فهرست مطالب

پژوهشهای علوم و صنایع غذایی ایران - سال هجدهم شماره 2 (پیاپی 74، خرداد و تیر 1401)

نشریه پژوهش های علوم و صنایع غذایی ایران
سال هجدهم شماره 2 (پیاپی 74، خرداد و تیر 1401)

  • تاریخ انتشار: 1401/04/20
  • تعداد عناوین: 13
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  • زرین نصری* صفحات 179-194

    در این پژوهش تاثیر اندازه ذره و قطر ریشه شیرین بیان بر میزان استخراج اسید گلیسیریزیک با استفاده از التراسونیک بررسی شد. از روش طراحی تجربی فاکتوریل کامل و روش سطح پاسخ برای تعیین سطوح پارامترها و مدل کردن پاسخ استفاده شد. متغیرهای مستقل شامل اندازه ذره ریشه شیرین بیان در سه سطح (120 ≤، 120-60، 60- 35 مش) و قطر ریشه شیرین بیان در سه سطح (cm 3 ≤، 3 -2، 2 -1) بود. میزان عصاره کلی و بازدهی اسید گلیسیریزیک به عنوان متغیرهای وابسته در نظر گرفته شدند. نتایج نشان داد که قطر ریشه شیرین بیان تاثیر معنی داری بر بازدهی اسید گلیسیریزیک داشت، در حالی که تاثیر معنی داری بر اندازه ذره مشاهده نشد. بر اساس نتایج مدلسازی فرایند استخراج، شرایط بهینه حداکثرسازی میزان عصاره کلی از ریشه شیرین بیان شامل اندازه ذره،  μm125≥ (mesh 120 ≤) و قطر ریشه شیرین بیان، 28/3 سانتی متر حاصل شد که منجر به استخراج عصاره کلی از ریشه شیرین بیان به میزان 16/68 درصد وزنی گردید. شرایط بهینه بازدهی اسید گلیسیریزیک از ریشه شیرین بیان شامل اندازه ذره، μm 125≥ (mesh 120 ≤) و قطر ریشه شیرین بیان، 72/2 سانتی متر بود که منجر به استخراج اسید گلیسیریزیک از ریشه شیرین بیان به میزان 02/6 درصد وزنی گردید. همچنین مقایسه بین استخراج اسید گلیسیریزیک از شیرین بیان در حمام التراسونیک و با پراب التراسونیک نشان داد که میزان استخراج اسید گلیسیریزیک توسط پراب التراسونیک و در حمام التراسونیک مشابه و برابر با 5/5 درصد وزنی بود. به طور کلی از نتایج این پژوهش می توان ادعا کرد که روش سطح پاسخ یک روش مطمین برای بهینه سازی شرایط فرایندی استخراج اسید گلیسیریزیک از ریشه شیرین بیان با استفاده از التراسونیک است.

    کلیدواژگان: شیرین بیان، التراسونیک، اسید گلیسیریزیک، روش سطح پاسخ
  • فریبا عطایی نوکابادی*، نرگس نهچیری، جواد کرامت، منوچهر مومنی شهرکی صفحات 195-202

    دراین مطالعه خمیر کیک اسفنجی به روش شکر- خمیر تهیه گردید و تاثیرجایگزینی آرد گندم در نسبت های صفر، 25، 50، 75 و100 درصد توسط آرد دانه ماش بر ویژگی های بافتی، فیزیکی، شیمیایی و حسی کیک اسفنجی طی دوره انباربانی 30 روزه در یک طرح کاملا تصادفی مورد ارزیابی قرار گرفت. نتایج نشان داد که سختی بافت در نمونه های 75 و 100 درصد افزایش وفنریت تنها در نمونه 100 درصد طی دوره انبارداری کاهش یافت، این در حالی است که تفاوت معنی داری در پیوستگی بافت نمونه ها دیده نشد. نیروی لازم جهت سوراخ کردن و برش بافت نیز در درصدهای بالای جایگزینی افزایش یافت همچنین میزان چربی، گلوتن و رطوبت با افزایش میزان پودر ماش کاهش و میزان پروتیین، خاکستر، دانسیته نمونه ها به طور معنی داری افزایش یافت (p≤0.05). نتایج حاصل از آزمون رنگ نشان داد که قرمزی تیمارها نسبت به نمونه شاهد (صفر درصد) افزایش اما روشنایی و زردی با اختلاف معنی داری کاهش یافته است. با توجه به آزمون حسی انجام گرفته شده (هدونیک 5 نقطه ای) ونتایج حاصل از آزمون بافت، می توان جایگزینی 25 درصد آرد گندم با آرد ماش را به عنوان بهترین جایگزینی عنوان کرد..

    کلیدواژگان: آرد ماش، کیک اسفنجی، سختی، فنریت، پیوستگی
  • الناز صفاری سامانی، حسین جوینده*، بهروز علیزاده بهبهانی صفحات 203-217
    هدف از این پژوهش شناسایی ترکیبات شیمیایی، گروه‏های عاملی زیست‏فعال، فعالیت آنتی اکسیدانی، فنل کل و فلاونویید کل اسانس آویشن شیرازی و همچنین بررسی اثر سمیت سلولی آن بر رده سلولی سرطان روده بزرگ (HT29) بود. ترکیبات شیمیایی اسانس آویشن شیرازی با استفاده از دستگاه کروماتوگرافی گازی متصل به طیف سنج جرمی شناسایی شد. گروه‏های عاملی زیست‏فعال اسانس آویشن شیرازی با استفاده از دستگاه FTIR در محدوده عدد موجیcm-1 500-4000 اندازه گیری شد. به منظور اندازه گیری میزان فنل کل و فلاونویید کل اسانس آویشن شیرازی به ترتیب از روش های فولین سیوکالتو و رنگ سنجی آلومینیوم کلراید استفاده گردید. از روش MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyltetrazolium bromide) جهت اندازه گیری سمیت سلولی اسانس آویشن شیرازی در برابر رده سلولی سرطان روده بزرگ (HT29) استفاده شد. قدرت آنتی کسیدانی اسانس آویشن شیرازی با استفاده از مهار رادیکال آزاد DPPH و ABTS بررسی گردید. ترکیب کارواکرول و تیمول به ترتیب با 3/39 و 30 درصد بیشترین ترکیب تشکیل دهنده اسانس آویشن شیرازی بودند. وجود پیک در عدد موجی cm -11000-320 نشان دهنده پیوندهای C-O است که می تواند مربوط به ترکیبات آلی همچون الکل ها، اسیدهای کربوکسیلیک، استرها و اتر باشد. میزان فنل کل و فلاونویید اسانس آویشن شیرازی به ترتیب 05/64 میلی گرم گالیک اسید بر گرم و 68/11 میلی گرم کویرستین بر گرم بود. میزان درصد مهارکنندگی رادیکال های آزاد با استفاده از DPPH و ABTS در غلظت ppm 1000 به ترتیب 69/63 و 33/64 بود. با افزایش غلظت اسانس آویشن شیرازی، تاثیر بر رده سلولی HT29 افزایش پیدا کرد و درصد زنده مانی آن کاهش یافت. با توجه به نتایج قدرت آنتی اکسیدانی، فنل و فلاونویید کل اسانس آویشن شیرازی به نظر می رسد بتوان از گیاه آویشن شیرازی به عنوان نگهدارنده طبیعی در صنایع غذایی بهره برد.
    کلیدواژگان: اسانس آویشن شیرازی، سمیت سلولی، فعالیت آنتی اکسیدانی، زنده مانی سلول های HT29
  • زینب ابرچائی، علیرضا رحمن*، مریم فهیم دانش صفحات 218-234

    در این تحقیق عصاره سماق با مقادیر 5/0، 1 و 5/1 درصد و فسفاتیدیل اتانول آمین با مقادیر 01/0، 04/0 و 08/0 درصد به عنوان نگهدارنده در سس مایونز مورد استفاده قرار گرفتند. پس از عصاره گیری و ارزیابی بازده استخراج سماق، فنول تام و میزان مهارکنندگی رادیکال های آزاد (DPPH) ارزیابی شد. آزمون های سس مایونز شامل شاخص پراکسید، شاخص توتوکس، شاخص اسیدیته و ارزیابی حسی در بازه های زمانی روز تولید (روز صفر)، ماه اول، ماه دوم و ماه سوم بررسی شدند. تحقیق در قالب طرح کامل تصادفی در سطح معنی داری 05/0 صورت پذیرفت و نتایج با آزمون مقایسه میانگین دو طرفه (ANOVA) و توسط نرم افزار آماری SPSS آنالیز گردید. نتایج نشان داد که با افزایش میزان استفاده از عصاره سماق و فسفاتیدیل اتانول آمین میزان شاخص پراکسید و شاخص توتوکس به طور معنی داری در مقایسه با تیمار شاهد کاهش داشت (05/0≥p). همچنین افزایش میزان استفاده از عصاره سماق در فرمولاسیون سس مایونز به طور معنی داری شاخص اسیدیته تیمارهای سس مایونز را افزایش داد (05/0≥p). در تیمارهایی دارای میزان بالاتر فسفاتیدیل اتانول آمین میزان افزایش اسیدیته تیمارهای سس مایونز در طی زمان نگهداری با شدت کمتری همراه بود (05/0≥p). در بررسی خصوصیات حسی نیز مشاهده شد که با افزایش میزان استفاده از عصاره سماق، میزان مطلبوبیت حسی تیمارها در روز تولید کمتر بود، استفاده از فسفاتیدیل اتانول آمین در مقادیر 08/0 به حفظ خصوصیات حسی بالاتری در مقایسه با تیمار شاهد منجر شد. افزایش میزان استفاده از عصاره سماق امتیازات بافت و رنگ ظاهری تیمارهای سس مایونز را به طور معنی داری کاهش داد (05/0≥p). زمان به طورکلی افزایش معنی داری در افزایش کلیه شاخص های سس مایونز نشان داد (05/0≥p). در نهایت تیمار 1 درصد عصاره سماق و همچنین 08/0 درصد فسفاتیدیل اتانول آمین به عنوان ترکیب بهینه انتخاب و معرفی گردید. با توجه به نتایج به دست آمده می توان سس مایونز حاوی عصاره سماق را به عنوان یک محصول طبیعی و سلامت بخش جدید به بازار معرفی نمود، زیرا گیاه سماق به علت دارا بودن ترکیب های فنولی، قدرت ضداکسندگی قوی و نیز خاصیت ضدمیکروبی می تواند به عنوان یکی از افزودنی های مطرح در صنعت غذا استفاده شود

    کلیدواژگان: سس مایونز، عصاره سماق، فسفاتیدیل اتانول آمین، خصوصیات شیمیایی
  • بهمن ساعدپناه، ناصر بهروزی خزاعی*، جلال خورشیدی صفحات 235-247

    توسعه روش های نوین برای استخراج اسانس از گیاهان دارویی روزبه روز در حال گسترش است. هدف از این پژوهش، پیاده سازی و ارزیابی سامانه استخراج اسانس به کمک مایکروویو می باشد. 13 آزمایش با سه سطح توان (300، 600 و 900 وات) و سه سطح زمان (5، 20 و 35 دقیقه) برای اندازه گیری بازده اسانس استخراجی در نظر گرفته شد. بازده اسانس استخراجی به کمک روش سطح پاسخ با طرح مرکب مرکزی (CCD) مدل سازی و بهینه سازی شد. همچنین نوع و میزان ترکیبات اسانس استخراجی در هر تیمار آزمایشی به کمک کروماتوگرافی گازی متصل به طیف سنج جرمی (GC- MS) و کروماتوگرافی گازی (GC) تعیین گردید. بازده و کیفیت اسانس استخراجی توسط کلونجر هم به عنوان تیمار شاهد در نظر گرفته شد. نتایج نشان داد که مدل درجه دو توانی قادر است بازده اسانس را با R2، R2Adj و R2Pre  به ترتیب با مقادیر 9590/0، 9459/0 و8864/0 پیش بینی کند. همچنین نتایج بهینه سازی نشان داد که توان 866 وات و زمان 34 دقیقه به عنوان شرایط بهینه کاری سامانه اسانس گیری به دست آمد که با این شرایط کاری بازده اسانس استخراجی به 37/0 درصد (حجمی/ وزنی) رسید. همچنین تجزیه و تحلیل اسانس ها نشان داد در تیمارهای مختلف تعداد و درصد ترکیبات غالب به دست آمده متفاوت هستند. در تیمار 900 وات، ترکیبات غالب اسانس کاریوفیلن و بورنیول بودند، در حالیکه در تیمارهای 300 و 600 وات و کلونجر ترکیبات غالب اسانس، آلفاپینن، کامفن و کامفور بودند.

    کلیدواژگان: اسانس گیری، زمان استخراج، روش سطح پاسخ، کلونجر، مایکروویو
  • نفیسه کریمی، رضوان پوراحمد*، سلمان طاهری، اورنگ عیوض زاده صفحات 249-263

    هدف از این پژوهش، بررسی اثر افزودن پپتید زیست فعال حاصل از هیدرولیز آنزیمی آب ماست بر ویژگی های کیفی دوغ بود. پپتید حاصل از هیدرولیز پروتیین آب ماست با تریپسین، که با استفاده از RP-HPLC تفکیک (جزء به جزء) شده بود، مورد استفاده قرار گرفت. غلظت های مختلف این پپتید (20/12، 4/24 و mg/mL 8/48) به دوغ اضافه گردید. به منظور بررسی اثر ضدمیکروبی این پپتید، تراکم CFU/mL 106 از باکتری های استافیلوکوکوس اوریوس و اشریشیا کلی به دوغ تلقیح شد. طی 60 روز نگهداری، شمارش باکتریایی (استافیلوکوکوس اوریوس و اشریشیا کلی)، pH، اسیدیته، مهار رادیکال کاتیون ABTS (2, 2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid)  و خواص حسی نمونه های دوغ ارزیابی گردید. نتایج نشان داد که طی دوره نگهداری، تعداد باکتری های استافیلوکوکوس اوریوس و اشریشیا کلی ، مقادیر pH و مهار رادیکال کاتیون ABTS در کلیه نمونه ها به طور معنی داری کاهش یافت (05/0>p)، ولی اسیدیته افزایش پیدا کرد. پپتید حاصل از آب ماست فعالیت های آنتی اکسیدانی و ضدباکتریایی خوبی در نمونه های دوغ نشان داد، به طوری که با افزایش سطح پپتید در نمونه ها، مهار رادیکال به طور معنی داری افزایش و شمارش باکتری های بیماری زا کاهش یافت (05/0>p). تیمار حاوی بالاترین سطح پپتید  mg/mL) 8/48) در روز بیستم انبارمانی، فاقد استافیلوکوکوس اوریوس و اشریشیا کلی بود. نتایج ارزیابی حسی نشان داد که در نمونه شاهد (فاقد پپتید زیست فعال) و نمونه حاوی پایین ترین سطح پپتید mg/mL) 20/12)، امتیاز ویژگی های حسی طی دوره نگهداری کاهش یافت، ولی استفاده از بالاترین سطح پپتید آب ماست در فرمولاسیون دوغ توانست سرعت افت ویژگی های حسی را طی دوره نگهداری کاهش داده و کیفیت محصول را حفظ نماید. بر طبق نتایج حاصله، غلظت  mg/mL 8/48 پپتید را می توان به عنوان بهترین سطح جهت غنی سازی دوغ انتخاب کرد. بنابراین پپتید حاصل از هیدرولیز آنزیمی آب ماست می تواند به عنوان عامل آنتی اکسیدانی و ضدمیکروبی طبیعی در محصولات لبنی مانند دوغ مورد استفاده قرار گیرد.

    کلیدواژگان: پپتید زیست فعال، دوغ، فعالیت آنتی اکسیدانی، اثر ضدباکتریایی، دوره نگهداری
  • حدیث چراغی، فردین قنبری*، مهدی صیدی صفحات 264-276

    قهوه ای شدن بافت یکی از مهم ترین دلایل کاهش کیفیت قارچ دکمه ای در دوره پس از برداشت است که تحت تاثیر آنزیم پلی فنل اکسیداز اتفاق می افتد. در این تحقیق امکان کاهش قهوه ای شدن قارچ خوراکی و حفظ کیفیت آن با کاربرد خارجی سینامیک اسید، به عنوان بازدارنده فعالیت آنزیم پلی فنل اکسیداز، مورد بررسی قرار گرفت. تیمار سینامیک اسید در چهار سطح (شاهد، 100، 200 و 400 میکرومولار) اعمال شد و پس از آن قارچ ها به مدت 16 روز در دمای 4 درجه سانتی گراد قرار گرفتند. نتایج نشان داد که با افزایش زمان نگهداری فعالیت آنزیم پلی فنل اکسیداز و پراکسیداز افزایش یافت و به تبع آن قهوه ای شدن بافت نیز روند افزایشی داشت. همچنین با افزایش زمان نگهداری درصد کاهش وزن، پراکسید هیدروژن و مالون دی آلدهید افزایش یافت و فنل کل و ظرفیت آنتی اکسیدانی کل روند کاهشی داشت. استفاده از تیمار سینامیک اسید در هر سه غلظت (100، 200 و 400 میکرومولار) سبب کاهش فعالیت آنزیم های پراکسیداز و پلی فنل اکسیداز شد و قهوه ای شدن بافت را کاهش داد. همچنین کاربرد سینامیک اسید سبب بهبود صفات کیفی قارچ خوراکی مانند فنل کل، ظرفیت آنتی اکسیدانی کل و شاخص کیفیت ظاهری شد. به طور کلی نتایج این تحقیق نشان داد که استفاده از سینامیک اسید، خصوصا در غلظت 400 میکرومولار، سبب کاهش قهوه ای شدن بافت، حفظ کیفیت و کاهش افت وزن قارچ خوراکی در دوره پس از برداشت می شود

    کلیدواژگان: پلی فنل اکسیداز، ظرفیت آنتی اکسیدانی، فنل کل، قهوه ای شدن بافت، کاهش وزن
  • مرتضی محمدی*، محمد قربانی، علیرضا صادقی ماهونک، عادل بیگ بابایی، سمیرا یگانه زاد صفحات 277-293

    ترکیبات فنولی به دلیل پتانسیل آنتی اکسیدانی و اثرات سلامتی بخش بر سلامتی انسان به عنوان غذا های فراویژه شناخته شده اند. در این پژوهش ترکیبات فنولی با استفاده از سیال مادون بحرانی آب، از پوست پسته استخراج و پتانسیل آنتی اکسیدانی آن ها مورد بررسی قرار گرفت. فرآیند استخراج در دمای 120 تا 180 درجه سانتی گراد، تحت فشار های 10 تا 50 بار و نسبت اختلاط حلال 1:10 تا 1:30 (حلال به نمونه)، با استفاده از سیال مادون بحرانی آب انجام شد. مقدار ترکیبات فنولی کل، قدرت احیاکنندگی، قدرت رادیکال گیرندگی و قدرت پایدارکنندگی در روغن سویا برای عصار های استخراجی اندازه گیری شد. قدرت پایدارکنندگی عصاره ها در روغن سویا و با استفاده از آزمون اندازه گیری پایداری حرارتی، در دمای 110 درجه سانتی گراد و جریان هوای 20 لیتر بر ساعت صورت گرفت. مقایسه و تجزیه و تحلیل آماری نتایج با استفاده از روش سطح پاسخ انجام گردید. نتایج نشان داد که مقدار ترکیبات فنولی از 43/7671 تا 57/8903 میلی گرم گالیک اسید در صد گرم نمونه در تغییر بود. قدرت احیاکنندگی از دمای 120 تا 150 درجه سانتی گراد افزایش یافت و اثر فشار بر ترکیبات فنولی عصاره ها قابل توجه نبود. بهترین نتیجه در شرایط دمایی143 درجه سانتی گراد، فشار 10 بار و نسبت اختلاط 1:12 به دست آمد. قدرت احیاکنندگی آهن، قدرت پایدارکنندگی و جذب رادیکال های آزاد عصاره های استخراجی از پوست پسته مشابهت زیادی با آنتی اکسیدان سنتزی BHT داشت. نتایج حاکی از آن بود که کاربرد آب مادون بحرانی در استخراج ترکیبات موثره از پوست پسته تاثیر معنی داری در افزایش راندمان استخراج داشت و عصاره های استخراجی در مقایسه با روش سنتی از ویژگی های آنتی اکسیدانی بالاتری برخوردار بودند

    کلیدواژگان: آب مادون بحرانی، پوست پسته، روش های نوین استخراج، ضایعات کشاورزی، ترکیبات فلاونوئیدی، پایدارسازی روغن خوراکی
  • سارا فروزنده، محمد فاضل* صفحات 295-305

    در این پژوهش راندمان استخراج، ترکیب و میزان اسیدهای چرب موجود در روغن دانه چیا و فعالیت آنتی اکسیدانی آن مورد بررسی قرار گرفت. همچنین نانوامولسیون های 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 آنتی اکسیدانی مورد ارزیابی قرار گرفت. همچنین میزان رهایش نانوامولسیون ها 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 09/47% لینولنیک اسید بود و میزان خاصیت آنتی اکسیدانی آن به طور میانگین (43/88%) اندازه گیری شد. نتایج آزمون های انجام شده بر روی نانوامولسیون ها نشان داد که که با افزایش میزان روغن نانوامولسیون ها، اندازه ذرات و خاصیت آنتی اکسیدانی و رهایش افزایش یافته و راندمان درون پوشانی کاهش می یابد. همچنین با افزایش نسبت امولسیفایر به روغن در نانوامولسیون ها راندمان درون پوشانی و خاصیت آنتی اکسیدانی افزایش یافته و اندازه ذرات و رهایش کم می شود. در نتایج به دست آمده از این آزمون ها کمترین اندازه ذرات 08/14 نانومتر بود و بیشترین راندمان درون پوشانی 40/96% به دست آمد. فعالیت آنتی اکسیدانی نمونه ها در محدوده 61/5% تا 43/21% ارزیابی شد. همچنین میانگین رهایش نمونه ها در پایان 7 هفته بررسی به نزدیک 18 درصد رسید. در طی نگهداری تیمارها به مدت پنج ماه، کاملا پایدار بودند.

    کلیدواژگان: نانوامولسیون، روغن دانه چیا، امولسیفایر، فعالیت آنتی اکسیدانی
  • زهرا شیخ الاسلامی*، مهدی کریمی، بهاره صحرائیان صفحات 307-329

    هدف از این پژوهش جایگزینی آرد گندم (صفر، 15 و 30 درصد) با آرد تریتیکاله در دونات بود که به منظور بهبود ویژگی‏های دونات از صمغ ریحان (صفر، 50/0 و 1  درصد) و اسانس هل سبز (50، 100، 150 و 200 پی پی ام) استفاده شد. نتایج نشان داد، نمونه حاوی 15 درصد آرد تریتیکاله و 50/0 درصد صمغ دارای بیشترین حجم مخصوص (4/3 سانتی‏مترمکعب بر گرم) و نسبت شاخص تخلخل (81/0) و کمترین سفتی بافت پس از یک هفته نگهداری (91/11 نیوتن) بود و به عنوان بهترین نمونه معرفی شد. همچنین نتایج حاکی از کاهش 83/29 درصدی محتوی روغن بهترین نمونه در مقایسه با شاهد بود. رطوبت نمونه ذکر شده یک هفته پس از تولید 09/21 درصد و میزان مولفه رنگی L*، a* و b* آن به ترتیب 27/55، 86/8 و 91/11 بود. نتایج فاز دو نشان داد، اسانس هل سبز در تمامی غلظت‏ها دارای فعالیت آنتی‏اکسیدانی بودند. نتایج شمارش کپک و مخمر نیز حاکی از آن بود میزان رشد کپک و مخمر نمونه‏های حاوی100، 150 و 200 پی پی ام اسانس هل طی 15 روز نگهداری در مقایسه با نمونه فاقد اسانس به ترتیب 05/51، 03/53 و 75/63 درصد کمتر بود. بهترین نمونه به لحاظ فعالیت آنتی‏اکسیدانی و کاهش رشد کپک و مخمر نمونه حاوی 15 درصد آرد تریتیکاله، 50/0 درصد صمغ و 200 پی پی ام اسانس بود. اما نمونه حاوی 15 درصد آرد تریتیکاله، 50/0 درصد صمغ و 100 پی پی ام اسانس از بیشترین امتیاز پذیرش کلی، کمترین میزان محتوی روغن و سفتی بافت، بیشترین حجم و تخلخل برخوردار بود.

    کلیدواژگان: دونات، محتوی روغن، صمغ ریحان، آرد تریتیکاله، فعالیت آنتی‏اکسیدانی
  • سید امیر توکلی لاهیجانی، فخری شهیدی*، محمود حبیبیان، آرش کوچکی صفحات 330-342

    نظر به اهمیت نقش گلوتن در محصولات غله‏ای به ویژه نان و ضرورت اصلاح آرد، ارایه یک روش ساده، اقتصادی و کارا به منظور بهبود کیفیت تکنولوژیکی گندم و نان تولیدی، همچنان یک چالش مهم و بحث برانگیز می باشد. در این پژوهش تاثیر تکنولوژی نوین پلاسمای غیرحرارتی بر بهبود ویژگی‏های فیزیکو شیمیایی و عملکردی آرد گندم بررسی شد. بدین منظور آرد گندم با گلوتن متوسط تهیه و تحت تاثیر زمان اعمال تیمار پلاسمای سرد (زمان صفر، 2، 4، 6، 8 و 10 دقیقه) قرار گرفتند. نتایج آزمون‏های فیزیکوشیمیایی نشان داد که با افزایش زمان اعمال تیمار پلاسما، مقدار pH و رطوبت کاهش اما مقدار گلوتن مرطوب، اندیس گلوتن و حجم رسوب زلنی افزایش یافت، اندازه‏گیری پارامترهای کیفی و عملکردی آرد گندم نشان داد پارامتر L*، درصد نشاسته آسیب‏دیده، اندیس حلالیت، ظرفیت جذب آب و روغن و قدرت تورم آرد گندم افزایش معنی‏داری (05/0>P) یافت، در حالی که پارامترهای a*، b* و عدد فالینگ کاهش معنی‏داری (05/0>P) پیدا کرد. بنابراین می توان از تکنولوژی نوین پلاسمای سرد به ویژه زمان 8 دقیقه در بهبود ویژگی‏های کیفی و عملکردی آرد گندم استفاده نمود.

    کلیدواژگان: آرد، اصلاح، پلاسمای غیر حرارتی، گلوتن، گندم
  • ساناز فلاح تفتی زاده*، غلامرضا عبدی، فاطمه زنده بودی، مهدی محمدی صفحات 343-365

    اکسیداسیون چربی ها باعث تغییر در صفات کیفی روغن های گیاهی از جمله روغن زیتون بکر می شوند. آنتی اکسیدان های مصنوعی برای حفظ روغن استفاده شده اند. با این حال، علاقه به جایگزینی آن ها با مواد طبیعی وجود دارد. جلبک اسپیرولینا پلاتنسیس (Spirulina platensis) و گیاه گازرخ (Moringa Oleifera) به دلیل فعالیت های آنتی اکسیدانی آن ها شناخته شده اند. این مطالعه به منظور تعیین پایداری اکسیداسیون روغن زیتون بکر حاوی عصاره جلبک اسپیرولینا و گیاه گازرخ صورت گرفت. بدین منظور، عصاره اتانولی اسپیرولینا و گازرخ تهیه گردید. میزان ppm 1000 از هر یک از عصاره ها به صورت جداگانه و ppm 1000به صورت ترکیب آن ها (با نسبت مساوی) به 100 گرم روغن زیتون بکر اضافه شد و یک نمونه حاوی آنتی اکسیدان مصنوعی TBHQ (Tert-Butylhydroquinone) و یک نمونه روغن زیتون بکر به عنوان شاهد در نظر گرفته شد. ترکیبات پلی فنولیک عصاره ها توسط HPLC شناسایی شدند. اندیس پراکسید، ضریب شکست و ارزیابی رنگ (L*، a*، b*) نمونه های روغن زیتون بکر اندازه گیری شد. نتایج نشان داد که ترکیبات موثره در عصاره های اسپیرولینا پلاتنسیس و گیاه گازرخ، ترکیبات پلی فنولی رزمارینیک اسید، کاتچین، کویرستین، وانیلین، هسپریدین، هسپرتین است. شاخص پراکسید روغن زیتون در 3 تیمار حاوی عصاره های طبیعی کاهش معنی داری نسبت به نمونه شاهد و نمونه حاوی TBHQ داشت (05/0< p). وجود عصاره های طبیعی در روغن زیتون بکر باعث کاهش ویژگی های رنگی (L*، a*، b*) شد ولی با نمونه شاهد اختلاف معنی داری نداشت (05/0> p). با توجه به نتایج شاخص پراکسید نمونه های حاوی عصاره می توان بیان کرد که با شناخت اثرات آنتی اکسیدانی عصاره اسپیرولینا پلاتنسیس و گیاه گازرخ می توان از آن ها برای استفاده صنعتی و جایگزینی با آنتی اکسیدان های مصنوعی بهره برد.

    کلیدواژگان: روغن زیتون بکر، اسپیرولینا پلاتنسیس، گیاه گازرخ، هم افزایی، هم ستیزی، آنتی اکسیدان
  • صدیقه یزدان پناه*، سارا محمدی، امیرحسین الهامی راد صفحات 367-382

    چای سفید در بین انواع چای، به عنوان یک ترکیب جدید، حاوی دامنه وسیعی از ترکیبات فنلی، آنتی اکسیدانی و ضدمیکروبی است. در این مطالعه ابتدا عصاره آبی چای سفید استخراج شد و روغن کنجد با استفاده از پرس سرد تولید گردید. در مرحله بعد، شش نمونه شامل نمونه روغن کنجد (نمونه شاهد)، روغن کنجد حاوی عصاره چای سفید، روغن کنجد حاوی عصاره چای سفید و 1/0 پی پی ام آهن، روغن کنجد حاوی عصاره چای سفید و 1/0 پی پی ام مس، روغن کنجد حاوی عصاره چای سفید و 1/0 پی پی ام روی و روغن کنجد حاوی 100 پی پی ام BHT تهیه شد. بررسی فنل کل و قدرت احیاکنندگی بر روی عصاره چای سفید و قدرت آنتی اکسیدانی، عدد پراکسید، پایداری اکسایشی و پروفایل اسیدهای چرب بر نمونه های حاوی روغن کنجد انجام شد. نتایج نشان داد که عصاره آبی چای سفید دارای 06/4 (میلی گرم گالیک اسید بر گرم نمونه) فنل کل است. قدرت احیاکنندگی آنتی اکسیدان BHT 40 برابر عصاره آبی چای سفید و قدرت آنتی اکسیدان BHT 85/14 برابر، عصاره آبی چای سفید بود. در مهار رادیکال های آزاد در روغن کنجد، عصاره آبی چای سفید نسبت به نمونه شاهد به صورت معنی داری تاثیر بیشتری داشته است. عصاره چای سفید و روغن کنجد به دلیل داشتن ترکیبات آنتی اکسیدانی و فنلی قادر به مهار رادیکال های آزاد و پراکسیدان های فلزی به خصوص دو فلز مس و روی بوده اند. تاثیر پراکسیدان های فلزی بر پروفایل اسیدهای چرب با استفاده از شاخص (Se) پلی-ان (اسیدهای چرب چند غیراشباع/ اسیدهای چرب اشباع) که معیاری از میزان غیراشباعیت است، مورد بررسی قرار گرفت. نمونه های حاوی پراکسیدان های فلزی شاخصپلی-ان پایین تری نسبت به سایر نمونه ها نشان دادند و نمونه روغن کنجد به همراه آهن نسبت به سایر نمونه ها، اکسیداسیون بیشتر، پایداری اکسایشی کمتر و کاهش بیشتر اسید لینولنیک را داشته است. اسیدهای چرب غالب روغن کنجد شامل پالمیتیک اسید، استیاریک اسید، اولییک اسید، لینولییک اسید و لینولنیک اسید بود. نتایج پایداری حرارتی نشان داد که بالاترین پایداری مربوط به دو نمونه روغن کنجد به همراه BHT (61/9 ساعت) و روغن کنجد به همراه عصاره چای (42/9 ساعت) و پایین ترین پایداری حرارتی در نمونه روغن کنجد به همراه آهن (81/4 ساعت) بوده است. نتایج شاخص پلی-ان تاییدی بر نتایج رنسیمت بود. روغن کنجد استخراج شده به وسیله پرس سرد به دلیل مقاومت حرارتی پایین، مصرف سرخ کردنی ندارد ولی برای استفاده در فرمولاسیون سس های سالاد می تواند کاربرد داشته باشد.

    کلیدواژگان: آنتی اکسیدان، پایداری اکسیداتیو، روغن کنجد، کاتالیزور فلزی
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  • Zarrin Nasri * Pages 179-194
    Introduction

    Licorice is one of the most important medicinal plants in the world. This plant has been used in the world for more than 2000 years and is applied in various industries including pharmaceutical, food and tobacco industries. Iran is one of the best regions in the world in terms of medicinal plants. The roots of the licorice plant are widely used in the food and pharmaceutical industries. These roots are strong natural sweeteners, about 50-170 times sweeter than sucrose. The value of this plant is related to its chemical components. Glycyrrhizin is the most abundant component of this plant and is present in licorice in the form of potassium or calcium salt of glycyrrhizic acid and is considered as an indicator of licorice quality. In recent years, novel extraction methods with different energy sources have been proposed for improving extraction efficiency. Higher extraction efficiencies can be achieved by using microwave, ultrasonic and high pressure methods. In the ultrasonic extraction method, the extraction rate increases due to the presence of cavitation. The cavities formed in the solvent grow and then collapse rapidly, releasing a large amount of energy that increases the local temperature and pressure. Therefore, the solvent penetrates more into the plant cell material and the contents of the plant cells are released into the solvent medium. Also, physical effects such as liquid circulation and turbulence produced by cavitation help to increase the contact surface between the solvent and the plant particles and lead to more solvent penetration into the plant matrix.

    Materials and Methods

    The aim of this study is to statistically investigate the effect of particle size and licorice root diameter on the rate of glycyrrhizic acid extraction using ultrasonic. The full factorial experimental design method and response surface methodology have been used to determine the levels of the parameters and to model the responses, respectively. Independent variables included particle size of licorice root at three levels (35-60, 60-120, ≥ 120 mesh) and licorice root diameter is at three levels (1-2, 2-3, ≥3 cm). Total extract and glycyrrhizinic acid yield are considered as response variables. The solvent used was ammonia and the analysis of glycyrrhizic acid in the extract was performed by HPLC method. The licorice root used in this research was from Bojnourd region. Monoammonium glycyrrhizic acid (99.5%) was purchased as an HPLC standard from Sigma and ammonia from Merck. The method of glycyrrhizic acid extraction from licorice root was based on the British Pharmacopoeia method in this research.

    Result and Discussion

    The results showed that regarding the response glycyrrhizic acid yield, the parameter licorice root diameter had a significant effect on the response, but the particle size parameter had no significant effect. Also, two parameters had interaction. Based on the modeling results of the extraction process, the optimal conditions for obtaining the maximum total extract of licorice root included particle size, 125 μm (120 mesh) and licorice root diameter, 3.28 cm, which leaded to 68.16 wt% total extract. The optimal response conditions for glycyrrhizic acid yield from licorice root included particle size, (120 mesh) and licorice root diameter, 2.72 cm, which leaded to the extraction of 6.02 wt%glycyrrhizic acid from the root. Also, a comparison was performed between glycyrrhizic acid extraction from licorice in ultrasonic bath and ultrasonic probe. The results showed that the amount of glycyrrhizic acid extraction was similar and was equal to 5.5 wt%. The effect of particle size distribution has also been investigated. According to the results in ultrasonic extraction, particle size distribution had a positive effect on extraction.According to the results of this research, the parameter of licorice root diameter had a significant effect on the response of glycyrrhizic acid yield and with decreasing licorice root diameter, the amount of glycyrrhizic acid extraction increased. Also, the efficiency obtained by extraction method in ultrasonic bath is compared with ultrasonic probe. It can be concluded that glycyrrhizic acid extraction from licorice with using ultrasonic is an effective method for extraction

    Keywords: Licorice, Ultrasonic, Glycyrrhizic acid, Response surface methodology
  • Fariba Ataei Nukabadi *, Narges Nehchiri, Javad Keramat, Manuchehr Momeni Shahraki Pages 195-202
    Introduction

    Increasing demand for various quality food products with health-related properties has caused many efforts to be made in producing such products. Cereal industry is among major industries with the potential of attracting people’s attention in this regard. However, staling and lack of fiber and other nutritients in flour is a problem with the products of this industry. Mung bean belongs to Fabaceae family. Mung bean has 7.91% water content, 24.08% protein content, 1.55% fat content, 2.87% ash content, 2.20% fiber content, and 25.73% starch content. In addition, Mung bean has bioactive compounds like tannin, phytic acid, flavonoid, phenolic acid, and other organic acids. This bean is cultivated in Asia, Australia, New Zealand, and Africa.

    Materials and Methods

    In this study, mung bean powder was used in the formulation of sponge cake. The ingredients used in the formula were flour, cake liquid oil, sugar, fresh eggs, dry milk powder, baking powder, whey protein, vanilla and water. Mung bean flour replacied wheat flour by 0, 25, 50, 75, 100% in the sponge cake formula. The traditional sponge cake formula in this study was adopted from the work of Ataei Nukabadi and Hojjatoleslamy (2017). Sugar and oil were mixed for 5 min; the eggs were then added and mixed on the speed 3 setting for 5 min. The sifted powder materials and mung powder were gradually added into the mixer on speed 3 setting for 5 min. For each cake, 58- 60 g of cake batter was poured into a cake pan (50 g) and baked at 250- 280°C for 20 min in preheated oven. The cakes were allowed to cool for 1 hour and then the cooled cakes were packed in poly propylene bags at room temperature before performing physicochemical and sensory evaluation. Chemical evaluation including moisture content, crude protein, ash, crud fat, density, wet gluten, were measured on the sponge cakes according to their standards. Texture profile analysis (TPA) of the cake samples from the midsection of the cakes was carried out using a texture analyzer on the first and thirtieth day of storage and Hardness, cohesiveness, cut, punch and springeness were also measured. Hunter Lab and a*, b*, L*, ∆E was used for color measurements of samples. The hedonic scale is a unique scale providing both reliable and valid results for sensory evaluation. A 5 point hedonic scale was applied to determine the degree of overall acceptance of the sponge cakes. Twenty semi- trained panelists received five samples and were asked to rate the samples based on degree of preference on a five- point hedonic scale (one: extremely dislike, two: dislike, three: neither like nor dislike, four: like, five: extremely like). The panelists received samples from the midsection of the cakes which had been held at room temperature. Each measurement was an average value of 3 replicates. The experimental data were subjected to an analysis of variance (ANOVA) for a completely random design using a statistical analysis system. Duncan's multiple range test was used to determine the differences among means at significance level of 0.05.

    Result and Discussion

    The results showed that hardness, punch, density, ash and protein increased as the level of mung bean powder increased, whereas springiness, moisture content, fat and gluten decreased. There was no significant difference between the samples in measuring the cohesiveness in the first and thirtieth day. Color measurements showed that crumb a* increased and b*, L*reverse trend was observed. The value of ∆E shown sponge cake contained 25% mung had the least difference with the control sample. In sensory evaluation, 25% sample was selected as an acceptable cake formula by the panelists, based on texture, taste, odor and color. The results shown, it is possible to produce sponge cake with different percentages of replacing wheat flour by mung bean powder. Increasing mung powder up to 50% does not have any significant effect on texture and organoleptic properties.

    Keywords: Mung flour, Sponge cakes, Hardness, Springiness, Cohesiveness
  • Elnaz Saffari Samani, Hossein Jooyandeh *, Behrooz Alizadeh Behbahani Pages 203-217
    Introduction
    Shirazi thyme is a perennial herbaceous plant related to Lamiaceae family growing in central and southern regions of Iran. This study aimed to assess chemical composition, bioactive functional groups, antioxidant potential, total phenol, and total flavonoids of Shirazi thyme essential oil (STEO) and also to evaluate its cell toxicity effect against the colorectal cancer cell line (HT29).
     
    Materials and Methods
    The chemical composition of STEO was identified by gas chromatography-mass spectrometry. The bioactive functional groups of STEO were measured by Fourier transform infrared at spectra range of 500- 4000 cm-1. The total phenol and total flavonoids of STEO were determined by folin- ciocalteu and aluminum chloride colorimetric method, respectively. MMT method was performed to measure the cell toxicity of STEO against the colorectal cancer cell line (HT29). The cells were cultured on DMEM high glucose medium supplemented with 10% fetal bovine serum and penicillin/streptomycin and incubated at 37°C with 95% relative humidity and 5% CO2 concentration. The antioxidant activity of STEO was evaluated by DPPH and ABTS free radicals scavenging assays. Duncan test at 5% probability and SPSS software (version 18) was performed to compare the means of obtained results.
     
    Results and Discussion
    Based on GC/MS spectrometry, a total of 29 constituents were identified and quantified in the STEO representing more than 99% of total constituents. Thymol with 39.3% and Carvacrol with 30% were the most constituents of STEO. The other major compound of STEO were Benzene (8.52%), γ-Terpinene (5.27%), and Caryophyllene (2.97%). The presence of peak at a wavelength of 320- 1000 cm-1 demonstrates O-C bound that could be related to organic compounds such as alcohols, carboxylic acids, esters, and ethers. The peaks occurred at spectral range between 2800- 3000 cm-1 (particularly at 2869.6 up to 2960.8 cm-1) are related to the stretching mode of C-H bounds and are mostly associated with alcoholic compounds in the essence. The amount of total phenol and flavonoids of STEO were 64.05 mg gallic acid equivalent/g and 11.68 mg quercetin equivalent/g, respectively. Results obtained from antioxidant activity of STEO with DPPH and ABTS free radicals scavenging showed that by increasing of STEO, the inhibition level of free radicals was enhanced. The inhibition percent of free radicals by using DPPH and ABTS at 1000 ppm concentration were 63.69% and 64.33%, respectively. The cell toxicity results of different STEO concentrations against the cell line HT29 revealed that survival of HT29 cells at 1, 3.125, 6.25, 12.5, 25, 50, 100 and 200 ppm of STEO were 100, 70.15, 61.19, 59.33, 38.83, 25.68, 20.65 and 12.2%. According to the results of this study, as the concentration of STEO increased, its effect on the cell line HT29 enhanced and the cell percentage viability decreased. Some antioxidant activity of STEO could be interrelated to its phenolic compounds. Based on the results of antioxidant activity, the amount of total phenol and flavonoids and the effect of STEO on cell toxicity against the cell line HT29, it seems that the use of STEO is applicable in the pharmaceutical and food industries
    Keywords: Shirazi thyme essential oil, Cell toxicity, Antioxidant activity, HT29 cell viability
  • Zeynab Abarchai, Alireza Rahman *, Maryam Fahim Danesh Pages 218-234

    Introduction:

     Sumac, due to its phenolic compounds, strong anti-oxidant strength and anti-coagulation, can be considered as one of the most popular additives in the food industry. The aim of this study was to investigate the synergistic effect of sumac and phosphatidylethanolamine on the chemical properties of mayonnaise.

    Materials and Methods

    In this research Sumac extract with 0.5,1 and 1.5 % and phosphatidyl ethanol amine with 0.01, 0.04 and 0.08 were used as native preservative. After extraction of sumac and evaluation of sumac extraction yield, total phenol and free radical inhibition test (DPPH) and Sensory evaluation were performed. Mayonnaise sauce analysis including peroxide index, Totox index, and acidity index were determined in production day, 1st, 2nd and 3rd month. The analysis was done by using completely randomized blocks design in 0.05 level and data were analyzed by two way Analysis variance (ANOVA) and SPSS software.

    Results and Discussion

    The results showed that with increasing the use of sumac extract and phosphatidylethanolamine extract, the peroxide and Tutox indices decreased significantly compared to the control (p≥0.05) Also, increasing the level of sumac extract in mayonnaise formulation, significantly increased the acidity index of mayonnaise treatments (p≥0.05). In treatments with higher levels of phosphatidylethanolamine, the increase in acidity of mayonnaise treatments was associated with less intensity during storage (p≥0.05). In the study of sensory properties, it was observed that with increasing the level of sumac extract, the amount of sensory content of the treatments was less on the day of production. Increasing the use of sumac extract the texture and color scores of mayonnaise treatments were significantly decreased (p≥0.05). In general, storage time showed a significant increase in the increasing of all mayonnaise indices (p≥0.05). Finally, the treatment of 1% sumac extract and 0.08% phosphatidyl ethanolamine was selected as the optimal combination. According to the obtained results, mayonnaise containing sumac extract can be introduced to the market as a natural and new functional product, because sumac plant has phenolic compounds, strong antioxidant power and antimicrobial properties. It can be used as one of the additives in the food industry

    Keywords: Mayonnaise sauce, Sumac extract, Phosphatidyl ethanol amine, Chemical properties
  • Bahman Saedpanah, Nasser Behroozi-Khazaei *, Jalal Khorshidi Pages 235-247
    Introduction

    Microwave-assisted extraction (MAE) is one of the newest techniques for extracting essential oils from medicinal plants. Microwave waves penetrate into plant cells and affect the polar molecules, causing heat to build up inside the plant tissue, destroying the cells and releasing the active ingredients. Although in terms of essential oil extraction efficiency, MAE method is slightly higher than Clevenger, but in terms of energy consumption, process time and amount of solvent consumed has an inherent advantage over the Clevenger method. In this study, the aim is to evaluate the quantity and quality of rosemary essential oil in the developed microwave extraction system and process optimization in this system. 

    Materials and Methods

    Rosemary plant (Rosmarinus officinalis L.) with 200 g used for each experiment. In this study, a microwave-assisted essential oil extraction system was developed. The system consisted of a home microwave, a distillation condenser, a cold-water source and a pump. In this study, the response surface methodology (RSM) used in the form of a central composite design with 13 treatments. The effect of two independent variables including power in the range of 300 to 900 watts and time in the range of 5 to 35 minutes on the efficiency of essential oil as dependent variables was investigated. To evaluate the quality of the extracted essential oil and compare it with Clevenger treatment, GC-Mass analysis was done using an Agilent technology apparatus (Agilent 7990B, USA).

