151
viscosity which however increased the fluidity and consistency for the solutions.
Marquis et al. (2015) reports that this technique can provide for the formulation of
monodisperse spherical and non spherical polymeric microparticles apart from providing the versatile geometry. In brief, microparticles of pectin hydrogels which
vary in shape, (oblate ellipsoid, torus or mushroom type) and morphology can be
generated using the technique of microfluidization.
Modification of Pectin with Enzymatic Treatment
A number of enzymes are utilized for modifying the pectin in a more precise way.
These are commercially obtained and purified from sources like Aspergillus niger
and include the enzymes like galactanase, arabinase, pectin methyl esterase (PME)
and pectin acetyl esterase (PAE). The enzymes can produce highly modified pectins which has tremendous commercial applications. For instance pectins having
high DM are frequently modified using PMEs (Owen et al. 2017). It is important to
mention that the variation in PME can affect the final properties of pectin and further the degree As in case of processive PMEs, blockier distributions are possible
because the enzyme is capable of moving along the chain and hydrolysing the
consecutive methyl esters. This results in the presence of consecutive unmethylesterfied residues even at high DM. In case of non-processive PME, the enzyme after
binding to HG chain removes only one methyl ester and later dissociates again
which results in formation of residues that are randomly unmetylesterfied. The
resulting pectins have different patterns of DM with peculiar calcium sensitivities,
different degrees of network formation and polyelectrolytic effects. Another
enzyme, i.e. PAE also functions in modifying the pectin by deacetyation of pectin.
In a study carried out by Oosterveld et al. (2000) sugar beet pectin was incubated
with the combination of PAE and pectin esterase in presence of Ca2þ ions releasing
13.8% of the acetyl groups 27.2% of methyl ester groups. One of the disadvantages
of this treatment in such case the modified pectin obtained is resistant to the attack
of pectin esterase due to the presence of acetyl groups which results in its non
homgenity. The rheological and conformational properties of the pectin are dependent upon the degree of methoxylation. As a result, pectins having higher degree of
methylesterification and galacturonic acid content can provide a good source of
substrate for modification. There are few enzymes which allow for the modification
of pectin and also helps in assessing the effects of various constituents in RG-I side
chains on the gelling capabilities of pectin. These include endo-a-1,5-arabinanase
and endo-b-1,4- galactanase. Their enzymatic treatment has various implications on
the gelling temperature and gel strength of the debranched pectin. Following the
reduction in neutral sugar concentration, it reduces the gelling temperature and gel
strength in debranched pectin. The enzymatically extracted pectin possesses a
higher degree of esterification and finds a great commercial application as so-called
Ultra-Rapid-Set pectin. The unique property of this gel is that it gels rapidly at
higher temperature.
Pectin
viscosity which however increased the fluidity and consistency for the solutions.
Marquis et al. (2015) reports that this technique can provide for the formulation of
monodisperse spherical and non spherical polymeric microparticles apart from providing the versatile geometry. In brief, microparticles of pectin hydrogels which
vary in shape, (oblate ellipsoid, torus or mushroom type) and morphology can be
generated using the technique of microfluidization.
Modification of Pectin with Enzymatic Treatment
A number of enzymes are utilized for modifying the pectin in a more precise way.
These are commercially obtained and purified from sources like Aspergillus niger
and include the enzymes like galactanase, arabinase, pectin methyl esterase (PME)
and pectin acetyl esterase (PAE). The enzymes can produce highly modified pectins which has tremendous commercial applications. For instance pectins having
high DM are frequently modified using PMEs (Owen et al. 2017). It is important to
mention that the variation in PME can affect the final properties of pectin and further the degree As in case of processive PMEs, blockier distributions are possible
because the enzyme is capable of moving along the chain and hydrolysing the
consecutive methyl esters. This results in the presence of consecutive unmethylesterfied residues even at high DM. In case of non-processive PME, the enzyme after
binding to HG chain removes only one methyl ester and later dissociates again
which results in formation of residues that are randomly unmetylesterfied. The
resulting pectins have different patterns of DM with peculiar calcium sensitivities,
different degrees of network formation and polyelectrolytic effects. Another
enzyme, i.e. PAE also functions in modifying the pectin by deacetyation of pectin.
In a study carried out by Oosterveld et al. (2000) sugar beet pectin was incubated
with the combination of PAE and pectin esterase in presence of Ca2þ ions releasing
13.8% of the acetyl groups 27.2% of methyl ester groups. One of the disadvantages
of this treatment in such case the modified pectin obtained is resistant to the attack
of pectin esterase due to the presence of acetyl groups which results in its non
homgenity. The rheological and conformational properties of the pectin are dependent upon the degree of methoxylation. As a result, pectins having higher degree of
methylesterification and galacturonic acid content can provide a good source of
substrate for modification. There are few enzymes which allow for the modification
of pectin and also helps in assessing the effects of various constituents in RG-I side
chains on the gelling capabilities of pectin. These include endo-a-1,5-arabinanase
and endo-b-1,4- galactanase. Their enzymatic treatment has various implications on
the gelling temperature and gel strength of the debranched pectin. Following the
reduction in neutral sugar concentration, it reduces the gelling temperature and gel
strength in debranched pectin. The enzymatically extracted pectin possesses a
higher degree of esterification and finds a great commercial application as so-called
Ultra-Rapid-Set pectin. The unique property of this gel is that it gels rapidly at
higher temperature.
Pectin