## 3 Results and Discussion
### Free Amino Acids (FAAs)  
It is well known that certain amino acids play an essential role in establishing the flavor profile of foods, some contributing distinct flavor characteristics and others serving as precursors for odors and other flavor compounds [33]. As depicted in Table 2, there existed a statistically significant difference (\(p<0.05\)) in the composition of FAAs across different heat treatments applied to SEY. This disparity can likely be attributed to variations in moisture loss caused by various cooking methods during processing. Glutamic acid (Glu) was the most abundant amino acid of the three samples, and it, along with aspartic acid (Asp), had a pleasant fresh taste, often contributing greatly to umami [34]. The ratio of umami amino acids (Glu and Asp) to total amino acids was also consistent with the result of umami by E-tongue analysis. In addition, the synergistic effect between alanine (Ala) and Glu could enhance the umami intensity of foods [34]. Umami constituted the predominant flavor profile of SEY; however, the proportion of sweet amino acids, namely serine (Ser), alanine (Ala), and glycine (Gly), was relatively minimal, accounting for merely 9.14% to 9.51% of the total amino acid composition. On this basis, the results of flavor amino acids and essential amino acids were followed by a similar trend of total amino acids. Interestingly, the changes in histidine (His) and cysteine (Cys-s) exhibited distinct patterns compared to other FAAs. Specifically, no significant variation was observed in the content of His, one of the bitter-tasting amino acids. This finding may elucidate that microwaving and baking were not conducive to the production of bitter amino acids. Meanwhile, microwaves appeared to facilitate the degradation of Cys-s. Above all, heating methods had hardly any effects on most of the FAAs. It was shown from a study demonstrated that cooking did not alter the ratio of essential amino acids to non-essential amino acids in eggs [3], which remained within a range of 76.99% to 79.11%, in agreement with the results concluded in the current work. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Fathy Acids** & **Steaming** & **Baking** & **Microwaving** \\ \hline C14:0 & 0.26 \(\pm\) 0.01 b & 0.30 \(\pm\) 0.01 a & 0.25 \(\pm\) 0.01 b \\ C16:0 & 25.45 \(\pm\) 0.08 ab & 26.11 \(\pm\) 0.71 a & 24.77 \(\pm\) 0.33 b \\ C16:1 & 3.90 \(\pm\) 0.49 & 4.34 \(\pm\) 0.75 & 3.37 \(\pm\) 0.30 \\ C17:0 & 0.17 \(\pm\) 0.02 a & 0.15 \(\pm\) 0.01 b & 0.19 \(\pm\) 0.00 a \\ C17:1 & 0.16 \(\pm\) 0.00 & 0.15 \(\pm\) 0.01 & 0.16 \(\pm\) 0.01 \\ C18:0 & 8.01 \(\pm\) 0.28 b & 7.92 \(\pm\) 0.11 b & 8.49 \(\pm\) 0.10 a \\ C18:1 & 42.66 \(\pm\) 1.19 & 42.94 \(\pm\) 2.35 & 42.73 \(\pm\) 0.27 \\ C18:2 & 14.76 \(\pm\) 0.95 ab & 13.71 \(\pm\) 0.66 b & 15.82 \(\pm\) 0.31 a \\ C18:3n6 & 0.11 \(\pm\) 0.01 & 0.09 \(\pm\) 0.00 & 0.09 \(\pm\) 0.01 \\ C18:3n3 & 0.34 \(\pm\) 0.06 & 0.36 \(\pm\) 0.04 & 0.36 \(\pm\) 0.01 \\ C20:1 & 0.20 \(\pm\) 0.01 & 0.22 \(\pm\) 0.02 & 0.21 \(\pm\) 0.01 \\ C20:2 & 0.17 \(\pm\) 0.01 & 0.18 \(\pm\) 0.03 & 0.17 \(\pm\) 0.00 \\ C20:3 & 2.57 \(\pm\) 0.12 & 2.39 \(\pm\) 0.18 & 2.38 \(\pm\) 0.01 \\ C22:6 & 1.00 \(\pm\) 0.18 & 0.94 \(\pm\) 0.04 & 0.79 \(\pm\) 0.02 \\ Others & 0.22 \(\pm\) 0.03 & 0.22 \(\pm\) 0.03 & 0.20 \(\pm\) 0.01 \\ \(\Sigma\) SFA 1 & 34.03 \(\pm\) 0.39 & 34.59 \(\pm\) 0.85 & 33.84 \(\pm\) 0.44 \\ \(\Sigma\) MUFA 2 & 46.99 \(\pm\) 1.70 & 47.73 \(\pm\) 3.13 & 46.53 \(\pm\) 0.59 \\ \(\Sigma\) PUFA 3 & 18.97 \(\pm\) 1.33 & 17.68 \(\pm\) 0.95 & 19.63 \(\pm\) 0.36 \\ \hline \hline \end{tabular} \({}^{\dagger}\)Saturated fatty acids. 2 Monunsaturated fatty acids. 3 Polyunsaturated fatty acids. Different letters in the same row indicated significant differences (\(p<0.05\)).  
\end{table} 
Table 1: Fatty acid profile (% total fatty acid) according to the different cooking methods of SEY.