Precooling Parameters Of 'roxo De Valinhos' Figs (ficus Carica L.) Packed In A Carton Box

Introduction. Figs of the variety 'Roxo de Valinhos' are currently cooled in a cold room at a temperature between (1 and 3)°C, and it is unknown how long it takes to cool the fruits to that temperature. The work was based on the need to determine the parameters of forced-air precooling of figs packed in a carton box used for exportation and commercialization in São Paulo State, Brazil. Materials and methods. The fruits were harvested at the harvest rami stage (3/4 of maturity) and at size "type 8", corresponding to eight fruits per box, making up a total of 24 fruits per package. Forty-eight packages were utilized, 24 on each side to form a Californian tunnel. The airflow was 2.8 L·s-1 per kg of product, with an average velocity of the air of 2.0 m·s-1. The initial interior temperature of the fruits was 20°C and the final temperature was 1°C. The evolution of the fig interior temperature was registered. Results. The cooling curve was drawn and the exponential analytical model to predict the precooling parameters was made based on the experimental data. The cooling curve of fig showed a typical behavior; the average fruit temperature during precooling presented a rapid fall at the beginning of the cooling, and slowly declined when it was close to the final temperature. Conclusion. The cooling time was 110 min, the cooling coefficient was 0.0344 min-1, the Biot number was 1.3 and the convective heat transference coefficient was 23.8°C·W -1·m-2. © 2006 Cirad/EDP Sciences All rights reserved.616401406Turk, R., Effects of harvest time and pre-cooling on fruit quality and cold storage of Ficus carica L. cv. 'Bursa syahjiu (1989) Acta Hortic, 258, pp. 279-285Dincer, I., Thermal cooling data for figs exposed to air cooling (1995) Int. Commun. Heat Mass Transf, 22, pp. 559-566Dincer, I., Transient heat transfer analysis in air cooling of individual spherical products (1995) J. Food Eng, 26, pp. 453-467Leal P.A.M., Cortez L.A.B., Métodos de préresfriamento de frutas e hortalizas, in: II Curso Atual. Tecnol. Resfr. Frut. Hortal., Fac. Eng. Agríc. (UNICAMP), Campinas-SP, Brazil, 1998, pp. 81-91Talbot, M.T., Chau, K.V., (1991) Precooling strawberries, p. 942. , Inst. Food Agric. Sci, Univ. Fla, Circ, USAFraser H.W., Forced-air cooling of fresh Ontario fruits and vegetables, Minist. Agric. Food., Toronto, Ontario, 1991Chau K.V., Mathematical modelling of postharvest processes, Grupo Tecnol. Pós-Colheita, Univ. Estadual Campinas, Fac. Eng. Agríc., Campinas-SP, Brazil, 2001Dussán-Sarria S., Honório S.L., Condutividade e difusividade térmica do figo (Ficus carica L.) 'Roxo de Valinhos', Rev. Bras. de Eng. Agríc. 24 (2004) 185-194Mohsenin, N.N., (1980) Thermal properties of foods and agricultural materials, Gordon Breach Sci, pp. 198-224. , Publ, New York, USAGoyette, B., Vigneault, C., Panneton, B., Raghavan, G.S.V., Method to evaluate temperature at the surface of horticultural crops (1997) Can. Agric. Eng, 38, pp. 292-295(1998) Methods of precooling fruits, vegetables and ornamentals, Am, pp. 14.1-14.10. , Soc. Heat. Refrig. Air-Cond. Eng, ASHRAE, Refrigeration handbook Inc, Atlanta, Georgia, USA, AnonTeruel M.B., Estudo teórico - experimental do resfriamento de laranja e banana com ar forçado, Univ. Estadual Campinas, Fac. Eng. Mec.,Thesis, Campinas, Brazil, 2000, 300 pDincer, I., Cooling parameters and film conductances of spherical products cooled in an airflow (1995) Appl. Energy, 50, pp. 269-280Dincer, I., Simplified solution for temperature distributions of spherical and cylindrical products during rapid air cooling (1995) Energy Convers. Manag, 36, pp. 1175-1184Baird, C.D., Gaffney, J.J., Talbot, M.T., Design criteria for efficient and cost effective forced-air cooling systems for fruits and vegetables (1988) ASHRAE Trans, 94, pp. 1434-145