Pectin has previously been used as a carrier to target
drugs to the colon in many studies (Elyagoby et al.,
2013; Jung et al., 2013). In this study, the HMP is
used as it has different gelling mechanism from that of
the low methoxyl pectin (LMP). The LMP forms gel
usually by ionotropic gelation with bivalent or polyvalent
metal ion (usually Ca2+). However, the HMP
forms gel beads when pH is between 2.5 and 3.5 under
suitable conditions corresponding to that of the gastric
fluid. Therefore, complexes of SPI–HMP were
designed in the current study to encapsulate L. delbrueckii.
A viable counting method was used to evaluate
the release rate and detect whether the complexes
had a protective effect. Specifically, signal-factor experiments
were performed to optimise the preparation
profiles.