Effects of Storage Periods and Temperature on Mold Prevalence and Aflatoxin Contamination in Nuts
DOI:
https://doi.org/10.3923/pjn.2018.219.227Keywords:
Aflatoxin, mold, nuts, storage temperature, yeastAbstract
Background and Objective: Nuts are highly exposed to fungi contamination in the field during transport or storage and this can result in the production of mycotoxins. The aim of this study was to determine the prevalence and level of aflatoxins (AFB1, AFB2, AFG1 and AFG2), the mold and yeast counts in pistachios, cashews, walnuts, almonds and hazelnuts and the effect of different storage conditions (temperature and storage period) on aflatoxin formation and mold and yeast counts. Materials and Methods: One hundred and twenty-five samples of dehulled raw nuts (pistachio, cashew, walnut, almond and hazelnut) were purchased randomly from retail shops in the Kingdom of Saudi Arabia. The samples were first analyzed to obtain an estimation of the aflatoxin levels, mold and yeast counts prior to storage. The nut samples were then stored for 3 and 6 months at three temperatures: Room temperature (25°C), 45°C and under refrigeration (4°C). At the end of the storage periods, the samples were again analyzed for aflatoxin content (AFB1, AFB2, AFG1 and AFG2) and mold and yeast counts. Results: All of the nuts in the study were found to have safe aflatoxin levels before storage according to the European Union, Iranian and Australian/New Zealand food standard codes (<15 μg kg–1). The aflatoxin levels rose above safe limits in all of the experimental nuts stored for 3 or 6 months at room temperature (25°C) and 45°C. However, storing the experimental nuts under refrigeration (4°C) allowed the pistachio, cashew and walnut aflatoxin levels to remain within the safe limit for up to 6 months. Both the almond and hazelnut aflatoxin levels exceeded the standards by 3 months of storage at 4°C and could not be considered safe. Conclusion: Storing nuts at a low temperature (refrigeration) reduces aflatoxin levels and mold and yeast counts for 3-6 months.
References
Bayman, P., J.L. Baker and N.E. Mahoney, 2002. Aspergillus on tree nuts: Incidence and associations. Mycopathologia, 155: 161-169.
Klich, M.A., S. Tang and D.W. Denning, 2009. Aflatoxin and ochratoxin production by Aspergillus species under ex vivo conditions. Mycopathologia, 168: 185-191.
Magan, N. and M. Olsen, 2004. Mycotoxins in Food: Detection and Control. Woodhead Publishing Ltd., Cambridge, UK., ISBN-13: 9781855737334, Pages: 471.
Saleemullah, A. Iqbal, I.A. Khalil and H. Shah, 2006. Aflatoxin contents of stored and artificially inoculated cereals and nuts. Food Chem., 98: 699-703.
Strosnider, H., E. Azziz-Baumgartner, M. Banziger, R.V. Bhat and R. Breiman et al., 2006. Workgroup report: Public health strategies for reducing aflatoxin exposure in developing countries. Environ. Health Perspect., 114: 1898-1903.
Bankole, S.A., B.M. Ogunsanwo and D.A. Eseigbe, 2005. Aflatoxins in Nigerian dry-roasted groundnuts. Food Chem., 89: 503-506.
Njobeh, P.B., M.F. Dutton, S.H. Koch, A. Chuturgoon, S. Stoev and K. Seifert, 2009. Contamination with storage fungi of human food from Cameroon. Int. J. Food Microbiol., 135: 193-198.
Kaaya, A.N. and W. Kyamuhangire, 2006. The effect of storage time and agroecological zone on mould incidence and aflatoxin contamination of maize from traders in Uganda. Int. J. Food Microbiol., 110: 217-223.
Iqbal, S.Z., I.A. Bhatti, M.R. Asi, H.N. Bhatti and M.A. Sheikh, 2011. Aflatoxin contamination in chilies from Punjab Pakistan with reference to climate change. Int. J. Agric. Biol., 13: 261-265.
Markuszewski, B. and J. Kopytowski, 2015. Effects of storage conditions on the quality of unripe hazelnuts in the husk. J. Hortic. Res., 23: 59-67.
European Commission, 2006. Commission regulation (EC) No. 1881/2006 of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs. Official J. Eur. Union, L364: 5-24.
European Commission, 2001. Commission regulation (EC) No. 466/2001 of 8 March 2001 setting maximum levels for certain contaminants in foodstuffs. Official J. Eur. Communities, L77: 1-13.
Leong, Y.H., N. Ismail, A.A. Latif and R. Ahmad, 2010. Aflatoxin occurrence in nuts and commercial nutty products in Malaysia. Food Control, 21: 334-338.
Codex Alimentarius Commission, 2005. Code of practice for the prevention and reduction of aflatoxin contamination in tree nuts. CAC/RCP 59-2005, Joint FAO/WHO Food Standards Program, Rome, Italy.
Adibian, M., 2016. Aflatoxins in Pistachio, detection and prevention. J. Novel Applied Sci., 5: 27-33.
ICMSF., 1980. Microbial Ecology of Foods, Volume 2: Food Commodities. Academic Press, New York, USA., ISBN: 978-0-12-363522-8, Pages: 687.
Anonymous, 2002. RIDASCREEN® aflatoxin total: Enzyme immunoassay for the quantitative analysis of aflatoxins. Art. No. R4701, R-Biopharm AG, Darmstadt, Germany.
Anonymous, 2004. RIDASCREEN® aflatoxin B1 30/15: Enzyme immunoassay for the quantitative analysis at aflatoxin B1. Art. No. R1211, R-Biopharm AG, Darmstadt, Germany.
