Effect of freezing and blanching on quality traits of carrot (Daucus carota L.)

The investigations were carried out to study the effect of individual quick freezing (IQF) and conventional freezing (CF), with treatments viz. hot water blanching (HWB), steam blanching (SB) and hot water blanching (HWB) after potassium meta bisulphite treatment on quality traits of carrots (Daucus carota L.). The quality of carrot cubes was assessed by judging colour, texture, moisture, sensory evaluation and β-carotene. Pre-treatment hot water blanching gave best results for L (34.6), b (4.8), ΔE (0.24) variable and hue angle (13.68) whereas, hot water blanching after chemical treatment gave best results for ‘a’ (20.6) and chroma value (21.22) and the steam blanching was found to be most optimum for texture (46.42 kg-f), β-carotene (9.25 mg/100g), moisture content (721.62%) and sensory evaluation (91.67). After freezing of the treated carrots, the colour parameters gave best results under IQF and HWB with ‘L’ (34.7), ‘a’ (20.4), ‘b’ (5.0) and ‘ΔE’ (0.49) indicating that darker and reddish coloured samples underwent minimum change in colour after freezing. The interaction of IQF and SB gave best results for texture (59.40 kg-f), moisture content (700.31% on d.b) and organoleptic evaluation (94.44). The beta-carotene with content of 9.21 mg/100g was found to be maximum with CF and SB methods.