## 3 Results and Discussion
### Contents of Amino Acids  
Free amino acids are of great importance in eating quality due to their specific tastes and important flavor and flavor precursor substance in chicken meat [40]. The amino acid profiles of breast meat from BJY, LH, and AA broilers are depicted in Table 3.  
It is clear that the predominant amino acids in the essential fraction were leucine and lysine in all chicken breeds. In the nonessential fraction, glutamic acid was the richest amino acid. Similar results were also reported in previous studies. [PERSON] et al. [5] found that glutamic acid in the nonessential fraction and lysine and leucine in the essential fraction were also major amino acids in 817 crossed chickens (a commercial Chinese crossed chicken), AA broilers, and Hyline Brown (commercial spent hens). The same results were also found in some other meat such as e  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Nucleotides** & **BJY** & **AA** & **LH** \\ \hline GMP & 5.87 \(\pm\) 0.501 1  & 4.19 \(\pm\) 0.01 2  & 6.15 \(\pm\) 0.37 3  \\ IMP & 459.77 \(\pm\) 24.98  & 247.25 \(\pm\) 20.22  \\ Hx & 8.63 \(\pm\) 0.35 4  & 63.46 \(\pm\) 4.47 5  & 13.81 \(\pm\) 0.50 5  \\ HxR & 62.27 \(\pm\) 3.15  & 147.26 \(\pm\) 9.74  & 60.73 \(\pm\) 4.04  \\ \hline \hline \end{tabular}
\end{table}
Table 2: Nucleotide contents of different types of chicken breast (mg/100 g).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Amino Acid (mg/100 g)** & **BJY** & **LH** & **AA** \\ \hline Asp (Aspartic acid) & 7.04 \(\pm\) 0.28 2  & 1.13 \(\pm\) 0.09 3  \\ Thr (Threonine) & 7.71 \(\pm\) 0.22 4  & 6.45 \(\pm\) 0.18  & 10.34 \(\pm\) 0.26 5  \\ Ser (Serine) & 4.56 \(\pm\) 0.04 6  & 6.16 \(\pm\) 0.17 7  & 7.84 \(\pm\) 0.40 6  \\ Glu ( Glutamic acid) & 82.02 \(\pm\) 4.31  & 64.66 \(\pm\) 0.37 7  & 57.95 \(\pm\) 0.57 8  \\ Gly (Glycine) & 10.97 \(\pm\) 0.49 1  & 8.93 \(\pm\) 0.00 1  & 11.38 \(\pm\) 0.21 1  \\ Ala (Alanine) & 15.82 \(\pm\) 0.71 1  & 14.56 \(\pm\) 0.47 1  & 21.95 \(\pm\) 0.50 1  \\ Cys (Cystine) & 0.76 \(\pm\) 0.04 1  & 0.92 \(\pm\) 0.06 2  & 0.71 \(\pm\) 0.06 1  \\ Val (Valine) & 19.12 \(\pm\) 0.81 1  & 18.98 \(\pm\) 0.95 1  & 14.98 \(\pm\) 0.93 2  \\ Met (Methionine) & 9.05 \(\pm\) 0.37 2  & 6.14 \(\pm\) 0.26 1 [FOOTNOTE:2]Footnote 2: \(\mathrm{a}\).b.c Means within a row with different superscripts differ significantly (\In this study, different chickens were significantly different (\(p<0.05\)) in their amino acid contents, with the exception of glutamic acid, glycine, alanine, valine, leucine, arginine, and proline in the breast. Regarding total essential amino acids, significant differences were found among all three groups. AA broilers contained relatively higher total essential amino acids (315.20 mg/100 g), followed by BJY and LH (296.02 mg/100 g and 263.33 mg/100 g, respectively). However, the essential amino acid contents of BJY chicken showed significantly higher values than LH and AA broilers in breast meat. Glutamic acid is an important flavor compounds of meat, which is an important contributor to the fresh taste of meat [43]. BJY chicken had the highest content of glutamic acid (82.02 mg/100 g) among these three chicken breeds. The content of glutamic acid in LH chicken was slightly higher than that in AA broilers, but there was no significant difference. [PERSON] et al. [44] also confirmed that the breast meat of Thai native chickens had higher glutamic acid compared with broiler chickens. Therefore, the results indicate that the chicken breed considerably affects the amino acid composition considerably. The high content of essential amino acids in the breast muscles of BJY chicken might suggest that the BJY chicken has more nutritional value to humans than LH and AA chicken.