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1. Tesis adalah hakmilik Universiti Malaysia Sabah. 2. Perpustakaan Universiti Malaysia Sabah dibenarkan membuat salinan untuk tujuan pengajian sah~a. 3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi pengajian tinggi. 4. ** Sila tandakan ( / )

(Mengandungi maklumat yang berdarjah keseJamatan ' atau kepentingan Malaysia seperti yang termaktub di

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(Mengandungi maklumat TERHAD yang telah ditentukakan TERHAD oleb organisasilbadan di man~ penyelidikan dijalankan)

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rAT AN: * Potong yang tidak berkenaan. * Jika tesis ini SULIT atau TERHAD, sila lampiran surat daripada pihak berkuasa/organsasi

berkenaan dengan menyatakan sekali sebab dan tempoh tesis ini perlu dikelaskan sebagai SUUT dan TERHAD.

* Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah dan Sarjana secara penyelidikan, atau disertasi b,agi pengajian seeara kerja kursus dan penyelidikan, atau Laporan Projek Sarjana Muda (LPSM).

EFFECT OF pH ON PHYSICOCHEMICAL

CHARACTERISTICS OF THREE TYPES OF MODIFIED GCWS SAGO STARCH.

TONG WOON SHENG

THIS DISSERTATION IS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENT FOR THE

DEGREE OF FOOD SCIENCE WITH HONOURS IN FOOD SCIENCE AND NUTRITION

SCHOOL OF FOOD SCIENCE AND NUTRITION UNIVERSITI MALAYSIA SABAH

2010

DECLARATION

I hereby declare that the work in this thesis is my own except for quotations and summaries which have been duly acknowledge.

16 Apr 2010

ii

NAME

MATRIC NO.

TITLE

DEGREE

DATE OF VIVA

1. SUPERVISOR (DR LEE JAU SHYA)

2. EXAMINER 1

VERIFICATION

: TONG WOON SHENG

: HN2006-3623

: EFFECT OF pH ON PHYSICOCHEMICAL CHARACTERlsrICS OF THRESS TYPES OF MODIFIED GCWS.

: BACHELOR OF FOOD SCIENCE HONORS

: 14 MAY 2010

CERnFIEDBY

Signature

~. (ASSOC. PROF. DR. MOHO. ISMAIL ABDULLAH)

3. EXAMINER 2 (DR. MOHO ROSNI SULAIMAN)

4. DEAN

(ASSOC. PROF. DR. MOHO ISMAIL ABDULLAH)

iii

ACKNOWLEDGEMENT

First and foremost, I would like to express my deepest gratitude and appreciation to my supervisor, Dr Lee Jau Shya for all her guidance, advices, and support in this research work that had greatly helped me to complete this thesis. Her untiring patience to guide me and her constructive advices had allowed me to learn so many things and at the same time apply it in this research work. I would like to thank Teoh Han Boon for his advices on methods that could be applied carry out this research. Besides that, I must thank Lim Koon Eaik, Matthew Tan Chee Siang, Leong Kean Kee and Oon Xin Van for their support and time they had sacrificed to help me complete this thesis. To my family, course mates and friends, a million thanks to them for their cheers and support throughout my time spent in completing this thesis. Their relentless support had made this research possible. Last but not least, to everyone that had supported and helped me directly or indirectly in making completing this thesis, I express my sincerest gratitude to them. Thank you .

•

iv

ABSTRACT

This study is to investigate the effect of pH on cold water solubililty, swelling ratio,

spreadability, morphological and rheological dynamic properties of three types

(hydroxypropylation, cross-linking, dual modification) of modified GONS (Granular Cold

Water Soluble) sago starch. These three chemical modifications were combined with

alcoholic-alkaline treatment to produce chemical modified GONS. The physicochemical

characteristics were evaluated at pH 2 to pH 9. All modified GONS samples exhibited

good solubility (>50%) across pH 2 to 9. Cold water solubility was found decrease as

pH increased, while cold water swelling ratio, spreadability dynamic rheological

properties was found increased as pH increased. All modified samples were found to

be more solid-like dispersion with G' value higher than Gil value. Though

hydroyxpropyalted, H sample showed similar cold water solubility and swelling ratio

(p>0.05) as compared to the control sample; while lower spreadability and G' and Gil

value (p<O.OS). DM2 was found to have similar (p>O.OS) cold water solubility and

spreadability as H sample. However, the low degree of cross-linking resulted the

swelling ratiO, G' and Gil value of DM2 to be higher (p<0.05) than the control. Hand

DM2 were found rupture with fragmentation across whole pH range like the control

sample. The high degree of cross-linking in DMl caused it to have lowest cold water

solubility, swelling ratio, spreadability, G' and Gil value (p<0.05) among all modified

samples. On the other hand, the mildly cross-linking in CL brought higher swelling ratio,

spreadability, G' and Gil value (p<0.05) as compared to its control. Both DMl and CL

sample were able to retain their granularity throughout pH 2 to 9.

v

A BSTRAK

EFFECT OF pH ON PHYSICOCHEMICAL CHARACTERISTICS OF THREE TYPES

MODIFIED GCWS SAGO STARCH.

Kajian ini dijalankan untuk menyiasat kesan pH terhadap keterlarutan air sejuk,

pembengkakan air sejuk, kebolehsapuan, ciri-ciri morf%gi dan sifat dinanik rhe%gi

atas tiga jenis kanji GCWS terubah-suai (hidrosipropi/as~ paut-si/ang, dwi modifikasi).

Tiga jenis modifikasi telah dikenakan ke atas kanji sago sebe/um rawatan a/kohol-a/kali

untuk menghasi/kan kanji GCWS terubah-suai. Ciri-ciri fisikokimia te/ah diperhatikan

pada pH 2 hingga 9. Setiap kanji GCWS terubah-suai mencapai keterlarutan >50%

pada pH 2 hingga 9. Keterlarutan didapati menurun apabi/a pH meningkat.

Pembengkakan kebolehsapuan dan sifat dinamik rhe%gi didapati meningkat apabila

pH meningkat Semua ampaian kanji GCWS didapati /ebih bersifat pepeja/ dengan ni/ai

G' me/ebihi G'~ Wa/aupun dihidripropi/asikan, keterlarutan sampe/ H didapati sama

(p>0.05) dengan sampe/ kawa/annya; sementara kebo/ehsapuan, ni/ai G' dan G"

dipapati /ebih rendah (p<0.05) daripada kawa/annya. OM2 didapati mempunyai

keterlarutan dan kebo/ehsapuan yang sama (p>0.05) dengan sampe/ H. Wa/au

bagaimanapun, tahap paut-si/ang yang rendah pada OM2 mengakibatkan

pembengkaan, ni/ai G' dan G" /ebih tinggi (p<0.05) daripada sampe/ kawa/annya.

Sampe/ H dan OM2 didapati pecah dengan sepihan keci/ pada ju/at pH 2 hingga 9.

Pemerhatian yang sama juga didapati pada sampe/ kawa/annya. Tahap paut-si/ang

yang tiggi da/am sampe/ OM1, menyebabkannya mencapai keterlarutan,

pembengkaaan, kebo/ehsapuan, ni/ai G'dan G" yang paling rendah (p<0.05) antara

semua sampel. Seba/iknya, tahap paut-si/ang yang serderhana pada CL didapati

meningkatkan pembengkaan, kebo/ehsapuan, ni/ai G' dan G'" berbanding sampe/

kawa/annya. Kedua-dua OM1 dan CL didapati mampu mengekalkan kesempurnaan

granu/ da/am julat pH 2 hingga 9.

vi

TITLE DECLARATION VERIFICATION ACKNOLEDGEMENT ABSTRACT ABSTRAK TABLE OF CONTENT LIST OF FIGURE LIST OF TABLE LIST OF ABBREVIATION LIST OF SYMBOL LIST OF APPENDIX

CHAPTER 1: INTRODUCTION

1.1 Background of studies 1.2 Rationale 1.3 Objective

CHAPTER 2: LITERATURE REVIEW

CONTENT

PAGES

ii iii iv v vi vii ix xi xii xiii xiv

1 4 5

2.1 Sago starch 6 2.1.1 Structure and organization 7 2.1.2 Characterization of sago starch 9 2.1.3 Application and market potential 10

2.2 Pregelatinized starch 11 2.2.1 Texturized pregelatinized starch 14 2.2.2 Granular Cold water swelling/soluble starch (GCWS) 17 2.2.3 Modified Granular Cold water soluble starch 19 2.2.4 Application 21

2.3 Chemical modification 22 2.3.1 Hydrpxypropylation 26 2.3.2 Crosslinked 28 2.3.3 Dual modification 30

2.4 pH effect on starch 32 2.4.1 Acidic 32 2.4.2 Alkaline 33

CHAPTER 3: METHODOLOGY

3.1 Materials 3.2 Study design

vii

34 34

3.3 Dual modification 35 3.4 Crosslinked 36 3.5 Hydroxypropylation 36 3.6 Alcoholic-alkaline treatment 37 3.7 Moisture content determination 37 3.8 Phosphorus content 38 3.9 Molar substitution (MS) 38 3.10 pH 39 3.11 Ash content 39 3.12 Buffer solution preparation 40 3.13 Cold water solubility 41 3.14 Cold water Swelling ratio 41 3.15 Spreadability 42 3.16 Morphological study 42 3.17 Statistic analysis 43

CHAPTER 4: RESULT AND DISCUSSION

4.1 Moisture content 44 4.2 Phosphorus content 45 4.3 Molar substitution (MS) 45 4.4 Ash content 46 4.5 pH 47 4.6 Cold water solubility 48 4.7 Cold water swelling ratio 53 4.8 Spreadability 58 4.9 Morphological study 63 4.10 Dyanamic rheological behavior 72

CHAPTER 5: CONCLUSION AND SUGGESTION

5.1 Conclusion 79 5.2 Suggestion 81

REFERENCES 82 APPENDIX 96

viii

LIST OF FIGURES

Figure 2.1: a- 1, 4, linkages of amylose 12

Figure 2.2: Amylopectin 12

Figure 2.3 Hydroxypropylation reaction of starch with propylene oxide 28

Figure 2.4: Crosslinking of starch with STMP 31

Figure 4.1: Cold water solubility of modified GCWS sago starch samples from 53 pH 2 to 9.

Figure 4.2: Cold water swelling ratio of of modified GONS sago starch samples 58

from pH 2 to 9.

Figure 4.3: Spreadability of of modified GONS sago starch samples from pH 2 63 to 9.9

Figure 4.4: Light microscope micrographs of CL sample under 400x 65 magnification in pH 2 to pH 9

Figure 4.5: Light microscope micrographs of H sample under 400x 66 magnification in pH 2 to pH 9

Figure 4.6: Light microscope micrographs of OM1 sample under 400x 67 magnification in pH 2 to pH 9

Figure 4.7: Light microscope micrographs of OM2 sample under 400x 68 magnification in pH 2 to pH 9

Figure 4.8: Light microscope micrographs of C2 sample under 400x 71 magnification in pH 2 to pH 9

Figure 4.9: Light microscope micrographs of CL sample under 400x 72 magnification in pH 2 to pH 9.

ix

Figure 4.10: Storage modulus (G') of modified GCWS sago starch samples from 77

pH 2 to 9.

Figure 4.11: Loss modulus (G") of modified GCWS sago starch samples from pH 78

2 to 9.

x

LIST OF TABLES

Table 2.1: Chemical composition of sago starch 9

Table 2.2: Types of starch modification and its preparation 25

Table 2.3: Properties and application of modified starch 26

Table 3.1: Sample Preparation 36

Table 3.2: Buffer solution reagent 42

Table 4.1: Moisture content of modified starch 44

Table 4.2: Phosphorus content of chemical modified starch 45

Table 4.3: Molar substitution of chemical modified starch 46

Table 4.4: Ash content of respective chemical treated GCWS 47

Table 4.5: pH of alcoholic alkaline treated modified samples 47

Table 4.6: Cold water solubility of modified GCWS sago starch samples from 49

pH 2 to 9.

Table 4.7: Cold water swelling ratio of modified GCWS sago starch samples 55

from pH 2 to 9.

Table 4.8: Spreadability of modified GCWS sago starch samples from pH 2 to 60

9.

Table 4.9: Storage modulus (G')* of modified GCWS sago starch samples from 73

pH 2 to 9.

Table 4.10: Loss modulus (G")* of modified GCWS sago starch samples from 74

pH 2 to 9.

xi

GCWS NaOH HCI v/v w/v M STPP STMP EPI DM CL H DS MS DSC RVA SEM NaCi N2S04

POCb

LIST OF ABBREVIATIONS

Granular Cold water soluble/swelling Sodium hydroxide Hydrochloric acid Volume of solute in the total volume of solution Weight of solute in the total volume of solution Molar solution Sodium Tripolyphosphate Sodium Trimetaphosphate Epichorohydrin Dual modification Crosslinking Hydroxypropylation Degree substitution Molar substitution Differential scanning calorimetry Rapid Visco Analyser Scanning electron microscopy Sodium Chloride Nitrogen Sulfate Phosphoryl Chloride

xii

k/cm3

mLjg IJm Sjm °c mL rpm g L Mg % Hr M

LIST OF SYMBOLS

Intensity of light Viscosity Micrometer Salinity Degree Celcius Milliliter Revolution per minute gram liter milligram Percentage hour Molar

xiii

LIST OF APPENDIXS

Appendix A One way anova on moisture content for different chemical 96 modified samples

Appendix B One way anova on moisture content for different chemical 97 modified GONS samples

Appendix C One way anova on phosphorus content for different chemical 98 modified GONS samples

Appendix D One way anova on MS for different chemical treated samples 99

Appendix E One way anova on ash content for different chemical modified 100 GONS samples

Appendix F One way anova on pH value for different chemical modified GONS 101 samples

Appendix G One way anova on cold water solubility for chemical modified 102 GONS C1, H, DM1 and DM2 samples in different pH

Appendix H Pair t-test on solubility for chemical modified GONS C2 and CL 108 samples in different pH

Appendix I One way anova on cold water swelling for chemical modified 112 GONS C1, H, DM1 and DM2 samples in different pH

Appendix] Pair t-test on cold water swelling for chemical modified GONS C2 118 and CL samples in different pH

Appendix K One way anova on spreadability for chemical modified GONS C1, 121 H, DM1 and DM2 samples in different pH

Appendix L Pair t-test on spreadability for chemical modified GONS C2 and CL 127 samples in different pH

Appendix M One way anova on storage modulus for chemical modified GCWS 130 Cl f H, DM1 and DM2 samples in different pH

Appendix N Pair t-test on storage for chemical modified GONS C2 and CL 143 samples in different pH

xiv

CHAPTER 1

INTRODUCTION

1.1 Background of the study

Pregelatinized starch is a type of starch that is able to swell instantly without forming

any lump and without heating it to have thickening effect (Vaclaik and Christian, 2008).

