The role of the glass transition temperature of the maximally-freeze-concentrated phase in the storage stability of frozen escamoles (Liometopum apiculatum M.) [El rol de la temperatura de transición vítrea de la fase máximamente crio-concentrada sobre la estabilidad de escamoles congelados (Liometopum apiculatum m.)] Article uri icon


  • The objective of this research was to measure the freezing curve and the parameters of the maximally-freeze-concentrated phase of escamoles and to propose their use in preventing chemical and structural changes during frozen storage. Samples with freezable and unfreezable moisture were prepared and analyzed with differential scanning calorimetry (DSC), with which freezing points (Tm, T′m) and glass transition temperatures (Tg, Tg′) were determined. An average Tg value of 61.5 ± 6.4 ºC was found for anhydrous escamoles. Samples containing unfreezable water, however, showed no glass transition. The maximalfreeze-concentration condition was determined at the values of x′ s = 0.870 g solid/g sample, T′m =-22.7 °C and T′g = -30.7 °C. The stability of frozen escamoles was tested based on the application of their corresponding T0 g value. Therefore, escamoles were frozen at -20, -35 and -80 °C for four months, and quality parameters such as thawing loss, protein and lipid oxidation and structural changes in thawed escamoles were evaluated. Results (p < 0.05) showed that chemical and structural changes were mainly detected in samples stored at -20 °C. Thus, a storage temperature of -35 °C is recommended for the long-term stability of fresh escamoles. © 2018, Universidad Autonoma Metropolitana Iztapalapa. All rights reserved.

publication date

  • 2018-01-01