temperatures. Total enthalpies of t

temperatures. Total enthalpies of these blends were also increased
with PS, and they ranged from 57.8 to 61.4 J/g (Table 2). This finding was consistent with those reported by Jeyarani and Reddy
(1999), who produced heat-resistant CB extenders by blending mahua and kokum fats. Moreover, these results are similar with those
of other studies for commercial CB (Solis-Fuentes & Duran-de-Bazua,
2004), in which the crystallization onset, offset and enthalpies were
found to be at 12.7C,26.2C, and 57.0 J/g, respectively.
Blends No. 5–10, on the other hand, showed two distinct crystallization peaks where a broad peak in the lower temperature region with an exothermic onset, which ranged from 18.9 to 23.0C,
and a sharp peak in the higher temperature region with an exothermic onset of 13.2–17.0C(Fig. 2b). This indicated that higher
melting triglycerides (mainly are constituted of saturated fatty
acids) were present in those blends. There was a gradual increase
in the crystallization onset in the high temperature region with
the addition of PS. The opposite trends were observed for the crystallization onset temperature, where these temperatures gradually
decreased in low temperature region. Similar results were reported
for palm stearin/palm kernel olein blend by Chu et al. (2001)and
for mahua oil/kokum fat blend byJeyarani and Reddy (2010). The
maximum peak heights of the blends ranged from 12.2 to 21.5C
(Table 2). Significant changes in temperatures were observed
amongst the blends, which could be due to the blending ratios of
MSF and PS. The blends containing 80–95% MSF showed a maxima
at 12.2–12.7C. These findings were in good agreement with those
reported byJeyarani and Reddy (1999), where the crystallization
peak height for commercial CB was at 14.0C.
3.4. Solid fat content
The relationships between SFC and the temperatures of all
blends of MSF and PS are shown inFig. 3. Generally, the percentage
of SFC is related to temperature and it indicates both the hardness,
softness and the melting behaviour of fats and oils. The SFC should
be 0% at body temperature for good quality CBRs. In the present
study, all the blends had high solids at 10–25C and no solids at
37.5C, except for Blends No. 6–10. It can be seen fromFig. 3that
the SFC decreased as the temperature increased. For instance,
Blend 1, having 5% of PS, its SFC at 10C was 49%, which reduced
to 28.9% at 25C and no solids were present at 37.5C. The Blends
2–3, having 10–15% of PS, respectively, were also completely
melted at 37.5C, but they had a higher SFC at 25C. From 20 to
25C, the largest decrease in SFC was observed. This could be
due to large amounts of TGs which solubilise in this temperature
range. For all blends, the melting rate was higher at 20–25C than
between 15 and 20C. The SFC for Blends No. 1–4 was found to be
different from those of SFC of Blends No. 5–10 (Fig. 3). In Blends
No. 5–10, the SFC did not drop to 0% at 37.5C, and shifted to 0%
at and above 40C. These blends contain higher levels of SOS that
give higher melting temperatures similar to that reported for the
kokum fat and CB blend (Maheshwari & Reddy, 2005), and the mahua and kokum fat blend (Jeyarani & Reddy, 1999).
The SFC that still remained in the formulated blends at higher
temperature was due to the greater variation of TGs that resulted
from the addition of PS. Therefore, the results revealed that the
blending ratios of MSF and PS, together with the temperatures
used had a significant effect on the SFC. No significant changes in
the SFC were observed at higher temperatures. The SFC decreased
upon blending, which was due to the solubilisation and the
replacement of saturated fatty acids with unsaturated fatty acids
in the blended TGs. It has been well acknowledged that unsaturated fatty acids have lower melting points due to the presence
of double bonds (Rousseau, Forestiere, Hill, & Marangoni, 1996).
Therefore, when PS was used in place of the palm oil mid-fraction,
there was improvement in the SFC observed in certain blends. This
was due to the presence of high melting fractions of PS. To decrease
the melting range to that of commercial CB, MSF was incorporated
into the PS. The blends containing 5–20% of PS (Blends 1–4)
showed melting peaks similar to that of commercial CB. Moreover,
owing to the higher SFC and SOS than CB, certain blends could be
used to increase the hardness of CB. These blends of MSF and PS
may be advantageous for use in warm climates.
