ریز پوشانی چند لایه لیمونن بر پایه جذب الکترواستاتیک و ارزیابی رهایش آن تحت شرایط شبیه‌سازی ‌شده دهان

در این پژوهش از روش جذب لایه به لایه پلی الکترولیت‌های ایزوله پروتئین سویا و نشاسته اصلاح‌شده برای تولید میکروکپسول محتوی لیمونن استفاده شد. ویژگی‌های مورفولوژیکی و ساختاری میکروکپسول‌های تولیدی بررسی گردید. میزان رهایش لیمونن از میکروکپسول‌های تولید شده به‌صورت دو و شش لایه در شرایط دهان مصنوعی در شرایط تنش برشی مختلف (0، 50 و 100 دور در دقیقه) مورد ارزیابی قرار گرفت. نمایه رهایش لیمونن از میکروکپسول‌ها نشان داد لیمونن در میکروکپسول‌های دو لایه با شیب بیشتری نسبت به شش لایه، رهایش یافته و سریع‌تر به حداکثر رهایش می‌رسد زیرا با افزایش تعداد لایه‌های دیواره، رهایش به تاخیر می‌افتد. نتایج به‌دست‌آمده از رهایش لیمونن از میکروکپسول ها نشان داد مدل درجه اول بهترین توصیف را از رهایش داشت و بر اساس معادله کورسمیر-پپاس رهایش لیمونن از میکروکپسول‌ها غالباً از نوع نفوذ بود. همچنین نتایج نشان داد ضریب نفوذ با افزایش تنش برشی، بیشتر شد و ضریب نفوذ در میکروکپسول‌های دو لایه نسبت به شش لایه بیشتر بود.

encapsulated limonene based multi-layer electrostatic adsorption and evaluate its release under simulated oral conditions

introductionefforts have always been made to protect valuable compounds of medicine, food and aromatics materials that are highly sensitive to environmental conditions by the encapsulation method. encapsulation of flavors, in addition to its protection, allows the aromatic substance to be released in a long time, and the time and place of its release can be controlled. to design these protection systems requires detailed information on encapsulation and release methods, the nature of walls and aromatic materials (gunning et al.,1999). for encapsulation of sensitive compounds such as lipophilic materials, it is necessary to produce an emulsion of the desired substance in wall materials such as proteins, polysaccharides or a mixture of them. the important factors in encapsulation are the molecular weight, chemical properties and polarity of the core materials, the properties of the materials of the walls, and finally, the methods used to produce microcapsules. (jafari et al., 2008).the aim of this study was to produce and evaluate the properties of two and six layer multilayer microcapsules containing limonene using soy protein isolate and starch modified by spray drying. the release of encapsulated limonene was investigated under artificial oral conditions under different stress conditions. the results of this study can be used to predict the release rate of the encapsulated flavors and their release conditions.materials and methodssolution preparation: the solution of spi (0-3%) was prepared by methods of huang et al. (2012). the osa starch stock solution (0-2%) was prepared by methods of nilsson and bergens (2007).emulsion’s preparation: the primary emulsion of the optimum spi and secondary emulsion of optimum osa starch concentration prepared by the method of noshad et al (2015).microcapsule production: to prepare the microcapsules, a laboratory spray dryer was used. 180±5 ᵒc, inlet air temperature, 25 (ml/min) feed rate, and 90±10 ᵒc outlet air temperature were used. six layer microcapsules was also prepared in the same conditions (ansarifar et al., 2017)the micro structure, morphology and release of limonene were evaluated and finally by zero order, first order, higuchi, and korsemeyer- peppas models were used to the fitting of experimental data.limonene release: to investigate the release of the encapsulated limonene, the release of these microcapsules (two and six layer) at 37 ° c and ph = 6.8, as well as frequent chewing (0, 50 and 100 rpm) were examined. for the apply of shear stress, an oral simulator was designed and developed by the department of food science and technology of ferdowsi university of mashhad was used. results and discusionthe results of particle size changes of the initial emulsion formed with different levels of soy protein isolate showed that the particle size decreased with increasing the concentration of this protein to 1.5% and then it was increased. the results of zeta potential showed that with increasing the concentration of soy protein isolate to 1.5%, the zeta potential of the samples increased and with more than 1.5%, it did not have much effect on the zeta potential of the samples, which indicates that concentrate of 1.5% soy protein isolate has a good ability to cover surface of limonene particles. similarly, 1.2% of osa starch was determined for the secondary layer.sem images of the microcapsules showed that in the two-layer wall microcapsules have cavities, cracks and shrinkage. in the starting of drying, the rate of moisture lost is high and on the other hand, the wall is not strong enough to withstand the stresses caused by the exit of moisture from the walls, so the microcapsule has cavities. in six-layer microcapsules, a smooth, non-cracked surface was observed, which can be attributed to the wall strength due to the increase in the number of layers.