فهرست مطالب
مجله علوم و صنایع غذایی ایران
سال پانزدهم شماره 6 (پیاپی 79، شهریور 1397)
- تاریخ انتشار: 1397/06/06
- تعداد عناوین: 30
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- علمی پژوهشی
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صفحات 1-10
آنزیم ترانس گلوتامیناز با ایجاد اتصال عرضی در پروتئین ها و تقویت ساختار مبتنی بر پروتئین، تاثیر مثبتی بر ظرفیت نگهداری سرم و استحکام ژل در مواد غذایی دارد. اینولین به پلیمرهای فروکتوز با درجه پلیمریزاسیون 2 تا 60 اطلاق می-شود که توسط پیوندهای فروکتوزیل (1-2) β به هم متصل شده اند. ویژگی های پری بیوتیکی و بیفیدوژنی این ماده سبب شده تا از آن به عنوان یک ماده فراسودمند در محصولات غذایی استفاده شود. این پژوهش با هدف بررسی اثر افزودن آنزیم ترانس گلوتامیناز و اینولین بلند زنجیر بر ویژگی های فیزیکی شیمیایی و حسی دوغ انجام شد. در این پژوهش، اثر آنزیم ترانس گلوتامیناز در غلظت (3/0-0 %) و اینولین بلند زنجیر در غلظت (5/1-0%) در قالب 5 تیمار دوغ بر ویژگی های فیزیکی شیمیایی (pH ، اسیدیته، ماده خشک بدون چربی، دانسیته، میزان جدایی فاز سرم و ویسکوزیته) و ویژگی های حسی (قوام ، طعم، رنگ و پذیرش کلی) در 24 ساعت و 30 روز پس از تولید مورد بررسی قرار گرفت. نتایج نشان داد که با افزایش اینولین و آنزیم، هیچ تفاوت معنی داری در اسیدیته، pH و طعم میان نمونه کنترل و سایر تیمارها پس از 24 ساعت و 30 روز مشاهده نگردید (05/0P>). اما از لحاظ شاخص های دانسیته، ماده خشک بدون چربی، میزان جدایی فاز سرم، ویسکوزیته و پذیرش کلی نمونه های 3R (5/1% اینولین و 3/0% آنزیم) و 4R (5/1% اینولین و 1/0% آنزیم) نسبت به نمونه کنترل، برتری معنی داری نشان دادند (05/0P<).
کلیدواژگان: آنزیم ترانس گلوتامیناز، اینولین بلند زنجیر، دوغ -
صفحات 11-20سس سالاد از امولسیون های غذایی مهم در رژیم غذایی روزانه ما محسوب می شود و به دلیل داشتن زرده تخم مرغ در فرمولاسیون، حاوی مقادیر بالای کلسترول و اسیدهای چرب اشباع هستند. در این پژوهش، ویژگی های فیزیکی، شیمیایی و آنتی اکسیدانی سس سالاد بدون زرده تخم مرغ بررسی گردید.
امولسیون روغن در آب با استفاده از روغن زیتون بکر و سرکه سیب آماده و به وسیله صمغ زانتان با درصدهای (25/0٪T1: ، 5/0٪T2: ، 75/0٪T3:) پایدار شدند. ویژگی های دو فاز شدن، pH، اسیدیته، مقدار اسیدهای چرب آزاد، ترکیبات فنلی کل و درصد مهار رادیکال های آزاد DPPH اندازه گیری و ویژگی های حسی سس های تهیه شده ارزیابی گردید. در طول 90 روز نگهداری در دمای 4 درجه سانتی گراد، هیچگونه جدایی فاز در نمونه ها دیده نشد. pH، اسیدیته و مقدار اسیدهای چرب آزاد همه نمونه ها در طول زمان نگهداری در محدوه استاندارد ملی ایران قرار داشت. محدوده ترکیبات فنلی کل و درصد مهار رادیکال های آزاد DPPH به ترتیب بین 44 تا 54 میلی گرم در کیلوگرم و 89 تا 92% بود. نمونه های حاوی 5/0و 75/0% بالاترین امتیاز ارزیابان حسی را دریافت کردند. نتایج نشان داد که تیمار T2 و T1 مناسب ترین ویژگی های فیزیکی و شیمیایی و اکسیداسیونی را داشتند و میتوانند بهعنوان سس سالاد بدون تخممرغ، در بازار مصرف عرضه شود.کلیدواژگان: ویژگی های اکسیداسیونی، صمغ زانتان، ویژگی های شیمیایی، پایداری امولسیون، ترکیبات فنلی -
صفحات 21-29باگاس، تفاله نیشکر است که پس از عصاره گیری از نیشکر به صورت پسماند فیبری خشک، فشرده و به صورت قطعات ریز تراشه به دست می آید. الیاف باگاس برای تولید سوخت، مواد شیمیایی، آنزیم ها و مواد غذایی نیز قابل استفاده می باشد. در این پژوهش تاثیر جایگزین نمودن مقادیر (0، 5، 10، 15، 20 و 25 درصد) باگاس فرآوری شده بر خصوصیات شیمیایی (رطوبت، خاکستر، فیبر)، ویژگی های کیفی (بافت، تخلخل، دانسیته و شاخص حجم، رنگ پوسته و مغز) و ارزیابی حسی کیک مورد بررسی قرار گرفت. آزمون ها بر اساس طرح کاملا تصادفی و در سه تکرار انجام شد. نتایج نشان داد با افزایش درصد پودر فیبر باگاس در کیک، رطوبت، خاکستر، فیبر، سفتی و چسبندگی نمونه ها افزایش یافت و کاهش تخلخل، روشنایی، دانسیته (افزایش حجم مخصوص) نسبت به نمونه شاهد مشاهده گردید (05/0P<). در نهایت با بررسی همه ی ویژگی ها، نمونه حاوی 5 درصد پودر فیبر باگاس به عنوان نمونه بهینه معرفی گردید که از سوی ارزیاب ها نیز مورد پذیرش بیشتری نسبت به سایر تیمارها و تیمار شاهد قرار گرفت. به طور کلی به دلیل خصوصیات تغذیه ای و حسی فرآورده حاصل از فیبر باگاس، می توان از این ماده به عنوان یک منبع فیبر رژیمی در فرآورده های غذایی استفاده کرد.کلیدواژگان: فیبر رژیمی، بازیافت ضایعات، نیشکر، فراسودمند
