where Xi is the fractional weight of a component i (e.g.
sucrose, glucose..); ai the index value assigned for that
particular component and Y is the overall index. The
index values were calculated so that when Y< 1 drying is
dicult, Y1 indicates a marginally successful drying,
and Y> 1 a successful drying. Powder recovery was
again used as the criterion for spray drying performance.
Eq. (7) was found to be useful in determining
optimum additive requirements for honey and pineapple
juice drying (Bhandari et al., 1997b).