4. Discussion
The firmness of the yoghurt gel-network could be basically
positively or negatively influenced by the addition of products such
as Actilight or isomaltulose. This study was performed to find out
how Actilight in combination with Stevia or with isomaltulose
influences the physical and sensory properties of set yoghurt when
compared with sucrose at two different fat levels. It was assumed
that Stevia concentrations were too low to influence the consistency
properties. The analysed protein contents of the experimental
yoghurts were almost identical at each fat level, while the
total solids content differed. The chemical composition, including
three aroma compounds, organic acids and pH values, proved
that the standard technological yoghurt-making process or the
pH development were not negatively affected by the addition of
either Actilight (0e6%) together with Stevia or isomaltulose (8%)
compared with the sucrose (8%). The pH of plain set yoghurt was
not influenced by the incorporation of 6 different fibres as reported
by Aryana (2006).