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ENZYME RESISTANT STARCH TYPE III PRODUCTION FROM HIGH AMYLOSE RICE STARCH AND APPLICATION IN LOW GLYCEMIC INDEX BUTTER CAKE INTRODUCTION Rice (Oryza sativa L.) is a major cereal of Thailand. Commercial rice starch composed of up to 90 % carbohydrates and 0.5-1.5 % protein with negligible fat or dietary fiber (Juliano, 1992). Rice flour and starch become popular food ingredients since they are hypoallergenic, low fat and neutral in flavor. However, rice starch is high glycemic index (GI) food, which was low in resistant starch (RS) content. Freshly cooked rice contains below 3% of RS content, but the RS tends to increase with amylose content and processing treatments (Walter et al. 2005). RS has been recently defined as the sum of starch and its degradation products that are not absorbed in the small intestine of healthy individuals (Englyst et al. 1999). The reduced bioavailability of RS in the human gastrointestinal tract has particular significance for diabetics because it lowers the insulin response. Besides physiological benefits in human, RS has been reported to have potential use as a unique ingredient with improved oral tactile perception, taste palatability, color and texture. RS can be found in nature and its contents of RS are varied by botanical source and starch granular structure (resistant starch type I and II). In addition, resistant starch can be produced from retrogradation of gelatinized starch known as resistant starch type III (RS III). There has been previously published study to produce appropriate technology for RS III formation from high amylose rice starch and its stability in food applications. Thus, the primary purpose of this study was to improve RS III from high amylose rice starch by enzymatically-debranching process. The extents of RS III of most starches are, however, are quite low, depending on the molecular structure of starch glucans, namely amylose and amylopectin. High amylose starch produced higher resistant starch than low amylose starch. Debranching using pullulanase have 1
een used to produce a sample with linear, low-molecular-weight and recrystallization polymer chains (Guraya et al. 2001 and Yin et al. 2007). Debranching enzymes rapidly hydrolyze only α-1,6-glucosidic bonds. This releases a mixture of varied unit chain length from the amylopectin molecule which in turn facilitated starch retrogradation. In addition, retrogradation is often enhanced when starch gels are subjected to freezing and thawing treatments (Tovar et al. 2002). Freezing a starch gel leads to the formation of ice crystals and thus concentrates the starch in non-ice phase. Upon thawing, the water can be easily compressed from the network, giving rise to a phenomenon known as syneresis (Tovar et al. 2002). The recrystallinity of rice starch was altered by pullulanase debranching and freeze-thaw process. The effects of these treatments on degree of hydrolysis, degree of syneresis, degree of crystallinity, physicochemical properties, in vitro starch digestibility and glycemic index were examined. The optimum condition of RS formation was selected to application in low glycemic index butter cake product. The food industry is being challenged to redesign traditional foods for optimal nutritional value, in response to some population sectors with particular nutritional necessities and making them as tasty as or better than the original. One way to achieve a healthy food product is to reduce or to omit some of the glucoseladen ingredients, especially flour and sugar since, at present, diabetic and obesity is frequently cited as a serious health problem. At the same time, there is a constant demand for dietetic foods suitable for diabetics, which may have the same calorievalue being also sucrose-free since this sugar cannot be metabolized without insulin. For this reason, it is a challenge to develop food products, which was a cake in this study that low glycemic index for individuals who are intolerant to glucose by using RS III as flour replacement and high fructose corn syrup as sucrose replacement. Many carbohydrate-rich foods have high glycemic indexes (GI.), and certainly are not good in any substantial quantity for people with diabetes. RS III is broken down and degrade more slowly, releasing glucose gradually into our blood streams and are said to have lower glycemic indexes. Fructose is very sweet, is roughly 1.75 times sweeter than sucrose, and is defined as low glycemic ingredient (Jenkin et al. 2002a). Because fructose must be changed to glucose in the liver in order to be utilized by the body, 2
Page 1: THESIS ENZYME-RESISTANT STARCH TYPE
Page 5 and 6: ACKNOWLEDGEMENTS I wish to express
Page 7 and 8: LIST OF TABLES Table Page 1 Classif
Page 9 and 10: LIST OF TABLES (Continued) Table Pa
Page 11 and 12: LIST OF FIGURES (Continued) Figure
Page 13 and 14: LIST OF FIGURES (Continued) Appendi
Page 15: LIST OF ABBREVIATIONS (Continued) R
Page 19 and 20: Overall objectives: OBJECTIVES 1. T
Page 21 and 22: However, it was discovered that a r
Page 23 and 24: Cassidy et al. (1994), in an intern
Page 25 and 26: fed both the 45 and 63g/100g rice s
Page 27 and 28: only about 3 g. The physiological b
Page 29 and 30: (Brown et al. 1995). This product,
Page 31 and 32: Figure 1 A detailed structure of th
Page 33 and 34: 2.3 Chemical composition of rice st
Page 35 and 36: helix with only the ring oxygen poi
Page 37 and 38: Figure 5 Idealized diagram of the c
Page 39 and 40: 2.5 Rice starch gelatinization Gela
Page 41 and 42: in excess water. The loss of birefr
Page 43 and 44: morphological changes occurring at
Page 45 and 46: amylose is the linear fraction of s
Page 47 and 48: units are known to inhibit retrogra
Page 49 and 50: (-1 to 43 o C) on concentrated star
Page 51 and 52: Figure 10 Schematic diagram showing
Page 53 and 54: ice due to the various cooking and
Page 55 and 56: Recently, there has been a flurry o
Page 57 and 58: 3.1 Processing condition on improve
Page 59 and 60: of RS overall, 60%, among the three
Page 61 and 62: chains but liberates longer chains
Page 63 and 64: 4.1 Amylolytic enzymes Three groups
Page 65 and 66: Structure and properties of β- amy
Page 67 and 68:
Structure and properties: The pullu
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Action pattern: The amyloglucosidas
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methods, for instance in scanning e
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6. Low glycemic butter cake product
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Sugar increases cake volume by decr
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cereals, and baked potatoes. Low gl
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way to achieve a healthy food produ
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complexes. In the meantime, and inv
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would be only 2. In comparison, the
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ecause of an absolute decrease in t
