PRELIMINARY STUDIES ON THE ENZYMATIC TREATMENT OF COTTONSEED FOR HIGHER OIL YIELD

Document Type : Original Article

Authors

Fats and Oils Department, National Research Centre, Cairo, Egypt

Abstract

Enzymatic pretreatment of oilseeds prior to oil extraction is an alternative to
the thermal/hydrothermal treatment carried out in the industry to degrade the cell
walls. In this work cottonseed flakes were enzymatically treated with cellulase,
hemicellulase, and pectinase. The enzyme concentrations investigated were 1, 2,
and 3%, at moisture: cottonseed flakes ratio of 5.5:1, 7:1and 10.5:1 (w/w) for 3 and
6 hours.The pH and temperature of the reactions were those stated by the
manufacturers. Pectinase proved the most efficient of the three enzymes followed by
cellulase, extracting ca. 45% and 40% oil, respectively, from the treated flakes,
compared to 37% extracted oil from nontreated cottonseed flakes. All treatments
resulted in highly significant differences (P<0.001) compared to nontreated flakes.
Enzyme mixtures were formulated between pectinase : Cellulase (1:1 ,w/w) and
pectinase : cellulase: hemiceliulase (0.66 : 0.66 : 0.66, w/w). Percentage increase in
oil extractability was in the following order pectinase : cellulase > pectinase >
pectinase : cellulase: hemicellulase > cellulase> hemicellulase yielding 28% , 22% ,
22 % and 10.5%, respectively. Iodine value, acid value and total gossypol of all the
resulting oils were examined. The fatty acid composition of the oils resulting from the
treatments together with the iodine value show that the ratio of saturated to
unsaturated fatty acids were either the same as the untreated oil or the saturation
increased slightly.

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