The Effect of Modified Atmosphere Packaging and Packaging Material on Walnut Kernel Shelf-life

Document Type : Original Paper

Authors

1 Researcher, Kerman Agricultural and Natural Resources Research and Education Center, Agricultural Research, Education, and Extension Organization (AREEO), Kerman, Iran

2 Associate Professor, Food Engineering and Post-Harvest Technology Research Department, Agricultural Engineering Research Institute (ARRI), Agricultural Research, Education, and Extension Organization (AREEO), Karaj, Iran

Abstract

Walnuts with essential and unsaturated fatty acids from omega-3 group, are considered as one of the most important dried fruits with nutritional value. Genotypes 25 and 29 (superior walnut genotypes) were selected to investigate the effect of modified atmosphere packaging on the beneficial compounds of their kernels oil. Walnut kernels were packaged under modified atmospheric conditions into a 90-µm metalized plastic. After the oil cold extraction and purification of walnut kernels, the quantitative and qualitative composition of fatty acids was measured. The percent of fatty acids, aflatoxin content, peroxide index, iodine value, acidity and sensory evaluation of samples were determined in the 0-day and during one year storage. The results showed that the unsaturated fatty acids content are predominant in walnut kernels oil, and the linoleic acid is the dominating fatty acid. The saturated fatty acids content was less than 10%. The aflatoxin content of genotypes 25 and 29 were measured 0 and 5 ppb, respectively. The moisture content and the peroxide value were determined 1.55-4.32% and 0.48-4.65 meqO2/kg, respectively. The highest level of acidity was observed in the 25 genotypes. The peroxide index, titratable acidity, and weight loss increased with the increasing of storage time, while the iodine value decreased. Totally, the packaged genotype 25 in the PA/PE/PA/PE/Aluminum foil films under modified atmospheric containing 5-6% O2, 15% CO2 and 79-80% N2 is recommended due to the high quality of chemical and organoleptic properties and the lack of aflatoxin in the walnuts kernel.

