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Scientific, Health and Social Aspects of the Food Industry Part 4

Tham khảo tài liệu 'scientific, health and social aspects of the food industry part 4', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Novel Fractionation Method for Squalene and Phytosterols Contained in the Deodorization Distillate of Rice Bran Oil 79 From these results it is suggested that the squalene was not oxidized under these conditions. Therefore it was found that the present silica gel-SFC with the addition of silica gel as a stationary phase into the supercritical vessel to create a chromatographic system had a higher selectivity than mere SFE. The present silica gel-SFC is expected to become a very useful technique for concentrating squalene from the deodorization distillate of RBO as shown in Fig. 3. 6.2.2 Condensation of phytosterols from the deodorization distillate 6.2.2.1 Condensation of phytosterols by SFC The composition of the residue with PV of 3.0 meq kg recovered by SFC with silica gel packed as a stationary phase under the conditions of 30oC 100 kg cm2 7 mL min and 5 h was 10.4 phytosterols 3.9 Toc 48.6 TG and 37.1 DG FA. In addition the residue recovered from the procedure described in 6.1.2.1 contained 17.3 phytosterols under the following conditions 30oC 220 kg cm2 7 mL min and 7 h. From these results it was considered that SFC did not suit the separation of phytosterols from a mixture of phytosterols TG DG and FA which have nearly the same polarities although SFC was suitable for the extraction of compounds with lower polarity such as a squalene. Then we examined solvent fractionation to concentrate the phytosterols from the deodorization distillate. 6.2.2.2 Condensation of phytosterols by solvent fractionation The residual fraction shown in Fig. 3 contained 15.7 phytosterols in 4.5 g of recovered residue. The 4.5 g of residue remaining in the vessel packed with silica gel were extracted with ethanol and then saponified by refluxing for 4 h with 3 mL of 25 potassium hydroxide aqueous solution and 40 mL each of ethanol and hexane. After the saponification the reactant was separated into a hexane layer and a hydrated ethanol layer. The unsaponifiable components thus .