Document Type: Research paper

Authors

Department of Horticultural Sciences, College of Agriculture, Shahid Chamran University of Ahvaz, Iran

Abstract

The fruit of date palm (Phoenix dactylifera L.) is an important horticultural product in the Middle East and North Africa. Among more than 400 reported date palm cultivars in Iran, around 20 cultivars are more important due to having better eating quality and trading values. In this study, the fruit of nine commercially important date cultivars including ‘Barhee’, ‘Breim’, ‘Deiri’, ‘Fersi’, ‘Gantar’, ‘Khadravi’, ‘Sayer’, ‘Shakar’ and ‘Zahidi’ were evaluated for certain quality and biochemical properties during the last three stages of ripening (i.e., Khalal, Rutab and Tamar). The results showed that the highest levels of total soluble solids (TSS) and titratable acidity were recorded at Tamar stage for all studied cultivars. Maximum TSS was recorded for ‘Deiri’ (77 %) and ‘Zahidi’ (75.3%) which are considered as dry dates. By a similar pattern, the mean amount of soluble proteins, flesh darkening and peroxidase activity (POX) increased to 5587 μg g-1, 0.76 A410 and 5220 Ug-1 tissue, respectively. Fruit at Khalal stage showed an incredible amount of phenolic compounds and antioxidant capacity, but these parameters of nutritional value reduced to their lowest level in almost all studied cultivars at Tamar stage. Flesh darkening as an index of appearance quality increased greatly by turning Rutab into Tamar for almost all cultivars.

Keywords

Al-Farsi, M., C. Alasalvar, A. Morris, M. Baron and F. Shahidi. 2005. Comparison of Antioxidant Activity, Anthocyanins, Carotenoids, and Phenolics of Three Native Fresh and Sun-Dried Date (Phoenix dactylifera L.) Varieties Grown in Oman. J. Agr. Food. Chem. 53:7592–7599.
Al-Shahib, W. and R.J. Marshall. 2003. The Fruit of the date Palm: Its Possible Use as the Best Food for the Future? Int. J. Food Sci. Nutr. 54:247-259.
Amira, E.A., F. Guido, S.E. Behija, I. Manel, Z. Nesrine, F. Ali, H. Mohamed, H.A. Noureddine and A. Lotfi. 2011. Chemical and Aroma Volatile Compositions of Date Palm (Phoenix
dactylifera L.) Fruits at Three Maturation Stages. Food Chem. 127:1744–1754.
Arnon, D.L. 1949. A Copper Enzyme is Isolated Chloroplast Polyphenol Oxidase in Beta vulgaries. Plant Physiol. 24:1-15.
Awad, M.A., A.D. Al-Qurashi and A.S. Mohamed. 2011. Antioxidant Capacity, Antioxidant Compounds and Antioxidant Enzyme Activities in five Date Cultivars During Development and Ripening. Sci. Hort. 129:688–693.
Bacha, M.A., T.A. Nasr and M.A. Shaheen. 1987. Changes in Physical and Chemical Characteristics of the Fruits of Four Date Palm Cultivars. Proc. Saudi Biolog. Soc. 25:285-295.

