Technological aspects of Egyptian lupinseed oil

ABSTRACT

Crude oils obtained from Lupine seed of Giza 1, Giza 2 and Balady were treated by neutralization and bleaching. Fuller's earths, mixture of Fuller's earth and charcoal as well as bleaching by heat alone were used in the bleaching process. The obtained results revealed the following 1.The effect of neutralization on colour was more pronounced. Blue pigments were removed completely, while the red units of crude lupine seed oil of Giza 1, Giza 2 and Balady were 15, 14 and 9 respectively. The red colour of all samples was reduced by neutralization as it reached 13.1, 7.5 and 8.5 respectively. However, melting point of all samples remained stable. 2. Free fatty acids of crude oil of Giza 1, Giza 2 and Balady decreased after neutralization. Meanwhile, the peroxide value of all crude lupine seed oils increased. 3. Unsaponifiable matter and titer point decreased slightly by neutralization of crude lupine seed oils. Besides the iodine value of crude oil of Giza 1, Giza 2 and Balady was found to decrease from 117.97, 110.87 and 130.77 to 113.56, 107.53 and 126.22 respectively for the same neutralized oils. 4. Bleaching of neutralized oil of Giza 1, Giza 2 and Balady lupine by 2% Fuller's earth caused an increase in the free fatty acids content. The increase was more pronounced in lupinseed oil of Giza 1. The free fatty acids were 0.08, 0.08 and 0.09% for neutralized oil of Giza 1, Giza 2, and Balady respectively. After bleaching they became 0.15, 0.10 and 0.10% respectively. 5. A mixture containing 95% Fuller's earth and 5% charcoal in an amount of 3% was more active in bleaching than using 2% of Fuller's earth alone. 6. Heat bleaching method was found to be more effective in removing red colour units from lupine seed oils compared with 3% mixture of fullers earth and charcoal. The colour of oils obtained from Giza 1, Giza 2 and balady bleacher by 3% huller's earth and charcoal were as 8.0, 4.5 and 5.6 Lovibond red units respectively, while were 6.7, 4.1 and 5 when bleaching was carried out by heat bleaching method: