Table 1: Gompertz parameters regarding the production of CO2 by coliforms of mozzarella cheese in the head space of sealed vials, incubated at 37 ℃. For each parameter the letters indicate significant differences (one-way ANOVA, P < 0.05).

(CO2)max* μmax λ MDT R2 Cell loadc
Control
0b 20.41 ± 0.69 F 1.21 ± 0.15 D,E,F,G 9.22 ± 1.98 A,B 10.63 ± 1.57 A,B 0.998 3.46 ± 0.24 C
1 20.29 ± 0.83 F 1.27 ± 0.14 E,F,G,H 9.44 ± 1.54 A,B 10.75 ± 1.21 A,B 0.998 3.43 ± 0.19 C
3 19.37 ± 0.18 F 1.66 ± 0.07 H,I 9.96 ± 0.51 A,B 10.98 ± 0.44 A,B 0.998 4.07 ± 0.05 D
6 20.06 ± 0.53 F 1.32 ± 0.10 F,G,H 9.04 ± 1.00 A,B 10.34 ± 0.78 A,B 0.998 5.53 ± 0.19 E
8 20.43 ± 0.57 F 1.19 ± 0.07 D,E,F,G 7.29 ± 0.81 A 8.86 ± 0.55 B 0.998 5.87 ± 0.08 E
Na2-EDTA 50 mM
0 19.84 ± 0.93 F 1.55 ± 0.23 G,H,I 11.56 ± 1.54 B 12.95 ± 1.18 B,C 0.988 3.46 ± 0.24 C
1 20.56 ± 0.99 F 0.60 ± 0.07 B,C 11.92 ± 2.27 B 14.81 ± 1.52 C 0.994 3.19 ± 0.21 C
3 15.52 ± 0.20 E 0.83 ± 0.16 B,C,D 20.41 ± 0.67 C,D 22.83 ± 0.28 E 0.998 1.22 ± 0.11 A
6 6.37 ± 0.06 B 0.51 ± 0.03 A,B 19.96 ± 0.32 C,D 24.37 ± 0.11 E 0.998 1.16 ± 0.09 A
8 3.40 ± 0.12 A 0.12 ± 0.01 A 25.20 ± 1.13 E 45.87 ± 1.13 G 0.996 -e
Na2-EDTA 20 mM
0 19.47 ± 0.78 F 1.85 ± 0.29 I 11.98 ± 1.38 B 13.04 ± 1.09 B,C 0.992 3.46 ± 0.24 C
1 19.19 ± 1.60 F 0.95 ± 0.20 C,D,E,F 17.41 ± 2.24 C 19.03 ± 1.89 D 0.986 3.18 ± 0.25 C
3 14.64 ± 0.20 D,E 0.91 ± 0.04 B,C,D,E 19.37 ± 0.32 C,D 21.68 ± 0.22 D,E 0.998 1.93 ± 0.05 B
6 12.64 ± 0.06 C,D 1.47 ± 0.02 G,H,I 22.84 ± 0.05 D,E 24.25 ± 0.04 E 0.998 1.47 ± 0.18 A,B
8 10.97 ± 0.05 C 1.19 ± 0.02 D,E,F,G 26.32 ± 0.09 E 28.19 ± 0.05 F 0.998 -

*(CO2)max: Maximum increase of the amount of CO2 attained in the headspace (%, v/v); μmax: Maximal rate of CO2 production (CO2/h); λ: Time (h) before the beginning of the production of CO2; MDT: Minimum detection time (h); R2: Determination coefficient. The parameters are accompanied by the standard error; bDays of storage at 4 ℃ of mozzarella cheese; clog CFU/g (mean values ± standard deviation); eBelow the detection limit.