Baliga, M.S., B.R.V. Baliga, S.M. Kandathil, H.P. Bhat and P.K. Vayalil. 2011. A Review of the Chemistry and Pharmacology of the Date Fruits (Phoenix dactylifera L.). Food Res. Int. 44:1812–1822.
Baloch, M.K., S.A. Saleem, A.K. Baloch and W.A. Baloch. 2006. Impact of Controlled Atmosphere on the Stability of Dhakki Dates. Food Sci. Tech. 39: 671-676.
Barry, G.H. and A.A. Van Wyk. 2006. Low-temperature Cold Shock may induce Rind Color Development of ‘Nules Clementine’ Mandarin (Citrus reticulata Blanco) Fruit. Postharvest Biol. Tech. 40:82–88.
Bates L.S., R.P. Waldren and I.D. Teare. 1973. Rapid Determination of Free Proline for Water-Stress Studies. Plant Soil. 39:205-207.
Benzie, I.F. and J.J. Strain. 1996. The Ferric Reducing Ability of Plasma (FRAP) as a Measure of Antioxidant Power: FRAP Assay. Annu. Rev. Biochem. 239:70-76.
Boudries, H., P. Kefalas and D. Hornero-Mendez. 2007. Carotenoid Composition of Algerian Date Varieties (Phoenix dactylifera) at Different Edible Maturation Stages. Food Chem. 101:1372–1377.
Bradford, M.M. 1976. A Dye Binding Assay for Protein. Anal. Biochem. 72:248-254.
Chao, C.T. and R.R. Krueger. 2007. The Date Palm (Phoenix dactylifera L.): Overview of Biology, Uses and Cultivation. HortScience 42:1077-1082.
Ding, C.K., K. Chachin, Y. Ueda, Y. Imahori and C.Y. Wang. 2001. Metabolism of Phenolic Compounds During Loquat Fruit Development. J. Agr. Food Chem. 49:2883-2888.
El-Sohaimy, S.A. and E.E. Hafez. 2010. Biochemical and Nutritional Characterizations of Date Palm Fruits (Phoenix dactylifera L.). J. App. Sci. Res. 6:1060-1067.
Guy, C., D. Haskell, L. Neven, P. Klein and C. Smelser. 1992. Hydration-State-Responsive Protein Link Cold and Drought Stress in Spinach. Planta 188:265-270.
Hasnaoui, A., M.A. Elhoumaizi, A. Asehraou, M. Sindic, C. Deroanne and A. Hakkou. 2010. Chemical Composition and Microbial Quality of Dates Grown in Figuig Oasis of Morocco. Int. J. Agr. Biol. 12:311–314.
Hasnaoui, A., M.A. Elhoumaizi, A. Hakkou, B. Wathelet and M. Sindic. 2011. Physico-Chemical Characterization, Classification and
Quality Evaluation of Date Palm Fruits of Some Moroccan Cultivars. J. Sci. Res. 3:139-149.
Khali, M. and G. Selselet-Attou. 2007. Effect of Heat Treatment on Polyphenol Oxidase and Peroxidase Activities in Algerian Stored Dates. Afr. J. Biotechnol. 6:790-794.
Khoddami, A., M.A. Wilkes and T.H. Roberts. 2013. Techniques for Analysis of Plant Phenolic Compounds. Molecules 18:2328-2375. Lado, J., M.J. Rodrigo and L. Zacarías. 2014. Analysis of Ethylene Biosynthesis and Perception During Postharvest Cold Storage of Marsh and Star Ruby Grapefruits. Food Sci. Technol. Int. In press.
Lee, J., R.W. Durst and R.E. Wrolstad. 2005. Determination of Total Monomeric Anthocyanin Pigment Content of Fruit Juices, Beverages, Natural Colorants, and Wines by the pH Differential Method: Collaborative Study. J. AOAC Int. 88:1269–1278.
Mondal, K., S.P. Malhotra, V. Jian and R. Singh. 2009. Oxidative Stress and Antioxidant Systems in Guava (Psidium guajava L.) Fruits During Ripening. Physiol. Mol. Biol. Plants 15:327–334.
Michigan State University. 1988. User’s Guide to MSTAT-C a Software Program for the Design, Management, and Analysis of Agronomic Research Experiment. MSU, USA.
Mortazavi, S.M.H., K. Arzani and M. Barzegar. 2010. Analysis of Sugars and Organic Acids Contents of Date Palm (Phoenix dactylifera L.) Barhee During Fruit Development. Acta Hort. 882:793-801.
Mortazavi, S.M.H. 2007. Physicochemical Changes During Fruit Growth and Ripening and Effect of Some Packing Conditions on the Postharvest Quality and Shelf Life of Date Palm Fruit (Phoenix dactylifera L.), cv. Barhee, Ph.D. thesis, Tarbiat Modares Univrsity. 192 p.
Neves, V.A. 2002. Ionically Bound Peroxidase from Peach Fruit. Braz. Arch. Biol. Technol. 45:7–16.
Pandey, V.P., S. Singh, R. Singh and U.N. Dwivedi. 2012. Purification and Characterization of Peroxidase from Papaya (Carica papaya) Fruit. Appl. Biochem. Biotechnol. 167:367–376.
Saleem, A.S., A.K. Baloch, M.K. Baloch, W.A. Baloch and A. Ghaffoor. 2005. Accelerated Ripening of Dhakki Dates by Artificial Means: Ripening by Acetic Acid and Sodium Chloride. J. Food Eng. 70:61–66.

Saradhi, A. and P.P. Saradhi. 1991. Proline Accumulation under Heavy Metal Stress. J. Plant Phys. 138:554-558.
Slinkard, K. and V.L. Singleton. 1977. Total Phenol Analyses: Automation and Comparison with Manual Methods. Amer. J. Enol. Viticult. 28:49-55.
Sriyook, S., Siriatiwat S. and J. Siriphanich. 1994. Durian Fruit Dehiscence-Water Status and Ethylene. HortScience 29:1195-1198.
Stines, A., D.J. Naylor, P.B. Hoj and R. Van heeswijck. 1999. Proline Accumulation in
Developing Grapevine Fruit Occurs Independently of Changes in the Levels of Delta1-Pyrroline-5-Carboxylate Synthetase mRNA or Protein. Plant Physiol. 120:923–931.
Szabados, L. and A. Savoure. 2009. Proline: Multifunctional Amino Acid. Trends Plant Sci. 15:89-97.
Zaid, A. 1999. Date Palm Cultivation. FAO Plant Production and Protection Paper 156, Roma. 292 p.