Basically there are two types of pregelatinized starch namely the granular cold water

swelling starch (GCWS starch) and texturized pregelatinized starch (David and William,

1999). The difference between these two types of starch is that cold water swelling

starch granule does not experience rupture, whereas texturized pregelatinized starch

granule will rupture after treated with pregelatinized treatment (Zhao, 2007).

Pregelatinized starch is widely used in instant food such as soups, puddings, jellies, pie

fillings, instant dry mix desserts, sauces, and whipped toppings (Klingler et al., 2006) .

Pregelatinized starch can be prepared by various methods, such as drum drying

(O'Rourke, 1980), extrusion (Cheng et al., 1977), spray drying (Picheon et al., 1981),

alcoholic treatment with high temperature or pressure treatment (Eastman et aI., 1984;

Rajagopalan and Seib, 1992), and alcoholic-alkaline treatment (Jane and Seib, 1991).

Comparison between conventional treated pregelatinized starches and cook up starch

showed that there are differences in texture and solubility. Due to the ruptured granule,

pregelatinized starch would cause problems such as graininess, less sheen and less

flexibility towards processing condition. Consequently, the textures of instant foods

made with pregelatinized starch cannot be matched in terms of quality compared to

cook up starch (Chen and Jane, 1994a). Thus, further improvement was carried out in

order to improve the solubility of the starch while maintaining the granularity of starch.

Such improvement method is known as alcoholic-alkaline treatment. The treated starch

1

swells due to the reaction of starch granule with the alkaline reaction and the degree

of swelling is controlled by alcohol (Chen and Jane, 1994b). Alcoholic alkaline treated

starch is able to achieve cold water solubility from 50% to 94% (Jane and Seib, 1991).

Previous studies showed that alcoholic alkaline treatment was affected by

various factors such as temperature, concentration of sodium hydroxide and ethanol.

Treatment at a lesser concentration of ethanol with a greater concentration of sodium

hydroxide and a higher reaction temperature was able to produce GONS starches with

greater cold water solubility (Chen and Jane, 1994a). Further effort on optimization of

alcoholic-alkaline treatment on sago starch has identified the optimum condition as

40.7% - 50.5% ethanol and 278.5 - 296.3g sodium hydroxide (Lee et al., 2008). The

treated starch under the optimum condition was able to achieved 52.2% cold water

solubility, with particle size 25.4lJm and retained starch granule. High concentration of

sodium hydroxide is able to increase the amylose leaching. On the other hand,

excessive sodium hydroxide causes the starch granules to rupture (Lee et al., 2008).

In order to reinforce starch granular structure and increase solubility and

swelling of the GONS starch, attempts was carried out by combining chemical

modification such as crosslinking, hydroxypropylation or dual modification prior to

alcoholic-alkaline treatment (Teoh, 2009; Lee et aI., 2009; Yap, 2009). Teoh (2009)

produced hydroxypropylated GONS sago starch by mixing native sago starch with 8%

hydrxypropylation reagent followed by NaOH:Starch ratio 3:1 and 50 % ethanol with

75.15 % cold water solubility. Hydroxypropylation is a substitution reaction of starch

where starch is reacted with propylene oxide to form the hydroxypropyl starch which

improves the freeze thaw stability, clarity and textural properties of the starch paste

(Aziz et al., 2004). Studies showed that the hydroxypropylation weakens the bonding

between starch molecules and allows it to swell more readily and more soluble (Lawai

et al., 2008). Hydroxypropylation prevents retrogradation, resulting in more fluid paste

with improved paste clarity resulting in a product with desired textural properties

2

(Singhal, 2008). The maximum permitted concentration of hydroxpropylation reagent

to be use in hydropropylation reaction is 25 % (FDA, 2009).

Yap (2009) produced cross-linked GDNS sago starch that was able to achieve

cold water solubility higher than 60% while retaining granularity. Study found that the

mixture of phosphate salts sodium trimetaphosphate (STMP) and sodium

tripolyphosphate (STPP) is more efficient than other cross-linking reagent

(Wattanachant et aI., 2003). Combination treatment of 0.05 % STMP: STPP, 60 %

ethanol and NaOH:starch 3:1 had been suggested to achieve highest cold water

solubility of 66.2% without rupturing the starch granules (Yap, 2009). Cross-linking

was chosen to modify the starch before alcoholic-alkaline treatment as it is able to

tolerate higher temperature, higher shear and more acidic conditions (Yoneya et a/.,

2003). Cross-linking starch is one of the chemical modification techniques by reacting

two or more different hydroxyl groups of the native starch with bi or poly-functional

chemical reagent (David and William, 1999). The cross-linking reagent reacts and bond

covalently with the granular structure to strengthen it (Acquarone and Rao, 2003).

Apart from that, cross linked starch would show reduction of paste clarity and

improvement in pasting properties (Dumitriu, 2005). The extent of cross-linked starch

is able to be verified by the phosphorus content (Deetae, 2008). The maximum

permitted concentration of cross-linking reagent should not exceed 0.4% (FDA, 2009).

From previous study, it is found that two combinations of dual modified GDNS

sago starch was able to achieve cold water solubility that is higher than 60 % while

maintaining starch granule (Pang, 2009). These combinations are 0.07 % cross linking

reagent and 9 % hydroxypropylation reagent, as well as combination 0.08 % cross

linking reagent and 7 % hydroxypropylation reagent. The treated starch was reacted

by 50 % ethanol and NaOH : Starch 1:3 (Pang, 2009).

Dual modification was suggested to be carried out before alcoholic-alkaline

treatment because dual modification could improve physiochemical characteristics of

3

starch. Previous study found that dual modification was able to improve freeze-thaw

stability of rice starch (Deetae et aI., 2008). Besides that, the dual modified sago

starch was showed no viscosity breakdown and no significant difference in pasting

characteristics when applied in different pH condition (Wattanachant et aI., 2002b).

1.2 Rationale

This study is a continuous effort to further characterize the properties of the modified

GCWS sago starch which consists of combination of chemical modification (dual

modification, cross-linking and hydroxypropylation) and alcoholic-alkaline treatment

that was carried out in the laboratory previously. Studies on cold water solubility and

starch microscopic structure of modified GONS sago starch were done previously

(Pang 2009; Teoh, 2009; Yap, 2009).

