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در این تحقیق به‌منظور مدل‌سازی شبکه‌های عصبی مصنوعی فرایند استخراج روغن از دانه‌های سیاه‌دانه به کمک پیش‌تیمار مایکروویو از زمان‌های مختلف فرایند (90، 180 و 270 ثانیه) و توان‌های مختلف (180، 540 و 900 وات) استفاده گردید. بعد از اعمال این پیش‌تیمارها، روغن دانه‌ها با پرس مارپیچی و با سرعت‌های متفاوت (11، 34 و 57 دور در دقیقه) استخراج شد و میزان راندمان استخراج، اندیس اسیدی و اسیدیته، رنگ و پایداری اکسیداتیو نمونه‌ها مورد بررسی قرار گرفت. جهت پیش‌بینی روند تغییرات از ابزارشبکه‌های عصبی مصنوعی در نرم‌افزار Matlab R2013a استفاده شد. با بررسی توپولوژی‌های مختلف شبکه‌ عصبی، شبکه‌ پس‌انتشار پیشخور با توپولوژی‌های 3-10-5 با ضریب همبستگی بیشتر از 995/0 و میانگین مربعات خطای کمتر از 0005/0 و با بکارگیری تابع فعال‌سازی تانژانت سیگموئید هیپربولیکی، الگوی یادگیری لونبرگ– مارکوات و چرخه یادگیری 1000 به‌عنوان بهترین مدل‌ عصبی مشخص گردید. نتایج حاصل از مدل‌های بهینه انتخاب شده نیز ارزیابی گردید و این مدل‌ها با ضرایب همبستگی بالا )بیش از 949/0( قادر به پیش‌بینی روند تغییرات بودند.

مرسوم‌ترین روش‌های استخراج روغن از دانه‌های روغنی، استفاده از پرس و حلال می‌‌باشد. در پژوهش حاضر، تاثیر درجه حرارت پخت (70، 80 و 90 درجه سانتی‌گراد) و رطوبت دانه‌های خروجی از دیگ پخت (7، 5/7 و 8 درصد) بر برخی از خصوصیات شیمیایی روغن آفتاب‌گردان از جمله میزان مواد ریز نامحلول در روغن، اسیدیته، میزان رطوبت، پروتئین و روغن کنجاله بررسی شد. تجزیه و تحلیل آماری و بهینه‌سازی فرایند به روش سطح پاسخ انجام شد. نتایج نشان داد که با افزایش درجه حرارت پخت میزان مواد ریز نامحلول و اسیدیته روغن افزایش ولی میزان رطوبت و روغن در کنجاله کاهش یافت. با افزایش میزان رطوبت دانه‌های خروجی از دیگ پخت از میزان مواد ریز نامحلول روغن کاسته ولی بر میزان اسیدیته روغن افزوده شد. با توجه به نتایج بهینه‌سازی فرایند می‌توان بیان نمود که اعمال شرایط دمایی در حدود 70 سانتی‌گراد و با رطوبت 73/7 و 65/7 درصد دانه‌های خروجی از دیگ پخت منجر به تولید محصولی با حداقل میزان اسیدیته و مواد ریز نامحلول در روغن و کنجاله‌ایی با کمترین میزان روغن گردید.

In this research, in order to optimize the extraction process of Ethanolic extract of barberry fruit, the increase and optimization of the conditions for the extraction of anthocyanin's and bioactive compounds by means of intermittent electric field pre-treatment from three levels of electric field intensity (0.5, 1.75 and 3 kV / cm) and 3 levels of number of pulses (15, 30 and 45); then with ethanol solvent was used to extract their extracts and the amount of flavonoids, total anthocyanin, DPPH, total phenolic compounds, iron regeneration capacity, vitamin C and acidity compared to control (no treatment) Was studied. The results showed that the total phenol content of the extract decreased by increasing the number of pulses and reducing the intensity of the pulsed electric field applied to the sample. The increase in the electric field strength and the number of pulses initially increased the flavonoid content, DPPH and iron ion recovery capacity, but with the increase of these variables, these three parameters decreased. Also, with increasing of these parameters, the anthocyanin level and vitamin C content increased. The acidity of the sample was reduced and then increased by increasing the electric field strength and applied pulse number. Regarding the results of the process optimization, it can be concluded that the electrical field intensity of 2.003 kV / cm and applying 29 pulses can increases the antioxidant properties of the produced product compared with the control sample. [ABSTRACT FROM AUTHOR]

Hawthorn (Crataegus spp.) Is a rich source of natural antioxidants, especially flavonoids and anthocyanins, and these bioactive compounds have various beneficial effects on health and well-being. In this study, extracts of hawthorn fruits were used with ultrasound (for 30 min), microwave (150 s) and ultrasound- microwave (30 min ultrasound + 150 s microwave) and after applying these supplements, the extract of fruits with Ethanol was extracted and one sample was selected as a control without pre-treatment. The total phenolic compounds, the ability to inhibit DPPH free radicals, iron regeneration capacity, acidity and some of the important compounds (by gas chromatography / mass spectrometry) of the samples were investigated. Statistical analysis and process optimization were performed completely randomly using SAS software. The results showed that the use of different pretreatments resulted in increasing the total phenolic compounds, the ability to inhibit DPPH free radicals and iron regeneration capacity in extracted extracts, so that the samples from the pretreatment of ultrasound-microwave were 9.89 The percentage of total phenol was higher. The results of the analysis of the data from the acidity of the samples showed that the pre-treatment type did not have a significant effect on the acidity of the samples (p>0.01). The use of microwave ultrasound pre-treatment resulted in a greater increase in the compounds in the extract and the base-2-ethylhexyl-phthalate combination was the most recognizable combination in the extracts. In the end, it can be stated that microwave ultrasound was the best pretreatment for preparation of extract hawthorn fruit. [ABSTRACT FROM AUTHOR]

There are various methods available to assist in the oil extraction from oil seeds, one of which is the use of ultrasonic waves. In this research, in order to optimize the process of extraction of oil from the peanut using ultrasound pretreatment, three levels of sonication time (0, 30 and 60 min) were used. After using these pretreatments, the oil of seeds was extracted with screw press with different rotation speeds (11, 34 and 57 rpm), then parameters including oil extraction yield, acidity, oxidative stability, peroxide, total phenolic compounds and refractive index of the samples were studied. Statistical analysis and process optimization was performed with the use of response surface methodology (RSM). The results showed that with increasing sonication time, oil extraction yield and phenolic compounds increased first and then decreased. By increasing the speed of the screw press, the amount of oil extraction yield and oxidative stability decreased, but the acidity, peroxide and total phenolic compounds increased. Increasing the sonication time also resulted in increased acidity, oxidative stability and peroxide reduction. On the other hand, it was determined that the parameters did not affect the rate of refractive index and its rate was 1.471 for all measured samples. According to the results of process optimization, it might be stated that with applying 60 minutes of ultrasound time and screw-rotation speed of the press of 21.73 rpm can provide a 0.766 utility for extracting oil from peanut. [ABSTRACT FROM AUTHOR]