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برشته کردن یکی از فرآیندهایی است که مقدار ترکیبات مغزهای خوراکی را تغییر می‌دهد. هدف از این مطالعه بررسی تاثیر شرایط برشته کردن بر میزان محتوی آلفا و گاماتوکوفرول بود. در مطالعه حاضر، اثر دما (120 و 150 درجه سانتی‌گراد)، و زمان (صفر، 20، 30 و 40 دقیقه) برشته کردن بر میزان آلفاتوکوفرول و گاماتوکوفرول باقی مانده در چهار مغز بادام درختی، فندق، بادام‌زمینی و پسته مورد بررسی قرار گرفت. برشته کردن یکی از روش‌های معمول فرآوری مغزهای خام بوده که می‌تواند بر مقدار توکوفرول مغزها اثر بالایی داشته باشد. نتایج نشان دادند که مقدار آلفاتوکوفرول بادام درختی در دمای 120 درجه سانتی‌گراد و گاماتوکوفرول در هر دو دمای اعمالی در طول 20 دقیقه ابتدایی برشته کردن افزایش یافته ولی با ادامه فرآیند تا 40 دقیقه مقدار آن کاهش یافت. در فندق، بادام‌زمینی و پسته نیز مقدار آلفا و گاماتوکوفرول تا دقیقه 20، افزایش یافته ولی در ادامه حرارت‌دهی کاهش یافت. به‌طور کلی در دمای 150 درجه سانتی‌گراد، پس از 20 دقیقه میزان توکوفرول مغزها شروع به کاهش کرد در حالی که در دمای 120 درجه سانتی‌گراد روند کاهشی پس از 30 دقیقه نمود یافت. افزایش مقدار توکوفرول‌ها در ابتدای برشته کردن به سبب آسیب دیواره‌های سلولی بوده و توکوفرول‌های متصل به ترکیباتی همچون فسفولیپیدها با سهولت بیشتری خارج می‌شوند. در ادامه برشته کردن، به دلیل حساسیت این ترکیبات به حرارت، تجزیه حرارتی آنها رخ داده و کاهش می‌یابند.

The stability of curcumin and its encapsulation efficiency in emulsion are among the most important factors determining its bioavailability and absorption in the body. For this purpose, parameters affecting these two factors, including time, pH, and cellulose concentration, were used as input variables in the present study. Curcumin stability and encapsulation efficiency were used as response variables in artificial neural networks and decision tree algorithms. In this regard, cellulose nanocrystal obtained from acid hydrolysis was used to prepare curcumin Pickering emulsion with oil:water ratio of 5:95 and cellulose concentration 1, 1.5, 2, 2.5, and 3% (w/v) and the encapsulation efficiency and stability of curcumin were measured during 8 days. The results showed that the encapsulation efficiency significantly increased as cellulose concentration increased. Encapsulation efficiency at pH 7 was higher than at pH 2 (p≤0.05). The curcumin content in the emulsions prepared at pH 2 drastically decreased during storage, while it was less degraded in emulsions at pH 7 after 8 days of storage. The modelling results for curcumin stability and encapsulation efficiency based on R2and RMSE% statistics showed that MLP 3 - 6 -1 (R2=0.99; RMSE%=10.00) and RBF 2 - 6 -1 (R2=0.99; RMSE %=9.99) were had more accuracy than other models. Finally, the results showed that the artificial neural network algorithm performed better than the decision tree in predicting cellulose Pickering emulsions' encapsulation efficiency and curcumin stability. [ABSTRACT FROM AUTHOR]

In this study, the possibility of microencapsulation of Oliveria decumbens essential oil (ODEO) was investigated on the microstructure of microfibers. The fibers were produced using polymeric cellulose acetate (CA) and the essential oil was added to the electrospun solution at different concentrations (0, 15, 25, 35 and 45%). The samples were analyzed using SEM and FTIR. SEM micrographs showed that all of fibers had homogenous structure without nodes. However addition of ODEO at 45% significantly increased the diameter of fibers compared to control sample. FTIR results of control and 45% ODEO fibers showed that in both samples there are distinct peaks of CA, and in fiber containing essential oils in addition to the CA peaks, the peaks in the 812 belong to the compound containing para and in 771 and 899 are related to compounds containing meta bonds. Both of them represent the aromatic compounds of the essential oil. The results of the antimicrobial activity of the fibers showed that the inhibition of the ODEO fibers against Staphylococcus aureus was generally higher than E. coli. Antimicrobial activity was increased with increasing ODEO concentrations. [ABSTRACT FROM AUTHOR]

In the current study, the nanofiber gel of tomato pomace was prepared using a super disk grinder device available at Nano Novin Polymer Co., Iran. Three different concentrations (2, 4 and 6%) of the gel prepared and rheological tests including amplitude sweep, frequency sweep, temperature sweep, and flow behavior were done. DLS results showed that the average diameter of tomato nano-gel was around 38 nm. The power law model was chosen as the best model for describing flow behavior data. All samples showed a shear-thinning behavior that viscosity decreased with increasing shear rate. A hysteresis loop was observed in all samples which confirmed the thixotropic characteristic of gels. Based on amplitude sweep data, elastic modulus (G') was higher than viscous modulus (G"), in addition, crossover points of all gels showed that the flowability decreased with increasing concentrations. Based on frequency data, G' in all concentrations was higher than G" and both parameters increased with increasing concentration from 2 to 6%. In lower frequencies, all gels showed solid-like behavior while G' and G" increased with increasing frequency indicating the weakening of the gel network. G' and G" gradually decreased with increasing temperature from 5 to 50 ºC which confirmed that all gels were weakened at high temperatures, but in the cooling cycle, all gels recovered their structures and no remarkable hysteresis was observed. [ABSTRACT FROM AUTHOR]

Physical and antibacterial properties of ultrasound assisted emulsions from two essential oils (Cuminum cyminum and Oliveria decumbens) at concentrations of 1, 3, 5, 10 and 15% were studied. The results showed that all emulsions were stable after centrifugation. Although the samples were stable after heatcool cycles, they became unstable at the freeze-thaw cycles. Emulsion samples with concentrations of 10 and 15%, were stored at 45 ºC for 35-days were unstable and became two-phase. Measuring the turbidity of emulsion samples with a spectrophotometer showed that with increasing concentrations of dispersed phase, the emulsion turbidity increased. Both emulsions showed antibacterial activity. But the C. cyminum emulsions showed higher inhibition zones against Escherichia coli, while O. decumbens emulsions represented higher inhibition zone against Staphylococcus aureus. Generally, the inhibition zone diameters of both emulsions increased dose dependently. [ABSTRACT FROM AUTHOR]