Table 1.

Analysis of pH and ammonia content of in vitro fermentation samples.

Extraction method	pH value	Ammonia content (μmol/L)
Blank	6.89 ± 0.37a	1,849.94 ± 385.82a
HE	5.28 ± 0.57b	1,287.81 ± 290.25b
UE	4.83 ± 0.49cd	709.21 ± 149.43d
SE	4.87 ± 0.32c	764.72 ± 176.61c
ME	4.63 ± 0.33cd	679.73 ± 166.91e
INU	4.31 ± 0.45d	580.11 ± 128.50g

HWE, UE, SWE, and ME stand for dietary fiber extracted with hot water, ultrasonic assisted, subcritical water, and microwave assisted methods, respectively. INU stands for inulin. Different letters a, b and c indicate significant differences (p < 0.05), and the same letters indicate that the difference is not significant (p > 0.05).