GCWS starch has been widely used in various types of food systems which can

be acidic or alkaline. Based on FDA (2009), pH of the common foods are in the range

of pH 2 to 9. For instance, pregelatinized starch was used in production of reduced fat

cream cheese which was coagulated in the mild acidic condition. Cream cheese is

usually stored under refrigerated condition (Finocchiaro, 1997). Cream cheese usually

have the pH value of 4.10 - 4.79 (FDA, 2007). GONS starch also has been applied in

instant pudding (O'Rouke, 1980). The pH value of lime flavor pudding can be as low as

2.60 (FDA, 2007). Besides that, modified GONS starch also has potential to be applied

with egg to produce custard, and egg usually has pH value of 8 (FDA, 2007). Thus it is

important to understand the behavior of the modified GONS starch in the range of pH

2 to 9. Wattanachant et al. (2002b) found that chemical modified starch was able to

resist wide range of pH. However, there is no any study on pH effect towards

physicochemical properties of these modified GONS starch. The result of the study

allows us to determine suitability of modified GCWS sago starch in the potential

industrial processing condition and food system which could be either acidic or alkaline.

4

Based on the earlier studies, different chemical modified starch have different

characteristics. For instances, cross-linked starch would have higher stability towards

swelling, heat shear and acidic condition (Yoneya et at., 2003). The hydroxypropylated

starch would have improved clarity of starch paste, greater viscosity, reduced syneresis

and freeze-thaw stability (Wu and Seib, 1990). Mean while, dual modified reaction is

able to improve paste consistency, smoothness and freeze-thaw stabilities (Sing et at.,

2007). Therefore, we anticipated different chemical modified GCWS starch would

behave differently when compared to GCWS sago starch that was solely produced by

alcoholic-alkaline treatment.

In Malaysia, sago palm is inexpensive and not agriculturally intensive as rice.

Presently, commercial production of sago flour in Malaysia occurs mainly in Sarawak

and small parts of Johor. In Sarawak, the planting area of sago is estimated above

50, 000 hectare which is the fourth largest area for crops in Sarawak. Sarawak is also

one of the biggest exporters of sago. Sago brings above RM50 million in exports

earning in latest year for Sarawak (Aziz, 2002; DOA, 2009). This value is expected to

rise in coming year, therefore by understanding the new application of sago starch it

would able to boost up the starch industry by diversify the usage of sago starch and

increase the value of the sago starch.

1.3 Objective

To study the effect of pH on cold water solubililty, cold water swelling, spreadability,

morphological study and rheological dynamic properties of three types

(hydroxypropylation, cross-linking, dual modification) of modified GCWS (Granular cold

water soluble) sago starch.

5

CHAPTER 2

LITERATURE REVIEW

2.1 Sago starch

Sago starch is extracted from the sago palm which is a hepaxanthy (once flowering),

monocotyledonous plant which belongs to the species of the genus Metroxylon sub

family of Calamoideae, and family of Palmae. Sago palms usually are 6-14m tall and

hapaxantic which mean the sago palm will die after it flowered once (Singhal et al.,

2008). The extraction of sago starch usually can be done in two methods which are

the traditional method and the modern method (Karim et al., 2008; Nishimura and

Laufa, 2002).

The traditional extraction usually involves four major processes which start with

harvested mature sago palm. It follows by cutting sago palm into partitioned logs.

Followed by pounding or crushing of the sago pith and lastly is the washing of sago

piths for starch extraction (Nishimura and Laufa, 2002). The fibrous pith will be rasped

by a sharpened piece of hardwood. The rasped pith will mix with water and streams

through the sieve, to filter the fibre out. The starch will settles on the bottom of the

vessel (Flach, 1997).

The modern extraction is more or less similar to the traditional method which it

involve machinery and able to extract in a bigger scale. The bark of the sago palm was

removed and the debarked section will be fed into the mechanical rasper to rasp the

pith into finer pieces. The rasped product will mix with water and form starch slurry to

pass through series of centrifugal sieves to separate the coarse fibres. The further

6

purification was done by using nozzle separator through sieve bends and a series of

cyclone separators to produce very pure starch (Singhal et al., 2008).

The sago palm usually grow optimally under humid tropical lowlands which at

the altitude of 700m and the temperature of the environment of 25°C, relative air

humidity of 70%, the inditental light 800 k/cm2 per day and salinity should not exceed

1/8 of the salt concentration of the sea water. These are the optimum conditions for

sago palm to grow. Therefore sago starch commonly can be found in countries such

as Malaysia, Indonesia and Papua New Guinea (Aziz, 2002).

The starch granule are made up by two major type of polymer which known as

amylose and amylopectin. There are some other minor constituents such as lipids,

proteins, phosphate and ash which it did playa role in affect the functional properties

of the starch in starch application (David and William, 1999). Sago starch is different

compare to other types of starch by its size of granule, swelling power, gelatinization,

retrogradation and the synerisis of the starch (Wattanachant et al., 2002).

2.1.1 Structure and organisation

Sago starch contains 27% amylase and 73% amylopectin, in its polymer structure. The

amylose and amylopectin moelecules was arranged readily and made up starch

granules which contain crystalline and non crystalline regions in alternating layers

(Fennema, 1996). The amylose content of the sago starch is higher if the starch is

extracted from the upper part of the lower part of the trunk compare to the starch that

is extracted from the upper part of the trunk (Tomoko et al., 2000). The grain size

distribution of sago starch is about 16 - 25.4l.Jm. The grain size will increase up to 40

I.Jm as the age of the trunk getting old until initiation of the inflorescence. The sago

starch had bigger average granule size compared to other starch bases such as waxy

maize, waxy barley, tapioca, wheat, corn and rice (Satin, 2000). The molecular weight

for amylose is ranged between 1.41 x 106 - 2.23 X 106 and the amylopectin molecular

weight is 6.70 x 106 - 9.23 X 106 (Colonna et aI., 1984); (Roger et aI., 1993). The

7

chemical composition of sago starch can be shown in Table 2.1. The amylose and

amylopectin ratio play important role in affecting the viscosity, shear resistance,

gelatinization, textures, solubility, tackiness, gel stability, cold swelling and

retrogradation of the starch (Satin, 2000).

Table 2.1: Chemical composition of sago starch

Constituent Amylose Amylopectin Lipids Portein Ash

Dry weight basis (0/0) 27 73 0.1 0.1 0.2

Phosphorus 0.02 Source: (Singhal et al., 2008)

Amylose is one of the essential linear polymer compose made up almost the

whole a- 1,4 linked D-glucopyranose (Fennema, 1996). The simplified amylose polymer

can be shown as in Figure 2.1. Usually amylose exist in long helical structure which it

have molecular weight about 1.41 x 106 - 2.23 X 106 (Karim et a/., 2008). The interior

of the helix structure contains hydrogen atoms which are hydrophobic; the exterior of

the helix structure consists of hydroxyl groups (David and William, 1999). The amylase

forms a 3-dimensional network when the molecules associate upon cooling which this

phenomenon responsible for the gelatinization of the starch pastes (Vaclaik & Christian,

2008).

