مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

بررسی تاثیر شار حرارتی پله ای صعودی بر میزان تخلخل و روشنایی نان مسطح پخته شده به روش آزمایشگاهی و عددی

نوع مقاله : پژوهشی اصیل

نویسندگان
هادی افکار 1
علی کیانی فر 1
حسین زمانی 2
1 گروه مهندسی مکانیک، دانشگاه فردوسی مشهد
2 طراحی ماشین آلات صنایع غذایی، موسسه پژوهشی علوم و صنایع غذایی
چکیده
نان مسطح( نان با ضخامت کم و سطح صاف) بر خلاف نان حجیم در کشورهای اندکی از جمله ایران مورد استفاده قرار می­گیرد و تحقیقات بسیار کمی درباره آن انجام شده است. هدف از انجام این پژوهش، بررسی عددی و آزمایشگاهی میزان تخلخل و روشنایی سطح در نان مسطح پخته شده با پروفیل­های مختلف شار حرارتی پله­ای صعودی می­باشد. در این پژوهش، به منظور بررسی اثر پروفیل­های مختلف شار حرارتی در فرایند پخت نان مسطح متخلخل، نان­های مورد نیاز با استفاده از دستگاه ساخته شده در مقیاس آزمایشگاهی پخته شده و معادلات انتقال گرما، جرم، تخلخل و روشنایی به صورت عددی با استفاده از روش تفاضل محدود در نرم افزار مطلب مدل­سازی شده­اند. نتایج نشان داد که مقادیر آزمایشگاهی و عددی مطابقت خوبی با یکدیگر دارند. سه پروفیل شار حرارتی پله­ای صعودی با گام­های زمانی مختلف به صورت آزمایشگاهی و عددی مورد بررسی قرار گرفتند. نتایج تجربی نشان دادند که وضعیت تخلخل نان پخته شده با پروفیل شار حرارتی صعودی با چهار پله، منظم­تر و میانگین مقادیر قطر و مساحت منافذ در تصاویر حاصل از عکس [1]SEM نسبت به پروفیل­های مورد بررسی دیگر بیشتر می­باشد. همچنین با توجه به نتایج تجربی و عددی مشاهده شد پارامتر مربوط به روشنایی سطح نان( L* ) برای نان پخته شده با پروفیل شار حرارتی صعودی با چهار پله در محدوده مناسب می باشد.


[1] میکروسکوپ الکترونی روبشی
کلیدواژه‌ها
انتقال گرما و جرم
نان مسطح متخلخل
شار حرارتی صعودی پله ای
تفاضل محدود
روشنایی نان

موضوعات

عنوان مقاله English

experimental and Numerical investigation of effect of ascending step heat flux on porosity and brightness of baked bread

نویسندگان English

Hadi Afkar 1
ali kianifar 1
Hosein zamani 2
1 Department of Mechanical Engineering, Ferdowsi University of Mashhad
2 Department of Food Industry Machineries , Research Institute of Food Science & Technology
چکیده English

Flatbreads have a small thickness and flat surface and, unlike bulk breads, are only used in few countries such as Iran. Given the lack of research on this type of bread, the objective of this study was to numerically and experimentally investigate the porosity and surface brightness of flatbreads baked under different ascending step heat flux profiles. In order to investigate the effect of different heat flux profiles on the baking process of porous flatbread, the required breads were baked in a laboratory-scale device and the equations of heat and mass transfer, porosity, and brightness were numerically modeled using the finite difference method in MATLAB. The results showed were suggestive of the good consistency between the experimental and numerical values. A total of 3 ascending step heat flux profiles with different time steps was experimentally and numerically investigated. The results also showed that the porosity of the bread baked under an ascending heat flux profile with 4 steps was more regular and that the average diameter and area of porosities obtained from the SEM imaging were higher in this profile compared to the other profiles. Moreover, based on the experimental and numerical results, the surface bright parameter (L*) was within the appropriate range for the breads baked under the ascending heat flux profile with 4 steps.

