Table 4. Reaction rate constant by quality index of R. verniciflua doenjang stew sauce

Quality index	Reaction order	Temp. (°C)	Regression equation	R2	Activation energy (Ea)
pH	Zero order	25	Y=−0.0013X+5.5705	0.8677	−17868.68
		35	Y=−0.0040X+5.5680	0.9441
		45	Y=−0.0089X+5.5967	0.9971
	First order	25	Y=−0.0002X+1.7175	0.8692	−18210.83
		35	Y=−0.0007X+1.7171	0.9461
		45	Y=−0.0017X+1.7228	0.9964
Titratable acidity (mL/g)	Zero order	25	Y=0.0014X+1.0868	0.8335	−19944.12
		35	Y=0.0057X+1.0838	0.9844
		45	Y=0.0118X+1.0528	0.9927
	First order	25	Y=0.0013X+0.0832	0.8229	−18030.91
		35	Y=0.0046X+0.0845	0.9754
		45	Y=0.0086X+0.0706	0.9902
Hunter color a*	Zero order	25	Y=−0.0067X+1.3445	0.9687	−17749.09
		35	Y=−0.0341X+1.2375	0.9491
		45	Y=−0.0434X+0.9662	0.9190
	First order	25	Y=−0.0021X+0.5418	0.9659	−23405.97
		35	Y=−0.0148X+0.5368	0.9750
		45	Y=−0.0251X+0.4926	0.9889
Hunter color b*	Zero order	25	Y=−0.0072X+4.0221	0.9889	−17213.14
		35	Y=−0.0177X+3.8704	0.9503
		45	Y=−0.0445X+3.7993	0.9795
	First order	25	Y=−0.0019X+1.3925	0.9897	−21258.48
		35	Y=−0.0052X+1.3575	0.9661
		45	Y=−0.0179X+1.3875	0.9938