    Results and Discussion

    A quadratic model was proposed for modelling of extraction efficiency and it was able to model with the values of R2, Adj R2 and Pred R2, which were 0.9521, 0.9180 and 0.574, respectively. The "Pred R2" of 0.547 is not as close to the "Adj R2" of 0.9180 as one might normally expect. The difference is more than 0.2. This may indicate a large block effect or a possible problem with the proposed model and/or data. Things to be considered for model modification are model reduction and response transformation. Results of ANOVA showed that only the linear terms of time, power and quadratic power of time are significant. The normal probability plot showed the normal distribution of errors observed in the experimental design space. The actual measured values R2 of the extracting efficiency from the experiments versus the values R2 predicted by the model indicated that this model could estimate the extracting efficiency with a correlation coefficient of 0.746. Box-Cox plot demonstrated for obtaining better results, the data of the amount of essential oil efficiency should be transferred to the power of 0.68 by the power function and the new model should be fitted to the data. Therefore, based on the Box-Cox diagram and the transfer of response data to the power space, as well as the use of a step-by-step method to remove meaningless terms from the model, the proposed model is as shown in equation 6. The results of the new model shows that the Pred R2 increased from 0.5574 to 0.8644, which indicates an   improvement in the performance of the new model. Alpha-pinene, camphene, borneol, camphor, cineole, and caryophyllene were the predominant compounds of the essential oil. In 300 and 600-watt treatments with a time of 35 minutes, the amount ofdominant compounds of essential oil is slightly higher than Clevenger. However, in the power of 900 watts, due to the increase in temperature, some compounds have been destroyed and the extraction level of some compounds has decreased drastically, and in contrast, the level of caryophyllene was increased to 23.595 %, which indicates a sharp increase in its value at 900 watts. On the other hand, the components of alphapenine, camphor and cineole have the highest medicinal value, which according to Table 8, the highest values for these compounds have been extracted in 300 watt treatment. At the higher microwave power, due to the decomposition of the compounds, the amount of extraction of these compounds was significantly reduced. Also, at 300 watts, the extraction efficiency of these compounds was higher than that of Clevenger, which shows the ability of the MAE method in extracting essential oils from medicinal plants.The results showed that the amount and quality of essential oil in the MAE with power of 300 and 600 watts was almost the same as Clevenger in most compounds. Essential oil compounds are degraded at 900 watts, so it is recommended not to use maximum power in the experiments. However, if the goal is to extract the highest amount of cariophylene, verbenone and cariophylene oxide in the extracted essential oil, higher power can be used.

    Keywords: : Essential oil, extraction Time, Response surface method, Microwave, Rosemary
  • Nafiseh Karimi, Rezvan Pourahmad *, Salman Taheri, Orang Eyvazzadeh Pages 249-263
    Introduction

    Yogurt contains valuable compounds, some of which enter yogurt whey and if discarded, remains unused. Yogurt whey has a high nutritional value due to its high quality biological proteins which can be a good source of bioactive peptides. Bioactive peptides are food-derived peptides that are small in size and usually consist of 3- 20 amino acids. These peptides are considered as functional ingredients. Bioactive  peptides have antioxidants and antimicrobial properties. The aim of this study was to investigate the effect of adding bioactive peptide derived from enzymatic hydrolysis of yogurt whey on physicochemical, sensory and microbial properties of doogh during storage.

    Materials and Methods

    In this study, peptide derived from tryptic hydrolysis of yogurt whey protein fractionated by RP- HPLC was used. Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of this peptide were determined against Staphylococcus aureus and Escherichia coli. This peptide was incorporated to heated doogh at concentrations of 12, 20, 24, 40, 48, and 80 mg/mL. Moreover, doogh samples were inoculated with 106 CFU/mL Staphylococcus aureus and Escherichia coli. Doogh samples were stored for two months. During 60 days storage, bacterial count, pH, acidity, ABTS radical cation inhibitory activity and sensory properties (taste, odor, texture, color and overall acceptance) of doogh samples were studied.

    Results and Discussion

    The MIC of yogurt whey peptide against Staphylococcus aureus and Escherichia coli was 12.2 and 24.4 mg/mL, respectively. Moreover, the MBC of yogurt whey peptide against Staphylococcus aureus and Escherichia coli was 12.2 and 48.8 mg/mL, respectively. Addition of this peptide to doogh showed that during storage period, the Staphylococcus aureus and Escherichia coli counts, pH and ABTS cation radical inhibitory activity of the samples were significantly decreased, but acidity was increased (p<0.05). The peptide of yogurt whey showed good antioxidant and antibacterial activities in doogh samples. By increasing the level of peptide in samples, the ABTS cation radical inhibitory activity was significantly increased (p<0.05).  During storage, the control sample (without bioactive peptide) showed the highest reduction in antioxidant activity and the lowest reduction was related to the sample containing 48.8 mg/mL bioactive peptide. The ABTS cation radical inhibitory activity of the control sample and sample containing 48.8 mg/mL bioactive peptide was 9.72 and 3.66 Unit/mL, respectively on the 60th day. By increasing the levels of bioactive peptide, pathogenic bacteria counts were decreased (p<0.05). The sample containing the highest level of peptide (48.8 mg/mL) was free of Staphylococcus aureus and E. coli on the 20th day of storage. The control sample and samples containing 12.2 and 24.4 mg/mL bioactive peptide were free of these pathogenic bacteria on the 60th and 40th days,  respectively. The highest rate of acidity and pH changes was related to the control sample and sample containing 48.8 mg/mL bioactive peptide had the lowest changes during storage. The acidity of control sample and sample containing 48.8 mg/mL bioactive peptide was 0.68 and 0.56% lactic acid, respectively on the 60th day.The results of sensory evaluation showed that in the control sample and sample containing the lowest level of peptide (12.2 mg/mL), the score of sensory characteristics decreased during the storage period, however, the use of the highest level of yogurt whey peptide (48.8 mg/mL) in the doogh formulation was able to reduce the rate of loss of sensory properties and maintain product quality over time. The sample containing 48.8 mg/mL bioactive peptide had the highest score of overall acceptability. Finally, the concentration of 48.8 ppm peptide can be considered as the best level to enrich the doogh in terms of physicochemical, microbial and sensory properties. Therefore, it is concluded that bioactive peptide derived from yogurt whey can be used as a natural antioxidant and antimicrobial agent in fermented dairy products like doogh.

    Keywords: Bioactive Peptide, Doogh, Antioxidant activity, Antibacterial Effect, Shelf Life
  • Hadis Cheraghi, Fardin Ghanbari *, Mehdi Saidi Pages 264-276
    Introduction

    Button mushroom (Agaricus bisporus L.) is one of the most popular and widely consumed edible mushrooms that is grown all over the world. However, button mushrooms have a short shelf life of about 3 to 4 days after harvest and lose their commercial value within a few days due to browning of the tissue, water loss, aging and microbial attack. Tissue browning is caused by the activity of polyphenol oxidase (PPO) in plastids on phenolic compounds in the vacuoles as a substrate. Therefore, enzymatic browning is intensified by the loss of membrane integrity due to aging and tissue deterioration and as a result of physical connection between the enzyme and the substrate. The use of some techniques such as the chemicals and physical treatments gives promising results in delaying Browning and increasing the shelf life of edible mushrooms. Cinnamic acid (CA) is an organic acid that occurs naturally in plants and has low toxicity and a wide range of biological activities. Cinnamic acid and its derivatives are widely used in food industry. This compound acts as an inhibitor of polyphenol oxidase activity. On the other hand, cinnamic acid in low concentration has been proposed as an activator of the antioxidant system and its positive effects on reducing the effects of environmental stresses in various plants have been proven in several experiments. Therefore, in the present study, the effect of cinnamic acid treatment on reducing the browning of the tissue and maintaining the quality of white button mushrooms in the post-harvest period has been investigated. 

    Materials and Methods

    Treatments included exogenous application of cinnamic acid at four levels (control, 100, 200 and 400 μM trans cinnamic acid) and storage time at five times (0, 4, 8, 12 and 16 days after storage). Cinnamic acid treatment at the mentioned concentrations was applied by top application 24 hours before mushroom harvest. Distilled water was used for control treatment. At the time of picking, infected, very large and small mushrooms were removed and the same mushrooms with a cap diameter of 40 to 45 mm were collected for each experimental treatment. After harvesting, the mushrooms were placed in a polyethylene box covered with cellophane and after weighing, they were transferred to an incubator at 4°C. In the post-harvest period, different traits were measured with a four day interva.

