From Table 2 and Fig. 3, it is observed that the addition of
sucrose behenate resulted in some changes to the characteristics
of the microstructure of each fat. The incorporation of sucrose
behenate in the interesterified fat and palm mid fraction resulted
in a larger crystal diameter (6.0 lm). One explanation for this
effect would be the instantaneous nucleation shown by these samples,
i.e., the faster formation of crystalline nuclei, while to palm oil
the addition of sucrose behenate resulted in the reduction of the
crystal diameter (from 10 lm to 6.0 lm). Puppo, Martini,
Hartel, and Herrera (2002) observed that the addition of sucrose
esters to milk fat caused a decrease in the size of the crystals and
this resulted in a lower hardness in the samples. The relationship
between hardness and microstructure could be deduced through
the crystal network organization. Samples with distribution and
size of the crystals more homogeneous will provide greater
resistance than heterogeneous samples. In this case the mechanical
strength is more related to interaction strength between
microstructural components of fat (Campos, Narine, &
Marangoni, 2002). The effect of sucrose behenate on the size of
the crystals formed in the different fats indicates that the emulsifier
co-crystallized with the fat, interfering with its crystallization
properties. Martini et al. (2002) presented results on the effect of
the addition of P-170 and S-170 on the crystallization of milk fat
mixed with sunflower oil. Although the addition of these sucrose
esters reduced the size of the crystals, it also delayed nucleation.
No study to date has used sucrose behenate as a modifier for fat
crystallization.
Fig. 3 shows the images of the microstructure of the fats at 20
and 25 C. At 20 C, greater crystal uniformity and size were
observed in palm oil after the addition of sucrose behenate.
However, for the interesterified fat, some crystalline nuclei of
greater diameter, spread out in a thin network of small crystals,
were observed. The greatest change in the organization of the crystalline
network was observed in the palm mid fraction containing
sucrose behenate, where the presence of the liquid phase was well
distributed over the entire network.
Thus, the addition of sucrose behenate altered the spatial distribution
of the crystals in the crystalline network of the fats, and
suggested that the crystallization mechanisms previously mentioned
are in agreement with the microstructures of the fats and
their blends with sucrose behenate.
From Table 2 and Fig. 3, it is observed that the addition ofsucrose behenate resulted in some changes to the characteristicsof the microstructure of each fat. The incorporation of sucrosebehenate in the interesterified fat and palm mid fraction resultedin a larger crystal diameter (6.0 lm). One explanation for thiseffect would be the instantaneous nucleation shown by these samples,i.e., the faster formation of crystalline nuclei, while to palm oilthe addition of sucrose behenate resulted in the reduction of thecrystal diameter (from 10 lm to 6.0 lm). Puppo, Martini,Hartel, and Herrera (2002) observed that the addition of sucroseesters to milk fat caused a decrease in the size of the crystals andthis resulted in a lower hardness in the samples. The relationshipbetween hardness and microstructure could be deduced throughthe crystal network organization. Samples with distribution andsize of the crystals more homogeneous will provide greaterresistance than heterogeneous samples. In this case the mechanicalstrength is more related to interaction strength betweenmicrostructural components of fat (Campos, Narine, &Marangoni, 2002). The effect of sucrose behenate on the size ofthe crystals formed in the different fats indicates that the emulsifierco-crystallized with the fat, interfering with its crystallizationproperties. Martini et al. (2002) presented results on the effect ofthe addition of P-170 and S-170 on the crystallization of milk fatmixed with sunflower oil. Although the addition of these sucroseesters reduced the size of the crystals, it also delayed nucleation.No study to date has used sucrose behenate as a modifier for fatcrystallization.Fig. 3 shows the images of the microstructure of the fats at 20and 25 C. At 20 C, greater crystal uniformity and size wereobserved in palm oil after the addition of sucrose behenate.However, for the interesterified fat, some crystalline nuclei ofgreater diameter, spread out in a thin network of small crystals,were observed. The greatest change in the organization of the crystallinenetwork was observed in the palm mid fraction containingsucrose behenate, where the presence of the liquid phase was welldistributed over the entire network.Thus, the addition of sucrose behenate altered the spatial distributionof the crystals in the crystalline network of the fats, andsuggested that the crystallization mechanisms previously mentionedare in agreement with the microstructures of the fats andtheir blends with sucrose behenate.
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