Technical note: loss of nitrate from carrots during blanching

Loss of nitrate from carrots during blanching was studied using several parameters, such as temperature of water, thickness of carrot slices, and volume ratio of carrots and water. It was found that the kinetics of nitrate diffusion fitted well to the Fick's general diffusion equation. Surface mass transfer coefficient (K) was related to temperature by an Arrhenius type reaction. The values of activation energy (Ea) and the constant K0 were calculated as 74 kJ/mole and 2769 × 103 kg/m2/sec. As expected the initial rates of diffusion were proportional to carrot surface and the efficiency of nitrate removal decreased with increasing blancher load. The proposed model may be used to determine the optimum blanching conditions of carrots in the baby food industry.