhy: Základní legislativní požadavky z oblasti potravin (Farmers' markets: Basic legislative requirements in the field of food). Available at: https://slideplayer.cz/slide/3130853/. (In Czech)
Bordeleau, G., Myers-Smith, I., Midak, M., Szeremeta, A. 2002. Food quality: A comparison of organic and conventional fruits and vegetables. Available at: https://edepot.wur.nl/115486.
Brůčková, T. 2012. Farmers´markets as a phenomenon of time (Farmářské trhy jako fenomén doby) : bachelor thesis. Univerzita Pardubice, Pardubice, Czech Republic, 55 p. (In Czech)
Bureau, S., Mouhoubi, S., Touloumet, L., Garcia, C., Moreau, F., Bédouet, V., Renard, C. M. G. C. 2015. Are folates, carotenoids and vitamin C affected by cooking? Four domestic procedures are compared on a large diversity of frozen vegetables. LWT-Food Science and Technology, vol. 64, no. 2, p. 735-741. https://doi.org/10.1016/j.lwt.2015.06.016
Cardoso, P. C., Tomazini, A. P. B., Stringheta, P. C., Ribeiro, S. M. R., Pinheiro-Sant´Ana, H. M. 2011. Vitamin C and carotenoids in organic and conventional grown in Brazil. Food Chemistry, vol. 126, no. 2, p. 411-416. https://doi.org/10.1016/j.foodchem.2010.10.109
Colla, G., Kim, H. J., Kyriacou, M. C., Rouphael, Y. 2018. Nitrate in fruits and vegetable. Scientia Horticulturae, vol. 237, p. 221-238. https://doi.org/10.1016/j.scienta.2018.04.016
Combs, G. F. 2017. The vitamins: fundamental aspects in nutrition and health. 5th ed. London, UK : Academic Press, 612 p. ISBN 978-0-12-802965-7.
Duncan, C., Li, H., Leifert, C., Kelly, D., Golden, M. 1999. Bacterial nitrate reductase activity is induced in the oral cavity by dietary nitrate. In Wilson, W. S. et al. Managing Risks of Nitrates to Humans and the Environment. Cambridge, UK : Woodhead Publishing, p. 289-294. ISBN 9781855738089. https://doi.org/10.1533/9781845693206.289
Commission Regulation (EC) No 1881/2006 of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs. OJ L 364, 20.12.2006, p. 1-20.
Du, S., Zhang, Y., Lin, X. 2007. Accumulation of nitrate in vegetables and its possible implications to human health. Agricultural Sciences in China, vol. 6, no. 10, p. 1246-1255. https://doi.org/10.1016/S1671-2927(07)60169-2
EFSA. 2008. Opinion of the Scientific Panel on Contaminants in the Food chain on a request from the European Commission to perform a scientific risk assessment on nitrate in vegetables. The EFSA Journal, vol 689, p. 1-79. Available at: https://efsa.onlinelibrary.wiley.com/doi/epdf/10.2903/j.efsa.2008.689.
EFSA. 2017. Dietary reference values for nutrients. Summary report. EFSA Supporting Publications, p. e15121. Available at: https://efsa.onlinelibrary.wiley.com/doi/pdf/10.2903/sp.efsa.2017.e15121.
Esch, J. R., Friend, J. R., Kariuki, J. K. 2010. Determination of the vitamin C content of conventionally and organically grown fruits by cyclic voltammetry. International Journal of Electrochemical Science, vol. 5, p. 1464-1474.
George, B., Kaur, C., Khurdiya, D. S., Kapoor, H. C. 2004. Antioxidants in tomato (Lycopersicon esculentum) as a function of genotype. Food Chemistry, vol. 84, no. 1, p. 45-51. https://doi.org/10.1016/S0308-8146(03)00165-1
Jeney‐Nagymate, E., Fodor, P. 2008. The stability of vitamin C in different beverages. British Food Journal, vol. 110, no. 3, p. 296-309. https://doi.org/10.1108/00070700810858709
Kopec, K. 2010. Zelenina ve výživě člověka (Vegetable in human nutrition) Prague, Czech Republic : Grada Publishing, 168 p. ISBN 978-80-247-6604-1. (In Czech)
Kukla, D. 2012. Pět důvodů proč nakupovat lokální potraviny (Five reasons to buy local food). Available at: https://www.vitalia.cz/clanky/pet-duvodu-proc-nakupovat-lokalni-potraviny/.