    Results and Discussion

    The results showed that by increasing storage time, the activity of polyphenol oxidase and peroxidase increased and consequently the browning of the tissue also had an increasing trend. Also, with increasing storage time, weight loss percentage, hydrogen peroxide and malondialdehyde increased and total phenol and total antioxidant capacity were decreased. The use of cinnamic acid treatment in all three concentrations (100, 200 and 400 μM) reduced the activity of peroxidase and polyphenol oxidase activities and reduced tissue browning. The application of cinnamic acid also improved the quality traits of edible mushrooms such as total phenol, total antioxidant capacity and visual quality index. These findings suggest that application of cinnamic acid, especially at a concentration of 400 μM, could have the potential of inhibiting tissue browning and thus maintaining the mushrooms quality at the postharvest period

    Keywords: antioxidant capacity, polyphenol oxidase, Tissue browning, Total phenol, Weight loss
  • Morteza Mohammadi *, Mohammad Ghorbani, Alireza Sadeghi Mahonak, Adel Beigbabaie, Samira Yeganeh Zad Pages 277-293
    Introduction

    Phenolic compounds are known as a base of many functional foods due to their antioxidant properties and salutary effects. Phenolic compounds mainly found in plant sources. Agricultural wastes are one of the cheapest sources for getting phenolic compounds. Pistachio is considered one of the most important agricultural products in Iran. Study on the different parts of solid wastes generated from pistachio processing is worthy due to containing valuable compounds. On the other hand, using novel techniques such as supercritical CO2, subcritical water, pulsed electric fields, etc., have gained more attention in the past few years. These technologies do not have side effects on the raw materials and final products; do not use chemical solvents such as hexane, methanol, acetonitrile, etc., in comparison to traditional extraction methods with the long time needed and using chemical solvents with hazardous effect on consumers. In this study, the subcritical water extraction method as a green technology was used for the extraction of phenolic compounds from pistachio hull using y response surface methodology.

    Materials and Methods

    In this study antioxidant properties of phenolic compounds extracted from pistachio hull by subcritical water fluid were evaluated. The extraction process is done at 120– 180 Celsius degree, pressure 10– 50 bar and ratio 1:10– 1:30 (sample to solvent) by using the subcritical water fluid method. The total phenolic compound, flavonoid compounds, reduction power, radical scavenging, and stability power of soybean edible oil were determined for each treatment. The stability power of extracts in soybean measured with rancimat test at 110 Celsius degree and airflow of 20 litter per minute. Comparison and statistical analysis for optimization of results accomplished using response surface methodology (RSM) by design expert software 7.0.0 version. After optimization, the results for optimum treatment were compared with BHT, ascorbic acid, and alpha-tocopherol. This comparison was done for reduction power, stability power, and radical scavenging ability.

    Results and Discussion

    The results showed that the total phenolic compounds changed from 7671.43 to 8903.57 mg Gallic acid equivalent per 100 g dry matter. Reduction power increased by increasing temperature from 120 to 150 Celsius degree and after that decreased. The effect of pressure on the phenolic compounds wasn’t remarkable. The amount of flavonoid compound was between 142.87 and 290.21 mg equivalent catechin per 100 g dry material. The most effective parameter among investigated parameters (temperature, pressure, and ratio), was temperature. The pressure of extraction in subcritical water extractions did not have any significant effect and every change in laboratory results was very small The best results were observed at 147 Celsius degrees, pressure 10 bar, and 1:19 ratio. In these optimum conditions, the amount of total phenolic compounds, total flavonoid compounds, stability power, radical scavenging power, and reduction power was 2497.8 mg gallic acid per 100 g dry material, 267.99 mg flavonoid compounds catechin equivalent per 100 g dry material, 7.44 h, 1370.77 ppm, and 362.94 ppm respectively. Reduction and stability power with radical scavenging ability of pistachio hull extracts were very near to BHT as well as a synthetic antioxidant. Results showed that the extracts obtained from pistachio hull by subcritical water had high amount of phenolic compounds and had the same antioxidant properties as the synthetic antioxidant BHT

    Keywords: Subcritical Water, Pistachio Hull, Novel technologies, Agricultural wastes, flavonoid compounds, stability power
  • Sara Forouzandeh, Mohammad Fazel * Pages 295-305
    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.

    Keywords: Nanoemulsion, Chia Seed Oil, Emulsifier, Antioxidant activity
  • Zahra Sheikholeslami *, Mahdi Karimi, Bahareh Sahraiyan Pages 307-329
    Introduction

    Doughnuts are fried foods that absorb significant amounts of oil, and commercial doughnuts made from wheat flour typically contain 24 to 26 percent oil. Fresh doughnut is soft and has a pleasant taste and aroma. One of the main ways to enrich bakery products is to mix wheat flour with other flours. Triticale has a higher percentage of protein compared to wheat, rice, corn, rye and oats and is in good condition in terms of essential amino acids. Lysine in triticale is higher than wheat and less than rye. Also triticale has the same amount of vitamins as wheat. The positive properties of gums extracted from native seeds such as basil can be used to reduce oil absorption and improve shelf- life of fried bakery products. Basil seeds are soaked in water due to the presence of polysaccharides, the outer pericarp swells and turns into a gelatinous substance. Green cardamom with scientific name of Elettaria cardamomum belongs to Zingiberaceae family. Cardamom is one of the most widely used aromatic condiments in some foods, breads, sweets, especially jams. 23 compounds have been identified in green cardamom essential oil, the highest composition (31.53%) belonging to Eucalyptol. Therefore, in this study, enrichment the wheat flour of fried fermented doughnuts by replacing part of wheat flour with triticale flour, reducing oil absorption by using basil seed gum and improving antioxidant and sensory properties and reducing fungal activity in the presence of green cardamom essential oil were investigated.

    Material and Methods

    In the first part of this research, Triticale flour at 0, 15 and 30% and Basil seed gum at 0, 0.50 and 1% were used to improve the quality and decrease oil absorption of fermented doughnut. Control doughnut  formulation had 500 g wheat flour, 20 g milk powder, 4 g salt, 80 g oil, 12 g baker’s yeast, 80 g sugar, 500 ml water, 100 g egg and 1 g vanilla, 1.5 % guar gum and 0.5 % xanthan gum.  Moisture, specific volume, porosity, firmness, crust color and oil absorption were evaluated. To study the effect of processing parameters on crust color components of doughnut, the RGB color space images were converted to L*a*b space. For determination of doughnut porosity using image analysis, the color images were first gray scaled and then thresholded using isodata algorithm. The porosity was measured from the ratio of white to the total numbers of pixels. Results were reported as the average of three replications. In the second part of this research, Cardamomum essential oil at 0, 50, 100, 150 and 200 ppm were used to improve antioxidant and sensory properties and decrease microbial contamination of doughnut. . In order to assess significant differences among samples, a complete randomized design of triplicate analyses of samples was performed using the Mini-Tab17. Tukey’s new multiple range tests were used to study the statistical differences of the means with 95% confidence.

    Result and Discussion

    The results of the first part showed that the sample contained 15% triticale flour and 0.50% gum with the highest specific volume (3.4 cm3g-1) and porosity (0.81) and the lowest firmness after one week of storage (11.91 N) and was introduced as the best example of the first part. Also, the results of oil absorption showed a decrease of 29.83% in the selected sample (0.17 g/g dry matter) compared to the control sample (0.24 g/g dry matter). The moisture content of the mentioned sample was 21.09% one week after production and L*, a* and b* of crust color was 55.27, 8.86 and 11.91, respectively. Brightness and redness of this sample was more than the control. The results of second part showed that cardamom essential oil had antioxidant activity in all concentrations. Also, the results indicated the concentrations of more than 50 ppm of cardamom essential oil can be considered as an antifungal agent and inhibit positive growth in doughnut. The microbial load of samples containing 100, 150 and 200 ppm had 3.97, 3.81 and 2.94 log cfu g-1 after 15 days of production, respectively. The microbial load of these samples was 51.05, 53.03 and 63.75% less than the sample without essential oil (10.11 log cfu g-1). Finally, the results of sensory evaluation showed that the sample containing 15% triticale flour, 0.50% basil seed gum and 100 ppm cardamom essential oil had the highest overall acceptance score and this sample is introduced as the best sample of this study.

    Keywords: Doughnut, Oil content, Basil seed gum, Triticale flour, Antioxidant
  • Seyed Amir Tavakoli Lahijani, Fakhri Shahidi *, Mahmoud Habibian, Arash Koocheki Pages 330-342
    Introduction

    Bread has a major role in the diet of people in Iran. One of the important factors affecting the quality of bread is the quality of wheat flour protein called gluten. Gluten is the principal structure forming elements of most baked products, contributing to the elasticity, cohesiveness and viscosity characteristics of the dough. Thus, gluten substantially control the quality of wheat flour based products. Due to the importance of the role of gluten and the requirement for improving the flour quality, providing a simple, economical, and efficient method to improve the technical quality of wheat and bread is also an important and controversial challenge. Oxidizing agents are generally added to the wheat flour to accelerate the natural maturing and the flour becomes paler and yields dough with improved baking properties. However, increasing concern about their adverse effects has highlighted the need for the development of alternative oxidants. Atmospheric cold plasma (ACP) is an emerging advanced oxidation process which has recently drawn considerable interest from food scientists. Therefore, the objective of this study was to investigate the effect of non-thermal plasma treatments on the properties of wheat flour.

    Materials and Methods

    For this purpose, medium wheat flour was prepared from local silages and treated with ACP at 25V for 0, 2, 4, 6, 8 and 10 min. Chemical composition of flour samples (moisture content, protein and ash) were determined using standard methods (AACC, 2002). Color properties, damaged starch water soluble index, wet gluten, gluten index, zeleny and falling number values, water and oil absorption capacities, swelling power and solubility of wheat flour samples were also measured.

