Studies on Freeze‐thaw Celation of Very Low Density Lipoprotein From Hen's Egg Yolk

The disruption of lipid‐protein complexes in egg yolk very low density lipoprotein (VLDL) during freezing and thawing was studied chemically and morphologically. Upon rapid freezing and thawing, the gelation did not occur and VLDL particles only clustered. Nevertheless, some of the VLDL constituents were liberated from particles. On either slow freezing or slow thawing, the aggregation was complete and the gelation occured. Also in this case, VLDL fragments were liberated. The liberated fraction was rich in protein and phospholipids which surround the neutral lipid core. Thus, on freezing and thawing, the disruption of the surface that stabilizes the particulate nature of VLDL initially occurs. In conclusion, the gelation might be attributed to the aggregation of disrupted VLDL particles which finally induces the formation of a mesh‐type structure.