Volume expansion (cm3) Moisture loss (%) Loaf height (cm) Hardness (N/g)
Sequential sum of squares Qua ** ** **  
  2FI       **
Lack of fitb Qua ns ns ns  
  2FI       *
R2 Qua ** ** **  
  2FI       **
  Qua 0.9614 0.9893 0.8527  
  2FI       0.8827
Selected model   Qua Qua Qua 2FI
t-testsc          
A   ** ** ** *
B   ** ** ** ns
C   ** ** ** ns
D   ** ** ** *
AB   ** ** ** *
AC   ** ** ** ns
AD   ** ** ** *
BC   ** ** ** *
BD   ** ** ** *
CD   ** ** ** ns
A2   ** ** ** -
B2   ** ** ** -
C2   ** ** ** -
D2   ** ** ** -
Remarks   - - - Slight lack of fit
a *, P < 0.01; **, P < 0.001; ns, not significant; 2FI, two factor interaction;
Qua, quadratic.
F-test for significance of adding the quadratic terms to the 2FI model.
bComparison of residual error to pure error from the replicated center points.
c t-tests, whether the respective coefficient is different from 0 (H0: coefficient = 0 vs. HA: coefficient ≠ 0).
A=egg albumin, B=milk powder, C=temperature, D=time
Table 6: Models for selected response (fit summaries and F-tests for model coefficients)a.