Alive hard shell mud crabs (S. serrata) and soft shell mud crabs
with an average weight ranging from 150 to 180 g were purchased
from a farm in Kantang, Trang, Thailand. Soft shell mud crabs were
obtained 24 h after molting. The crabs were kept in the plastic
basket covered with wet cloth to keep the crabs moist. All samples
were transported to the Department of Food Technology, Prince of
Songkla University, Hat Yai, Songkhla, Thailand within 3 h. Crabs
were washed with running water and subjected to analyses and
freezing. Prior to analyses, the initial fresh samples and subsequent
frozen samples were excised and meat was collected, chopped
finely and pooled as the composite sample. For frozen samples, the
samples (8 crabs) were randomly taken and thawed using running
water until the core temperature reached 0–2 C. Three different
lots with total 192 crabs for each type of crab (64 crabs for each lot
of one type of crab) were employed for the whole study.