8

OH OH

Figure 2.1: a- 1, 4, linkages of amylose

Source: (David and William, 1999)

300-6000H

Amylopectin is the major component of starch (comprising 70-80%) and is a

much larger branched molecule in which about 5% of the glucose units are joined by

al-6 linkages (Jobling, 2004). The structure of amylopectin can be shown as in Figure

2.2. The higly branched amylopectin will packed together in the form of double helices

and it forms many small crystalline areas containing the dense layers of starch

granules and alternate with less dense amorphous layers (Fennema, 1996).

o a

Amylopectin: a·( 1~) branching points. For exterior chains a = ca. 12·23. For interior chains b = ca. 20 . 30. Both a and b vary according to the botanical origin.

Figure 2.2: Amylopectin

Source: (Tester, Karkalas and Qi, 2004)

0-

9

References

Acquarone V. M.~ and Rao M., A., 2003. Influ~nce of suc~ose on the rheology and granule sIze of cross-linked waxy maIze starch dIspersions heated at two temperatures. Carbohydate Polymers. 51: 451-458.

Adebowale K.O., Henle T., Schwarzenbo/z U., and Doert T. 2009. Modification and properties of African yam bean (Sphenostylis stenocarpa Hochst. Ex A. Rich.) Harms starch I: Heat moisture treatments and annealing. Food Hydrocol/oids. 23: 1947-1957.

Ahmed J., Ramaswamy H. S., Ayad A., and Alii I. 2008. Thermal and dynamic rheology of insoluble starch from basmati rice. Food hydroco//oids. 22: 278-287.

Alam F., and Hasnain A., 2009. Studies on swelling and solubility of modified starch from taro (Colocasia escu/enta): Effect of pH and Temperature. Agriculturae conspectus scientificus. 74: 45 - 50.

AOAC (1984). Official methods of analysis: Phosphorus in flour. Arlington. USA: Association of Official Analytical Chemistry. 251.

AOAC (1990). Official methods of analysis: Moisture and ash. Arlington. USA: Association of Official Analytical Chemistry. 777.

Aziz A., Daik R., Ghani M., A., Daud N. I. N., and Yamin B. M. 2004. Hydroxypropylation and acetylation of sago starch. Malaysian Journal of chemistry. 1: 48 - 54.

Aziz S. A., 2002. Sago starch and its utilization. Journal of bioscience and bioengineering. 94(6): 526 - 529.

Bagley E. B., and Christianson D. D. 1982. Swelling capacity of starch and its relationship to suspension viscosity - effect of cookin time, temperature and concentration. Journal of texture studies. 13: 115 - 126.

82

Bandaru V. V. R., Somalanka S. R., Mendu D. R., Madicherla N. R., and Chityal a A., 2006. Optimization of fermentation conditions for the production of ethanol from sago starch by co-immobilized amyloglucosidase and cells of Zymomonas mobilis using response surface methodology, Enzyme and Microbial Technology. 38: 209-214

Barbosa-Canovas G. V., Ortega-Rivas E., Juliano P., and Van H., 2005. Food powders: physical properties, processing and functionality. New York: Kluwer academic/ Plenum Publisher.

Barsby T. L., Donald A. M., and Frazier P. J. 2001. Starch: Advances in structure and function. UK: The Royal Society of Chemistry.

Bello-Perez L. A., Manilla R. R., and Irapuato P. P. L. 2000. Preparation and properties of physically modified Banana starch by alcoholic-alkaline treatment. Starch/starke. 52: 154-159.

BeMiller J. N., and Whistler R. L. 2009. Starch: Chemistry and Technology. 2nd

edition, U.K: Elsevier Inc.

Blaszczak W., Valverde 5., and Fornal J. 2005. Effect of high pressure on the structure of potato starch, Carbohydrate Polymers. 59: 377 - 383

Chang Y. H., Un J. H., and Ui C. Y. 2004. Effect of ethanol concentration on the physicochemical properties of waxy corn starch treated by hydrochloric acid. Carbohydrate Polymers. 57(1): 89 - 96.

Chang Y. H., Un J. H., and Pan C. L., 2010, Type and concentration of acid on solubility and molevular size of acid-methanol-treated rice starches differing in amylose content, Carbohydrate Polymers, 79(3): 762 -768.

Chen J. and Jane J: 1994a. Preparation of granular cold water soluble starches alcoholic-alkaline treatment. Cereal Chem 71(6): 618 - 622

Chen J. and Jane J. 1994b. Properties of Granular Cold-Water-Soluble Starches Prepared by Alcoholic-Alkaline Treatments. Cereal Chem. 71(6): 623-626

Cheng H., and Huebner W. S. 1997. Extruted starch product for tapioca-style pudding. U.S. 4,025,657.

83

Cheng H., and Wintersdroff P. 1981. Xanthan Gum modified starches. U.S. Patent 4,298,729.

Chiu C. W., and Rutenberg M. W. 1980. Cold water dispersible, Gelling starch. U.S. Patent 4,229,489.

Chung H. J., and Hoover R, Liu Q. 2009. The impact of single and dual hydrothermal modifications on the molecular structure and physicochemical properties of normal corn starch, International Journal of biological macromolecules44: 203-210.

Colonna, P. and Mercier C. 1984. Macromolecular structure of wrinkled-and smooth- pea starch components. J. Carbohydrate Res. 126: 233-237.

Cornell H. J., and Hoveling A. W. 1998. Wheat: Chemistry and utilization. Switzerland: Technomic Publisher.

Cui S. W. 2005. Food Carbohydrates: chemistry physical properties and Applications, U.S: eRC press.

Das A. B., Singh G., Sing 5., and Riar C. S. 2010. Effect of acetylation and dual modification on physic-chemical, rheological and morphological characteristics of sweer potato (Ipomonea batatas) starch. Carbohydrate Polymers. 80(3): 725-732.

David J. T., and William A. A., 1999, Starches, U.S: American Association of Cereal Chemists.

De L. M. 1999, Biodegradable polystyrene foaming products. US patent 6,090,863

Deetae P., Shobsngob 5., Varanyanond W., Chinachoti P., Naivikul 0., and Varavinit S. 2008. Preparation, pasting properties and freeze-thaw stability of dual modified crosslink-phosphorylated rice starch. Carbohydrate Polymers 73 351-358

DOA (Department of agriculture Malaysia). Export Value of Agricultural Products 1998-2007. http://www.doa.sarawak.gov.my/statistik07 1 9 10.pdf. accessed on 12/09/09

84

Dokic L., Dapcevic T., Krstonosic V., Dokic P., and Hadnadev M. 2010. Rheological characterization fo corn starch isolated by alkali method. Food hydrocol/oids. 24(2): 172 - 177.

Dumitriu S. 2005. Polysaccharides: structural diversity and functional versatility, U.S: Marvel Dekker.

Eastman J.E., and Moore, e.O. 1984. Cold water soluble granular starch for gelled food compositions. U.S patent 4,465,702

Farahnaky A., Askari H., Majzoobi M., and Mesbahi Gh. 2010. The impact of concentration, temperature and pH on dynamic rheology of psyllium gels. Journal of food engineering. 4: 12 - 20

Fasihuddin. B., Ahmad. A., Peter W., Doublier. J., Durand 5., and Buleon A. 1999. Physico-chemical characterisation of sago starch. J. Carbohydrate Polymers, 38: 361-370.