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صفحات 31-41استفاده از غلظت مناسب مواد اولیه از جمله پلیمر و نرم کننده برای بدست آوردن بهترین ویژگی های فیزیکی و مکانیکی فیلم های خوراکی به منظور بسته بندی و نگهداری مواد غذایی ضروری است. هدف از مطالعه حاضر بدست آوردن بهترین ترکیب پلیمر و نرم کننده به منظور تولید فیلم کتیرا براساس ویژگی های فیزیکی، مکانیکی و ساختاری فیلم می باشد. بدین منظور ابتدا ویژگی های فیزکی، مکانیکی و ساختاری فیلم کتیرا در غلظت های مختلف 5/0، 75/0، 1و 25/1 بررسی شد. نتایج نشان داد افزایش غلظت پلیمر سبب افزایش ضخامت، نفوذ پذیری بخار آب، حداکثر کشش تا قبل از نقطه پارگی، از فیلم شد و همچنین سبب کاهش زاویه تماس و انتقال عبور نور شد. با توجه به نتایج، غلظت های مختلف گلیسرول شامل 20، 30 و 40 درصد به فیلم کتیرا با غلظت 75/0% افزوده شد. غلظتهای کمتر گلیسرول خواص مکانیکی، ساختاری و فیزیکی بهتری را نشان داد. در مجموع بهترین غلظت ترکیبی کتیرا و گلیسرول در مطالعه حاضر به ترتیب 75/0% و 20% بوده است.کلیدواژگان: فیلم خوراکی، کتیرا، گلسیرول، ویژگی های فیلم
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صفحات 43-54هدف این تحقیق بررسی اثر غلظت های مختلف آب پنیر و محیط کشت والنه جهت تولید بیومس Dunaliella salina و ارزیابی خصوصیات بیوشیمیایی آن بود. بدین منظور سه فاکتور شامل غلظت محیط کشت والنه (صفر تا 50 میکرولیتر)، درصد آب پنیر (صفر تا 5 درصد) و زمان گرمخانه گذاری (صفر تا 14 روز) در قالب طرح باکس بانکن شامل 17 نمونه مورد مطالعه قرار گرفت. نتایج نشان داد با افزایش درصد آب پنیر و همچنین محیط کشت والنه، تراکم سلولی افزایش یافت ولی این افزایش از نظر آماری معنی دار نبود (05/0
کلیدواژگان: دونالیلا سالینا، آب پنیر، محیط کشت والنه، بیومس، کلروفیل
در این پژوهش آزمایشگاهی اثر اختلاف فشار در عرض غشاء در سه سطح (10، 15 و 20 بار) ، pH در سه سطح (4 ، 5 و 6) و دما در سه سطح (30 ، 40 و 50 درجه سانتی گراد) بر میزان شار تراوه و گرفتگی غشاء در طی فرایند نانو فیلتراسیون پساب حاصل از کارخانه رب گوجه فرنگی بررسی شد. . از روش سطح پاسخ بر مبنای قالب آزمایشی D-optimal برای ایجاد طرح آزمایشی و آنالیز داده های تجربی استفاده گردید. نتایج نشان دهنده مناسب بودن مدل چند جمله ای درجه دوم برای پیش بینی میزان شار تراوه و گرفتگی غشاء می باشد (ضریب تبیین به ترتیب 96/0 و 93/0)، همچنین نتایج نشان دهنده عدم معنی داری آزمون ضعف برازش و میزان بالای ضریب دقت می باشد.. میزان تابع مطلوبیت برای عملیات بهینه سازی 89/0 و شرایط بهینه عملیاتی به ترتیب در اختلاف فشار در عرض غشا 20 بار، دمای 30 درجه سانتی گراد و 6/5pH = به دست آمد. همچنین تفاوت معنی داری بین نتایج به دست آمده از روش سطح پاسخ و داد های تجربی در نقطه بهینه مشاهده نشد.
از مخلوط آردهای سورگوم و نشاسته سیب زمینی با نسبت های 1:3، 1:2 و 1:1 و صمغ زانتان با مقادیر 0، 5/1 و 3 درصد برای تهیه نان باگت استفاده شد. آنگاه ویژگی های رئولوژیکی خمیر و ویژگی های ارگانولپتیکی، رنگ، حجم، بافت و بیاتی نان در زمان های 1، 36 و 72 ساعت پس از پخت تعیین گردید. پس از آن نتایج با استفاده از روش آماری سطح پاسخ با طرح فاکتوریل کامل و توسط نرم افزار Design Expert در سطح معنا داری 95 درصد مورد تجزیه و تحلیل قرار گرفتند.
نتایج نشان دادند که با افزایش نسبت آرد سورگوم و نشاسته سیب زمینی و درصد زانتان، میزان جذب آب آرد، زمان عمل آوری خمیر، پایداری خمیر، عدد کیفیت فارینوگراف افزایش مییابد. اما با افزایش نسبت آرد سورگوم و نشاسته سیب زمینی، انرژی اکستنسوگراف و قابلیت کشش خمیر، کاهش ولی با افزایش صمغ زانتان، افزایش مییابند. درحالیکه عدد نسبت اکستنسوگراف، با افزایش نسبت آرد سورگوم و نشاسته سیب زمینی افزایش و با افزایش صمغ زانتان، کاهش مییابد. ویژگی های حسی و بافتی نان حجیم تولید شده نیز با افزایش نسبت آرد سورگوم و نشاسته سیب زمینی و همچنین افزایش صمغ زانتان، بهبود مییابند. ضمن اینکه افزایش نسبت آرد سورگوم و نشاسته سیب زمینی و صمغ زانتان موجب افزایش مدت ماندگاری نان حجیم حاصل میشود.
