Miscella Refining of Isopropanol Extracted Cottonseed Oil

Abstract

A technologically feasible cottonseed oil-isopropyl alcohol (IPA) miscella refining process was developed to produce Prime Bleachable Summer Yellow (PBSY) quality cottonseed oil. Individual steps necessary to refine cottonseed oil-IPA miscella were determined and improved The miscella was first neutralized with 20 Baume (Bey caustic solution (50% excess) using a homogenizer. After centrifigation to remove soapstock, the two remaining liquid layers were separated and desolventized. The refined oils from bottom and top layers were then water washed using 12.5 and 20% hot water (w/w), respectively, Water washing efficiently recovered the oil from the top miscella layer and reduced soap and phosphorus contents. The water washed and dried o i l f o m the bottom and top layers were treated with 0.5 and 4% (w/w) acid-activated bleaching clay, respectfvely. Good quality bleached oil was then obtained. However, the quality of bleached oil producedfrom the bottom layer was better than that of the top layer. Comparative experiments with both IPA and hexane miscellas showed that quality of the refined oil f o m cottonseed oil-IPA miscella is as good as that producedfr.om the cottonseed oil-hexane miscella using the process developed in this study.

THE QUALITY OF VEGETABLE OIL FROM THREE VARIETIES OF SUNFLOWER SEEDS (HELIANTHUS ANNUUS)

“…In more concentrated miscellas (70%), the silica particles have less mobility and then interact with other less polar components as fatty acids. Chau et al (1996) reported a similar behavior in the refining of cotton oil with miscellas. The lost oil was 17% with hexane and 28% with isopropyl alcohol.…”

“…Malonaldehyde is polar and will likely interact with isopropyl alcohol rather than with hexane. Nevertheless, the three varieties showed acceptable levels of malonaldehyde content according to the TBA essay pointed out by Chau et al. (1996) as less than 0.1 ppm.…”

“…The silica–isopropyl alcohol interaction has been observed during cotton oil refining with miscellas. The isopropyl alcohol‐extracted oil was more acidic than the one extracted with hexane, 0.180 versus 0.040 (as % of oleic acid) respectively, and the acidity levels were higher in crude oils than in refined ones (Chau et al. 1996).…”

“…more acidic than the one extracted with hexane, 0.180 versus 0.040 (as % of oleic acid) respectively, and the acidity levels were higher in crude oils than in refined ones (Chau et al 1996).…”

“…Oil quality and reduced refining losses make miscella refining process attractive and economical compared with the conventional caustic refining process. The advantages of miscella refining are lower neutral oil loss, minimal color problems due to temperature and time, less caustic required, lower neutral oil entrapment in soapstock and less soapstock in oil (Chau et al 1996). The objective of this work was to evaluate three new varieties of sunflower in function of quality oil obtained with two solvents.…”