Keywords

Ahmadi, K., Ebadzadeh, H. R., Hatami, F., Hoseinpour, R., Abdeshah, H., Rezaei, M. M., & Fazli Stabragh, M. (2018). Agricultural statistics 2017: Horticultural products, Volume 3. Retrieved from Ministry of Agricultural Jihad, Plannining and Economic Affairs, Information Technology and Communication Center: https://www.maj.ir/Dorsapax/userfiles/Sub65/amarnamehj3-95-site.pdf (in Persian)
Amaral, J. S., Casal, S., Pereira, J. A., Seabra, R. M., & Oliveira, B. P. P. (2003). Determination of Sterol and Fatty Acid Compositions, Oxidative Stability, and Nutritional Value of Six Walnut (Juglans regia L.) Cultivars Grown in Portugal. Journal of Agricultural and Food Chemistry, 51(26), 7698-7702. doi:https://doi.org/10.1021/jf030451d
AOAC. (2005a). Method 923.03. In: Official Methods of Analysis, 21th Edition, AOAC International Publisher, Gaithersburg.
AOAC. (2005b). Official Methods and Recommended practices of the American oil chemists’ society, 4th end.Edited by D. Firestone. In: American oil chemists’ society, Champaign.
Bayat, F., & Mahjub, M. (2017). Walnut properties. Ministry of Agricultural Jihad, Hamedan Agricultural Jihad Organization. Retrieved from http://www.agrilib.ir/book_3465.pdf (in Persian)
Cheraghali, A. M., Yazdanpanah, H., Doraki, N., Abouhossain, G., Hassibi, M., Ali-abadi, S., . . . Zamanian, F. (2007). Incidence of aflatoxins in Iran pistachio nuts. Food and Chemical Toxicology, 45(5), 812-816. doi:https://doi.org/10.1016/j.fct.2006.10.026
Cline, L., & Press, J. (1990). Reduction in almond moth infestation using commercial packaging of foods in combination with the parasitic wasp, Baracon hebetor. J Economic-entomology, 83(3), 1110-1113.
Escobar, B., Estevez, A. M., & Guiñez, M. A. (2000). Storage of cereal bars with mesquite cotyledon (Prosopis chilensis (Mol) Stuntz). Archivos latinoamericanos de nutricion, 50(2), 152-156.
Ghanei Zare, T., Tavakolipour, H., & Elhamirad, A. H. (2012). The effect of packing material and vacuum conditions on the quality properties of dried pistachio during storage time. Journal of Food Science and Processing, 4(1), 65-71.  (in Persian)
Golzari, M., Rahemi, M., Hassani, D., Vahdati, K., & Mohammadi, N. (2013). Protein content, fat and fatty acids of kernel in some persian walnut (Juglans regia L.) cultivars affected by kind of pollen. Food Science and Technology, 10(38), 21-31. (in Persian)
Hamedi, M. (2015). Food Chemistry (2 ed. Vol. 1, ): Tehran University Publishing Center. (in Persian)
Hosseini, Z. (1990). Common methods of food decomposition: Shiraz University Publication. (in Persian)
Iranian National Standardization Organization. (2018). Animal and vegetable fats and oils-Determination of peroxide value-Iodometric (visual) endpoint determination. (ISIRI Standard No. 4179, 2nd Revision). Retrieved from http://standard.isiri.gov.ir/StandardView.aspx?Id=50001 (in Persian)
Maskan, M., & Karatag, S. (1997). Sorption Characteristics of Whole Pistachio Nuts (Pistacia Vera L.). Drying Technology, 15(3-4), 1119-1139. doi:https://doi.org/10.1080/07373939708917282
Mexis, S. F., Riganakos, K. A., & Kontominas, M. G. (2011). Effect of irradiation, active and modified atmosphere packaging, container oxygen barrier and storage conditions on the physicochemical and sensory properties of raw unpeeled almond kernels (Prunus dulcis). Journal of the Science of Food and Agriculture, 91(4), 634-649. doi:https://doi.org/10.1002/jsfa.4225
Ozkan, G., & Koyuncu, M. A. (2005). Physical and chemical composition of some walnut (Juglans regia L) genotypes grown in Turkey. Grasas y Aceites, 56(2), 141-146. doi:https://doi.org/10.3989/gya.2005.v56.i2.122
Piggott, J. R., Simpson, S. J., & Williams, S. A. R. (1998). Sensory analysis. International journal of food science & technology, 33(1), 7-12. doi:https://doi.org/10.1046/j.1365-2621.1998.00154.x
Raee, M., Sedaghat, N., Pourazarang, H., & Hashemi, N. (2007, 4-5 December). Evaluation of the effects of packaging material and modified atmospher conditions on the physicochemical properties of pistachio. Paper presented at the The First Iranian Congress on Processing & Packaging of Pistachio Nuts. https://www.civilica.com/Paper-ICPPPN01-ICPPPN01_029.html (in Persian)
Sattar, A., Mohammad, J., Saleem, A., Jan, M., & Ahmad, A. (1990). Effect of fluorescent light, gamma radiation and packages on oxidative deterioration of dry nuts. Sarhad Journal of Agriculture, 6(3), 235-240.
Stampar, F., Solar, A., Hudina, M., Veberic, R., & Colaric, M. (2006). Traditional walnut liqueur-cocktail of phenolics. Food chemistry, 95(4), 627-631. doi:https://doi.org/10.1016/j.foodchem.2005.01.035
Stiles, M. E., & Ooraikul, B. (1991). Modified Atmosphere Packaging of Foods (B.Tajeddin, Trans. Vol. 2nd). Canada: Alberta University.
Tajeddin, B. (2004). The effect of polymer films on walnut packaging. Pajouhesh & Sazandegi, 62(1-62), 2-8.  (in Persian)
Yaman, A. (2004). Determination of shelf-life of pistachio nut kernel at different packaging materials and workhouse conditions. In: Pistachio Institute, Graziartep, Turkey.
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Volume 8, Issue 4
February 2020
Pages 357-368
  • Receive Date: 12 November 2018
  • Revise Date: 07 September 2019
  • Accept Date: 15 September 2019