Table 1.

Comparison of different freeze-thaw methods for extracting of C-PC.

Protocol	Primary freezing	Intermediary freezing	Extended freezing	Thawing
1	—	−5 °C, 90 min	−20 °C, 3 h	+35 °C, 1 h
2	−20 °C, 10 min	−5 °C, 1 h	−20 °C, 3 h	+35 °C, 1 h
3	−20 °C, 2 min	−5 °C, 1 h	−20 °C, 3 h	+35 °C, 1 h
4	Liquid nitrogen, 2 min	−5 °C, 1 h	−20 °C, 3 h	+35 °C, 1 h
5	—	—	−70 °C, 4 h	+4 °C, 4 h
6	—	—	−20 °C, 4 h	+4 °C, 4 h