Abstract
Solutions of low density lipoprotein fraction (LDF) of yolk were frozen at -18°C for 20 hr, and relative turbidity of the thawed solution was measured. Almost no change of relative turbidity was observed in the presence of salts showing lower eutectic temperature than freezing temperature, except salts generating the turbidity change of the protein solution even at more than 4°C and organic acid salts. When LDF solutions containing various amounts of KCl or NaCl were frozen at lower and higher temperatures than their eutectic temperatures, both viscosity and relative turbidity of thawed solution markedly increased only in the case of freezing at the lower temperatures. From the experimental results it was discussed that the progressive removal of water during freezing could give a harmful effect on low density lipoprotein.
