Practice question

Question

Freezing of 100 mm spherical meat ball with 60% moisture at 35 ᵒᶜ is being done in an air blast freezer maintained at -45 oc. Given, latent heat of fusion for water is 333.2 kJ kg ⁻¹ , the1mal conductivity of meat is 1.5 W m ⁻¹ oc ⁻¹ , convective heat transfer coefficient is 40 W m ⁻² oc ⁻¹ , density of frozen meat is 980 kg m ⁻³ and initial freezing temperature of meat ball is -10 ᵒᶜ . Using Plank's equation, Freezing Time (h) is (round off to 2 decimal places).