Formulation and characterization of food simulants for cooling and freezing appliances

Baydemir, Seçil
Electrical household and similar cooling and freezing appliance manufacturers are continuously seeking ways to improve properties of their products. To design such appliances and obtain generalized and standardized results, developing test methods using food simulants has been a new strategy. Drip loss is an important problem experienced by the consumers during thawing of meat and refrigerator manufacturers try to design appliances to minimize this problem. Food simulants are used to mimic the cooling and freezing responses of foods during thawing and quick freezing. In this study, different food simulants for ‘drip loss’ were developed by using different hydrocolloids such as corn starch (10%, 15%, 20%), curdlan (3%), agar (2%, 3% and 4%) and methylcellulose (5%). During freeze-thaw cycle, food simulants along with ‘real foods’ (sirloin and chicken breast) were stored at two different temperatures (-18oC and -27oC) for 20 h and thawed at room temperature for 4 h. For characterization of the food simulants, total drip loss, hardness, FT temperature cycle, water holding capacity (WHC), NMR and scanning electron microscopy (SEM) measurements were conducted. To observe how water distribution changed, all measurements were conducted before and after FT cycle. Total drip loss of real food samples was also measured to compare with food simulants throughout thawing process. There were significant differences in drip loss rates for both curdlan-based food and methyl cellulose-based simulants frozen at two different temperatures (p<0.05). According to NMR analysis, curdlan-based samples with the lowest concentration had highest T2 values before FT cycle. It was observed that these samples also had the highest total drip loss percentage after FT cycle. Moreover, total drip loss (%) was observed to be positively correlated with spin-spin (T2) relaxation times before FT cycle (r= 0.844, p<0.05). After FT cycle, there was an increase in hardness values of curdlan-based food simulants while there was a decrease in methyl cellulose-based ones. SEM images showed that the addition of secondary polysaccharide with different concentration levels to methylcellulose-based and curdlan-based food simulants affected the microstructures of hydrogel. Home appliances manufacturers should develop test methods with standard artificial materials, which are food simulants, to measure the freezing performance of their products. Food simulants formulated and characterized in this study can be used in the design of freezer systems.


Design of a mixer for uniform heating of particulate solids in microwave ovens
Çevik, Mete; Esin, Ali; Department of Food Engineering (2011)
The aim of this study is to design a mixer with appropriate parts for uniform treatment of the material in household microwave ovens which can not be achieved with the turntable. The designed mixer’s performance was tested by the help of color and surface temperature values. In the design of the mixer primarily mixing in the vertical and radial directions were sought and for this purpose blades and wings for directing the material especially in these directions were present. The rotational motion of the mix...
Condensation modeling on the fin top of a micro-grooved heat pipe
Alipour, Mobin; Dursunkaya, Zafer (null; 2017-06-01)
Heat pipes are used as an alternative to forced cooling systems, especially for cooling current electronic devices which contain concentrated hot spots. Condensation occurs on the top of the fins and approximations to estimate the condensing mass is used in literature. In this study, four different approaches to condensation modeling in micro-grooved heat pipes are discussed. The effect of disjoining pressure, the reverse angles and temperature differences are studied.
Simulation of refrigerated space with radiation
Bayer, Özgür; Oskay, Rüknettin; Department of Mechanical Engineering (2009)
Performance of a refrigerator can be characterized with its ability to maintain a preset low temperature by spending the least amount of electricity. It is important to understand natural convection inside a refrigerator for optimizing its design for performance. Computational Fluid Dynamics (CFD) together with experiments is a very powerful tool for visualizing flow and temperature fields that are essential for understanding a phenomenon that involves both fluid and heat flow. In this aspect, simulations a...
Comparison and modeling of microwave tempering and infrared assisted microwave tempering of frozen potato puree
Seyhun, N.; Ramaswamy, H.; Şümnü, Servet Gülüm; Şahin, Serpil; Ahmed, J. (Elsevier BV, 2009-06-01)
Microwave tempering and infrared assisted microwave tempering of frozen foods were simulated by using finite difference method. The effects of microwave power and infrared power on tempering were discussed. Three different microwave power levels (30%, 40%, and 50%) and three different infrared power levels (10%, 20%, and 30%) were used. The increase in microwave power level and infrared power level decreased tempering times. The change of heat capacity and the dielectric properties of frozen potato puree wi...
Atay, Atakan; Sariarslan, Busra; Kuscu, Yigit F.; Saygan, Samet; Akkus, Yigit; Gurer, A. Turker; Cetin, Barbaros; Dursunkaya, Zafer (2019-01-01)
Heat pipes are widely used in thermal management of high heat flux devices due to their ability of removing high heat loads with small temperature differences. While the thermal conductivity of standard metal coolers is approximately 100-500 W/m.K, effective thermal conductivities of heat pipes, which utilize phase-change heat transfer, can reach up to 50,000 W/m.K. In industrial applications, commercially available heat pipes are commonly preferred by thermal engineers due to their low cost and versatility...
Citation Formats
S. Baydemir, “Formulation and characterization of food simulants for cooling and freezing appliances,” M.S. - Master of Science, Middle East Technical University, 2022.