The paper deals with carrot processing that combines the effect of the electric pulse loading with the lowtemperature heating. The pulse procedure was formed by one 10-ms long electric pulse (amplitude, 600 V/cm; basic frequency, 20 kHz) on the 160-ms long electric background less than 30 V/cm. The procedure was followed by the combined dynamic mechanical analysis (DMA) and dielectric thermal analysis (DETA) tests with the initial temperature of 30°C and final temperature of 90°C. Humidity in the test chamber was kept at 90 % during the whole heating test, with the heating rate of 1°C/min. During the whole test, both components of the complex modulus of elasticity (DMA) of the specimen as well as both components of the specimen's permittivity (DETA) were registered. A similar test was also performed with other specimens without the initial pulse procedure. Ratios of corresponding data (storage modulus, loss modulus, dielectric constant, and dielectric loss) are approximately constant up to the temperature of approximately 70°C where it starts to reduce substantially. The obtained results denote that can be processed using electric pulses reaching the similar state as during the tissue heating. Abbreviations A lower part of temperature scale (in our case cca 30-71°C) B higher part of the temperature range (in our case cca 71-90°C) B1 lower part of B (in our case approximately 71-80°C) B2 higher part of B (in our case approximately 80-90°C) CV (%) coefficient of variations DETA dielectric thermal analysis DL (−) or (%)dielectric loss (imaginary part of relative permittivity) DMA dynamic mechanical analysis DP (−) or (%) dielectric constant (real part of relative permittivity) E (V/cm) maximal intensity of the pulse electric field E 0 (V/cm) intensity of electric field-parameter of Eq.(2) IQR interquartile range Q3-Q1 K (cm/V) intensity of specimen impedance to pulse field (Eq. (2)) LM (Pa) or (%) loss modulus MV mean value Q1 first quartile Q2 second quartile R (−) ratio of Z x and Z i SM (Pa) or (%) storage modulus SE standard error SD standard deviation T (°C) temperature tg (−) symbol for loss tangent (in both DEA and DETA) X t (Ω) v a l u eo fZ x at infinite E

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A b s t r a c t. Specimens prepared from yacon roots in first two weeks after harvest were tested by dynamic mechanical analysis thermal analysis at temperatures between 30 and 90°C. No differences between different parts of roots were proved. There were indicated some differences in the test parameters that were caused by short time storage of the roots. One source of the differences was loss of water during the roots storage. The measured modulus increased during short time storage. Detailed study of changes of the modulus during the specimen dynamic mechanical analysis test provided information about different development of the storage and loss moduli during the specimen heating. The observed results can be caused by changes in cellular membranes observed earlier during vegetable heating, and by composition changes due to less stable components of yacon like inulin.K e y w o r d s: yacon, storage, inulin, stability, dynamic mechanical analysis