نوع مقاله : مقاله پژوهشی

نویسندگان

گروه علوم و صنایع غذایی، دانشگاه منابع طبیعی گرگان.

چکیده

در این پژوهش، انتقال حرارت و جرم در فرآیند سرخ‌کردن به‌طور جامعی مورد بررسی قرار گرفت. برای این منظور، عملیات سرخ کردن خلال سیب زمینی در یک سرخ‌کن مجهز به سیستم ترموکنترلر با ترموکوپل نوع K، در سه دمای مختلف روغن 145، 160 و °C 175 به مدت60، 120، 180 و 240 ثانیه انجام گرفت. تغییرات دمای مرکزی محصول طی سرخ کردن با استفاده از ترموکوپل نوع T متصل به دستگاه ثبت داده در کامپیوتر ثبت گردید. محتوی رطوبت و روغن نمونه ها نیز در هر زمان و دمای فرآیند اندازه گیری شد. پارامترهای انتقال حرارت و جرم با استفاده از نمودارهای نسبت‌های دمایی و غلظت بدون بُعد و معادلات تجربی با هدف توسعه روشی واقع بینانه در تخمین، برآورد شد. نتایج نشان داد، عدد بایوت انتقال جرم (Bim)، ضریب انتقال جرم و نفوذ موثر رطوبت با افزایش دمای روغن به‌طور معنی‌داری زیاد شد. در مدل های رگرسیونی، با افزایش دمای بستر فرآیند محتوی تعادلی روغن در زمان بی نهایت کاهش یافت و می توان گفت با افزایش دما، جذب روغن کاهش می یابد. از طرفی ارتباط خطی بین ثابت‌های سنتیک کاهش آب و جذب روغن مشاهده شد که تائید کننده تاثیر پیش تیمار خشک کردن جزئی در کاهش ثابت سنتیک جذب روغن نیز است. این تاثیر می تواند به دلیل فشردگی ماتریس ماده غذایی و در نتیجه کاهش نفوذ روغن بعد از خروج از سرخ کن طی سرد شدن باشد. در نهایت، با افزایش دمای فرآیند نیز عدد بایوت انتقال حرارت (Bih)، ضریب انتقال حرارت جابجایی و هدایت حرارتی محصول به‌طور معنی داری کاهش یافت.

