Yield and Physical Characteristics of Neem (Azadirachta indica) and Castor (Ricinus communis) Oils
This work aimed to evaluate the yield and viscosity of neem (Azadirachta indica) and castor (Ricinus communis) oils. Neem fruits were collected at the ‘Núcleo de Pesquisa do Semi-Árido’, municipality of Patos, Paraíba state, and castor plants were collected along the Espinharas River margins, municipalities of Patos and Igaracy, Paraíba state, Brazil. The fruits were beneficiated at the Forest Products Technology Laboratory in Patos. Seed samples were used for determination of moisture content and yield of oils from the studied species. The oils were extracted with absolute ethyl alcohol and employed in the preparation of neem and castor oil solutions. The density and viscosity of solutions were determined. Castor oil presented lower moisture content and yield compared with neem oil. The density and viscosity of neem oil were lower than those of castor oil. A larger amount of castor oil provided an increase in the density and viscosity of the prepared solutions.