Initial freezing points Ti of egg samples (melange of egg yolk and white, egg yolk, egg white) and surimi mixed with different mass fractions of . -carrageenan (w = 1O10%), NaCl (w = 1O10%), and mixtures of NaCl and . -carrageenan in mass ratio of 4:1 (w = 1O10%) were determined by use of differential thermal analysis (DTA). Samples of surimi were prepeared in laboratory conditions from Sardina pilchardus. Water content in surimi was 81.50%, in egg yolk 47.65%, in egg white 88.1%, and in melange it was 64.41% before mixing with the added substances. Relations between decrease of the initial freezing point Ti as function of mass fractions w of the added substances were determined by linear regression. Coefficients of determination in range of R 2 = 0.94O0.98 for samples of surimi, and R 2 = 0.92O0.98 for samples of egg were obtained. The largest effect of cryoscopic depression on initial freezing point Ti were exhibited by the samples of surimi with added: a) NaCl in the temperature range from O0.19 to O11.11 °C, b) mixtures of NaCl and . -carrageenan (from O0.19 to O9.08 °C), and c) . -carrageenan (from O0.19 to O0.72 °C). For the samples with pure NaCl the largest decrease of Ti was obtained for: a) egg yolk (from O0.59 to O20.77 °C), b) melange (from O0.59 to O8.74 °C), and c) egg white (from O0.50 to O7.37 °C). The results are compared and discussed with Chang-Tao model for prediction of Ti for meat.
Kovačević, D. & Kurtanjek, Ž. (1993): Odredivanje entalpije smrznutog iskoštenog ribljeg mesa (surimija) diferencijalnom termickom analizom. (Enthalpy determination of frozen surimi by differential thermal analysis.) Prehrambeno-tehnol. biotehnol. rev., 31, 157-164.