3.5. Morphological study
Fig. 4shows the polarised light microphotographs obtained at
the end of the crystallization process for blends of MSF and PS.
The fat crystal network microstructures of the blends were found
to be a mixture of various crystal morphologies. The crystals with
quite different morphology were observed amongst the studied
blends. The granular structures of the crystal, similar to that of
commercial CB were observed in Blends 1–4, having 80–95% of
MSF. The changes in the microstructures were more prominent
with the addition of PS. The large spherulitic microstructures
showed and consisted of a needle-like periphery and a granular
centre with the addition of PS (Fig. 4a–d). Similar results for
commercial CB were reported byBrunello, McGauley, and Marangoni (2003). In another study, Toro-Vazquez, Pérez-Martínez,
Dibildox-Alvarado, Charó-Alonso, and Reyes- Hernández (2004)
reported that for CB crystallised at 22C, the microstructure of
the crystals was spherulites formed by needle-like structures.
4. Conclusions
In this work, a series of blends (1–10) of MSF and PS for formulating CBRs have been prepared and examined in terms of TG
compositions, melting and crystallization profiles, SFC and morphology. The results of this study suggested that certain blends
of MSF and PS could be used to prepare CBRs without significantly
altering the physical and chemical properties of the product. These
blends mainly consisted of three TGs (POP, POS and SOS), from the
main TG components of commercial CB. The formulations had
melting and crystallization properties, in particular the onset, offset and enthalpies similar to that of commercial CB, although they
showed delayed crystallization to the stable form. Polarised light
microscope (PLM) images showed significant changes in the crystal
morphology within the blends. The formulations showed a higher
SFC at 20–25C and did not decrease to 0% at 37.5C and shifted to
0% at and above 40C. These blends could be used for the production of high temperatures resistant hard butter for countries with a
hot climate. Moreover, blends of MSF and PS could solve the
tempering difficulties for chocolate manufacturers in tropical

Hasil (Bahasa Indonesia) 1:

temperatures. Total enthalpies of these blends were also increasedwith PS, and they ranged from 57.8 to 61.4 J/g (Table 2). This finding was consistent with those reported by Jeyarani and Reddy(1999), who produced heat-resistant CB extenders by blending mahua and kokum fats. Moreover, these results are similar with thoseof other studies for commercial CB (Solis-Fuentes & Duran-de-Bazua,2004), in which the crystallization onset, offset and enthalpies werefound to be at 12.7C,26.2C, and 57.0 J/g, respectively.Blends No. 5–10, on the other hand, showed two distinct crystallization peaks where a broad peak in the lower temperature region with an exothermic onset, which ranged from 18.9 to 23.0C,and a sharp peak in the higher temperature region with an exothermic onset of 13.2–17.0C(Fig. 2b). This indicated that highermelting triglycerides (mainly are constituted of saturated fattyacids) were present in those blends. There was a gradual increasein the crystallization onset in the high temperature region withthe addition of PS. The opposite trends were observed for the crystallization onset temperature, where these temperatures graduallydecreased in low temperature region. Similar results were reportedfor palm stearin/palm kernel olein blend by Chu et al. (2001)andfor mahua oil/kokum fat blend byJeyarani and Reddy (2010). Themaximum peak heights of the blends ranged from 12.2 to 21.5C(Table 2). Significant changes in temperatures were observedamongst the blends, which could be due to the blending ratios ofMSF and PS. The blends containing 80–95% MSF showed a maximaat 12.2–12.7C. These findings were in good agreement with thosereported byJeyarani and Reddy (1999), where the crystallizationpeak height for commercial CB was at 14.0C.3.4. Solid fat contentThe relationships between SFC and the temperatures of allblends of MSF and PS are shown inFig. 3. Generally, the percentageof SFC is related to temperature and it indicates both the hardness,softness and the melting behaviour of fats and oils. The SFC shouldbe 0% at body temperature for good quality CBRs. In the presentstudy, all the blends had high solids at 10–25C and no solids at37.5C, except for Blends No. 6–10. It can be seen fromFig. 