Sorption characteristics of peeled beans and shells of fermented and dry Trinitario cocoa beans (Theobroma cacao L.)
Resumen
Water sorption data of the peeled bean and shell of Trinitario fermented and dry cocoa beans were determined at 25 °C and adjusted to the isotherm models of Brunauer-Emmet-Teller-(BET) and Guggenheim-Anderson-de Boer-(GAB). The difference in the moisture sorption capacity of the shell and peeled beans was clearly established. The monolayer water contents estimated using the BET and GAB models for the peeled bean was 3.53 and 3.60 g water/100 g dry solids, respectively; while for the shell were 8.42 and 8.50 g water/100 g dry solids. The energy constants (C) obtained applying the BET model for the peeled bean and shell were 154.3 and 163.2, respectively. Those estimated from the GAB model (C´) were 21.63 and 83.56, respectively. A larger C´ value for the shell indicates stronger water binding to the active sites in the monolayer as compared with the peeled beans that could indicate the presence of more active polar sites in the former. The value of the K constant in the GAB model was 0.871 and 0.942 for the peeled bean and shell respectively that could suggest a larger water adsorption by proteinaceous material in the peeled bean.
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Mercier, P., Tusa, A. y Guaíquirian, H.: Adsorción del agua en semilla de café y cacao. Acta Científica Venez, Vol. 33, No. 1 (1982), 398.
Talib, M., Daud, W. and Ibrahim, M.: Moisture desorption isotherms of cocoa beans. Trans. ASAE, Vol. 38, No. 4 (1995) 1153–1155.
Kanmogne, A., Jannot, Y., Lips, B., Nganhou, J.: Sorption isotherms and drying characteristic curve offermented cocoa. Int. J. Sci. Technol., Vol. 2, No. 4 (2012), 19–31.
Akmel, D.C.. Kakou, K. E., Kone, K.Y., Assidjo, N.E. and Kouame, P.: Desorption isotherms and isosteric heats of fermented cocoa beans (Theobroma cocoa). J. Food Res., Vol. 4, No 3 (2015) 138-147.
Gane, R.: The water relations of some dried fruits, vegetables and plant products. J. Sci. Food Agric., Vol. 1, (1950) 42, 1950.
Sandoval, A.J. and Barreiro, J.A.: Water sorption isotherms of non-fermented cocoa beans (Theobroma cacao). J. Food Eng., Vol. 51, No. 2 (2002) 119–123.
Sandoval, A.J., Barreiro, J.A., Tovar, X. and Angueira, M.: Sorption characteristics of fermented cocoa powder (Theobroma cacao). Rev. Tec. la Fac. Ing. Univ. del Zulia, Vol. 25, No. 1 (2002) 49–55, 2002.
Sandoval, A.J., Barreiro, J.A., De Sousa A., Valera D., López, J.V. and Müller, A.J.: Composition and thermogravimetric characterization of components of Venezuelan fermented and dry Trinitario cocoa beans (Theobroma cacao L.): Whole beans, peeled beans and shells. Rev. Técnica la Fac. Ing. Univ. del Zulia, Vol. 42, No. 1 (2019) 39-46.
Sandoval, A.J., Barreiro, J.A., De Sousa A., Valera D., & Müller, A. J.: Determination of the physical properties of fermented and dried beans of Venezuelan Trinitario cocoa (Theobroma cacao L.). Rev. Técnica la Fac. Ing. Univ. del Zulia, Vol. 42, No. 2 (2019) 50-56.
Norma Venezolana Covenin 50:1995. Granos de cacao (2da revisión). Ministerio de Fomento. Caracas, Venezuela, 1995.
AOAC. Official Methods of Analysis of the Association of Official Analytical Chemists. 16th ed. Arlington, VA, 1996.
Anonymus. Operation manual. Decagon CX-1. Decagon Devices, Inc. USA, 1984.
Greenspan, L.: Humidity fixed points of binary saturated aqueous solutions. J. Res. Natl. Bur. Stand. Sect. A Phys. Chem., Vol. 81A, No. 1 (1977) 89-96.
Sandoval, A.J., Guilarte, D., Barreiro, J. A., Lucci E. and Müller, A. J.: Determination of moisture sorption characteristics of oat flour by static and dynamic techniques with and without thymol as an antimicrobial agent. Food Biophys., Vol. 6, No. 3 (2011) 424–432.
Brunauer, S., Emmett, P. and Teller, E.: Adsorption of gases in multimolecular layers. J. Am. Chem. Soc., Vol. 60, No. 2 (1938) 309-319.
Guggenheim, E. Applications of Statistical Mechanics. Oxford: Clarendon Press. UK., 1966.
Anderson, R.: Modifications of the BET equation. J. Am. Chem. Soc., Vol. 68, No. 4 (1946) 689–691, 1946.
De Boer, v.H.J.: The Dynamic Character of Adsorption. 2nd. Oxford: Clarendon Press. UK, 1953.
Thommes, M., Kaneko, K., Neimark, A., Olivier, J., Rodriguez-Reinoso, F., Rouquerol, J. and Sing, K.: Physisorption of gases, with special reference to the evaluation of surface area and pore size distribution (IUPAC Technical Report). Pure Appl. Chem., Vol. 87, No. 9–10 (2015) 1051-1069.
Timmermann, E.O.: Multilayer sorption parameters: BET or GAB values?. Colloids Surfaces A Physicochem. Eng. Asp., Vol. 220, No. 1–3 (2003) 235-260.
Blahovec, J. and Yanniotis, S.: Generalized equation for sorption phenomena. Food and Bioprocess Technology. Food Bioprocess Technol., Vol. 1, No. 1 (2008) 82-90.
Quirijns, E., van Boxtel, A., van Loon, W. and van Strate, G.: Sorption isotherms, GAB parameters and isosteric heat of sorption. J. Sci. Food Agric., Vol. 85, No. 11 (2005) 1805-1814.
Lagunes Gálvez, S., Loiseau, G., Paredes, J.L., Barel, M. and Guiraud, J.P.: Study on the microflora and biochemistry of cocoa fermentation in the Dominican Republic. Int. J. Food Microbiol., Vol. 114, No. 1 (2007) 124-130.
Afoakwa, E.O., Kongor, J.E., Takrama, J. and Budu, A.S.: Changes in nib acidification and biochemical composition during fermentation of pulp pre-conditioned cocoa (Theobroma cacao) beans. Int. Food Res. J., Vol. 20, No. 4 (2013) 1843-1853.
Chirife, J., Timmermann, E.O., Iglesias, H.A., Boquet, R.: Some features of the parameter k of the GAB equation as applied to sorption isotherms of selected food materials. J. Food Eng., Vol. 15, No. 1 (1992) 75-82.
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