آلودگی پسته به آفلاتوکسین یکی از معضلات تولیدکننده های پسته است و پسته در بین تمام محصولات کشاورزی، یک خطر بالای آلودگی به آفلاتوکسین را دارد. در ایران بیشینه سطح قابل قبول، برای آفلاتوکسین B1و آفلاتوکسین کل8 و 10 پی پی بی به ترتیب است. یکی از راه های جلوگیری از تولید این سم خطرناک، امکان عدم رشد قارچ های مولد آفلاتوکسین و به دنبال آن تولید نشدن سم آفلاتوکسین است. برای این منظور چهار رقم پسته استان کرمان از اداره استاندارد با تاییدیه نداشتن آفلاتوکسین، تهیه و پس از آغشته شدن با غلظت مناسبی از اسپور قارچ آسپرژیلوس فلاووس و آسپرژیلوس پارازیتیکوس، بسته بندی و در سازمان انرژی اتمی ایران مورد پرتودهی گاما در دزهای 3و 5 و9کیلو گری قرار گرفتند. طبق نتایج به دست آمده، با افزایش دز پرتودهی، حذف اسپور قارچ های مولد آفلاتوکسین، افزایش یافت و در طول انبارداری تا 9 ماه هم امکان رشد فراهم نشد به طوری که میزان آفلاتوکسین اندازه گیری شده صفر گزارش شده است. در نمونه های شاهد علاوه بر رشد اسپور قارچ،که کاملا در ظاهر قابل مشاهده بود، میزان تولید آفلاتوکسین هم به میزان خیلی زیادی گزارش شده است که از استاندارد خارج است. ارزیابی حسی نشان داد که تا دز 5 کیلو گری تغییر غیرقابل قبولی در طعم پسته ها ایجاد نشد و بین تیمار شاهد و تیمارهای پرتودیده تا 5 کیلو گری هیچ اختلاف معنی داری وجود نداشت(p<0/05). نتیجه گیری کرد که میزان دز مناسب پرتوگاما برای حذف اسپور قارچ های مولد آفلاتوکسین و طعم مناسب پسته 5کیلو گری است.
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Pages 1-10
Through ceating crosslink in proteins, and strengthening the protein-based food structures, MTGase can positively affect the serum holding capacity and gel firmness properties of foods. Inulin is fructose polymers with 2 to 60 degree of polymerization that linked by β (2-1) fructosyl bonds. Prebiotic and bifidogenic features of this matter have caused to use it as a functional ingredient in food products. The purpose of this study was to study the effect of the addition of MTGase and long-chain inulin on the physicochemical and sensory properties of doogh. In this study, the effect of using MTGase (0-0.3%) and long-chain inulin (0-1.5%) in 5 samples of doogh was examined on physicochemical (pH, titratable acidity, density, SNF, viscosity and phase separation) and organoleptic properties (consistency, flavor, odor, color and overall acceptability). Evaluations were performed at 24 hours and 30 days of storage. The results revealed that with increase of Transglutaminase and inulin no significant difference in pH, acidity, flavor, odor between the control sample and other treatments containing inulin and MTGase after 24 hours and 30 days was observed (P>0.05). The viscosity, SNF, density, serum phase separation, consistency and overall acceptability of samples R3 (1.5% inulin and 0.3% MTGase) and R4 (1.5% inulin and 0.1% MTGase) shown superior physicochemical and sensory properties.
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Pages 11-20Salad dressings are food emulsions important in our daily diet, but conventional salad dressings have high amounts of cholesterol and saturated fatty acids because of egg yolk in their formulations. This study investigated the physicochemical and antioxidant properties of the salad dressing without egg yolk. Oil-in-water emulsions were prepared with virgin olive oil and apple vinegar stabilized with various percentages of xanthan (T1: 0.25%, T2: 0.5%. T3: 0.75%).Characteristics including phases separation, pH, acidity, free fatty acids, total phenolic compounds, and DPPH free radical control inhibition were measured and the sensory properties of the prepared sauces were evaluated. Results showed that all samples within 90 days preservation at 4°c was not observed phase separation during storage. pH, acidity and free fatty acid all samples were in the range of Iranian National Standard and they were within this limit during storage too. The ranges of total phenolic compounds and the DPPH test indicated in salad dressings are (44 52 mg per kg) and (89 - 92 percent) respectively.Samples containing 0.5% and 0.75% Xanthan received the highest score of sensory evaluators. Results showed that T2 and T1 had the optimum physicochemical and oxidative properties and can be a proper egg yolk free salad dressing to introduce to the market.Keywords: Oxidative properties, Xanthan gum, Chemical properties, Emulsion stability, Phenolic compounds
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Pages 21-29Bagasse is a waste from sugar cane extraction, which is obtained as dry, compressed, and finely chopped fiber fragments. Fiber bagasse for the production of fuels, chemicals, enzymes and food is also available. In this study, the effect of adding 0, 5, 10, 15, 20 and 25% bagasse powder on the chemical (moisture, ash, and fiber), the qualitative (texture, porosity, density and volume indicator, Crust color and Crumb) and sensory characteristics were investigated. A test based on a completely randomized design with three replications. Results showed that by increasing the percentage of fiber powder in the cake bagasse fiber, moisture, ash, fiber, stiffness and adhesion was increased and porosity, brightness, density decreased compared to control samples (pKeywords: Dietary fiber, Waste products recycle, Sugarcane, Functional
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Pages 31-41Appropriate concentration of base material and plasticizer is required to obtain good physical and mechanical properties of edible film for food packaging and preservation functions. The aim of this study was to obtain the best combination of the base material and plasticizer in the manufacture of tragacanth films based on physical, structure and mechanical properties. For this reasons at the first the mechanical, structure and physical properties of different concentrations of tragacanth (0.5, 0.75, 1 and 1.25%) were studied. The results showed, increasing tragacanth concentrations resulted in the increase in the film thickness, elongation at break (E) and water vapor properties, but decreased the contact angle and transmittance of film. According to the results the best concentration of tragacanth was 0.75%, and different concentration of glycerol (20, 30 and 40%) was added to this film. The results showed that, tragacanth film with lower concentration of glycerol had the better mechanical, structure and physical propertis. All in all, the best concentration combination of tragacanth and glycerol in this study was 0.75 and 20%, respectivelyKeywords: Edible films, Tragacanth, Glycerol, Film properties