FDA, 2007. Approximate pH of Foods and Food Products, http://vm.cfsanJda.gov/Ncommllacf-phs.html, retrieved on 12/09/09

FDA, 2009. Usting of food additive status. http://WWW . fda .gov IFood/FoodIngredientsPackagi ng/FoodAdditives/FoodAd ditiveUstings/ucm091048.htm. retrieved on 12/09/09

Felton G. E., and Schopmeyer H. H. 1943. Thick bodied starch and method of making. U.S. Patent 2,328,537.

Fennema O. R. 1996. Food Chemistry. 3rd edition. New York: Marcel Dekker Inc.

Rgura L. 0., and Teixeira A. A. 2007. Food Physics, Physical Properties -Measurement and Applications. New York: Springer Berlin Heidelberg.

Finocchiaro E. T., and Mass M. 1997. Fat free, reduced fat and low fat margarine­like spreads and cream cheese. US Patent 5,679,395

85

Flach M. 1997. Sago palm Metroxylon sagu Rottb. Promoting the conservation and use of underutilized and neglected crops. Rome, Italy: institute of Plant Genetics and Crop Plant Research, Gatersleben/ International Plant Genetic Resources Institute.

Graaf R. A., and Janssen L. P. B. M. 2003. The hydroxypropylation of starch in a self wiping twin screw extruder, Advances in polymer technology. 22(1): 56 -68

Gunaratne A., and Corke H. 2007. Influence of prior acid treatment on acetylation of wheat, potato and maize starches. Food chemistry. 15(3): 917 - 925.

Heath H. B. 1981. Source books offlavors, U.S: Van Nostrand Reinhold.

Horton D. 2004. Advances carbohydrate chemistry and biochemistry. U.S: Elsevier Ins.

Hui Y. H. 2006. Handbook of food science, technology and engineering, Volume 1, U.S: CRC Press.

Hung P. V., and Morita M. 2005. Physiochemical properties of hydroxypropylated and cross-linked starches from A-type and B-type wheat starch granules. Carbohydrate Polymers. 59(2): 239 - 246.

James N. B., and Whistler R. L. 2009. Starch: chemistry and technology, U.S: Elsevier Acedemic Press.

Jane J. L. and Seib P. A. 1991. Preparation of granular cold water swelling/soluble starches by alcoholic-alkali treatments. US patent 5,057,157.

Jane J., and Chen J. 1992. Effect of amylase molecular size and amylopectin branch chain length on paste properties of starch. Cereal Chem 69: 60 - 65.

Jane J., Graig S. A., Seib P. A., and Hoseney R. C. 1986. Characterization of Granular Cold Water Soluble starch. Starch/starke. 38: 258-263.

Jobling S. 2004. Improving starch for food and industrial applications, Current opinion in Plant biology. 7: 210 - 218.

86

Joythi A. N., Moorthy S. N., and Rajasekharan V. 2006. Effects of crosslinking with epichlorohydrin on the properties of cassava (Manihotesculenta Crantz) starch. Starch/Strake. 58: 292 - 299.

Kamal S. M., Mahmud S. N., Hussain S. A., and Ahmadun F. R. 2007. Improvement on sago flour processing. International Journal of Engineering and Technology. 4(1): 8 - 14.

Karim A. A., Nadiha M. Z., Chen F. K., Phuah Y. P., Chui Y. M., and Fazilah A. 2008. Pasting and retrogradation properties of alkali-treated sago (Metroxylon sagu) starch. Food Hydroco//oids. 22: 1044 - 1053.

Karim A. A., Tie P. A., Manan D. M. A., and Zaidul 1. S. M. 2008. Starch from the sago (metroxylon sagu) Palm tree - properties, prospects, and challenges as a new industrial source for food and other uses. Comprehensive reviews in food science and food safety. 7: 215 - 228

Kasapis 5., Sablani S. 5., and Biliaderis e. G. 2000. Dynamic oscillation measurements of starch networks at temperatures above 100°e. Carbohydrate Research. 329: 179 - 187

Kaur L., Singh N., and Singh J. 2004. Factors influencing the properties of hydroxypropylated potato starches. Carbohydrate Polymers. 55: 211 - 223.

Khondkar D., Tester R. F., Hudson N., Karkalas J., and Morrow J. 2007. Rheological behavior of uncross-linked and cross-linked gelatinized waxy maize starch with pectin gels. Food hydroco//oids. 21: 1296 - 1301.

Kim H. 5., and Huber K. C. 2010. Impact of NB-type granule ratio on reactivity, swelling, gelatinization, and pasting properties of modified wheat starch. Part I: Hydroxypropylation. Carbohydrate polymers. 80: 94 - 104.

Kim M. J., Choi S. J., Shin S. 1., Sohn M. R., Lee C. J., Kim Y., Cho W. 1., and Moon T. W. 2008. Resistant glutarate starch from adlay: Preparation and properties. Carbohydrate. 74: 787 - 796.

Kim M. 2003. Evaluation of degradability of hydroxypropylated potato starch/polyethylene blend films. carbohydrate Polymers. 54: 173 - 181.

87

Klingler R., and Busch K. G. 2006. Pregelatinized starches and processes for their production. U.S. Patent 7,045,003 B2.

Koo S. H., Lee K. Y., and Lee H. G. 2010. Effect of cross-linking on the physicochemical and physiological properties of corn starch. Food hydroco//oids. 24(6): 619 - 625.

Lawai O. S. 2004. Composition, physicochemical properties and retrogradation characteristics of native, oxidized, acetylated and acid thinned new cocoyam (Xanthosoma sagittifolium) starch. Food Chemistry. 87: 205 - 218.

Lawai O. 5., Adebowale K. 0., Ogunsanwo B. M., Barba L. L., and 110 N. S. 2005. Oxidized and acid thinned starch derivatives of hybrid maize: functional characteristics, wide angel X-ray diffractometry and thermal peroperties. International Journal of Biological Macromolecules. 35(1): 71 - 79.

Lawai O. 5., Ogundiran O. 0., Awokoya K., and Ogunkunle A. O. 2008. The low substituted propylene oxide etherified plantain (Musa paradissiaca norma lis) starch: Charaterization and functional parameters. Carbohydrate Polymers 74: 717 - 724.

Lee J. 5., Pang Y. C. and Bujang A. 2009. Alcoholic-alkaline treatment of dual­modified sago starch. Paper presented in llst ASEAN food Conference 2009, 21-23 October 2009. Bandar Seri Begawan. Brunei Darulsalam.

Lee J.S., Hoong K.Y., Bujang A., and Chin N.C. 2008. Optimization of GCWS Sago Starch Prepared by Alcoholic-Alkaline Treatment, Chemodynamics Res. 1(1) : 12-20.

Lenchin J. M., Trubiano P. c., and Hoffman S. 1985. Converted starches for use as a fat or oil replacement in foodstuffs. U.S. Patent 4,510,166.

Leusner S. J., Katcher J. H., and Joseph T. H. 1984. Process for hydroxypropylating starch. U.S. Patent 4,431,800.

88

Lii C. Y., Tsai M. L., and Tseng K. H. 1996. Effect of amylose content on the rheological property of rich starch. Cereal Chemistry. 73: 415 - 420.

