Effect of preheating and calcium pre-treatment on pectin structure and thermal texture degradation: a case study on carrots

Abstract In this work, the thermal texture degradation of carrots was studied on a kinetic basis. The influence of preheating and/or calcium pre-treatment on thermal texture degradation was investigated. Carrots were preheated for 20, 30 and 40 min at 50, 60 and 70 °C and/or soaked in 0.5% CaCl 2 -solution for 1 h. After the pre-treatment, the texture degradation was investigated at 90 and 100 °C. The texture was determined objectively with a texture analyser. Kinetic parameters ( k and TP ∝ /TP 0 ) were estimated using a fractional conversion model. Next, it was tried to relate the texture degradation with the degree of esterification of the pectins. It was concluded that in addition to the degree of esterification other parameters will be needed to better understand and explain the texture improvement after preheating.

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