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enhanced fat oxidation at the expen
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1. Raw Materials MATERIALS AND METH
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Methods 1. Production of resistant
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1.2.3 Degree of syneresis Degree of
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1.2.9 Starch hydrolysis rate and es
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1.3.3 Resistant starch content, sta
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2.1.1 Cake sample preparation Cake
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Nevertheless, the former refers to
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3. Experimental Design and Statisti
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essentially linear polymer of α-(1
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hydrolysis of the rice starch prehe
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a) b) Figure 15 Scanning electron m
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amylose content of starch had a har
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Degree of syneresis (%) 70.0 60.0 5
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1.2.7 Physicochemical properties of
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1.2.8 In vitro starch digestibility
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1.2.9 Hydrolysis index and glycemic
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Table 16 Effect of preheated treatm
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1.2.10 Crystallinity of RS III 108
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Figure 22 X-ray diffraction pattern
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content. The high correlation facto
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1.3.2 β-amylolysis (%) 114 β-amyl
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1.3.4 In vitro starch digestibility
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118 Non significant differences (P
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1.4.2 Degree of hydrolysis 120 The
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2 An application of resistant starc
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sucrose or maltose are reducing suc
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126 The different effect of HFCS on
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2.1.2 Sensory evaluation of HFCS re
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and objective percent moisture gene
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132 In the dietetic cake mix of Cor
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3) In vitro starch digestibility 13
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Table 23 Percentage (dwb) of starch
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al. (2006) reported that when gluco
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140 volume, crust and crumb color o
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(P
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2.2.2 Sensory evaluation of RS III
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3) Flavor score 146 Flavor is the m
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2.2.3 Chemical composition of RS II
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Table 27 Mean values for chemical c
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Table 28 Percentage (dwb) of starch
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cake is lower in these samples than
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CONCLUSIONS AND RECOMMENDATIONS 156
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158 syneresis of retrograded starch
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LITERATURE CITED Abe, J.I., K. Naka
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Biliaderis, C.G. and J. Zawastowski
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Cheng, H.H. and M.H. Lai. 2000. Fer
Page 181 and 182:
Elgun, A. Z. Ertugay, M. Certel, an
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Fitt L.E. and E.M. Snyder. 1984. Ph
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Grandfeldt, A., C. Eliasson and I.
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Hoseney, R.C. 1990. Principles of C
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Juliano, B.O. and M.S. Goddard. 198
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Lavin, M., E. Eshbaugh, J.-M. Hu, S
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Ludwig, D.S. and R.H. Eckel. 2002.
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Meilgaard, M., Civille, O.V., and C
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Nakazawa, F., S. Noguchi, J.Takahas
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Piyarat, N. 2003. The assessment of
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Schoch, T. J. 1969. Non-carbohydrat
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Srinivasa Rao, P. 1970. Studies on
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Towar, J., C. Melito, E. Herrera, A
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Yuan, R.C. and D.B. Thompson. 1998.
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Appendix A Chemical analysis proced
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2.2 Method determination 196 Total
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source and detach the extractor and
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5.3 Procedure for Preparation for S
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1) Standard curve procedure 202 Usi
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7. Reducing sugar determination by
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8. Resistant starch determination b
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8.2.3 Measurement of resistant star
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lank. starch. 210 3. Measure the ab
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Appendix B Physical analysis proced
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2. X Ray Diffraction Measurement 2.
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Appendix C Picture of some experime
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Heated debranched samples Cooled de
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Appendix Figure C4 Visuals appearan
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1. Introduction 222 There are sever
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Appendix E Experimental data 224
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Appendix Table E3 X-ray diffraction
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Appendix F List of publications 228
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NAME : Miss Jirapa Pongjanta BIRTH
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