Lee, S. K., Kader, A. A. 2000. Preharvest and postharvest factors influencing vitamin C content of horticultural crops. Postharvest Biology and Technology, vol. 20, no. 3, p. 207-220. https://doi.org/10.1016/S0925-5214(00)00133-2
Lewin, S. 1976. Vitamin C: its molecular biology and medical potential. London, UK : Academic Press, 231 p. ISBN- 0 12 446 3509.
Lundberg, J. O., Carlström, M., Larsen, F. J., Weitzberg, E. 2011. Roles of dietary inorganic nitrate in cardiovascular health and disease. Cardiovascular Research, vol. 89, no. 3, p. 525-532. https://doi.org/10.1093/cvr/cvq325
Mařáková, V. 2008. Možnosti využití plodů méně známých keřovin (Fruit utilizing occasion of less knowing bushes) : bachelor thesis. Brno, Czech Republic : Vysoké učení technické v Brně. 36 p. (In Czech)
Matějková, J., Petříková, K. 2010. A scorbic acid contents in selected vegetables in relation to variety, growing site, year and storage. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, vol. 58, no. 1, p. 95-100. https://doi.org/10.11118/actaun201058010095
Maynard, D. N., Barker, A. V., Minnotti, P. L., Peck, N. H. 1976. Nitrate Accumulation in Vegetables. Advances in Agronomy, vol 28, p. 71-118. https://doi.org/10.1016/S0065-2113(08)60553-2
McCance, R. A., Widdowson, E. M. 2014. McCance and Widdowson's The composition of foods. 7th summary ed. Cambridge, UK : Royal Society of Chemistry, 630 p. ISBN-978-0-85404-428-3.
Muramoto, J. 1999. Comparison of nitrate content in leafy vegetables from organic and conventional farms in California. Available at: https://www.researchgate.net/profile/Joji_Muramoto/publication/267241324_Comparison_of_Nitrate_Content_in_Leafy_Vegetables_from_Organic_and_Conventional_Farms_in_California_Revised_Version/links/546e1dac0cf2bc99c21521d9.pdf.
Nováková, L., Solich, P., Solichová, D. 2008. HPLC methods for simultaneous determination of ascorbic and dehydroascorbic acids. TrAC Trends in Analytical Chemistry, vol. 27, no. 10, p. 942-958. https://doi.org/10.1016/j.trac.2008.08.006
Oyetade, O. A., Oyeleke, G. O., Adeoke, B. M., Akintude, A. O. 2012. Stability studies on ascorbic acid (vitamin C) from different sources. IOSR Journal of Applied Chemistry, vol. 2, no. 4, p. 20-24. https://doi.org/10.9790/5736-0242024
Prasad, S., Chetty, A. A. 2008. Nitrate-N determination in leafy vegetables: Study of the effects of cooking and freezing. Food Chemistry, vol. 106, no. 2, p. 772-780. https://doi.org/10.1016/j.foodchem.2007.06.005
Prugar, J. 2008. Kvalita rostlinných produktů na prahu 3. tisíciletí (Quality of plant products on the threshold oof the 3rd millennium). Prague, Czech Republic : Výzkumný ústav pivovarský a sladařský ve spolupráci s komisí jakosti rostlinných produktů ČAZV, 327 p. ISBN 978-80-86576-28-2. (In Czech)
Rekha, C., Poornima, G., Manasa, M., Abhipsa, V., Devi, J. P., Kumar, H. T. V., Kekuda, T. R. P. 2012. Ascorbic acid, total phenol content and antioxidant activity of fresh juices of four ripe and unripe citrus fruits. Chemical Science Transactions, vol. 1, no. 2, p. 303-310. https://doi.org/10.7598/cst2012.182
Santamaria, P. 2006. Nitrate in vegetables: toxicity, content, intake and EC regulation. Journal of the Science of Food and Agriculture, vol. 86, no. 1, p. 10-17. https://doi.org/10.1002/jsfa.2351
Saxholt, E., Christensen, A. T., Møller, A., Hartkopp, H. B., Hess Ygil, K., Hels, O. H. 2008. Danish Food Composition Databank. Available at: http://www.foodcomp.dk/.