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Pages 43-54The aim of this study was to investigate the effects of different concentrations of cheese whey and Walne culture medium to produce Dunaliella salina biomass and evaluation of its biochemical properties. For this purpose, three factors including the concentration of Walne culture medium (0-50 μl), the percentage of cheese whey (0-5 %) and incubation time (0-14 days) using Box-Behnken design with 17 Runs were studied. Results showed that increasing of cheese whey percentage and Walne culture medium caused to increase cell density but it was not statistically significant (p>0.05). Increasing of the Walne culture medium led to increasing chlorophyll and carotenoids and showed a significant difference (p0.05). Significant differences were observed between the different treatments in producing cell density (p0.05). Optimum conditions were obtained on day 5 of incubation, 5 percent of cheese whey and zero percent of the Walne culture medium. In the mentioned condition the amount of cell density, protei and carotenoid was 2.7410, 288.75 mg/kg, 0.202 mg/ml respectively.Keywords: Dunaliella salina, Cheese whey, Walne medium, Biomass, Chlorophyll
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Pages 55-66
In this Research, the effects of transmembrane pressure at three levels (10, 15, 20 bar), pH at three levels (4, 5, 6), temperature at three levels (30, 40, 50 oС) on the permeate flux and the fouling during the nanofiltration of wastewater obtained from tomato paste plant were investigated. Response surface methodology (RSM) based on the D-optimal design was employed to arrange the experiment design and to analyze the experimental data. The results demonstrated that the quadratic polynomial models are highly promising for modelling the permeate flux and fouling (R2 equal to 0.96 & 0.93, respectively). In addition, the results demonstrated that the lack-of-fit tests have been found to be insignificance in all cases, along with high values for the adequacy precision. The desirability function has been achieved as 0.89. The optimum condition has been found as following: the pressure of 20 bars, temperature of 30 oС, and pH of 5.6, respectively. There was no significant difference between experimental and predicted values in the optimum condition.
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Pages 67-77The major factor to improve wheat flour and bread is gluten that causes improvement of texture and bread volume. But, this protein is dangerous for coeliac disease. With regard to, bread is staple food in majority of people, so, the aim of this research is to produce gluten free baguette with high nutrition values and favorable quality, by using a mixture of sorghum flour and potato starch and xanthan gum. So a blend of sorghum flour and potato starch with ratios of 3:1, 2:1, 1:1, and xanthan gum with percentages of : 0, 1.5, 3 % were used. Then the specifications of dough and bread were evaluated. Then rheological properties of dough, were determined by farinograph and extensograph in triplicate. Baguette was baked from treatments and were evaluated sensory, organoleptic characteristics, colour, volume, texture and staling of bread in 1, 36 and 72h after baking. Results were analysed by factoriel method and Minitab in 95% confidence level. The results showed that by increasing the ratio of sorghum flour and percentage of xanthan, water absorption percent of flour, dough development time, stability and farinograph quality number will increase. By increasing the ratio of sorghum flour, energy of extensograph and resistance to extension of dough will decrease. While by increasing percent of xanthan gum, these parameters will increase. But by increasing the ratio of sorghum flour, ratio number of extensograph will increase and by increasing xanthan, it will decrease. Also by increasing the ratio of the sorghum flour and potato starch and xanthan gum, The sensory and the texture specifications of baguette will improve. whereas increasing the ratio of sorghum flour, potato starch and xanthan gum will lead to increase the shelf life of the produced bread.Keywords: Gluten Free Bread, Sorghum flour, Xanthan gum, Potato starch
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Pages 79-90
Aflatoxin contamination is one of the main problems for producers, and when compared with other farm produce, pistachio has the highest risk of aflatoxin contamination. In Iran, the maximum acceptable levels of aflatoxin B1 and total aflatoxin are 8 and 10 ppb or nanograms per grams respectively. One way to prevent this dangerous poison is to provide a situation in which there is no possibility for aflatoxin generator fungi to grow. To this end, four aflatoxin-free pistachio cultivars, grown in Kerman, were taken from the Institute of Standards and Industrial Research of Iran. Following the impregnation with the Aspergillus flavus and Aspergillus parasiticus fungal spores were packed and gamma irradiated in 3, 5, and 9-kilo gray doses at the Atomic Energy Organization of Iran. The results revealed that the increase in radiation dose resulted in removal of aflatoxin generator fungi, and there was no possibility for their growth during the 9-month storage period, thus the aflatoxin production was reported to be zero. In the control sample, however, the fungal spore increased, and the aflatoxin production was reported to be higher than the standard. Sensory evaluation revealed that there was no marked change in the pistachios taste up to the 5-kilogray dose, and there was no significant difference between the control sample and up to the 5-kilogray irradiated treatments (p
Keywords: Gamma irradiation, commercial pistachio, aflatoxin, aflatoxin producing fungi, sensory analysis -
Pages 91-101In the current study, the percentages of 0, 0.25, 0.5, 0.75, 1, 1.25, 1.75 and 2% whey powder were used for yoghurt production. The physicochemical, sensory and microbial properties of samples were analyzed at 1 and 14 day of storage at 4°C. Chemical analysis showed that the higher whey powder decreased protein, pH and moisture content, while the amount of ash, acidity and reducing sugar increased. Based on the results of sensory evaluation, the highest sensory scores were obtained by replacing 0.5 and 0.75% whey powder (samples 2 and 3). This ratio can be used to reduce production costs. In addition, the microbial analysis illustrated that the samples were prepared from higher ratios of whey powder, the counts of S. thermophilus and L. delbrueckii were higher than the other samples.Keywords: Whey powder, Chemical properties, Sensory evaluation, Starter cultures
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Pages 103-110Dried and powdered onionshave many applications in food production.But during onion drying, nonenzymatic browning reaction happens which decreases its quality. In this study, different pretreatments before onion drying were used to prevent destructive reactions. After pealing and grating the onions, they were treated with three treatment methods of sodium metabisulphite 0.5%, citric acid with pH=4 and 10% salt (NaCl) for two minutes. Then, the treated onions were dried at cabinet dryer at two temperatures of 800C and 900C till reaching moisture content of 6 and the produced powders were kept for two months at room temperature and qualitative tests were carried out on them at days 1,30 and 60. Results showed that the pretreatments had significant effects(pKeywords: Onion powder, Pretreatment, Drying, Durability, Qualitative features
