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Introduction Thermal process is the most prominent option for treating foods. During the heat treatment, food nutrients response simultaneously but adversely under pH, temperature, moisture, and other provided conditions. It might result in an irreversible transformation of composition and structure that influences oxidative stability and sensory properties. The use of antioxidants is one of the most common methods to prevent edible oils oxidation. Safety concerns of synthetic antioxidants including tert-butylhydroquinone (TBHQ) as food additives have led to increasing demands for natural ones. Phenolic compounds such as Gallic Acid (GA) and Methyl Gallate (MG) represent to possess markedly high activity to scavenge free radicals which are among the most powerful natural sources of oxidative inhibitors in foods. Apart from their antioxidant activity, GA and MG also exhibit multiple biological characteristics such as anti-atherogenic, anti-spasmodic, and anti-microbial activities. This study aimed to investigate the oxidative stability of the in-use sunflower (S) and palm (P) oils as affected by the GA, MG, (GA+MG), and TBHQ to clarify their antioxidant behavior. Materials and Methods Antioxidants Gallic acid, Methyl gallate and TBHQ (Purity>98%) were purchased from Sigma Aldrich, USA. All solvents and chemicals were provided from Merck, Germany and Sigma Aldrich, USA with analytical grade. Antioxidant-free sunflower and palm oil were prepared from Three Goals factory, Neyshabur, and potatoes (Agria variety) from Fariman region, Khorasan Razavi. Results and Discussion Chemical changes, oxidative stability and quality indices of the in-use sunflower oil (S) and palm (P) (65:35 w.t. %) were evaluated during 8-hour heat treatment at 180 °C through GA, MG, GA/MG (25:75, 50:50 and 25:75) and TBHQ. All experiments were carried out in quadruplicate, and data were subjected to analysis of variance (One-way-ANOVA). Mean data were compared based on Duncan's multiple range test at 5% level (p

نانوفیبر سلولزی اصلاح شده با اسید چرب (MCNF) و آنتی اکسیدان ترت بوتیل هیدروکینون (TBHQ) به فیلم پلی لاکتیک اسید (PLA) اضافه شدند و تأثیر آنها بر ریز ساختار، ویژگی‌های حرارتی، مکانیکی و بازدارندگی فیلم PLA مورد بررسی قرار گرفت. ریز ساختار سطح شکست فیلم‌ها توسط میکروسکوپ الکترونی روبشی نشر میدانی (FE-SEM) مورد مطالعه قرار گرفت. نتایج آزمون پراش اشعه ایکس (XRD) نشان داد که بلورینگی فیلم‌‌های نانوکامپوزیت حاوی MCNF بیشتر از فیلم خالص PLA و فیلم‌های فعال حاوی TBHQ بود. نتایج گرماسنجی پویشی افتراقی نشان داد که با افزودن هر دو ترکیب، دمای انتقال شیشه‌ای و دمای ذوب فیلم ها تغییر می کند. افزودن 3% TBHQ باعث کاهش معنی‌دار (05/0˂p) در استحکام کششی فیلم PLA از 52/10 به MPa 03/6 شد در صورتیکه، استحکام مکانیکی فیلم با افزودن MCNF بهبود یافت. نفوذپذیری نسبت به بخار آب و اکسیژن نیز با افزودن TBHQ و MCNF بترتیب افزایش و کاهش یافت.