Measurement of Iron Content and Detection of Sulfate Ion in Traditional/ Industrial Canned Black Olives in Iran

Author(s): Tayebeh Asadi-Sharifi, Leila Peivasteh-Roudsari, Ebrahim Molaee-Aghaee, Shahrokh Nazmara, Parisa Sadighara*, Amin M. Khaneghah*

Journal Name: Current Nutrition & Food Science

Volume 16 , Issue 7 , 2020

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Graphical Abstract:


Background: Black olive contains considerable concentrations of phenolic compounds, which can result in a higher antioxidant component compared with green olives. Sometimes, as food fraud, the use of unwanted substances has been observed such as iron sulfate or iron particles for blackening olives, eventually causing adverse effects on the tissues of the digestive tract, brain, kidney, and liver in the consumer. The main purpose of this study was to determine flavonoids, iron content and ion sulfate in canned black olives.

Methods: Canned black olive from inland/imported and traditional/industrial samples were collected. The amount of iron, sulfate ion, and flavonoids content were measured by ICP-OES and spectrophotometer, respectively.

Results: Industrial black olives (brand N) from Turkey showed the highest iron content (110.17 mg/kg) and traditional black olives purchased from Rudbar, showed the lowest iron content (6.72 mg/kg). These values were lower than the iron limit in canned black olives (150 mg/kg). The highest and lowest levels of sulfate were also found in the traditional black olive of Rudbar and industrial black olives of Greece, respectively. Sulfate amount was determined between 23.225-82.102 mg/kg. Traditional black olives of Roudbar had the highest flavonoid, and the lowest flavonoid content was shown by the industrial black olive of Turkey. The pH was in the range of 4.4-4.8, indicating that the pH of any of the samples was not higher than the standard maximum level.

Conclusion: According to the results of this study, iron sulfate has not been added intentionally to the collected samples.

Keywords: Black olive, flavonoid, iron, pH, sulfate, phenolic compounds.

Bonatsou S, Benítez A, Rodríguez-Gómez F, Panagou EZ, Arroyo-López FN. Selection of yeasts with multifunctional features for application as starters in natural black table olive processing. Food Microbiol 2015; 46: 66-73.
[] [PMID: 25475268]
Șen M, Yentürk A. Zero discharge of olive waste: green energy application. Olivae 2016; 123: 37-42.
El Adlouni C, Tozlovanu M, Naman F, Faid M, Pfohl-Leszkowicz A. Preliminary data on the presence of mycotoxins (ochratoxin A, citrinin and aflatoxin B1) in black table olives “Greek style” of Moroccan origin. Mol Nutr Food Res 2006; 50(6): 507-12.
[] [PMID: 16688704]
Owen RW, Haubner R, Mier W, et al. Isolation, structure elucidation and antioxidant potential of the major phenolic and flavonoid compounds in brined olive drupes. Food Chem Toxicol 2003; 41(5): 703-17.
[] [PMID: 12659724]
Soler‐Rivas C, Espín JC, Wichers HJ. Oleuropein and related compounds. J Sci Food Agric 2000; 80: 1013-23.
Rice-Evans C, Miller N, Paganga G. Antioxidant properties of phenolic compounds. Trends Plant Sci 1997; 2: 152-9.
Di Giovacchino L. Technological Aspects. In: Aparicio R, Ramon H, Eds. Handbook of Olive Oil: Analysis and Properties. Gaithersburg, Maryland: Aspen Publication 2000; pp. 57-96.
Piga A, Gambella F, Vacca V, et al. Response of three Sardinian olive cultivars to Greek-style processing. Ital J Food Sci 2001; 13: 29-40.
Şahan Y, Basoglu F, Gücer S. ICP-MS analysis of a series of metals (Namely: Mg, Cr, Co, Ni, Fe, Cu, Zn, Sn, Cd, and Pb) in black and green olive samples from Bursa, Turkey. Food Chem 2007; 105: 395-9.
Tassou C, Panagou E, Katsaboxakis K. Microbiological and physicochemical changes of naturally black olives fermented at different temperatures and NaCl levels in the brines. Food Microbiol 2002; 19: 605-15.
Beltran-Heredia J, Torregrosa J, Dominguez JR, et al. Treatment of black-olive wastewaters by ozonation and aerobic biological degradation. Water Res 2000; 34: 3515-22.
Papadakis IE, Sotiropoulos TE, Therios IN. Mobility of iron and manganese within two citrus genotypes after foliar applications of iron sulfate and manganese sulfate. J Plant Nutr 2007; 30: 1385-96.
Vinha AF, Ferreres F, Silva BM, et al. Phenolic profiles of Portuguese olive fruits (Olea europaea L.): influences of cultivar and geographical origin. Food Chem 2005; 89: 561-8.
Altundag H, Tuzen M. Comparison of dry, wet and microwave digestion methods for the multi element determination in some dried fruit samples by ICP-OES. Food Chem Toxicol 2011; 49(11): 2800-7.
[] [PMID: 21843582]
Tian QL, Liao SH, Lu P, et al. Spectroscopic study on the interaction of Al3+ with flavonoids and BSA. Chin J Chem 2006; 24: 1388-90.
Biswas AK, Chatli MK, Sahoo J. Antioxidant potential of curry (Murraya koenigii L.) and mint (Mentha spicata) leaf extracts and their effect on colour and oxidative stability of raw ground pork meat during refrigeration storage. Food Chem 2012; 133(2): 467-72.
[] [PMID: 25683421]
Hansen NC, Hopkins BG, Ellsworth JW, et al. Iron nutrition in field crops. In: Barton LL, Abadia J, Eds. Iron nutrition in plants and rhizospheric microorganisms. Dordrecht: Springer 2006; pp. 23-59.
Lindsay W. Inorganic equilibria are affecting micronutrients in soils. Micronutr Agric 1991; 4: 89-112.
Rombolà AD, Tagliavini M. Iron nutrition of fruit tree crops. In: Barton LL, Abadia J, Eds. Iron nutrition in plants and rhizospheric microorganisms. Dordrecht: Springer 2006; pp. 61-83.
Madejón P, Marañón T, M. Murillo J. Biomonitoring of trace elements in the leaves and fruits of wild olive and holm oak trees. Sci Total Environ 2006; 355(1-3): 187-203.
[] [PMID: 15890386]
Vlahov G. Flavonoids in three olives (Olea europaea) fruit varieties during maturation. J Sci Food Agric 1992; 58: 157-9.
Piga A, Del Caro A, Pinna I, et al. Anthocyanin and color evolution in naturally black table olives during anaerobic processing. Lebensm Wiss Technol 2005; 38: 425-9.

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Article Details

Year: 2020
Published on: 10 September, 2020
Page: [1112 - 1118]
Pages: 7
DOI: 10.2174/1573401316666191224115107
Price: $65

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