Heat transfer coefficients to canned green peas during end‐over‐end sterilisation

Abstract

The effect of temperature (110, 120 and 130°C), rotation speed (5, 10 and 15 r.p.m.) and headspace (4, 8 and 12 mm) on heat transfer coefficients to canned green peas during end-over-end sterilisation was studied using response surface methodology. The models developed for fluid-to-particle heat transfer coefficient, h fp , and overall heat transfer coefficient, U, were adequate, showing no significant lack of fit and satisfactory correlation coefficients. For the two responses, temperature, rotation speed and headspace have a significant effect. U, ranged between 477 and 905 W m )2°C)1 , while h fp , fluctuated between 480 and 1950 W m )2°C)1 . The highest h fp and U values are obtained at high temperatures, rotation speeds and headspaces. The verification of the prediction models was satisfactory. Dimensionless correlations were developed for h fp and U, with equations showing a good agreement with the experimental data. Heat transfer to liquids and particles was modelled using the Reynolds number, the Prandtl number and adimensional headspace.

Experimental and simulated thermal properties and process time for canned escamoles (Liometopum apiculatum) under sterilization conditions

“…With respect to heat transfer convection coefficient, significant effect of the sterilization variables was not observed. An increase of h with temperature, headspace and rotary speed has been reported in the literature when a rotary retort was used (Garrote et al, 2006). However, in this study, a stationary autoclave was used for the sterilization Table 4, it can be noticed that k and Cp values were directly proportional to the sterilization temperature, whereas the opposite effect was found for ρ, which decreased with sterilization temperature.…”

“…Thermal sterilization process has been widely used as a method of preservation for some products such as tuna fish, vegetables *Corresponding author. Email: grajales@uaslp.mx -Journal of Food, 2014http://dx.doi.org/10.1080/19476337.2014 and pates (Garrote, Silva, Roa, & Bertone, 2006;Kızıltas, Erdogdu, & Palazoglu, 2010;Plazl, Lakner, & Koloini, 2006) because the high heat destroys microorganisms and inactivates enzymes to preserve the safety and quality of the food. The heat transfer during thermal processing of a food has been directly related to the type of food and sterilization method.…”

DETERMINING CONVECTIVE HEAT TRANSFER COEFFICIENT (h) FOR HEATING AND COOLING OF BOTTLES IN WATER IMMERSION

“…Values of 1,000, 1,550 and 1,500–2,500 W/m 2 ·K are shown for water bath heating of potato cubes (Palazoglu 2006), meat (Burfoot and Self 1988) and cucumbers (Fasina and Fleming 2001), respectively, while 1,700–2,000 W/m 2 ·K‐values are shown by Simpson et al. (2008), Garrote et al. (2006) and Garrote et al.…”

Simulation of heat transfer for solid–liquid food mixtures in cans and model validation under pasteurization conditions

“…This was especially significant at the initial stages of heating to solve the momentum equations for correct velocity profiles. -Literature-reported values for thermo-physical properties (thermal conductivity, k = 0.5 W/m K; specific heat, c p = 3057 J/kg K, and density, q = 1062 kg/m 3 ) of the solid phase (peas) were used (Garrote et al, 2006(Garrote et al, , 2008 in the simulations. Since the heat transfer in peas were in conduction mode, variation in thermal diffusivity value -a ¼ k qÁcp was assumed to be negligible even though thermo-physical properties of the liquid phase were applied ad as a function of temperature as explained below.…”