Anonymous, 2005. RIDA® aflatoxin column: Immunoaffinity column for sample clean up prior to analysis of aflatoxin. Art. No. R5001/R5002, R-Biopharm AG, Darmstadt, Germany.
Senyuva, H.Z. and J. Gilbert, 2005. Immunoaffinity column cleanup with liquid chromatography using post-column bromination for determination of aflatoxins in hazelnut paste: Interlaboratory study. J. AOAC Int., 88: 526-535.
Nakail, V.K. L. de Oliveira Rocha, E. Goncalez, H. Fonseca, E.M.M. Ortega and B. Corre, 2008. Distribution of fungi and aflatoxins in a stored peanut variety. Food Chem., 106: 285-290.
Snedecor, G.W. and W.G. Cochran, 1980. Statistical Methods. 7th Edn., Iowa State University Press, Iowa, USA., ISBN-10: 0813815606, Pages: 507.
Williams, J.H., T.D. Phillips, P.E. Jolly, J.K. Stiles, C.M. Jolly and D. Aggarwal, 2004. Human aflatoxicosis in developing countries: A review of toxicology, exposure, potential health consequences and interventions. Am. J. Clin. Nutr., 80: 1106-1122.
Aycicek, H., A. Aksoy and S. Saygi, 2005. Determination of aflatoxin levels in some dairy and food products which consumed in Ankara, Turkey. Food Control, 16: 263-266.
Ghirardello, D., G. Zeppa, L. Rolle, V. Gerbi and C. Contessa et al., 2014. Effect of different storage conditions on hazelnut quality. Acta Hortic., 1052: 315-318.
Pacheco, A.M. and V.M. Scussel, 2006. [Chestnut from Brazil: From Tropical Forest to Consumer]. Ediograf, Florianópolis, Brazil Pages: 173, (In Portuguese).
Rosso, L. and T.P. Robinson, 2011. A cardinal model to describe the effect of water activity on the growth of moulds. Int. J. Food Microbiol., 63: 265-273.
Liu, Y., C.C.H. Chang, G.M. Marsh and F. Wu, 2012. Population attributable risk of aflatoxin-related liver cancer: Systematic review and meta-analysis. Eur. J. Cancer, 48: 2125-2136.
Kew, M.C., 2013. Aflatoxins as a cause of hepatocellular carcinoma. J. Gastrointestin. Liver Dis., 22: 305-310.
Lee, L.E., D. Metz, M. Giovanni and C.M. Bruhn, 2011. Consumer knowledge and handling of tree nuts: Food safety implications. Food Protect. Trends, 31: 18-27.
Ozay, G., F. Seyhan, C. Pembeci, S. Saklar and A. Yilmaz, 2008. Factors influencing fungal and aflatoxin levels in Turkish hazelnuts (Corylus avellana L.) during growth, harvest, drying and storage: A 3-year study. Food Addit. Contam. Part A: Chem. Anal. Control Exposure Risk Assess., 25: 209-218.
Gurses, M., 2006. Mycoflora and aflatoxin content of hazelnuts, walnuts, peanuts, almonds and roasted chickpeas (LEBLEBI) sold in Turkey. Int. J. Food Propert., 9: 395-399.
Paramawati, R., P. Widodo, U. Budiharti and Handaka, 2006. The role of postharvest machineries and packaging in minimizing aflatoxin contamination in peanut. Indones. J. Agric. Sci., 7: 15-19.
Waliyar, F., P.L. Kumar, A. Traore, B.R. Ntare, B. Diarra and O. Kodio, 2008. Pre- and Post-harvest Management of Aflatoxin Contamination in Peanuts. In: Mycotoxins: Detection Methods, Management, Public Health and Agricultural Trade, Leslie, J.F., R. Bandyopadhyay and A. Visconti (Eds.). CABI Publishing, Wallingford, UK., ISBN: 9781845930820, pp: 209-218.
Danyluk, M.D., L.J. Harris and D.W. Schaffner, 2006. Monte Carlo simulations assessing the risk of salmonellosis from consumption of almonds. J. Food Protect., 69: 1594-1599.
Rahmianna, A.A., A. Taufiq and E. Yusnawan, 2007. Effect of harvest timing and postharvest storage conditions on aflatoxin contamination in groundnuts harvested from the Wonogiri regency in Indonesia. SAT ejournal, 5: 1-3.
Kimatu, J.N., R. McConchie, X. Xie and S.N. Nguluu, 2012. The significant role of post-harvest management in farm management, aflatoxin mitigation and food security in Sub-Saharan Africa. Greener J. Agric. Sci., 2: 279-288.
Senesi, E., A. Rizzolo, C. Colombo and A. Testoni, 1996. Influence of pre-processing storage conditions on peeled almond quality. Ital. J. Food Sci., 2: 115-125.
Abdulkadar, A.H.W., A. Al-Ali and J. Al-Jedah, 2000. Aflatoxin contamination in edible nuts imported in Qatar. Food Control, 11: 157-160.
Cheraghali, A.M., D. Yazdanpanah, N. Doraki, G. Abouhossain and M. Hassibi et al., 2007. Incidence of aflatoxins in Iran pistachio nuts. Food Chem. Toxicol., 45: 812-816.
Juan, C., A. Zinedine, J.C. Molto, L. Idrissi and J. Manes, 2008. Aflatoxins levels in dried fruits and nuts from Rabat-sale area, Morocco. Food Control, 19: 849-853.
Luttfullah, G. and A. Hussain, 2011. Studies on contamination level of aflatoxins in some dried fruits and nuts of Pakistan. Food Control, 22: 426-429.
Downloads
Published
Issue
Section
License
Copyright (c) 2018 The Author(s)
This work is licensed under a Creative Commons Attribution 4.0 International License.
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.
