Abstract:
Phytosterol is a kind of natural active substance, which has broad development prospects and value. With the upgrading of people's health consumption and the rapid expansion of the functional nutrition market, the market demand of phytosterol industry has also increased. Therefore, how to improve the purity of phytosterol to meet the application market needs was an urgent problem to be solved. In this article, crude sterol was used as raw material and ethyl acetate as crystallization solvent. The optimum crystallization conditions were obtained by single factor experiments and response surface experiments. The results showed that the optimal crystallization conditions were obtained as follows: crystallization temperature 23 ℃, cooling rate 0.6 ℃/min, stirring rate 46 r/min, and crystallization times 3. Under these conditions, the total sterol content could reach 99.10%, and the yield was 80.34%. The theoretical analysis results of the response surface were consistent with the predicted values, indicating that the model was reliable. Combined with the actual production, the recovered mother liquor was recycled in the same way as above. The corresponding quality indicators of refined sterol based on relevant standards were analyzed. The sterol crystal form was loose powder without, irritating odor after repeated crystallization. The physical and chemical properties of refined sterol were obtained as follows: acid value 0.49 mg/g, melting point 139 ℃, ash content 0.15%, which met the corresponding standards. The purity of phytosterol can be significantly improved by recrystallization of ethyl acetate, and the corresponding quality characteristics have been better improved. This study is expected to provide a research basis for subsequent high value utilization of phytosterol.