Li J. Y., and Yeh A. 1. 2001. Relationships between thermal, rheological characteristics and swelling power for various starches. Journal of food engineering. 50: 141 - 148.

Lim 5., and Seib P. A. 1993. Preparation and pasting properties of wheat and waxy corn starch phosphates. Cereal Chemistry. 70: 137 - 144.

Liu H. 5., Yu L., Chen L., and Li L. 2007. Retrogradation of corn starch after thermal treatment at different temperatures. Carbohydrate Polymers. 69: 756 -762.

Liu H., Ramsden L., and Corke H. 1999. Physical properties and enzymatic digestibility of hydroxypropylated waxy and normal maize starch, Carbohydrate Polymers. 40: 175-182.

Manoi K., and Rizvi S. S. H. 2010. Physicochemical characteristics of phosphorylated cross-linked starch produced by reactive supercritical fluid extrusion. Carbohydrate Polymers. 81(3): 687 - 694.

McPherson A. E., and Jane J. 2000. Extrusion of cross-linked hydroxypropylated corn starches II. Morphological and Molecular Charaterization. Cereal Chem. 77: 326 - 332.

Mirmoghtadaie L., Kadivar M., and Shahedi M. 2009. Effects of croSS-linking and acetylation on oat starch properties. Food Chemistry. 116(3): 709 - 713.

Meng Y., and Rao M. A. 2005. Rheological and structural properties of cold-water­swelling and heated cross-linked waxy maize starch dispersions prepared in apple juice and water. Carbohydrate Polymers. 60: 291 - 300.

Mezger T. G. 2006. The rheology handbook: for users of rotational and OSCillatory rheometers. Germany: Vincentz Network.

Morikawa K., and Nishinari K. 2000. Rheological and DSC studies of gelatinization of chemically modified starch heated at various temperatures, Carbohydrate polymers. 43: 241- 247

89

Muhammad K., Hussin F., Man Y. C., Ghazali H. M., and Kennedy J. F. 2000. Effect of pH on physphorylation of sago starch. Carbohydrate Polymers. 42: 85 -90.

Nadiha M. Z. N., Fazilah A., Bhat R., and Karim A. A. 2010. Comparative susceptibilities of sago, potato and corm starches to alkali treatment. Food chemistry. 121: 1053 - 1059.

Nishimura Y., and Laufa T. M. 2002. A comparative study on technology adaptation for sago starch extraction in pacific and Asian Local regions. Sago Palm. 10: 7 -15

O'Rourke J. D. 1980. Starch for instant pudding. U.S. Patent 4,215,152.

Olmsted J. and Williams G. M. 1997. Chemistry, the molecular science. (2nd edition), U.S: Wm. C. Brown.

Onofre F. 0., and Wang Y. J. 2010. Hydroxupropylated starches of varying amylose contents as sustained release matrices in tablets. International Journal of pharmaceutics. 385(1): 104 - 112.

Ornanong S. K., Burapadaja 5., and Nisit K. 2008. Development of pharmaceutical Gel base containing Sodium carboxymethyl Mungbean starch. CMU j Nat Sci. 71(1): 23

Pal, J., Singhal, R. 5., and Kulkarni, P. R. 2002. PhYSicochemical properties of hydroxypropyl derivative from corn and amaranth starch. Carbohydrate polymers. 48: 49-53.

Pang Y. C. 2009. Kesan dwi modifikasi dan rawatan alcohol-alkali ke atas cirri-ciri kanji sagu, Sekolah Sains Makanan dan Pemakanan, Universiti Malaysia Sabah

Perera c., Hoover R., and Martin A. M. 1997. The effect of hydroxypropylation on the structure and physicochemical properties of native, defatted and heat­moisture treated potato starches. Food Research International. 30(314): 235-247

90

Perez L. A. B., Ramos S. M. c., Manilla R. R., Feria J. 5., and Aparicio A. J. 2002. Chemical and functional properties of modified starch from Banana Musa paradisiacal L. (VAR. MACHO). ARTiCULO en Agrociencia. 36: 169-180

Pitchon E., O'Rourke D., and Joseph T. H. 1981. Process for cooking or gelatinize materials, U.S. Patent 4,280,851.

Pompilia 1. 5., Francois R., Iman H., Michel P., and Mircea A. M. 1999. Structure­properties relationship in cross-linked high amylose starch for use in controlled drug release. Carbohydrate research. 323(1): 163 - 175.

Protserov V. A., Wasserman L. A., Tester R. F., Debon S. J. J., Ezernitskaja M. G., and Yuryev V. P. 2002. Thermodynamic and structural properties of starches extracted from potatoes grown at different environmental temperatures. Carbohydrate Polymers. 49: 271 - 279

Rajagopalan 5., and Seib P. A. 1991. Process for the preparation of granular cold water soluble starch. U.S. Patent 5,037,929.

Rajagopalan 5., and Seib P. A. 1992. Granular cold water soluble starches prepared at atmospheric pressure. Joumal of Cereal Science. 16: 13 - 28.

Ratnayake W. 5., and Jackson D. S. 2008. Phase trasition of cross-linked and hydroxypropylated corn (Zea mays L.) starches. LWT - Food science and technology. 41(2): 346 - 358.

Redhead J. 1989. Utilization of tropical foods: trees, FAO. Food and nutrition paper 47(3): 3 - 5.

Riel R. R. 1960. SpeCification for the spreadability of butter. Ottawa, Canada: Dairy Technology Research Institute.

Robyt J. F., Choe J. Y., Hahn R. 5., and Fuchs E. B. 1996. Acid modification of starch granules in alcohols: effects of temperature, acid concentration and starch concentration. Carbohydrate Research. 281: 203 - 218.

Roger. P., and Colonna. P. 1993. Evidence of the presence of large aggregates contaminating amylose solutions. Carbohydrate Polymer. 21: 83-89.

91

Saartrat 5., Puttanlek C., Rungsardthong V., and Uttapap D. 2005. Paste and gel properties of low substituted acetylated canna starches. Carbohydrate polymers. 61: 211-221.

sae-kang V., and suphantharika M. 2006. Influence of pH and xanthan gum addition on freeze-thaw stability of tapioca starch pastes. Carbohydrate Polymers. 65: 371-380.

Sajilata M. G., and Singhal R. S. 2003. Specialty starches for snack foods. carbohydrate polymers. 59(2): 131 - 151.

Sang Y., and seib P. A. 2006. Resistant starches from amylose mutants of corn by simultaneous heat-moisture treatment and phosphorylation. Carbohydrate polymers. 63: 167-175.

Satin M. 2000. Functional properties of starches, FAD agriculture and food engineering technologies services. http://www.fao.org/ag/ags/agsi/starch41.htm. retrived on: 22/09/09

Shi X., and BeMiller N. 2002. Effect of food gums on viscosities of starch suspensions during pasting. carbohydrate Polymers. 50: 7 - 18.

Singh J. and Singh N. 2003. Studies on the morphological and rhelogical properties of granular cold water soluble corn and potato starches. Food hydrocol/oids. 17: 63 -72.

