The interesterification yield (IY) and changes in fatty acid positional distribution of selected butter fat triacylglycerols were investigated, using a wide range of commercial microbial lipases and organic solvent media. The interesterification of butter fat by lipase from Mucor miehei was carried out in hexane, hexane-chloroform, and hexane-ethyl acetate; the results showed that the addition of 30% of either chloroform or ethyl acetate to the hexane resulted in a 23% increase in the IY. The interesterification of butter fat in a microemulsion co-surfactant system, containing Brij 35 as surfactant and 1-heptanol as co-surfactant, resulted in an increase in the triacylglycerols that contain C18:0 at sn-2 position, located originally at sn-1,3 positions, with a concomitant interchange with C14:0 and C18:1 at the same position. The interesterification of butter fat by lipase from Rhizopus niveus, in a phosphatidylcholine reverse micellar system, showed an increase in C16:0 at the sn-2 position, with a concomitant decrease in the proportion of small chain fatty acids (C4-C10:0); however, the interesterification of butter fat in co-surfactant free microemulsion systems, containing hexane and ionic (phosphatidylcholine) and non-ionic (sorbitol monostearate and polyoxyethylene sorbitan monostearate) surfactants, showed that the interesterified selected triacylglycerols were enriched with C18:0 and C18:1, originally located on sn-1,3 position, at sn-2 position with concomitant interchange with C12:0, C14:0 and C16:0, originally located at the same position. The interesterification of butter fats, in co-surfactant free microemulsion system, by four microbial lipases showed that those catalyzed by lipase from R. niveus demonstrated a 46% increase in the proportion of C18:1 at sn-2 position whereas those catalyzed by enzymes from M. javanicus, R. delemar and M. miehei were enriched with C16:0 at the same position, by 21%, 35% and 41%, respectively. In addition, lipase from
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.41762 |
| Date | January 1994 |
| Creators | Safari, Mohammad |
| Contributors | Keymasha, S. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Food Science and Agricultural Chemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001396023, proquestno: NN94710, Theses scanned by UMI/ProQuest. |
Page generated in 0.0024 seconds