Mechanical Characteristics Of Endocarp And Kernel Of Cashew Nut 'ccp 76' Prior And Post Thermal Treatment [características Físicas E Mecânicas Do Endocarpo E Da Amêndoa Da Castanha De Caju 'ccp 76' Antes E Após Tratamento Térmico]

Viscoelastic characteristics of raw cashew nut shell hinder its decortication by compression. In order to facilitate the shell opening and to liberate the kernel, nuts were subjected to hydration and thermal treatment in cashew nut shell liquid (CSL) at 210 °C. With the objective of developing more appropriate shelling mechanisms the cashew nut 'CCP 76' was characterized by its main dimensions, mass and volume, as well as mechanical behavior of the endocarp and kernel, prior and after thermal treatments. The treatments consisted in submitting the nuts to several combinations of hydration and thermal treatment times. The response surface methodology was applied to identify the best treatment. Specially built devices were used for manual opening of the cashew nut, shear of the endocarp and penetration of the kernel. Changes were observed in the dimensions, length, width, and thickness as well as in mass and volume values prior and after treatments. Results of endocarp shear and kernel stiffness tests pointed out differences between raw and treated nuts. Changes in dimensions, mass, and volume pointed out to performing sizing after thermal treatments if dimensions are relevant in shelling. The response surface methodology indicated that the treatment comprising 79 h hydration and 165 s of residence in CSL at 210 °C was the closest to the optimum region.283565578ARAUJO, M. C. Caracterização mecânica da castanha de caju (Anacardium ocidentale L.)para fins de beneficiamento e desenvolvimento de decorticador de cilindros rotativos. 108 f. Dissertação (Mestrado em Engenharia Agrícola) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola, Campinas, 2005BALASUBRAMANIAN, D., Physical properties of raw cashew nut (2001) Journal of Agricultural Research, 78 (3), pp. 291-297BARROS NETO, B., SCARMINIO, I.S., BRUNS, R.E., (2002) Comofazer experimentos-pesquisa e desenvolvimento na ciencia e na indústria, , Campinas: Editora da Unicamp, 401 pBORGES, A., PELEG, M., Effect of water activity on the mechanical properties of selected legumes and nuts (1997) Journal Science Food Agricultural, 75, pp. 463-471. , New York, vCHIAVERINI, V., (1986) Tecnologia mecânica, , 2. ed. São Paulo: Makron Books, 266 pMELO, M.L.P., MAIA, G.A., SILVA, A.P.V., OLIVEIRA, G.S.F., FIGUEIREDO, R.W., Caracterização físico-química da amêndoa da castanha de caju (Anacardium occidentale L.) crua e tostada. (1998) Ciência e Tecnologia de Alimentos, 18 (2), pp. 184-187. , Campinas, vMOHSENIN, N.N., (1970) Physical properties of plant and animal materials: Structure, physycal characteristics and mechanical properties, , New York: Gordon and Breach Science Publishers, 891 pOLOSO, A.O., CLARKE, B., Some aspects of strength properties of cashew nuts (1993) Journal of Agricultural Engineering Research, Silsoe, 55 (1), pp. 27-43PERSSON, S. Mechanics of cutting plant material. St. Joseph: ASAE Technical Editor, 1987. 288