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Pages 111-120Food products in addition to the desirable sensory properties, must have suitable nutritional condition for being in diet. So producing composite products is practical solutions to improve the nutritional value and create diversity and selecting appropriate wheat flour replacement in bakery products is so important. Chestnut is the most important crops in temperate regions. Chestnut containing high amount of dietary fiber, essential amino acids and vitamin, so was applied in levels of 0, 15 and 30% as wheat flour replacement in cake formulation in this study. Sodium stearoyl 2- lactylate (SSL) emulsifier used in level of 0, 0.2 and 0.4%. Technological, textural, visual and sensory properties of cake sample were analyzed in completely randomized design by factorial arrangement (p≤0.05). The results showed all quantitative and qualitative properties of cake were improved by increasing the amount of SSL. On the other hand moisture content, crust L* and a* values and firmness were increased by adding 30% chestnut. While the highest amount of specific volume, porosity and texture softness were observed in sample containing 15% chestnut. Finally the sample containing 15% chestnut flour and 0.4% SSL had the highest score of overall acceptance in sensory evaluation.Keywords: Chestnut, Emulsifier, Functional cake, Diet fibre
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Pages 121-131The aim of the research was to study the effect of pasteurization temperature, storage time and carrot juice ratios on pasteurized cow milk enriched with carrot juice. For this purpose, after carrot juice extraction and filtration, different ratio of carrot juice (10, 20, 30, 40 and 50 %) were added to pasteurized cow milk and mixed properly. Then samples were filled in glass bottles and pasteurized at different temperatures (65, 70 and 75 °C) for 30 min. The samples were quickly cooled and stored at 4 °C up to 13 days. The bioactive compounds (total carotenoids (ß-carotene equivalent), total phenols (Gallic Acid equivalent) and vitamin C) and were analyzed during storage time (1, 4, 7, 10 and 13th). The results showed that the carotenoid, vitamin C and total phenol content of milk carrot drinking were increased by increase of carrot juice ratio. Furthermore, higher pasteurization temperature resulted in higher loss of carotenoids, total phenols and vitamin C in samples. Also, during storage time, the amount of carotenoids, total phenols and vitamin C in samples were decreased due to oxidation, deformation or interaction with other compounds. Stability and phase separation test of samples showed that all of treatments are stable during storage time. The results showed that increase of carrot juice and pasteurization temperature resulted in increase and decrease of bioactive compounds respectively and proper shelf-life of milk-carrot drinking samples were 10 days.Keywords: Cow milk, Carrot juice, Stability, Bioactive compounds, Storage time
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Pages 133-141Application of ultrasoundpower and its beneficial effects on food process and improved quality compared with conventional methods already have been demonstrated. In the currentstudy, the effects of ultrasound power intensity (200, 300, 400 and 500watts) at 15 and 30 minutes withdifferent storage temperature (28°C and 4°C) on Doogh pH, turbidity, fat percentage and stability was assessed. The results showed that increasingultrasound intensity and duration, caused pH reduction compared to the control,while in 400 watts sonication intensity and 4°C treatment,,samplesturbidityhad the lowest value. In comparison to control samples, there were no significant differencesin fat contentofall sonicated treatments. Also results illustrated thatall sonicated treatments had the higher stability and increasing ultrasound intensity and duration, increasedDooghstability. According to the finding, the optimal treatment during 30 minutessonication at 400 W,28°C and 4°C had the most consistency on treated Doogh samples.Keywords: Ultrasound, Doogh, Physico-chemical properties, Stability
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Pages 143-156The objective of the present study was to investigate the effects of the emulsifier diacetyl tartaric acid ester of monoglycerides (DATEM, 0.5 and 1%) and maltogenic α-amylase (MALTO, 0.01 and 0.1%) separately and combined on the physical (specific volume, physical indices, oven spring and parameters related to porosity) and textural properties of pan bread. A sample without the addition of emulsifier or enzyme was considered as control bread. The results showed that, compared to control, a combination of emulsifier DATEM and α-amylase led to significant increase in specific volume (p0.05) reduced the crumb firmness and significant decrease of firmness obtained for a combination of emulsifier and enzyme (pKeywords: DATEM, Enzyme, Pan-bread, Staling
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Pages 157-169This study was investigated whit aimed to the effect of different walls including Lepidium sativum and Lepidium perfoliatum and a combination of both gums for nano-capsulation of citrus essential oil, in order to maximize the efficiency of encapsulation and the stability of emulsion. For this purpose, emulsion containing 4% orange peel oil in aqueous solution containing 1% (w/w) of the total composition of the substance wall was prepared with the help of ultra-thoracic and ultrasound and then it was dried by freeze dryer. Stability of emulsion was measured by calculating the particle size, the percentage separation of emulsions, zeta potential and apparent viscosity and the nano-capsules quality was evaluated by determining efficiency of nano-capsulation, water activity and colorimetric. Reports of tests had indicated that due to the change in the type of wall, emulsion and powder characteristics were changed. Particle size of mixed emulsion (Lepidium sativum and Lepidium perfoliatum) was reported smaller than two other examples. As a result, the desired emulsion was more uniform. In addition, the results showed that with increasing viscosity in the gum, the efficiency of nano-capsules was increased. In terms of colorimetric characteristics, Powder containing Lepidium sativum seed gum had a higher brightness parameter than the other two Powders. Finally, the investigation of nano-capsule structure with scanning electron microscopy had showed that the nanoparticles was spherical and regular in all three samples.Keywords: Nano-capsulation, Essential oil of orange peel, Lepidium sativum, Leidium perfoliatum, Freeze Dryer
