Study On The Extraction Process Of Seed Oil From Pomelo And Its Properties Of Physical-chemical And Main Fatty Acid Composition

Pomelo seed oil contains plenty of unsaturated fatty acids,such as oleic acid,linoleic acid and linolenic acid.Unsaturated fatty acids with high nutritional value,which exists in vegetable oil,can not be synthesized by organism.In our county,large quantities of oil resources had been imported.Therefore,it is important to exploit new oil resources.In the research,the extraction process,nutrition content,physical and chemical properties,fatty acid composition had been systematically studied by using Citrus grandis var.shatinyu and Citrus grandis var.jiang yong as materials.The main results were as follows:(1)Pomelo seed oil from Citrus grandis var.shatinyu and Citrus grandis var.jiang yong had been obtained by combining methods of microwave-assisted extraction and ultrasound-assisted extraction.Based on the single-factor experiment,the optimized extraction parameters of seed oil from Citrus grandis var.shatinyu had been obtained by the response surface experiments.The optimal extraction conditions were:microwave-assisted extraction with hexane as the extraction solvent,extraction temperature 65 ?,extraction time 16 min,solid to liquid ratio 1:10.Under the optimal conditions,the extraction yield of seed oil was 46.53%.It was continued to be extracted by ultrasound-assisted method which extraction conditions were:power 74 W,extraction temperature 48?,extraction time 40 min.Under such conditions the extraction ratio was 48.94%.Citrus grandis var.jiang yong of microwave-assisted extraction process up to parameters were as follows:extraction temperature 63?,extraction time 14 min,solid to liquid ratio 1:10.Under the optimal conditions,the extraction yield of seed oil was 42.76%.Then,it was extracted by ultrasound-assisted method which extraction conditions were:power 74 W,extraction temperature 48?,extraction time 40 min.Under such conditions the extraction rate was 44.92%.The results of experiment showed that Citrus grandis var.shatinyu seed oil and Citrus grandis var.jiang yong seed oil extraction yield were improved by 2.41%and 2.16%.(2)The related nutrition content of Citrus grandis var.shatinyu seeds and Citrus grandis var.jiang yong seeds had been studied.The content of crude protein and crude fat in Citrus grandis var.shatinyu seeds were respectively 30.76%and 48.55%.The content of crude protein and crude fat from Citrus grandis var.jiang yong seeds were respectively 32.18%and 46.98%.Thus,the crude protein content of pomelo was lower than that of soybeans,but the crude fat content was higher.(3)The two kinds of pomelo seeds oil were also studied on the physical and chemical properties.Citrus grandis var.shatinyu seed oil was bright yellow,clear and transparent,grease a rich flavor with good mobility at room temperature.The physical and chemical properties were presented:relative density 0.94 g/mL,peroxide value 5.41 mmol/kg,acid value 1.08 mgKOH/g,saponification value 190.33 mgKOH/g,iodine value 94.53 g/100g,respectively.Citrus grandis var.jiang yong seed oil was light yellow,clear and transparent,grease a rich flavor with good mobility.And the physical and chemical properties appear below:relative density 0.89 g/mL,peroxide value 5.02 mmol/kg,acid value 1.13 mgKOH/g,saponification value 184.27 mgKOH/g,iodine value 90.80 g/100g,respectively.Compared with peanut oil,soybean oil and sesame oil,seed oil of Citrus grandis var.shatinyu and Citrus grandis var.jiang yong could be further refined and utilized.(4)The main fatty acid content of Citrus grandis var.shatinyu and Citrus grandis var.jiang yong seed oil were studied by gas chronographs.The contents of linoleic acid,oleic acid and palmitic acid in the main fatty acid of Citrus grandis var.shatinyu and Citrus grandis var.jiang yong seed oil were respectively 41.03%,20.95%,27.13%and 39.29%,21.45%,26.67%.