Sedláček, J. 2015. Kodex farmářských trhů (Farmers' Market Code). Available at: http://www.aftcr.cz/kodex-farmarskych-trhu. (In Czech)
Shehata, S. A. 2010. Nitrate detoxification of drinking water by ascorbic acid in growing rabbits. World Rabbit Science, vol. 13, no. 2, p. 93-106. https://doi.org/10.4995/wrs.2005.526
Silva, L. F. L., De Souza, D. C., Resende, L. V., Nassur, R. C. M. R., Samartini, C. Q., Goncalves, W. M. 2018. Nutritional evaluation of non-conventional vegetabels in Brazil. Annals of the Brazilian Academy of Sciences, vol. 90, no. 2, p. 1775-1787. https://doi.org/10.1590/0001-3765201820170509
Sobko, T., Marcus, C., Govoni, M., Kamiya, S. 2010. Dietary nitrate in Japanese traditional foods lowers diastolic blood pressure in healthy volunteers. Nitric Oxide, vol. 22, no. 2, p. 136-140. https://doi.org/10.1016/j.niox.2009.10.007
Soni, V. K., Khan, F., Sonim, A. B., Chandra, C. 2017. Determination of ascorbic acid infFruitjJuices by reducing behaviour of oxalohydroxamic acid. International Journal of Engineering Technology Science and Research, vol. 4, no. 9, p. 1336-1342.
Sorensen, J. M., Johansen, A. S., Poulsen, N. 1994. Influence of growth conditions on the value of crisphead lettuce. I. Marketable and nutritional quality by nitrogen supply, cultivar and plant age. Plant Foods for Human Nutrition, vol. 46, no. 1, p. 1-11.
Stopes, C., Woodward, L., Forde, G., Vogtmann, H. 1989. Effect of composted FYM and a compound fertiliser on yield and nitrate accumulation on three summer lettuce cultivars grown in an organic system. Agriculture, Ecosystems and Environment, vol. 27, p. 555-559. https://doi.org/10.1016/0167-8809(89)90116-3
Temme, E. H. M., Vandevijvere, S., Vinkx, C., Huybrechts, I., Goeyens, L., Van Oyen, H. 2011. Average daily nitrate and nitrite intake in the Belgian population older than 15 years. Food Additives & Contaminants Part A: Chemistry, Analysis, Control, Exposure & Risk Assessment, vol. 28, no. 9, p. 1193-1204. https://doi.org/10.1080/19440049.2011.584072
Walker, R. 1990. Nitrates, nitrites and N ‐nitrosocompounds: A review of the occurrence in food and diet and the toxicological implications. Food Additives and Contaminants, vol. 7, no. 6, p. 717-768. https://doi.org/10.1080/02652039009373938
Webb, A., Patel, N., Loukogeorgakis, S., Okorie, M., Aboud, Z., Misra, S., Rashid, R., Miall, P., Deanfield, J., Benjamin, N., MacAllister, R., Hobbs, A. J., Ahluwalia, A. 2008. Acute Blood Pressure Lowering, Vasoprotective, and Antiplatelet Properties of Dietary Nitrate via Bioconversion to Nitrite. Hypertension, vol. 51, no. 3, p. 784-790. https://doi.org/10.1161/HYPERTENSIONAHA.107.103523
WHO. 2003. WHO Fruit and vegetable promotion initiative. A meeting report. Available at: https://apps.who.int/iris/bitstream/handle/10665/68395/WHO_NMH_NPH_NNP_0308.pdf?sequence=1&isAllowed=y.
WHO. 2004. Vitamin and mineral requirements in human nutrition. 2nd ed. Geneva, Switzerland : World Health Organization, Food and Agricultural Organization of the United Nations. 341 p. ISBN-92 4 154612 3.
Wunderlich, S. M., Feldman, C., Kane, S., Hazhin, T. 2009. Nutritional quality of organic, conventional, and seasonally grown broccoli using vitamin C as a marker. International Journal of Food Sciences and Nutrition, vol. 59, no. 1, p. 34-45. https://doi.org/10.1080/09637480701453637
How to Cite
LicenseAuthors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).