These differences may be the result of the direct substitution of fat for
inulin, as carried out in this study, compared to sausages formulated
with inulin (no direct fat substitution) in the aforementioned study.
However, the retention of fluids as seen in the present study could be
attributed to inulin's capacity to form networks of interacting microcrystals
that aggregate to occlude substantial amounts of water (Bot,
Erle, Vreeker, & Agterof, 2004).
3.3. Instrumental texture
Inulin addition significantly affected the sausage texture (Table 5).
Four of the five texture parameters were found to differ significantly,
with the exception of cohesive force. Sausage hardness ranged from
39.8 N (full fat controls) to 126.1 N [full inulin (GR) substitution]
sausages containing more inulin than sausages formulated with
fat (Fig. 3a). The predicted linear model for hardness which was
transformed using an inverse square root was found to be significant
(p b 0.0001) and showed a good fit with the experimental data
(R2 = 0.75) (Table 3). In excess of a three-fold increase in hardness resulted
fromthe full substitution of fatwith inulin,with the effects slightly
more pronounced for sausages formulatedwith Orafti GR.While both
inulin products had the same overall trend (increasing hardness), one
might expect products containing Orafti HP to result in harder products
as usually a higher DP is characteristic of higher mechanical strength.
Similar trends were observed for gumminess and chewiness (transformed
inverse square root) (Fig. 3b–c) in inulin enriched sausages,
although, the increases (p b 0.0498 and 0.0087) and linear model fits
(R2 = 0.35 and 0.45 respectively) to experimental data were less pronounced.
Gumminess and chewiness are secondary parameters that
rely on hardness and often behave similarly (Selgas et al., 2005). This
is highlighted experimentally by their high Pearson coefficient
(Table 4). Sausages containing a higher proportion of fat were more
Fig. 3.