3thatthe SFC decreased as the temperature increased. For instance,Blend 1, having 5% of PS, its SFC at 10C was 49%, which reducedto 28.9% at 25C and no solids were present at 37.5C. The Blends2–3, having 10–15% of PS, respectively, were also completelymelted at 37.5C, but they had a higher SFC at 25C. From 20 to25C, the largest decrease in SFC was observed. This could bedue to large amounts of TGs which solubilise in this temperaturerange. For all blends, the melting rate was higher at 20–25C thanbetween 15 and 20C. The SFC for Blends No. 1–4 was found to bedifferent from those of SFC of Blends No. 5–10 (Fig. 3). In BlendsNo. 5–10, the SFC did not drop to 0% at 37.5C, and shifted to 0%at and above 40C. These blends contain higher levels of SOS thatgive higher melting temperatures similar to that reported for thekokum fat and CB blend (Maheshwari & Reddy, 2005), and the mahua and kokum fat blend (Jeyarani & Reddy, 1999).The SFC that still remained in the formulated blends at highertemperature was due to the greater variation of TGs that resultedfrom the addition of PS. Therefore, the results revealed that theblending ratios of MSF and PS, together with the temperaturesused had a significant effect on the SFC. No significant changes inthe SFC were observed at higher temperatures. The SFC decreasedupon blending, which was due to the solubilisation and thereplacement of saturated fatty acids with unsaturated fatty acidsin the blended TGs. It has been well acknowledged that unsaturated fatty acids have lower melting points due to the presenceof double bonds (Rousseau, Forestiere, Hill, & Marangoni, 1996).Therefore, when PS was used in place of the palm oil mid-fraction,there was improvement in the SFC observed in certain blends. Thiswas due to the presence of high melting fractions of PS. To decreasethe melting range to that of commercial CB, MSF was incorporatedinto the PS. The blends containing 5–20% of PS (Blends 1–4)showed melting peaks similar to that of commercial CB. Moreover,owing to the higher SFC and SOS than CB, certain blends could beused to increase the hardness of CB. These blends of MSF and PSmay be advantageous for use in warm climates.3.5. Morphological studyFig. 4shows the polarised light microphotographs obtained atthe end of the crystallization process for blends of MSF and PS.The fat crystal network microstructures of the blends were foundto be a mixture of various crystal morphologies. The crystals withquite different morphology were observed amongst the studiedblends. The granular structures of the crystal, similar to that ofcommercial CB were observed in Blends 1–4, having 80–95% ofMSF. The changes in the microstructures were more prominentwith the addition of PS. The large spherulitic microstructuresshowed and consisted of a needle-like periphery and a granularcentre with the addition of PS (Fig. 4a–d). Similar results forcommercial CB were reported byBrunello, McGauley, and Marangoni (2003). In another study, Toro-Vazquez, Pérez-Martínez,Dibildox-Alvarado, Charó-Alonso, and Reyes- Hernández (2004)reported that for CB crystallised at 22C, the microstructure ofthe crystals was spherulites formed by needle-like structures.4. ConclusionsIn this work, a series of blends (1–10) of MSF and PS for formulating CBRs have been prepared and examined in terms of TGcompositions, melting and crystallization profiles, SFC and morphology. The results of this study suggested that certain blendsMSF dan PS dapat digunakan untuk mempersiapkan CBRs tanpa secara signifikanmengubah sifat fisik dan kimia produk. Inicampuran terutama terdiri dari tiga TGs (POP, POS dan SOS), darikomponen TG utama CB komersial. Formulasi telahleleh dan sifat kristalisasi, khususnya onset, offset dan enthalpies mirip dengan CB komersial, meskipun merekamenunjukkan tertunda kristalisasi ke bentuk stabil. Cahaya terpolarisasimikroskop (PLM) gambar menunjukkan perubahan yang signifikan dalam kristalmorfologi dalam campuran. Formulasi yang menunjukkan yang lebih tinggiSFC di 20-25 C tidak meningkat menjadi 0% pada 37.5 C dan bergeser ke0% pada dan di atas 40 C. Campuran ini dapat digunakan untuk produksi mentega keras tahan suhu tinggi untuk negara-negara denganiklim panas. Selain itu, campuran MSF dan PS bisa memecahkantemper kesulitan untuk produsen coklat di tropis