    Results and Discussion

    The results obtained from the measurement of properties for the treated and untreated flour showed that the water and oil absorptions, swelling power, and solubility, wet gluten, gluten index, Zeleny number and whiteness increased significantly with increasing time, while the pH, moisture content, b * and a * indices, were decreased by plasma treatment. In addition, the results showed that ACP conditions have a significant effect on functional properties that can be created floursand products with various characteristics. The results showed that plasma treatment affected the gluten index and wet gluten and techno functional properties of wheat flour. Overall, this study demonstrated that non-thermal plasma is a quick, efficient way to improve the technological properties of wheat flour, as an alternative to chemical oxidants

    Keywords: Cold Plasma, Gluten, modification, Technological properties, Wheat flour
  • Sanaz Fallh-Taftizadeh *, Gholamreza Abdi, Fatemeh Zendeboodi, Mahdi Mohammadi Pages 343-365
    Introduction

    Virgin olive oil has high oxidative stability due to its special compounds, including large amounts of monounsaturated fatty acids (MUFAs) and a wide range of natural antioxidants. However, virgin olive oil is easily oxidized due to the presence of polyunsaturated fatty acids (PUFAs), mainly linoleic and linolenic acids. Lipid oxidation is the main cause of poor food quality; for this reason, the use of antioxidants is essential to prevent the onset and progression of oxidative damage and increase the shelf life of oils and fats. Because lipid oxidation occurs following a complex set of processes and no antioxidant alone can stop all the oxidation steps and keep oxygen away, a mixture of antioxidants can be used to create a synergistic effect. Spirulina is a dry biomass of Artrhrospira platensis cyanobacteria. Flavonoids, β-carotene, vitamin A and α- -tocopherol in spirulina are largely involved in the high antioxidant activity of this microalgae. The Moringa oleifera plant belongs to the Moringaceae family, the genus Moringa and the species Oleifera. This plant is considered as a high-potency natural antioxidant because it is rich in tocopherols, carotenoids, vitamin C, flavonoids and phenolic compounds. Therefore, the aim of this study was to investigate the synergistic and symbiotic effect of spirulina and M. oleifera extracts as natural antioxidants to increase the oxidation stability and shelf life of virgin olive oil.

    Materials and Methods

    To prepare the extracts of s. platensis and M. oleifera plant, both plants were dried in the shade at 30°C for 24 hours in the presence of air, then ground into a powder. Then, 5 g of s. platensis and M. oleifera powders were extracted with two solvent of ethanol (96%) and methanol. Antioxidant activity was evaluated by measuring the effect of free radical scavenging of ethanolic extracts of Algae Spirulina and Acacia on the synthetic radical DPPH. Determination of total phenol and flavonoid content of all extracts was performed using Folin-Ciocalteu reagent and aluminum chloride colorimetric method, respectively. Polyphenolic compounds of the extracts were identified by HPLC. Extracts were added separately (1000 ppm each) and in combination (500 ppm each) to 100g of virgin olive oil and a sample containing the synthetic antioxidant TBHQ and a sample of virgin olive oil were considered as control. Peroxide index, refractive index and color evaluation (L*, a*, b*) of virgin olive oil samples were measured. Statistical analysis was performed using SPSS software version 19 and the results were expressed as mean ± standard deviation.

    Results and Discussion

    Based on the results obtained from ethanolic and methanolic s. platensis extracts, the highest amount of total phenol in ethanolic extract was equal to 67.19±4.5 mg GA/g and the highest amount of flavonoids in methanolic extract was equal to 12/1±40/267 mg QU/g. In the study of the content of total phenol and flavonoids in ethanolic and methanolic extracts of M. oleifera plant, there was the highest levels of total phenols and flavonoids in ethanolic extracts of this plant, respectively, 43.43±0.71 mg GA/g and 23.78±1.57 mg QU/g. The results showed that the active compounds in the extracts of S. platensis and M. oleifera are polyphenolic compounds of rosmarinic acid, catechin, quercetin, vanillin, hesperidin, hesperetin. Changes in peroxide value from the time of production and addition of the extract for 8 hours at 2 hour intervals were investigated. According to the results, the lowest amount of peroxide value (0.38±0.005 meq O2/kg) was related to the sample containing M. oleifera extract at the third storage time. The highest amount of peroxide value was observed in the control and the sample containing TBHQ in the range of 15 meq O2/kg. Generally, Changes in peroxide value were reduced significantly in the 3 samples containing the extract compared to the control sample and the sample containing TBHQ (p<0.05). The presence of extracts in virgin olive oil reduced the parameters of L*a*b*, but the sample containing S. platensis extract was no significant difference from the control sample (p >0.05). According to the results of peroxide index of samples containing extracts, it can be stated that by recognizing the antioxidant effects of S. platensis and M. oleifera extract, they can be used for industrial use and replacement with synthetic antioxidants.

    Keywords: Virgin olive oil, Spirulina platensis, Moringa oleifera, synergitic, Antagonistic, Antioxidant
  • Sedigheh Yazdanpanah *, Sara Mohammadi, AmirHossein Elhami Rad Pages 367-382
    Introduction

    White tea is a new ingredient in a wide range of phenolic, antioxidant and antimicrobial compounds. The most important catechins in white tea are epicatechin, epigallocatechin, epicatechin- 3- galate, and epigallocatechin- 3- galate, which are flavonol gallates. The concentration of these phenolic compounds in white tea is higher than green tea. Sesame seed oil, which is produced by cold pressing method, has a great ability to preserve antioxidant compounds. Significant oxidative stability of sesame oil is due to the presence of lignan non-soapy substances. Strong antioxidant compounds in sesame seed oil include sesamol, sesamulin (antioxidant precursor), sesaminol and its isomers. The aim of this study was to investigate the effect of natural antioxidants of sesame oil and white tea on inhibiting the effect of metals on oxidation of sesame oil.

    Materials and Methods

    In this study, aqueous extract of white tea was extracted and sesame oil was produced using cold press. In the next step, six samples including control sample (sesame oil), sesame oil containing white tea extract, sesame oil containing white tea extract and 0.1 ppm iron, Sesame oil containing white tea extract and 0.1 ppm copper, sesame oil with tea and 0.1 ppm zinc extract and sesame oil containing 100 ppm BHT were prepared. In all samples, aqueous extract of white tea in the amount of 6 mg/ 10 g was added to sesame oil. Total phenol, antioxidant capacity, power reducing on white tea extract and antioxidant power, peroxide number, oxidation stability and fatty acids profile were measured. All experiments were performed in a completely randomized design with three replications and the means were compared with Duncan’s test at the level of (P<0.05). SAS V 9.1 software was used for statistical analysis of quantitative data.  

    Results and Discussion

    The results showed that the aqueous extract of white tea contained 4.06 (mg gallic acid per gram of sample) total phenol, 6.00 (μg/ ml) antioxidant capacity 0.020 (mg/ g). Ml) is a reducing power. The reducing power of BHT antioxidant was 40 times and the antioxidant power of BHT was 14.85 times more than the aqueous extract of white tea. In the inhibition of free radicals in sesame oil, the aqueous extract of white tea had a significantly greater effect than the control sample. The iron- containing sample had more oxidation than other samples. In the inhibition of free radicals in sesame oil, the aqueous extract of white tea had a significantly greater effect than the control sample. The iron- containing sample had more oxidation than other samples. Rancimat value for samples of control sesame oil, sesame oil with tea and iron extract, sesame oil with tea and copper extract, sesame oil with tea and zinc extract, sesame oil with tea extract and sesame oil with synthetic antuioxidant BHT respectively 8.79 4.80, 9.08, 9.35, 9.42 and 9.61 hours were measured. The highest stability was related to the sample of sesame oil and synthetic antioxidant BHT and the  Results and Discussion The results showed that the aqueous extract of white tea contained 4.06 (mg gallic acid per gram of sample) total phenol, 6.00 (μg/ ml) antioxidant capacity 0.020 (mg/ g). Ml) is a reducing power. The reducing power of BHT antioxidant was 40 times and the antioxidant power of BHT was 14.85 times more than the aqueous extract of white tea. In the inhibition of free radicals in sesame oil, the aqueous extract of white tea had a significantly greater effect than the control sample. The iron- containing sample had more oxidation than other samples. In the inhibition of free radicals in sesame oil, the aqueous extract of white tea had a significantly greater effect than the control sample. The iron- containing sample had more oxidation than other samples. Rancimat value for samples of control sesame oil, sesame oil with tea and iron extract, sesame oil with tea and copper extract, sesame oil with tea and zinc extract, sesame oil with tea extract and sesame oil with synthetic antuioxidant BHT respectively 8.79 4.80, 9.08, 9.35, 9.42 and 9.61 hours were measured. The highest stability was related to the sample of sesame oil and synthetic antioxidant BHT and the lowest stability was related to the sample of sesame oil with tea and iron extracts. In comparison with the effect of metals on the oxidation of sesame oil, the addition of iron to sesame oil has increased the oxidation rate compared to the two other examined metals (copper and zinc). Rare metals increase the oxidation rate of edible oils by increasing the production of free radicals from fatty acids or hydroperoxides. The composition of of fatty acids profile showed that palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid were the predominant fatty acids in sesame oil. In the iron- containing sample, with increasing oxidation rate, the amount of linolenic acid decreased compared to other samples. The results of the Se index were confirmatory on the results of oxidative stability index. White tea extract and sesame oil due to their antioxidant and phenolic compounds have been able to inhibit free radicals and metal peroxidants, especially copper and zinc. Sesame oil extracted by cold pressing is not suitable for frying due to its low heat resistance, but it can be used in the formulation of salad dressings.

    Keywords: Antioxidant, Metal catalyst, Oxidative Stability, Sesame oil