Effect of cryogenic freezing on the rheological and calorimetric properties of pasteurized liquid egg yolk

Abstract

The egg yolk undergoes an irreversible gelation process when freezing to –6 °C or lower. In this experiment, liquid egg yolk (LEY) was frozen in liquid nitrogen and stored at –18 °C for 150 days. The measurement of pH and colour of LEY were performed. The examination of the rheological and calorimetric properties of samples was also carried out. The results indicated that the pH of LEY changed significantly during frozen storage, increasing from 6.37 ± 0.02 to 6.58 ± 0.03 over five months. The colour of the samples also showed a significant change compared to the fresh sample. The rheological properties of the LEY also changed significantly after 1 day of freezing and during frozen storage, with a clear increasing trend of the yield stress. The results of the calorimetric study showed that freezing and frozen storage did not affect the denaturation temperature, however, the denaturation enthalpy was reduced by about half after five months of frozen storage.

Investigation of the effects of bovine collagen peptides and mixed berries on rheological properties and biological activity of egg white-based beverage via central composite design

“…The samples after heat treatment and cooling period showed smoothie-like or yogurt beverage-like consistency depending on the mixed berries' concentration, so their rheological properties were analyzed by Anton Paar MCR 92 rheometer (Anton Paar, France) in rotational mode equipped with a concentric cylinder (CC27) similar to Hidas et al ( 57 ). Anton Paar RheoCompass software (v 1.21.852) was used to control the measurements.…”

The Effect of Microbial Transglutaminase on the Viscosity and Protein Network of Kefir Made from Cow, Goat, or Donkey Milk

“…For the analyses of the rheological properties of the final kefir samples, 15 mL samples from the designated containers were placed in the sample holder of an Anton Paar (France) MCR 92 rheometer. The shear stress values of the samples were investigated using a CC27 system between 10 and 1000 1/s shear rate, similar to [14], at 15 • C. The Herschel-Bulkley model was used to analyze the flow curves (shear rate-shear stress diagrams). This model was used to describe the rheological properties of samples at 15 • C. Most of the R 2 values of the fitted model were higher than 0.99.…”