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Pages 171-182Fat oxidation is considered as the most important reason for food spoilage.Oxidative stability and physicochemical properties of pumpkin seed oil (PSO), soybean oil (SBO), palm olein (PO) and their blends were evaluated.For this purpose, viscosity changes and free fatty acid were studied for all the samples during the heating process at 170 ° C for 18 hours. In addition to oxidative stability were studied By Rancimat at temperatures of 110, 130 and 160 ° Cfor all samples. The results showed that any of the individual investigatedoils in pure form undergone more changes in viscosity rather than when it was blended with other oils. So that the lowest rate of change in viscosity was seen for PSO: PO (50:50) and PSO: SBO: PO (33/3:33/3:33/3) blends. The lowest rate of formation of free fatty acids were determined for PSO: SBO (50:50) and PSO: PO (50:50). The results showed that, as with viscosity, the blending of the oils decreased the rate of formation of free fatty acids as compared with any individual oils. In general,different blends of PSO showed the highest induction time (IT) In Rancimat test. PSO: SBO (30:70) had the lowest IT, inwhich, IT of this blend significantly (05/0> P) increased by increasing the proportion of PSO. The results of this study favorablyshowed that PSO blended with other oils could help to improve the oxidation stability and nutritional properties of the blended oils.Keywords: Pumpkin seed oil, Oil blends, Physicochemicalproperties, Oxidative stability
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Pages 183-190In recent years, the consumers and producers interest and demand for functional food products has been on the rise. The increase in cardiovascular diseases and cancer has been attributed to inappropriate food diet and poor nutrition. Chocolate is a product containing a great deal of fat and energy. In order to improve the nutritional value of this product and to assist human health, the addition of unsaturated flaxseed fatty acids to chocolate has been studied. In this research, Omega-3 has been added in 4 levels of 8, 12, 16, 20 gm to 100 gm of chocolate and all the properties have been compared to the control lacking Omega-3. Then the amount of fat content, sugar content, moisture, ash, iodine value, peroxide value, apparent viscosity, Rheological properties, sensory auditing and microbiological analysis were investigated. The chemical tests results revealed a meaningful increase in the fat content of all samples that it rose from 37.7 % in the control to 43.3 % in the sample containing 20 gm of Omega-3. Statistically, the moisture amount faced a meaningful fall which reached 0.16 % from 0.37 %. Moreover, the iodine value had a significant rise that increased from 33.73 to 37.6 while the percentage of sugar content, ash and peroxide value almost remained unchanged. the desirability of the first and second treatments were assessed higher by auditors. Finally, all treatments are within the standard range in terms of microbiological assessments.Keywords: Milk Chocolate, Omega 3, Functional Properties, Physicochemical Properties, Sensorial Evaluation
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Pages 191-201In recent years, due to consumer interest in natural, low sugar, functional and high nutritional products, so researchers in the food industry are focused on the food redesign. Studies have reported the health promoting of Stevia and prebiotic compounds which are well known as beneficial agents. The aim of this study wasto optimize the production of low-calorie and prebiotic carrot jam. For this purpose the three independents variable including Steviain three levels (0.05, 0.15,0.25)%, sugar in three levels (35,45 and 55)%, Inulin in three levels (2, 3 and 4) and pectin is at fixed level in 0.5% were studied. Treatments in the response surface methodology (RSM) were analyzed. Chemical properties includingpH, acidity, moisture, final brix in carrot jam were evaluated by Iranian national standard methods after 1 week from the date of production.The sensory evaluation was performed by 10 judges using 5-point hedonic scale to evaluatecolor, taste, acceptability, flavor, texture, spreadibility.Optimal and control sample were produced and studied in chemical, sensorial and microbiological properties during 1 (0, 7, 14, 21, 28 day) month. The results showed that the optimal sample, contain 48.95%sugar, 0.05% stevia and 2% Inulin. Sensory evaluation showed no significant difference between the optimal and control sample. Enumeration of microorganism in control and optimized samples during storage time indicated no mold and yeast. Optimal sample is the best formula from nutrition point of view and are considered as a functional food. This formulawith a reduction of more than 50% in sugar formulations and contain 2%prebiotic compound can have a positive impact on the health of consumer.Keywords: Carrot jam, Inulin, Low sugar, Prebiotics, Stevia
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Pages 203-216In this study, LDPE / Ag / Tio2 nanocomposite films were manufactured by solvent-soluble sol-gel (1% , 3% and 5% nano silver and 0.5%, 1.5% and 2.5% titanium dioxide) and then the prohibition of the growth of productive films investigated by test the inhibition zone of the bacterial indicators of Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus niger. And then the shelf life of the Sufan fish with the cover of various films produced on days 0-5-10-15 And 20 days were evaluated, and finally the presence of nano materials was confirmed by FE-SEM. The results showed that the effects of different concentrations of silver nanoparticles and titanium dioxide on growth retardation of Staphylococcus aureus, Escherichia coli 0157, Candida albicans and Aspergillus niger showed significant results (PKeywords: Nanocomposite film, Food packaging, Nanoparticles, Antibacterial properties
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Pages 217-228Flaxseed is one of the most important and most beneficial functional foods used in the industry today. In this study, the effects of flaxseed flour incorporation (at 4 levels; 5, 10, 15 and 20%) on the physicochemical (including weight loss, pH, porosity, volume, density, moisture, hardness of texture and color of crust) and sensorial properties of cupcake were studied. Data analysis showed that flaxseed flour, significantly affected the physicochemical and sensorial properties of the cake. It was discovered that by replacing wheat flour with flaxseed flour in cake formulation, weight loss, pH, porosity, volume, lightness, yellowness and sensory scores decreased and density, moisture, hardness of product texture, redness and browning index of crust increased. Above 10% of flaxseed flour incorporation, cake quality adversely affected. Thus, 5 and 10% incorporation level of flaxseed flour in cake resulted in acceptable product. Least value of weight loss (21.9%), porosity (19.2%), yellowness (27.31) and most value of density (0.57 g/cm3), darkness (39.61), redness (10.75) and browning index of cake (127.28) were related level of 20% replacing flaxseed flour.Keywords: Browning Index, Color, Cupcake, Flaxseed, Porosity