کلیدواژه‌ها

Ahromrit, A., and Nema, P.K., 2010, Heat and mass transfer in deep-frying of pumpkin, sweet potato and taro. Journal of Food Science and Technology, 47, 632-637.
Alvis, A., Velez, C., Rada-Mendoza, M., Villamiel, M., and Villada H.S., 2009, Heat transfer coefficient during deep-fat frying. Food Control, 20, 321-325.
Andres, A., Arguelles, A., Castello, M.L., and Heredia, A., 2012, Mass transfer and volume changes in French fries during air frying. Journal of Food and Bioprocess Technology, Doi: 10.1007/s11947-012-0861-2.
AOAC, 2000, Official methods of analysis. 17th ed., Association of Official Analytical Chemists. Washington, DC, Unites States.
Baik, O.D., and Mittal, G.S., 2005, Heat and moisture transfer and shrinkage simulation of deep-fat tofu frying, Food Research International, 38, 183-191.
Blumenthal, M.M. and Stier, R.F., 1991, Optimization of deep-fat frying operations, Trends in Food Science and Technology, 2, 144-148.
Budzaki, S. and Seruga, B., 2004, Determination of convective heat transfer coefficient during frying of potato dough. Journal of Food Engineering. Journal of Food Engineering, 66, 307-314.
Costa, R.M., Oliveira, F.A.R., Delaney, O., and Gekas, V., 1999, Analysis of the heat transfer coefficient during potato frying. Journal of Food Engineering, 39, 293-299.
Debnath, S., Bhat, K.K., and Rastogi, N.K., 2003, Effect of pre-drying on kinetics of moisture loss and oil uptake during deep fat frying of chickpea flour-based snack food. Lebensm.-Wiss. U.-Technol, 36, 91-98.
Dincer, I., 1996. Modelling for heat and mass transfer parameters in deep frying of products. Heat and Mass Transfer, 32, 109-113.
Duran, M., Pedreschi, F., Moyano, P., and Troncoso, E., 2007, Oil partition in pre-treated potato slices during frying and cooling. Journal of Food Engineering, 81, 257-265.
Farid, M.M., and Chen X.D., 1998, the analysis of heat and mass transfer during frying of food using a moving boundary solution procedure. Journal of Heat and mass transfer, 34, 69-77.
Farinu, A. and Baik, O.-D., 2008, Convective mass transfer coefficients in finite element simulations of deep fat frying of sweetpotato. Journal of Food Engineering, 89,187-194.
Farinu, A., and Baik, O. D., 2007, Heat transfer coefficients during deep fat frying of sweetpotato: Effects of product size and oil temperature, Food Research International, 40, 989-994.
Farkas, B.E., Sing R.P., and Rumsey T.R., 1996, Modelling heat and mass transfer in immersion frying. I, Model development. Journal of Food Engineering, 29, 211-226.
Gupta, P., Shivhare, U.S. and Bawa, A.S., 2000, Studies on frying kinetics and quality of French fries. Drying Technology, 18, 311-321.
Kita, A., Lisińska, G., and Gołubowska, G., 2007, The effects of oils and frying temperatures on the texture and fat content of potato crisps. Food Chemistry, 102, 1-5.
Krokida, M.K., Oreopoulou, V., and Maroulis, Z.B., 2000, Water loss and oil uptake as a function of frying time, Journal of Food Engineering, 44, 39-46.
Krokida, M.K., Oreopoulou, V., Maroulis, Z.B., and Marinos-Kouris, D., 2001, Effects of pre-drying on quality of French fries. Journal of Food Engineering, 49, 347-354.
Loon, W.A.M.V., Visser, J.E., Linssen, J.P.H., Somsen, D.J., Klok, H.J., and Voragen, A.G.J., 2007, Effect of pre-drying and par-frying conditions on the crispness of French fries. European Food Research and Technology. 225, 929-935.
Mohebbi, M., Fathi, M., and Shahidi, F., 2011, Genetic algorithm artificial neural network modeling of moisture and oil content of pretreated fried mushroom. Food and Bioprocess Technology, 4, 603-609.
Moyano, P.C., and Pedreschi, F., 2006, Kinetics of oil uptake during frying of potato slices: Effect of pre-treatments. LWT - Food Science and Technology, 39, 285-291.
Palaniappan, S., and Sizer, C. E., 1997, Aseptic process validated for foods containing particulates. Food Technology, 51, 60-68.
Parkash, S., and Gertz, C., 2004, New theoretical and practical aspects of the frying Process, European Journal of Lipid Science and Technology, 106, 722-727.
Pedreschi, F., Hernandez, P., Figueroa, C., and Moyano, P.C., 2005, modeling water loss during frying of potato slices. International Journal of Food Properties, 8, 289-299.
Razavi, M., and Akbari, R., 2006, Biophysical properties of agricultural and food materials. Ferdosi university of Mashhad publication, pp. 255-256.
Romani, S., Bacchiocca, M., Rocculi, P., and Rosa, M.D., 2008, Effect of frying time on acrylamide content and quality aspects of French fries. European Food Research and Technology, 226, 556-560.
Sabbaghi, H., Ziaiifar, A. M., Sadeghi Mahoonak, A., Kashaninejad, M., and Mirzaei, H., 2015, Evaluation of mathematical models to describe the effect of temperature. Iranian Journal of Biosystems Engineering, 46(2), 135-145.
Sabbaghi, H., Ziaiifar, A .M. Sadeghi Mahoonak, A., kashaninejad, M., and Mirzaei, H., 2014, Estimation of convective heat transfer coefficient as function of the water loss rate during frying process. Iranian Food Science and Technology Research Journal, 1394(11), 473-484. doi:10.22067/ifstrj.v1394i11.29653
Sahin, S., Sastry, S.K., and Bayindirli, L., 1999, the determination of convective heat transfer coefficient during frying, Journal of Food Engineering, 39, 307-311.
Saravacos, G. D. and Maroulis, Z. B., 2001, Transport Properties of Foods. Marcel Dekker, New York.
Singh, R.P., and Heldman, D.R., 2001, Introduction to food engineering, (3rd Ed.). London, UK: Academic Press.
Taler, J., 2014, Superposition method for multidimensional heat conduction problems, Hetnarski, R. B. (Ed.), Encyclopedia of Thermal Stresses, Springer Netherlands, pp. 4708-4718.
Treybal, R.E., 1995, Mass-transfer operations, (3rd Ed.), McGraw Hill Publication. USA.
Troncoso, E., and Pedreschi, F., 2009, Modeling water loss and oil uptake during vacuum frying of pre-treated potato slices. LWT-Food Science and Technology, 42, 1164-1173.
Ufheil, G., and Escher, F., 1996, Dynamics of oil uptake during deep-fat frying of potato slices, Lebensmittel-Wissenschaft and Technologie. 29, 640-644.
Vitrac, O., Dufour, D., Trystram, G. and Raoult-Wack, A.L., 2002, Characterization of heat and mass transfer during deep-fat frying and its effect on cassava chip quality. Journal of Food Engineering, 53, 161-176.
Wang, N., and Brennan, J.G., 1992, Thermal conductivity of potato as a function of moisture content, Journal of Food Engineering, 17, 153-160.
Yildiz, A., Palazoglu, K., and Erdogdu, F., 2007, Determination of heat and mass transfer parameters during frying of potato slices. Journal of Food Engineering, 79, 11-17.
Zheleva, I., and Kamburova, V., 2009, modeling of heating during food processing. Costa, R., and Kristbergsson, K. (Eds.), Predictive modeling and risk assessment, Springer US, pp. 79-99.
Ziaiifar, A.M., Heyd, B., and Courtois, F., 2009, Investigation of effective thermal conductivity kinetics of crust and core regions of potato during deep-fat frying using a modified Lees method. Journal of Food Engineering, 95, 373-378
CAPTCHA Image