INFLUENCE OF HEAT TREATMENT AND MODIFIED ATMOSPHERES PACKAGING ON THE CHEMICAL COMPOSITION OF DATE DEGLET NOUR DURING STORAGE IN COLD
Mots-clés :
Date, Heat treatment, Cold, Modified Atmospheres Packaging, StorageRésumé
A compared study of the simple and combined action ofprocessing and storage has been carried on the date variety Deglet Nour. The samples were heat treated and/or packed in polyethylene film for modifiedatmospheres then stored in cold (10°C) and ambiant temperature (22°C) for 05 months. Results showed that the content in water is similar to the content of water in the half-soft date varieties. Either packed or unpacked refrigerated shares preserve their moisture, while shares stored at room temperature have dried. In control samples, a progressive diminution of the pH values has been observed during the storage. On the other hand, cold and heat treatment stabilizes the pH and the acidity. The content in total sugars decreases strongly during
the storage, particularly at ambiant temperature. The cold slows considerablythis trend and a greater stability is recorded in heat treated - packed shares. The content in reducing sugars is more stable in shares heat treated- chilled or heat treated -packed comparatively to the controls that present fluctuations. These variations are confirmed by the evolution of the saccharose rate inversion. The positive effect of the heat treatment appears clearly when it is associated with the cold and packaging. The phenolic compounds decrease with storage particularly for heat treated samples, while the weakest contents are noted in packed shares. In conclusion, the combined heat treatment - cold - modified atmospheres seems to insure the best behavior of the date that preserves perfectly its initial characteristics of fresh fruit and an excellent market quality.
Références
-Anonyme., ″Normes CEE – ONU DF 08 concernant les dattes entières, Juin (2001)
- Anonyme., ″Séminaire Maghrébien sur le Palmier Dattier″, Biskra, (1992)
-Djerbi M., ″Le bayoud en Algérie, problème et solutions″, Reg. Project for Palm and Dates Research Center in the Near East and North Africa, (1982), IraqFAO, 45 p.
-Doumandji-Mitiche B., ″Les parasites de la datte dans les oasis Algériennes et particulièrement les cas d’Ectomyeloïs ceratoniaeZeller″, Actes du Séminaire Maghrébin sur la Phoéniciculture. El-Oued 18-21 Décembre (1989)
-Rygg G.L., ″Date developpment handling and packing in the United States″, U.S. Developpment of Agriculture, (1975), Handbook n°482, 56 p.
-Benchaabane A., Meftah F. et Saadi A.,. ″Les composés pariétaux de la datte au cours de la maturation″, In: Options Méditerranéennes n°28, Le palmier dattier dans l’agriculture d’oasis des pays méditerranéens, (1996a), pp. 109-110
-Benchaabane A., Meftah F. et Saadi A., ″Caractérisation des substances pectiques et évaluation des autres composés pariétaux au cours de la maturité des dattes en Algérie″, In:Options Méditerranéennes n°28, Le palmier dattier dans l’agriculture d’oasis des pays méditerranéens, (1996b), pp. 109-110
-Reynes M., Lebrun M., et Shaw P., "Identification of volatils components and use of multivariate analysis to distinguish date varieties″, J. Food Quality, Vol. 19, (1996), pp. 505-514
-Rawi Al., Markakis N. P. and Bauer D.H., "Amino acid composition of Iraqui dates″, J. Food Sci.Agric. Vol. 18, (1967), London.
-Mohammed S., Shabana H.R., and Mawlod K.A., ″Evaluation and identification of Iraqui date cultivars: Fruits characteristics of fifty cutivars″, Date Palm J., Vol. 21, N°1 (1983), pp. 27-55
-Nour A.A.M. and. Magboul B.I., "Amino acid colmposition of Sudanese dates cultivars″, Date Palm J., Vol. 4, N° 1 (1985), pp. 51-54
-Salem S.A. and Hegazi S.M., "Chemical composition of some the Egyptian dry dates″, J. of Food. Agric., Vol. 22, (1971), pp. 632-633
-Sawaya W.N., Miski A.M., Khalil J.K., Khatchadourian H.A. and Mashadi A.S., "Physical and chemical characterisation of the major date varieties grown in Saudi Arabia″, Date Palm J., Vol. 2, N°1 (1983), pp. 1-25
-Reynes M., Bouabidi H., Piombo G. and Risterucci A.M., "Caractérisation des principales variétés de dattes cultivées dans une région du Djérid Tunisie″, Fruits, Vol. 49, N°4, (1994), pp. 289-298
-Munier P., "La datte″, In:Le Palmier dattier. Paris. Maisonneuve et Larose, (1973), pp. 141-150
-Hussain A.A., "Date palms and dates with their pests in Iraq″, Mosul University Press,Mosul, Iraq. 130 p.
