Table 2.

Reduction of US and US-TEON treatment and the synergistic effect (log CFU/mL) against E. coli O157:H7 at different processing intensities and durations.

Treatments	64 W/cm2			191 W/cm2			382 W/cm2			573 W/cm2
	9 min	18 min	27 min	9 min	18 min	27 min	9 min	18 min	27 min	9 min	18 min	27 min
US	0.76 ± 0.09h	1.38 ± 0.06f	1.54 ± 0.11ef	0.82 ± 0.01h	1.59 ± 0.10e	1.66 ± 0.01e	0.81 ± 0.04h	1.96 ± 0.05d	3.13 ± 0.12b	1.15 ± 0.01g	2.50 ± 0.03c	3.52 ± 0.19a
US-TEON	2.16 ± 0.06i	2.87 ± 0.08h	4.46 ± 0.11d	2.93 ± 0.07h	3.71 ± 0.14e	4.97 ± 0.11c	3.37 ± 0.06f	4.48 ± 0.10d	6.49 ± 0.14b	3.63 ± 0.02e	5.02 ± 0.05c	7.10 ± 0.02a
Synergistic effect	0.19 ± 0.07f	0.28 ± 0.10f	1.71 ± 0.13c	0.90 ± 0.07e	0.91 ± 0.13e	2.10 ± 0.03b	1.29 ± 0.04d	1.30 ± 0.03d	2.15 ± 0.17b	1.27 ± 0.01d	1.31 ± 0.04d	2.37 ± 0.02a

Note:

The microbial reduction by TEON was 1.21 ± 0.03 log CFU/mL.

Synergistic effect (log CFU/mL) was estimated by applying the following equation: Synergistic effect = R_US-TEON - (R_US + R_TEON). Where, R_US-TEON represents the microbial reduction resulting from the application of US-TEON; R_US and R_TEON represents the microbial reduction resulting from the exclusive application of US or TEON, respectively.

The experiments were carried out three times. Error bars indicate the standard deviation of three technical replicates.

Values with different letters in the same row showed a significant difference at P < 0.05.