Table 2: ANOVA for surface response quadratic polynomial model for citric acid production.

Factor Sum of squares (SS) Degree of Freedom Mean square F-value P-value Interpretation
A 5.50 1 5.50 5.68 0.0545 Significant
A2 4.02 1 4.02 4.15 0.0877 Marginally significant
B 11.13 1 11.14 11.49 0.0147 Significant
B2 1.14 1 1.17 1.18 0.3196
C 6.47 1 6.47 6.68 0.0414 Significant
C2 2.26 1 2.26 2.33 0.1772
D 8.27 1 8.27 8.53 0.0266 Significant
D2 0.39 1 0.39 0.40 0.5488
E 0.07 1 0.07 0.07 0.8013
E2 4.17 1 4.17 4.30 0.0833 Marginally significant
AB 0.49 1 0.49 0.51 0.5031
AC 4.36 1 4.37 4.51 0.0779 Marginally significant
AD 0.39 1 0.39 0.41 0.5444
AE 2.13 1 2.14 2.21 0.1878
BC 2.03 1 2.03 2.09 0.1974
BD 3.69 1 3.69 3.82 0.0986 Marginally significant
BE 2.08 1 2.08 2.15 0.1929
CD 0.65 1 0.65 0.68 0.4410
CE 0.59 1 0.59 0.61 0.4629
DE 0.17 1 0.17 0.17 0.6864
Error 5.8139 6 0.9690
Total SS 53.0265 26