A prensagem mecânica é o método mais empregado para extração do óleo de diversos tipos de oleaginosas, constituindo-se em uma operação simples que não exige mão de obra qualificada e facilmente adaptável a diversos tipos de grãos. Entretanto, as prensas contínuas com pequena capacidade, tem um grande potencial de utilização nas pequenas comunidades rurais, apresentam baixa eficiência de extração, deixando uma quantidade significativa de óleo na torta. A operação de retirada das cascas dos frutos de crambe, antes da prensagem, constitui-se em um fator importante que pode otimizar a extração mecânica do óleo de crambe, reduzindo o teor de óleo que se perde pelo processamento do grão com casca. O objetivo deste trabalho foi avaliar o rendimento de óleo de crambe extraído mecanicamente, contendo diferentes percentagens de retirada de casca. Foram realizados os testes de rendimento de extração do óleo pelo método mecânico de prensagem a frio, a partir do crambe submetido aos seguintes tratamentos de descasque: grãos sem casca, grãos com 10% de casca, grãos com 20% de casca e grãos com casca (controle). Para avaliar o efeito do descasque foi utilizado um delineamento experimental inteiramente casualizado, com quatro tratamentos e quatro repetições. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Os resultados obtidos neste trabalho permitiram observar o efeito positivo e significativo do descasque dos grãos sobre a extração do óleo de crambe, atingindo o máximo rendimento com a ausência de casca.PALAVRAS-CHAVE: crambe, descasque, rendimento de extração, prensagem mecânica, eficiência de extração. DEHULLING PROCESS OF CRAMBE [Crambe Hyspanica subesp. Abyssinica (Hochst. ex R.  E. Fr.) PRINA] AIMING TO OIL EXTRACTIONABSTRACT: The mechanical screw pressing (expeller) is the method most commonly used for extracting oil from various types of oilseeds, constituting of a simple operation that requires no skilled labor and is easily adaptable to various types of grain. However, continuous presses with small capacity have great potential of use in small rural communities, and have low extraction efficiency, leaving a significant amount of oil in the crambe cake. To remove the hull from crambe fruits before pressing is an important factor that can optimize the mechanical extraction of crambe oil, reducing oil waste. The purpose of this work was to evaluate the yield of mechanically extracted oil from crambe fruits containing different percentages of hull. The oil extraction yield tests were performed by the cold pressing method, submitting the crambe to the following hulling treatments: totally dehulled, partially dehulled with 10% hull, partially dehulled with 20% hull, and whole grains (control). To evaluate the dehulling effect, a completely randomized experimental design was used, with four treatments and four replications.  The results were submitted to analysis of variance and the averages were compared by the Tukey’s test at 5% probability.  The results obtained in this work allowed observing the positive and significant effect of hulling to crambe oil extraction. The absence of hull resulted on maximum yield of oil extracted.KEYWORDS: crambe, dehulling, extraction yield, mechanical pressing, extraction efficiency.

Peeling of crambe fruits, besides increasing the yield of mechanical oil extraction, can increase its apparent specific mass from about 330 to 700 kgm −3 , reducing transport and storage operating costs, as well as increasing cake protein content. However, there is no information on the quality of the oil extracted from the stored unpeeled crambe. This study aimed to assess the possible effects of peeling fruits submitted to different storage systems. For nine months, peeled and unpeeled crambe fruits were stored in conventional (permeable) and hermetic packages and water content, fatty acid, and acidity and oil peroxide indices were monitored. The experimental design was a completely randomized design in a 2 x 2 x 3triple factorial, with three replications. After analysis of variance, the mean data were compared by the Tukey's test, being considered significant when p<0.05. The results showed that peeled crambe had better conservation in relation to that unpeeled, mainly when submitted to the hermetic storage system.