Abstract:

The Longissimus dorsimuscle of Ira rabbit was used to examine variations in the lipid content and fatty acid
composition of total intramuscular lipids of Ira rabbit cooked by three different methods including stewing, microwave and
aluminum (Al) foil roasting during cold storage for 9 days. Over the whole storage period, dry weights (%) of all cooked
samples were significantly decreased (P < 0.05), especially during the late stage (from the 6th day to the 9th day). Comparing
the three cooking methods, microwave treatment had less effect on the profile of unsaturated fatty acids (UFAs), and the
resultant sample had a higher content of intramuscular lipid during the cold storage. Besides, all treated samples showed
a significant decrease in the proportion of polyunsaturated fatty acids (PUFA) but a significant increase in the proportions
of monounsaturated fatty acids (MUFA) and saturated fatty acids (SFA) throughout the entire storage period (P < 0.05).
During the last three days of storage, the PUFA profile, especially the long-chain PUFA profile, showed the most significant
decrease. Overall, the microwaved sample had higher proportion of UFA during the whole storage period. The analysis by
partial least squares regression (PLSR) suggested the microwave treatment was more conducive to reserving the composition
of intramuscular fatty acids of cooked Ira rabbit during the cold storage. However, the Al foil roasting showed no superiority
over the other two methods in maintaining the stability of the intramuscular fatty acids. Furthermore, the malondialdehyde
(MDA) accumulation in the three cooked samples was continuously increased during the cold storage. In addition, all
stewing, microwaving and Al foil-baking treatments reduced the storability greatly, as compared with the raw material, and
the thiobarbituric acid-reactive substances (TBARS) were increased rapidly during the last three days of storage.

Key words: Ira rabbit, intramuscular lipid, fatty acids, PLSR, TBARS