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Pages 229-241With the concern of adverse effects of lipid oxidation on food deterioration and human health, the antioxidant activity of unsaponifiable matters (USM) of hemp seed oil on soybean oil were evaluated by comparing peroxide value, carbonyl value, polar compounds and oxidative stability in thermal condition.Unsaponifiable matters of hemp seed oil was obtained 1.31% which tocopherol, strole and phenolic compounds were 178.73 mg/100g, 2779.36 mg/kg and 6832.88 mg GA/100g, respectively.The investigation results of antioxidants activity of USM using DPPH radical scavenging method, βcaroten:linoleic acid bleaching assay and ferric reduction antioxidant power showed that by increasing in USM, antioxidant activity were increased and USM in 200 ppm was similar to 100 ppm of TBHQ. In thermal conditions, control samples showed higher oxidation indexes and antioxidant activity of USM was higher than TBHQ. These results of this study suggest that USM of hemp seed oil may be used as potential source of natural antioxidant in the application of food industry to prevent lipid oxidation.Keywords: Antioxidant, Hemp seed, Unsaponifiable matters, Soybean oil
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Pages 243-252Dairy products can be a rich source of diverse lactic acid bacteria (LAB) with high functional properties, such as exopolysaccharide (EPS) production. EPS are high molecular weight polymers that are composed of sugar units and are secreted by microorganisms into the surrounding environment. Produced EPS can be used as an additive by a health effect and texturing properties. In this study, exopolysaccharide producing LAB (ropy and mucoid colonies) were isolated and identified from raw sheep milk and sheep yogurt that made in rural areas of Urmia. For this purpose, lactic acid bacteria cultured on MRS agar and M17 agar media and then isolated on the basis of the ability to produce exopolysaccharides to study the diversity of species by phenotypic methods (Gram stain, biochemical and physiological tests) and then identified by polymerase chain reaction (PCR). The 4 strains of LAB isolated were Gram-positive as well as catalase negative and were able to produce large amounts of EPS. The amounts of bonded and abandoned exopolysaccharides which measured by phenol/sulfuric acid method, were 40.28±0.2 to 65.26±0.47 mg/L and 105.68±3.2 to 136.35±0.2 mg/L, respectively. Sheep yogurt which manufactured traditionally in West Azerbaijan province, contained exopolysaccharide producing strains that can have the potential to use in the dairy industry.Keywords: Exopolysaccharide, Lactic acid bacteria, Sheep dairy products, Polymerase chain reaction
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Pages 253-263Rice bran is one of the most important byproducts of rice, which constitutes about 10 percent of riceweight and is a good source of minerals, amino acids, carbohydrates, proteins and vitamins.Because of these compounds, it is very unstable and spoilable product. In this study,phytase enzyme and dry heattreatments at to two different temperatures (110 and 120 0C) and times (10 and 20 min) were applied and experiments performed duringfour weeks storage.Measured parameters were included: ash, protein, fat, free fatty acids (FFA), peroxide value and phytic acid. In terms of the ash and protein content,the best treatment was 110 0C for 10 min.Regarding the fat content, there was no difference between treatments and raw rice bran.The lowest level of phytic acid was observed in 120 0C for 20min and the highest one was seen for the raw bran.In FFA,the minimum content was observedin 1200C for 20 min and the lowest peroxide valuewas found in 120 0Ctreatments. The results showed that addingthe enzyme and heating at 1200C lead to stabilization of rice bran and retainits nutritive value especially regarding the oil content and quality.Keywords: Phytic acid, Heating, Optimization, Rice bran, Stabilization
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Pages 265-272Sesame is a valuable oilseed. The type of black sesame seeds is a source of unsaturated fatty acids. Due to the consumption of high-fat dairy products containing high amounts of saturated fatty acids and cholesterol, it is harmful to the health of people, especially cardiovascular patients; many efforts have been made to reduce the amount of these compounds in these products. In this research, milk enrichment with flour from sesame seeds and wheat in amounts of 10, 20, 30 and 40% was added to milk and its effect on sensory and physicochemical properties during storage was investigated. Samples were stored in a refrigerator at 5 ° C and chemical tests (acid number, peroxide value and fatty acid analysis), visceral viscosity determination and sensory evaluation were performed. The results showed that increasing the percentage of sesame flour due to increased fat, acid number and peroxide value increased significantly (pKeywords: Enrichment, Unsaturated fatty acids, Flour Sesame, Milk
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Pages 273-287The design of drying equipment and plants requires the knowledge of accurate kinetic and thermodynamic properties of agricultural products. Furthermore, these properties are important for the calculation of energy requirements in drying process, the properties of adsorbed water, evaluate the microstructure of foodstuff and to study the physical phenomenon that occurs on the food surface. Since there is no report on the thermodynamic properties of dill leaves, the aim of this study was to obtain the drying curves of dill leaves, determination of the activation energy and the thermodynamic properties under different drying temperature. Color characteristic was evaluated as one important indicator of food quality and marketability. Dill leaves were dried in a hot air dryer at four temperatures (50, 60, 70,80° C) from an initial moisture content 6.185 (kg water/kg dry matter) to the moisture content 0.075 (kg water/kg dry matter). Midilli model was chosenasthe best model to describe the drying process of dill leaves. The effective diffusion coefficient of dill leaves increased with increasing drying temperature.The activation energy for leaves drying for liquid diffusion was obtained 42.29 kJmol−1. The enthalpy and entropy decreased with increasing temperature, while Gibbs free energy increased. Their values ranged between 39.35 and 39.60 kJ mol−1, between −0.3079 and −0.2927 kJ mol−1 K−1 and between 138.96 and 143.46 kJ mol−1for enthalpy, entropy and Gibbs free energy, respectively. Results of color parameters showed that drying caused a decrease in brightness, yellowness and greenness and the lowest loss of color was observed in 60°C.Keywords: Thermodynamic properties, Convective drying, Enthalpy, Entropy, Gibbs free energy, Color change, Dill leaves
