Table 4. Changes in the free amino acid composition of loin and ham peptide extracts from JBP and LYD after In vitro digestion

Amino acid	Free amino acid content (mg/g dw)
	Loin				Ham
	JBP		LYD		JBP		LYD
	Before digestion	After digestion	Before digestion	After digestion	Before digestion	After digestion	Before digestion	After digestion
Aspartic acid	0.20	0.13	0.39	0.28	0.15	0.08	0.34	0.26
Threonine	0.46	2.62	0.55	2.50	0.53	2.74	0.47	2.70
Serine	0.53	1.70	0.62	1.65	0.55	1.79	0.53	1.78
Asparagine	0.77	1.93	0.97	2.03	0.79	2.09	0.92	2.32
Glutamic acid	2.61	3.00	4.64	4.64	3.07	3.50	4.31	5.19
Glutamine	0.27	4.26	0.33	3.55	0.41	4.60	0.53	4.52
Glycine	0.26	0.31	0.29	0.32	0.28	0.36	0.24	0.38
Alanine	1.21	3.68	1.47	3.63	1.38	3.78	1.46	3.70
Valine	0.59	2.91	0.88	2.95	0.67	3.05	0.74	3.10
Methionine	0.84	6.26	1.25	5.90	1.07	6.29	1.30	6.66
Isoleucine	1.72	5.33	2.18	5.15	1.77	5.66	2.03	5.85
Leucine	3.72	24.83	5.47	23.93	4.66	26.19	5.44	26.68
Tyrosine	1.56	16.70	1.77	15.31	1.58	17.47	1.88	17.38
Phenylalanine	0.95	16.11	1.10	15.03	0.99	16.54	1.12	16.82
Tryptophan	ND	2.71	ND	2.50	ND	2.90	ND	2.72
Ornithine	0.32	0.51	0.59	0.55	0.31	0.51	0.50	0.67
Lysine	1.16	22.17	1.83	20.99	1.31	23.67	1.40	24.84
Histidine	0.11	2.41	0.16	2.19	0.12	2.50	0.12	2.52
Arginine	1.20	27.85	1.89	28.60	1.43	30.09	1.80	30.78
Proline	0.34	1.14	0.32	0.96	0.43	1.10	0.35	1.14
Carnosine	ND	ND	ND	ND	ND	ND	ND	ND
Total	18.82	146.56	26.70	142.66	21.50	154.91	25.48	160.01

dw, dry weight; JBP, Jeju black pigs; LYD, three-way crossbred pigs (Landrace × Yorkshire × Duroc); ND, not detected.