Predictive Growth Modeling of Listeria monocytogenes in Rice Balls and Its Risk Assessment

Table 1

Secondary models developed for the specific growth rate (SGR, log CFU/g/h) and lag time (LT, h) of L. monocytogenes in rice balls and statistical validation factors calculated for Baranyi models.

Code	Equation	R^2	Tmin (°C)	Storage temperature
				7°C	15°C	25°C
LTM^1)	SGR = −0.0109 + 0.0127 × T + 0.0001 × T^2	0.99	−9.43	0.08 ± 0.004	0.20 ± 0.003	0.36 ± 0.02
	LT = 540.2198–43.118 × T + 0.8826 × T^2	0.99		278.53 ± 15.34	93.62 ± 1.30	14.41 ± 0.59
LTS	SGR = –0.0155 + 0.0039 × T + 0.0001 × T^2	0.97	−3.02	0.02 ± 0.00	0.06 ± 0.01	0.15 ± 0.02
	LT = 87.2021–5.5066 × T + 0.0133 × T^2	0.99		52.07 ± 0.00	21.63 ± 3.56	−6.96 ± 0.75
LTG	SGR = 0.0889–0.0189 × T + 0.0012 × T^2	0.99	2.67	0.02 ± 0.002	0.08 ± 0.004	0.38 ± 0.01
	LT = 1.7491 + 6.3248 × T−0.24796 × T^2	0.98		30.75 ± 3.77	40.38 ± 1.98	4.91 ± 0.14
LHM	SGR = −0.0721 + 0.0217 × T−0.0004 × T^2	0.95	−15.40	0.06 ± 0.001	0.16 ± 0.008	0.21 ± 0.03
	LT = 530.4548–47.236 × T + 1.0475 × T^2	0.95		250.00 ± 5.35	58.05 ± 2.68	4.35 ± 0.48
LHS	SGR = 0.0325–0.0034 × T + 0.0004 × T^2	0.98	−3.34	0.03 ± 0.001	0.07 ± 0.003	0.19 ± 0.01
	LT = 287.397–30.0968 × T + 0.7449 × T^2	0.99		115.06 ± 5.14	3.71 ± 0.39	0.55 ± 0.04
LHG	SGR = 0.0418–0.0049 × T + 0.0004 × T^2	0.99	−2.73	0.03 ± 0.002	0.07 ± 0.006	0.20 ± 0.007
	LT = 87.4372–7.5618 × T + 0.1591 × T^2	0.99		42.55 ± 2.53	9.75 ± 0.87	−2.19 ± 0.07

1) LTM, LTS, and LTG are tuna rice balls mixed with mayonnaise, soy sauce, and gochujang contaminated by L. monocytogenes; LHM, LHS, and LHG are ham rice balls mixed with mayonnaise, soy sauce, and gochujang contaminated by L. monocytogenes.