Singh J., Kaurb L., and McCarthy OJ. 2007. Factors influencing the physico­chemical, morphological, thermal and rheological properties of some chemically modified starches for food applications-A review. Food Hydrocolloids. 21: 1-22.

Singhal R. 5., Kennedy J. F., Gopalakrishnan S. M., Kaczmarek A., Knill C. J., and Akmar P. F. 2008. Industrial prodUction, processing and ultilization of sago palm-derived products. carbohydrate Polymers. 72: 1 - 20

Sodhi N. 5., Chang Y. H., Kaur N., and Kohyama K. 2009. Effect of acid-methanol treatment on the molecular structure and physicochemical properties of lentil (Lens culinaris MediK) starch. Food hydrocol/oids. 23(8): 2219 - 2225.

92

Stephen A. M., Philips G. 0., and Williams P. A. 2006. Food polysaccharides and their applications, (2nd edition). USA: CRC Press.

Swenson B. J., Wendorff W. L., and Undsay R. C. 2000. Effects of ingredients on the functionality of fat-free process cheese spreads. Journal of food science. 65(5): 822 - 826.

Teoh H. B. 2009. Kesan hidrosipropilasi dan rawatan alcohol-alkali ke atas cirri-ciri kanji sagu. Sekolah Sains Makanan dan Pemakanan, Universiti Malaysia Sabah.

Tessler M. M. 1975. Hydroxypropylated, inhibited high amylose retort starches. U.S. Patent. 3,904,601

Tester R. T., and Morrison W. R. 1990. Swelling and gelatinization of cereal starches. Effect of amylopectin, amylose and lipids. Cereal Chemistry. 67(6): 551- 557.

Tester R. F., Karkalas J., and Qi X. 2004. Starch - composition, fine structure and architecture. Journal of Cereal Science. 39: 151 - 165.

Ticher P. C. S. F., Noseda M. D., Freitas R. A., Sierakowski M. R., and Duarte M. E. 2006. Effects of iota-carrageenan on the rheological properties of starches, Carbohydrate Polymers. 65: 45 - 57

Tomoko H., Tamao, H., Shoon, J. F., Keiji, K., and Setsuko T. 2000. Physicochemical properties of starches obtained from various parts of sago palm trunks at different growth stages (Part 2). The relative crystallinity, structure, and gelatinization properties of sago starches at different growth stages. Journal of Applied Glycoscience. 47: 335-341.

Trksak R. M., and Ford P. J. 2008. Sago-based gelling starches. U.S. Patent 7,422,638.

Uriyapongson J., and Rayas D. P. 2000. Effect of modified potato starch and white wheat class on alkaline noodle properties. AACC 2000 annual meeting.

93

Vaclavik V. A., and Christian E. W. 2008. Essentials of food science. New York: Springer Science,

Wang S. J., Gao W. Y., Yu J. L., and Xiao P. G. 2006. The crystalline changes of starch from Rhizoma Diosorea by acid hydrolysis. Chinese Chemical Letters. 17(9): 1255 - 1258.

Wang Y. J., Truong V. D., and Wang L. 2002. Structures and rheological properties of corn starch as affected by acid hydrolysis. carbohydrate polymers. 52: 327 - 333.

Warner K., and Eskin N. A. M. 1995. Methods to assess quality and stability of oils and fat-containing foods. U.S: AOCS Press.

Wattanachant 5., Muhammad K., Hashim D. M., and Rahman R. A. 2003. Effect of crosslinking reagents and hydroxypropylation levels on dual-modified sago starch properties. Food Chemistry. 80: 463-471

Wattanachant 5., Muhammad S. K. 5., Hashim D. M., and Rahman R. A. 2002a. Suitability of sago starch as a base for dual-modification. Songklanakarin J. Sci. Technol. 24(3): 431-438

Wattanachant, 5., Muhammad, S. K. 5., Mat Hashim, D. and Rahman, R. A. 2002b.

Wolf,

Characterisation of hydroxypropylated crosslinked sago starch as compared to commercial modified starches. Songklanakarin J. Sci. Techno!. 24(3): 439-450

W. B., Bauer, L. L., and Fahey, G. c., Jr. 1999. Effects of chemical modification in vitro rate and extent of food starch digestion: An attempt to discover a slowly digested starch. Journal of Food and Agricultural Chemistry. 47: 4178-4183.

Woo K., Bassi S. D., Maningat C. c., Zhao L., Trompeter E. E., Kelley G. A., Ranjan 5., Gaul J., Dohl C. T., DeMeritt G. K., Stempien G. J., and Krehbiel K. D. 2006. Pregelatinized chemically modified resistant starch products and uses thereof. U.S patent 2006/0188631.

Wu Y. 5., and Seib P. 1990. Acetylated and Hydroxypropylated Distarch Phosphate from Waxy Barley: Paste Properties and Freeze-Thaw stability Cereal Chem. 67(2): 202 - 208.

94

Wursch P., and Tolstoguzov V. B. 1997. Low fat spreadable food product. International patent W097/25875.

Wurzburg O. B., and Stephen A. M. 2006. Food polysaccharides and their application. New York: Marcel Dekker.

Xie X., Uu Q., and Vui S. W. 2006. Studies on the granular structure of resistant starches from normal, high amylase and waxy corn starch citrates. Food Research International. 39: 332 - 341.

Yan H., and Zhengbiao G. U. 2010. Morphology of modified starches prepared by different methods. Food research international. 43: 767 - 772.

Yap L. K. 2009. Kesan silang paut dan rawatan alcohol-alkali ke atas cirri-ciri kanji sagu. Sekolah Sains Makanan dan Pemakanan. Universiti Malaysia Sabah.

Yeh A., and Yeh S. L. 1993. Some Characteristics of Hydroxypropylated and Cross­linked Rice Starch. Cereal Chem. 70(5): 596 - 601.

Yiu P. H., Loh S. L., Rajan A., Wong S. c., and Bong C. F. J. 2008. Physiochemical properties of sago modified by acid treatment in alcohol. American Journal of applied sciences. 5(4): 307 - 311.

Yoneya T., Ishibashi K., Hironaka K., and Yamamoto K. 2003. Influence of cross­linked potato starch treated with POCh on DSC, rheological properties and granule size. Carbohydrate Polymers 53: 447 - 457.

You S. and Izydorczyk M. S. 2007. Comparison of the physicochemical properties of barley starches after partial a-amylolysis and acid/alcohol hydrolysis. Carbohydrate polymers. 69(3): 489 - 502.

Yuryev V., Tomasik P., and Betoft E. 2007. Achievements in understanding of structure and functionality. New York: Nova Science Publishers Inc.

Zhao H, Kwak J. H., Zhang Z. c., Brown H. M., Arey B. W., and Holladay J. E. 2006. Studying cellulose fiber structure by SEM, XRD, NMR and acid hydrolYSiS. Carbohydrate polymers. 68(2): 235 - 241.

9S

Zhao J. J., and Dale T. B. 2007. Instantly dispersible pregelatinized starches for use in food products. U.S patent 7,288,277.

Zheng G. H., Han H. L., and Bhatty R. S. 1999. functional properties of cross-linked and hydroxypropylated Waxy hull-less Barley starches. Cereal Chem. 76(2) : 182 - 188

96