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Pages 289-299White sugar is one of the most used raw materials in production of different food staffs, But researches showed thatconsumption of white sugar is related to occurrence of different diseases such as diabetes, obesity and etc. The aim of this research was to study physicochemical and antioxidant properties of nonrefined sugar-beet brown sugar produced in Iran as substitute for white sugar. For this purpose, nonrefined brown sugar samples were supplied from three large sugar factories in north-west of Iran and physicochemical properties of the samples such as total soluble solids, moisture, total ash, total hardness, sucrose content, purity, pH, protein, total phenol, total anthocyanin, antioxidant activity, apparent color and solution color were studied. White sugar was used as control. The results showed that protein, total phenol, total anthocyanin and antioxidant activity of the brown sugar samples were about 7.85 to 9.85 mg BSA/g sample, 0.55 to 0.77 mg GAE/g sample, 1.028 to 187/11.187 mg/kg sample and 4.07 to 4.46 per 10 g from kg of brown sugar solution respectively. Also, solution color and the apparent color of unrefined brown sugars were 4285.25-9399.59 ICU and 127-103 CTN respectively. It was concluded that unrefined brown sugar has higher nutrition value in comparison to white sugar.Keywords: Brown sugar, Nutrition value, Organic compounds, Sucrose
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Pages 301-311In this study, effect of carboxymethyl cellulose (CMC) gum added to batter of breaded shrimp on oil uptake, sensory characteristics and fatty acid profile were evaluated during deep-oil frying.The treatments consisted of control (without CMC), treatment A (with 2% CMC in batter), and treatment B (with 4% CMC in batter) and treatment C (with 6% CMC in batter). Result of this study indicated that adding different levels of CMC in batter, compared to control sample, was more effective in reducing of oil uptakeand retention of moisture. The effect of using different concentration of CMC in batter showed that the lowestamount of fatand maximum amount of moisture were related totreatmentsC, B,A and control, respectively.There was significantly difference between treated breaded shrimps with control one from fatty acid profiles (pKeywords: Breaded Shrimp, Deep frying, Fatty acid profile, Carboxy Methyl Cellulose
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Pages 313-322Porosity of food products during frying process is increased due to moisture removal and this phenomenon, reducesapparent density and increases oil uptake. Therefore, according to the relationship between apparent density, porosity and oil uptake, investigation of the apparent density is important. The aim of this studywas to investigate changes of apparent density and its modeling duringdeep-fat frying of potatos trips pretreated with 0.1and 0.2% carboxy methyl cellulosecon centration and 40k Hz ultrasound frequency for15 minutes. The potato strips were cut into1.2×1.2×4cm3pieces and after performing the pretreatments, the frying process was done at three different temperatures of 150,170 and 190ºC for 1, 2, 3and4 minutes. Edible coating pretreatment in both the concentration led to an increase in apparent density and this increase was not statistically significant compared to control samples (P>0.05). However, 40kHzultrasoundfrequency led to a significant decrease of the parameter in comparison with controls (PKeywords: Deep-fat frying, Modeling, Ultrasound, Edible coating, Apparent density
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Pages 323-332The aim of this research was encapsulating of Caspian Kilka fish oil and its application in cheese to produce functional product. Kilka fish is one of the most abundant and most industrial fish species in the Caspian Sea that despite its many health benefits, it has a small share of its catch for human consumption and is used most for poultry feed. The fatty acids of Kilka fish oil used in this study, in addition to having myristic (3.74±0.04), palmitic (19.97±0.06 %), palmitoleic (4.81±0.06 %), stearic (4.2±0.03 %), and linoleic fatty acids (21.67±0.05), have significant amounts of long chain fatty acids, including eicosapentaenoic acid (EPA)(6.6±0.04) and docosahexaenoic acid (DHA) (16.83±0.06).The amount of 1 and 2 percent of Kilka oil were added to the milk with the aid of the process aid and was turned to the powder using a spray dryer. Two processed cheeses were prepared by adding 5% of the produced powders. Tests of Coliform, Escherichia coli, Staphylococcus aureus Coagulase positive, Mold, Yeast and Salmonella were performed that was according to the Iranian national standard. By adding Kilka fish oil to cheese, it is possible to produce products with 0.2 ± 0.042% and 0.32 ± 0.056% EPA and 0.37 ± 0.028% and 0.66 ± 0.042% DHA which is part of the daily nutritional needs of consumers. The color and smell of functional cheeses with blank cheese were not statistically significant. However, the flavor of two types of functional cheeses with blank cheese was statistically significant, but both were in good group. In terms of general sensory evaluation, cheese samples were examined at 0, 15 and 30 days after production, which did not show any significant differences at these intervals.Keywords: Cheese, Oil, Encapsulation, Functional, Kilka
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Pages 333-343One of the ways to avoid dairy products being discontinued by people who are lactose intolerant is to make new products that are easily available. The aim of ths study was production types of low-lactose banana powder and low-lactose cocoa powder with the use of β-galactosidase enzyme using spray dryer and investigation the chemical and mcroal properties of them. The amount of moisture, protein, fat and lactose, particle size, solubility index and scorched particles of low lactose banana milk powder and low lactose cocoa milk powder were studied.Microbiological tests including aerobic mesophilic bacteria, Coliform, Escherichia coli and Staphylococcus aureus coagulase positive were also performed. About chemical characteristics moisuire content, fat and ptotein were n standard range. The results showed that 68% of powders size were between 180 to 500 µm, 30% larger than 500 µm and 2% smaller than 125 µm. Sensory evaluation was performed after the treatments were reconstituted with water.Studies have shown that low-lactose milk due to its sweet taste and banana milk and cacao milk were not desirable due to lack of sweetness (no added sugar), but low lactose banana milk had a desirable acceptance.Low lactose cocoamilk had lower scores due to taste and had significant difference with low lactose banana milk (pKeywords: Milk, Low lactose, Banana, Cocoa, Powder