Yield, recovery and α-amino group content of hydrolyzed collagen (HC) from defatted Asian sea bass skin prepared using different hydrolysis processes^a.

Samples	Yield (%)	Recovery (%)	α-Amino group content (mmol GE/g sample)
A0.2	12.19 ± 0.94D	16.16 ± 0.44E	0.12 ± 0.00CD
A0.3	15.87 ± 0.08B	17.90 ± 0.95D	0.13 ± 0.00C
P0.3	14.42 ± 0.52C	19.54 ± 0.17C	0.11 ± 0.00D
P0.3 + A0.2	16.91 ± 0.02B	21.55 ± 0.22B	0.21 ± 0.00B
P0.3 + A0.3	20.00 ± 0.37A	25.99 ± 0.28A	0.22 ± 0.00A

^aValues are mean ± SD (n = 3). Different superscripts in the same column indicate significant difference (p < 0.05). A0.2 or A0.3: HC prepared from defatted skin using Alcalase at 0.2 or 0.3 units per g dry matter at 50 °C for 90 min; P0.3: HC prepared from defatted skin using papain at 0.3 unit per g dry matter at 40 °C for 90 min; P0.3 + A0.2 or P0.3 + A0.3: HC prepared from defatted skin using papain at 0.3 unit per g dry matter, followed by hydrolysis using Alcalase at 0.2 or 0.3 unit per g dry matter, respectively.