amylose content to retrogradation [

amylose content to retrogradation [91,145,160]. For DSC measurements, in
particular, the extent of retrogradation should be greater for waxy starches
because the DSC measures the recrystallization of amylopectin [91,142,160].
It is thus safe to say that the relation between the amylose/amylopectin ratio
and retrogradation is not straightforward, as other factors are involved.
If retrogradation is to take place, the chains must first aggregate, but a
minimum requirement for the aggregation of chains to occur has been shown
to be 8 to 10 glucose units [47,176]. The short chains of amylopectin have been
shown to be responsible for crystallization in the amylopectin molecule [177],
and chains with less than 15 glucose units do not take part in the crystallization
[158,177]. If the external chains of the amylopectin molecule are removed by
β-amylolysis, no retrogradation at all occurs [178a,b]. Amylopectin from
potato, tapioca, and kuzu starches, which are B-starches, retrograde to a different extent, which has been related to differences in average chain length
[178]. Amylopectin from cereals has also been shown to retrograde to a lesser
extent than pea, potato, and canna amylopectin, which has been attributed to
shorter average chain length in the cereal amylopectin [167,173]. The length
of the external chains in the amylopectin molecule is also of relevance [178a,b].
The transition temperature, Tc, at which the melting of the recrystallized
starch occurs is nearly the same for all the cereal starches (with the exception
of amylomaize), despite differences in gelatinization temperatures of up to
24°C [171]. The gelatinized starches are fully hydrated, and the recrystallized
(retrograded) starch melts according to its melting temperature at the existing
water content. The similar Tc
values of cereal starches indicate that their
crystallites have similar stability and are therefore of similar short chain
lengths. A higher melting temperature Tchas been reported for B-starches with
longer short chains [173]. The structural differences in cereal amylopectins
related to retrogradation can be related to differences in the amorphous regions
or differences in the ratio of short chains to long chains and the ratio of A
chains to B chains. A greater amount of short chains over 15 glucose units
and an increased ratio of A chains to B chains probably promote retrogradation.
It has also been reported that very short chains (6 to 9 glucose units) can
inhibit or retard retrogradation of starch gels [179,180].
10.5 RHEOLOGICAL BEHAVIOR
OF THE STARCH GEL
The events occurring during gelatinization of a starch suspension, especially
the swelling and leaking of amylose/amylopectin, will dramatically change the
rheological properties of the starch suspension. The subsequent retrogradation
will then further modify the rheological properties. Perhaps the most common
method for studying starch properties is to study the changes in viscosity during
a programmed heating–cooking–cooling cycle. The measurements are carried

Hasil (Bahasa Indonesia) 1:

amylose content to retrogradation [91,145,160]. For DSC measurements, inparticular, the extent of retrogradation should be greater for waxy starchesbecause the DSC measures the recrystallization of amylopectin [91,142,160].It is thus safe to say that the relation between the amylose/amylopectin ratioand retrogradation is not straightforward, as other factors are involved.If retrogradation is to take place, the chains must first aggregate, but aminimum requirement for the aggregation of chains to occur has been shownto be 8 to 10 glucose units [47,176]. The short chains of amylopectin have beenshown to be responsible for crystallization in the amylopectin molecule [177],and chains with less than 15 glucose units do not take part in the crystallization[158,177]. If the external chains of the amylopectin molecule are removed byβ-amylolysis, no retrogradation at all occurs [178a,b]. Amylopectin frompotato, tapioca, and kuzu starches, which are B-starches, retrograde to a different extent, which has been related to differences in average chain length[178]. Amylopectin from cereals has also been shown to retrograde to a lesserextent than pea, potato, and canna amylopectin, which has been attributed toshorter average chain length in the cereal amylopectin [167,173]. The lengthof the external chains in the amylopectin molecule is also of relevance [178a,b].The transition temperature, Tc, at which the melting of the recrystallizedPati terjadi hampir sama untuk semua Pati sereal (dengan pengecualiandari amylomaize), meskipun perbedaan dalam gelatinization suhu hingga24° C [171]. Pati gelatinized sepenuhnya terhidrasi, dan recrystallizedPati (akan mundur) meleleh sesuai dengan suhu mencair di yang adakadar air. Tc serupanilai-nilai sereal Pati menunjukkan bahwa merekacrystallites memiliki stabilitas serupa dan karena itu rantai pendek yang serupapanjang. Temperatur leleh lebih tinggi Tchas telah dilaporkan untuk B-Pati denganpanjang rantai pendek [173]. Perbedaan struktural sereal amylopectinsterkait dengan retrogradation dapat terkait dengan perbedaan di daerah amorfatau perbedaan dalam rasio rantai pendek panjang rantai dan rasio arantai untuk B rantai. Sejumlah besar singkat rantai lebih dari 15 unit glukosadan meningkatnya rasio rantai untuk B rantai mungkin mempromosikan retrogradation.Juga telah dilaporkan bahwa dapat sangat singkat rantai (6-9 glukosa unit)menghambat atau menghambat retrogradation Pati gel [179,180].10,5 RHEOLOGICAL PERILAKU GEL PATIPeristiwa-peristiwa yang terjadi selama gelatinization dari Pati suspensi, terutamapembengkakan dan bocornya amilosa/amilopektin, secara dramatis akan berubahrheological pada penangguhan Pati. Retrogradation berikutnyaakan kemudian lebih lanjut memodifikasi rheological pada. Mungkin yang paling umummethod for studying starch properties is to study the changes in viscosity duringa programmed heating–cooking–cooling cycle. The measurements are carried