کلیدواژه‌ها English

Heat and mass transfer
Porous flat bread
ascending step heat flux
Finite Difference
Lighting bread
1. Jefferson, D.R., Lacey, A.A., Sadd, P.A. Crust density in bread baking: mathematical modelling and numerical solutions. Applied Mathematical Modelling. 2007 :31 (2), 209–225.
2.Chiotellis, E., Campbell, G.M.aProving of bread dough I: modelling the evolution of the bubble size distribution. Food Bioprod. Process. 2003, 81, 194–206.
3.Bellido, G.G., Scanlon, M.G., Sapirstein, H.D., Page, J.H. Use of a pressuremeter to measure the kinetics of carbon dioxide evolution in chemically leavened wheat flour dough. J. Agric. Food Chem. 2008, 56, 9855–9861.
4.Bellido, G.G., Scanlon, M.G., Page, J.H. Measurement of dough specific volume in chemically leavened dough systems. J. Cereal Sci. 2009 49, 212–218.
5.Salagnac, P., Glouannec, P., Lecharpentier, D. Numerical modeling of heat and mass transfer in porous medium during combined hot air, infrared and microwaves drying. Int. J. Heat Mass Transf. 2004, 47, 4479–4489.
6.Wagner, M.J., Lucas, T., Le Ray, D., Trystram, G. Water transport in bread during baking. J. Food Eng. 2007, 78, 1167–1173.
7. Jefferson, D.R., Lacey, A.A., Sadd, P.A. Understanding crust formation during baking. Journal of Food Engineering. 2006, 75 (4), 515– 521.
8. Mondal, A., Datta, A.K. Bread baking – a review. J. Food Eng. 2008, 86, 465–474.
9. Andersson, R., Ha¨ma¨la¨inen, M., Aman, P. Predictive modelling of the bread-making performance and dough properties of wheat. Journal of Cereal Science. 1994, 20 (2), 129–138.
10. Andersson,Ahrne, L., C., Floberg, P., Rosen, J., Lingnert, H. Effect of crust temperature and water content on acrylamide formation during baking of white bread: steam and falling temperature baking. LWT – Food Science and Technology. 2007, 40 (10), 1708–1715.
11. Purlis, E., Salvadori, V.O. A moving boundary problem in a food material undergoing volume change simulation of bread baking. Food Res. Int. 2010, 43, 949–958.
12. de Vries, U., Sluimer, P., & Blocksma, A. H. , A quantitative model for heat transport in dough and crumb during baking. Cereal Science and Technology in Sweden (pp. 174±188). Lund University Chemical Centre ,1998.
13. Thorvaldsson, K., Janestad, H. , A Model For Simultaneous Heat, Water and Vapour Diffusion , Journal of Food Engineering. 1999, 40, Pg.167-172.
14. Broyart, B. , G. Trystram, Modelling of heat and mass transfer phenomena and quality changes during continuous biscuit baking using both deductive and inductive (neural network) modelling principles, Institution of Chemical Engineers. 2003, Vol 81, Part C.
15. Ashim K. Datta, Serpil Sahin, Gu¨lu¨m Sumnu, S. Ozge Keskin . Porous media characterization of breads baked using novel heating modes. Journal of Food Engineering. 2007 , 79 ,106–116.
16.Wahlby, U., Skjoldebrand, C. Reheating characteristics of crust formed on buns, and crust formation. Journal of Food Engineering. 2002, 53 (2), 177–184.
17. Zanoni, B. , Peri, C. , A Study Of The Bread Baking Process I: A Phenomenological Model, Journal Of Food Engineering. 1993,19, Pg.389-398.
18. Nicolas, V., Salagnac, P., Glouannec, P.,. Ploteau, J.-P., Jury, V, Boillereaux, L.2014. Modelling heat and mass transfer in deformable porous media:Application to bread baking. Journal of Food Engineering. 2014, (130) 23–35.
19.Datta, A. K., & Anantheswaran, R. C. Handbook of microwave technology for food applications. New York: Marcel Dekker.2001
20.Fan, J. T., Mitchell, J. R., & Blanshard, J. M. V. A model for the oven rise of dough during baking. Journal of Food Engineering.1999, 41, 69–77.
21.Hong, S.-W., Yan, Z. Y., Otterburn, M. S., & McCarthy, M. J. Magnetic resonance imaging (MRI) of a cookie in comparison with time-lapse photographic analysis (TLPA) during baking process. Magnetic Resonance Imaging. 2007, 14(7/8), 923–927.
22. Mondal, A., Datta, A.K. Two-dimensional CFD modeling and simulation of crustless bread baking process. Journal of Food Engineering 99 .2010. 166–174.
23. Davide Papasidero, Sauro Pierucci, Flavio Manenti . Energy optimization of bread baking process undergoing quality. Energy 2016: 116 , 1417e1422.
24. VasudhaSharma, AasthaBhardwaj. Scanning electron microscopy (SEM) in food quality evaluation. Woodhead Publishing Series in Food Science, Technology and Nutrition
2019: Pages 743-761
مهندسی مکانیک مدرس
دوره 21، شماره 6
خرداد 1400
صفحه 367-378