-Hassan I.M. and El-Sheemy M.G., "Freeze-thaw biochemical changes in three Egyptian date varieties″, Ann. of Agric. Sci., Fac. Ain Shams Univ., Cairo, Egypt. Vol. 34, N°1, (1989), pp. 205-222
-Nixon R.W. and Carpenter J.B., "Growing dates in the United states″, U.S. Departement of Agriculture, Agricultural Information Bulletin. N°207, (1978), 85 p.
-Matter A.A., "Cultivation and production of date palms″, Basrah Univ., Basrah,Iraq. (1991), 420 p.
-Kamal H.M., "Effect of cold storage temperatures on storability and quality of date palm fruits″, Bull. Fac. Agric. Univ. Cairo, N°46, (1995), pp. 265-276
-Anonyme., "Protocole de Montréal relatif aux substances qui appauvrissent la couche d’ozone, (1995)
-Al-Taweel A.A., Ahmed M.S., Naher F.H., Kelewi S.A. and Nasser M.J., "Effect of pupal exposure to various temperatures on certain biological parameters of Ephestia cautella″, Iraqi Agric. J. n°2, (1997), pp. 98-107
-Reynes M. et Tabuna H., "Traitement des dattes par micro-ondes″, In:Options Méditerranéennes n°28, Le palmier dattier dans l’agriculture d’oasis des pays méditerranéens, (1996), pp. 112-113
-Dubois M., Gilles K., Hamilton J.K., Rebers P.A. and Smith F., "Colorimetric method for determination of sugars and releted substances″, Anal. Chem. Vol. 28, (1956), pp: 350-356
-Dahia J., and Passat F., ″Production de sirop de dattes″, Projet régional de recherche sur les palmiers dattiers et les dattes dans le proche orient et l’Afrique du Nord, FAO-Iraq, (1979), 28 p.
-Brenes M., Garcia P., Duran M. and Garrido A., "Concentration of phenolic compounds changes in storage brines of ripe olives″, J Food Sci.; 58, (1992), pp. 347-350
-Horwitz W., "Official Methods of Analysis of the Association of Official Analytical Chemists. 1985. Washington , AOAC (1985)
-Snedecor G. and Cochran W.G., "Methodes Statistiques″, Paris, ACTA, (1984), 649 p.
-Hamdi H., "Absorption de la vapeur d’eau par les dattes tunisiennes″, Fruits, Vol.51, N°3, (1996), pp. 179-184
-Dowson V.H.W. and Aten A., ″Composition et maturation. Récolte et conditionnement des dattes″, Collection FAO. Rome, Cahier N°72, (1963), pp. 1-397
-Khatchadourian W.N., "Processing date varieties into
pickles″, Int. J. Food Sci.Tech. Vol. 2, (1987), pp. 243-247
-Cook J.A., Furr J.R., "Sugar in the fruit of soft semidry and commercial date varieties″, Date Growers Inst. Rept., n°29, (1952), pp. 3-4
-Cook J.A., Furr J.R., "Kinds and relative amounts of sugars and their relation to texture of some American grown date varieties″, Proc. Amer. Soc. Sci., n°61, (1953), pp. 722-727
-Al-Ogaïdi H.K. and Mutlak H.H., "The phenolic compounds of four dates cultivars during maturity stages″, Date palm J. Vol. 3, N°2, (1986), pp. 191-203
-Nezam El Din V., "Tanin and pectin contents of Zahdi date and its products″, Date Palm J. Vol. 3, N°2, (1984), pp. 425-436.
