تاثیر نسبت روغن و مقدار امولسیفایر بر خصوصیات نانوامولسیون روغن دانه چیا

در این پژوهش راندمان استخراج، ترکیب و میزان اسیدهای چرب موجود در روغن دانه چیا و فعالیت آنتی‌اکسیدانی آن مورد بررسی قرار گرفت. همچنین نانوامولسیون‌های این روغن در سه سطح روغن به آب(20%، 35% و 50%) و در سه سطح امولسیفایر به روغن(5%، 10% و 15%) تولید شد. خصوصیات تمامی 9 تیمار تولید شده شامل اندازه و توزیع ذرات،راندمان درون پوشانی و میزان خاصیت آنتی‌اکسیدانی مورد ارزیابی قرار گرفت. همچنین میزان رهایش نانوامولسیون‌ها به مدت 7 هفته بررسی شد. در این مطالعه روغن دانه چیا با روش پرس سرد استخراج گردید و راندمان استخراج آن 05/ 27% اندازه گیری شد. برای ارزیابی ترکیب اسیدهای چرب این روغن از دستگاه کروماتوگرافی گازی استفاده گردید. این روغن دارای 47.09% لینولنیک اسید بود و میزان خاصیت آنتی‌اکسیدانی آن به‌طور میانگین (88.43%) اندازه‌گیری شد. نتایج آزمون‌های انجام شده بر روی نانوامولسیون‌ها نشان داد که که با افزایش میزان روغن نانوامولسیون‌ها، اندازه ذرات و خاصیت آنتی‌اکسیدانی و رهایش افزایش یافته و راندمان درون پوشانی کاهش می‌یابد. همچنین با افزایش نسبت امولسیفایر به روغن در نانوامولسیون‌ها راندمان درون پوشانی و خاصیت آنتی‌اکسیدانی افزایش یافته و اندازه ذرات و رهایش کم می‌شود. در نتایج به‌دست آمده از این آزمون‌ها کمترین اندازه ذرات 14.08 نانومتر بود و بیشترین راندمان درون پوشانی 96.40% به‌دست آمد. فعالیت آنتی‌اکسیدانی نمونه‌ها در محدوده 5.61% تا 21.43% ارزیابی شد. همچنین میانگین رهایش نمونه‌ها در پایان 7 هفته بررسی به نزدیک 18 درصد رسید. در طی نگهداری تیمارها به مدت پنج ماه، کاملا پایدار بودند.

the effect of oil to water ratio and emulsifier amount on the properties of chia seed oil nanoemulsion

1]introduction: nowadays, various methods have been developed to transfer and improve the absorption of lipophilic compounds in food in the form of coating. colloidal emulsion-based systems are widely used in commercial systems. chia seed oil is an oil rich in unsaturated fatty acids, especially omega 3 and omega 6, which can be used as the oily phase of nanoemulsions. the aim of this study was to investigate the fatty acid composition of chia seed oil and the effect of oil to water ratio and emulsifier on the properties of nanoemulsions of this oil. materials and methods: clean chia seeds were purchased as a pack from zistfa company and all other chemicals were purchased from marack, pars shimi and dr. majelli companies. by using the oil set machine, the seeds were treated by cold pressing method and oil extraction efficiency was calculated .gas chromatography (gc) was used to identify and measure the fatty acid composition of chia seed oil. in this study, nanoemulsions were produced in three levels of oil to water (20%, 35% and 50%) and in three levels of oil emulsifier (5%, 10% and 15%).to produce nanoemulsions, the aforementioned ratios were first calculated and determined .then, weigh the tweens 20 and 80 with chia seed oil and water and mix the emulsifiers with the chia seed oil on the stirrer. then a mixture of 20 and 80 tweens and oil was added dropwise to the weighed distilled water. the mixture was stirred gently by a magnet. after this step, the mixture is placed in the refrigerator to reduce its temperature. after this time, it was placed in an ice bucket and placed in an ultrasonic homogenizer for 9 minutes at a power of 300 watts to form nanoemulsions. then, the properties of nanoemulsions including particle size and distribution, coating efficiency and antioxidant properties were evaluated. vasco model dls (dynamic light scattering) was used for the particle size. the particle size of nanoemulsions was determined by this device using dynamic light diffraction method. dpph method was used to measure the antioxidant activity of oils and nanoemulsions and the antioxidant activity was calculated by using the formula. to evaluate the efficiency of coating of nanoemulsions, the amount of surface oil and total oil was measured and the efficiency was calculated by using the formula. the release rate of nanoemulsions was evaluated for 7 weeks. the tests were performed in three replications. experimental data were analyzed in a completely randomized design with factorial test and duncan test was used to compare the mean data. software (excel, 2010) was used to draw the graphs results and discussion: according to the results obtained in this study, it can be said that chia seed oil contains a high percentage of unsaturated fatty acids and has a very high level of antioxidant properties (88.43%), which has antioxidant properties in the structure of nanoemulsions. oil is better preserved in water. other results showed that with increasing oil content of nanoemulsions, particle size, antioxidant properties and release increased and the coating efficiency decreased. also, by increasing the ratio of emulsifier to oil in nanoemulsions, the coating efficiency and antioxidant properties increase and the particle size and release decreases. in the results obtained from these tests, the minimum particle size was 14.08 nm and the highest coating efficiency was 96.40%. the antioxidant activity of the samples was evaluated in the range of 5.61% to 21.43%. also, the average release of samples at the end of 7 weeks of the study reached nearly 18%. during storage, the treatments were quite stable for five months, which could be due to the low particle size and low release of samples. considering the mentioned advantages, using nanoemulsions of this oil is a suitable option for enriching beverages.