Hasil (Bahasa Indonesia) 2:

kadar amilosa untuk retrogradasi [91145160]. Untuk pengukuran DSC, di
khususnya, tingkat retrogradasi harus lebih besar untuk pati lilin
karena DSC mengukur rekristalisasi dari amilopektin [91142160].
Dengan demikian dapat dikatakan bahwa hubungan antara amilosa / amilopektin rasio
dan retrogradasi tidak langsung, faktor-faktor lain yang terlibat.
Jika retrogradasi adalah untuk mengambil tempat, rantai harus agregat pertama, tetapi
persyaratan minimum untuk agregasi rantai terjadi telah terbukti
menjadi 8 sampai 10 unit glukosa [47176]. Rantai pendek amilopektin telah
terbukti bertanggung jawab atas kristalisasi dalam amilopektin molekul [177],
dan rantai dengan kurang dari 15 unit glukosa tidak mengambil bagian dalam kristalisasi
[158177]. Jika rantai eksternal molekul amilopektin dikeluarkan oleh
β-amylolysis, tidak ada retrogradasi sama sekali terjadi [178a, b]. Amilopektin dari
kentang, tapioka, dan pati kuzu, yang B-pati, retrograde sampai batas yang berbeda, yang telah berhubungan dengan perbedaan rata-rata panjang rantai
[178]. Amilopektin dari sereal juga telah ditunjukkan untuk retrograde ke yang lebih rendah
sejauh daripada kacang, kentang, dan amilopektin ganyong, yang telah dikaitkan dengan
rata-rata panjang rantai lebih pendek dalam sereal amilopektin [167173]. Panjang
rantai eksternal dalam molekul amilopektin juga relevansi [178a, b].
Suhu transisi, Tc, di mana mencairnya rekristalisasi
pati terjadi hampir sama untuk semua pati sereal (dengan pengecualian
dari amylomaize ), meskipun perbedaan suhu gelatinisasi hingga
24 ° C [171]. Pati yang gelatinized sepenuhnya terhidrasi, dan rekristalisasi
(retrograded) pati meleleh sesuai dengan suhu leleh di ada
kadar air. Tc serupa
nilai pati sereal menunjukkan bahwa mereka
kristalit memiliki stabilitas yang sama dan karena itu rantai pendek yang sama
panjang. Sebuah lebur yang lebih tinggi Tchas suhu dilaporkan untuk B-pati dengan
rantai pendek lagi [173]. Perbedaan struktural dalam amylopectins sereal
yang berhubungan dengan retrogradasi dapat dikaitkan dengan perbedaan di daerah amorf
atau perbedaan rasio rantai pendek rantai panjang dan rasio A
rantai untuk rantai B. Dalam jumlah lebih besar dari rantai pendek lebih dari 15 unit glukosa
dan rasio meningkat dari A ke B rantai rantai mungkin mempromosikan retrogradasi.
Ini juga telah melaporkan bahwa rantai yang sangat singkat (6 sampai 9 unit glukosa) dapat
menghambat atau memperlambat retrogradasi pati gel [179180 ].
10,5 rheologi PERILAKU
DARI PATI GEL
Peristiwa yang terjadi selama gelatinisasi suspensi pati, terutama
pembengkakan dan bocornya amilosa / amilopektin, akan secara dramatis mengubah
sifat reologi dari suspensi pati. The retrogradasi berikutnya
maka akan lebih memodifikasi sifat reologi. Mungkin yang paling umum
metode untuk mempelajari sifat pati adalah untuk mempelajari perubahan viskositas selama
siklus pemanasan-memasak-pendinginan diprogram. Pengukuran dilakukan