Extraction Of Apple Seed Oil And Analysis Of Its Physical-chemical Properties And Fatty Acid Composition

Apple seeds are one of the main components in apple pomace, which may be 3.1% in apple pomace. Plenty of dry apple seeds can be obtained by drying and separating apple pomace. It is proved that the rate of apple seed oil is commonly 22— 27% in apple seed, and 90% of fatty acids is unsaturated fatty acids, especially linoleic acid, which is essential fatty acids for human as having important functions for human health, accounting for 46-52% of fatty acids. However, the conjunction linoleic acid is the main functional component of linoleic acid. Therefore, apple seed oil has important functions for human health.The study using fuji and new red star apple seeds as the material, focuses on extraction of apple seed oil and analysis of its physical-chemical properties and fatty acid composition. It supplies a theoretic basis and optimum processing technics for empoldering and utilizing apple seed oil, and then it provides another method for making use of apple pomace synthetically.The results of the study are the followings.(1) The physical parameters of fuji apple seed are as follows: bulk density and weight of 1000 granules are 574.0g/L and 42.5g, respectively. The content of moisture, kernel, crude fat, crud protein are 7.65%, 74.3%, 23.69% and 48.85%, respectively. The phy- sical parameters of new red star apple seed are as follows: bulk density and weight of 1000 granules are 529.7g/L and 35.5g, respectively. The content of moisture, kernel, crude fat, crud protein are 9.43%, 70.1%, 24.32% and 49.55%, respectively.(2) Petroleum ether (30⁶0℃) is the optimum solvent for extracting apple seed oil. Among the four oil extracting method, the effect of ultrasonic assisted extraction and supercritical carbon dioxide fluid extraction (SFE-CO2) are better than the other two. Under the condition of the fixed frequency of 20KHz, the optimum condition of ultrasonic assisted extraction are as follows: ultrasonic time and power are 25min and 325W, respectively. Solvent dosage (liquid-solid ratio, mL/g) is 5.5. And the cooling water is 10℃. The yield ratio of fuji and new red ster apple seed oil are 22.32% and 23.55% in the optimum condition, respectively. SFE-CO₂ are performed in a pilot plant using saturated alcohol as cosolvent (up to concen- trations of 5%, mL/g) at theoptimum conditions as the following: extracting pressure, separating pressure, extracting temperature, CO2 flux and extracting time are 20MPa, lOMPa, 45'C, 30Kg/h and 3.0h, respectively. The yield ratio of fuji and new red ster apple seed oil are 21.73% and 20.63% in the optimum condition, respectively.(3)It is testified by determining the physical-chemical properties of apple seed oil and then comparing them that the effect of ultrasonic assisted extraction and supercritical carbon dioxide fluid extraction (SFE-CO2) are still better than the other two among the four oil extracting method. The content of moisture and volatile, specific gravity (20/4°C) , refractive index (n20), acid value, saponification value, peroxide value (12% )? iodine value and the content of lecithoid of fuji apple seed oil extracted by ultrasonic assisted extraction are 0.042%, 0.904,1.4632, 6.158mg/g, 172.407, 0.011 104.83 and 0.024%, respectively. The ones of new red star apple seed oil extracted by ultrasonic assisted extraction are 0.045%, 0.903, 1.4642, 6.349mg/g, 162.146, 0.081 96.79 and 0.132%, respectively. The ones of fuji apple seed oil extracted by SFE-CO2 are 0.042%, 0.904,1.4740, 5.074mg/g, 157.778,0.058 121.56 and 0.004%, respectively. The ones of new red star apple seed oil extracted by SFE-CO2 are 0.043%, 0.902, 1.4722, 5.275mg/g, 160.016,0.062 119.64 and 0.003%, respectively.(5) Apple seed oil is rich in unsaturated fatty acids. The content of them in fuji and new red star apple seed oil are always 87.50—90.05% and 89.60—90.25%, respect-tively. But the most proportion are oleic acid and linoleic acid. They usually account for 86.54—88.89% and 88.55—89.27% in fuji and new red star apple seed oil, respecttive-ly. Linoleic acid in fuji and new red star apple seed oil, which has important functions for human health, are 46.56—51.40% and 46.23—50.70%, respectively.