(Luận văn tốt nghiệp) effects of temperature and reaction time of liquid hot water pretreatment for sugar production from cassava pulp

THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY TO HONG ANH THESIS TITLE: EFFECTS OF TEMPERATURE AND REACTION TIME OF LIQUID HOT WATER PRETREATMENT FOR SUGAR PRODUCTION FROM CASSAVA PULP BACHELOR THESIS Study Mode : Full - time Major : Food Technology Faculty : Biotechnology and Food Technology Batch : 2014 – 2018 Thai Nguyen, 2018 Luan van THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY TO HONG ANH THESIS TITLE: EFFECTS OF TEMPERATURE AND REACTION TIME OF LIQUID HOT WATER PRETREATMENT FOR SUGAR PRODUCTION FROM CASSAVA PULP BACHELOR THESIS Study Mode : Full - time Major : Food Technology Faculty : Biotechnology and Food Technology Batch : 2014 – 2018 Supervisors : Assoc Prof Dr Pawinee Chaiprasert Mr Suppanut Varongchayakul Msc Trinh Thi Chung Thai Nguyen, 2018 i Luan van DOCUMENTATION PAGE WITH ABSTRACT Thai Nguyen University of Agriculture and Forestry Major Food Technology Student name To Hong Anh Student ID DTN 1453170065 Effects of temperature and reaction time of liquid Thesis Title hot water pretreatment for sugar production from cassava pulp Assoc Prof Dr Pawinee Chaiprasert Supervisors Mr Suppanut Varongchayakul Msc Trinh Thi Chung Abstract: Cassava is one of the important food crops in the world Most of cassava was cultivated in the tropical or subtropical area [1] Thailand was the major country that cultivated cassava Cassava root was rich in starch which was mostly used as raw material in cassava starch production Cassava pulp was the waste residue by product from cassava starch manufacture [2] Cassava pulp contains about 50–70% starch and 20–30% of lignocellulose (LCMs) on a dry weight basis [3] However, the direct hydrolysis of cassava pulp had low efficiency due to the recalcitrant properties of LCM and starch was trapped in cell wall of LCMs [4] To fully utilize, pretreatment step was applied before hydrolysis step which impact on cell wall properties of cassava pulp to improve the hydrolysis efficiency next step [5] Pretreatment used physical, chemical, physico-chemical or biological agent [6] Liquid hot water (LHW) pretreatment used the combination of physical and chemical process The pressure in this method was used to keep water in the liquid state under high temperature [7] During LHW, water is penetrated into the cell wall structure and caused the hydrating of starch and cellulose, solubilization of hemicellulose and partial remove lignin of the structure These effects caused increasing the surface area which lead to improve the efficiency in hydrolysis step ii Luan van and enhance the sugar recovery [8] Moreover, the effectiveness of LHW depends on many factors such as time reaction, temperature, pressure and solid:liquid ratio [9] In this work, the effective of process variables (temperature and reaction time) in LHW pretreatment of cassava pulp for sugar production was addressed by means of design of experiments The result show that condition at 180°C for 15 minutes, obtained the highest amount of total sugar at 703 mg/g CP Keywords: Cassava pulp, liquid hot water pretreatment, temperature reaction time, sugar production Number of pages: 23 Date of Submission: 08/06/2018 iii Luan van ACKNOWLEDGMENTS To complete this bachelor thesis, in addition to my own efforts, I have received great encouragement and supports from many individuals and groups during the internship since December 18th, 2017 to May 25th, 2018 Firstly, I would like to express my gratitude to my supervisors Assoc Prof Dr Pawinee Chaiprasert and my mentor Mr Suppanut Varongchayakul from School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi (KMUTT), Bangkok, Thailand and Msc Trinh Thi Chung from Department of Food Technology, Faculty of Biotechnology and Food Technology, Thai Nguyen University of Agriculture and Forestry (TUAF), Thai Nguyen City, Vietnam, who help and give me the best conditions to complete the bachelor thesis A special thanks to the Phytobioactive and Eco-Waste Lab members for motivating and teaching me about lab research works Moreover, I would like to thanks my family, my friends for supporting me as an internship at KMUTT I sincerely appreciate all supports from lecturers at Faculty of Biotechnology and Food Technology, TUAF, I also thank the Vietnamese students and my friends in Thailand for helping me during this internship iv Luan van TABLE OF CONTENTS PAGE DOCUMENTATION PAGE WITH ABSTRACT i ACKNOWLEDGMENTS .iv TABLE OF CONTENTS v LIST OF FIGURES .vi LIST OF TABLES vii LIST OF ABBREVIATIONS viii PART I INTRODUCTION 1.1 Rationale 1.2 Problem statement and justification 1.3 Objectives 1.4 Hypothesis 1.5 Expect benefits PART II METHODOLOGY 2.1 Materials 2.2 Methods 2.2.1 Sample preparation 2.2.2 Analytical methods 2.2.3 Liquid hot water (LHW) pretreatment 14 PART III RESULTS AND DISCUSSION 16 3.1 Characterization of substrate 16 3.2 Effect of temperature and reaction time on solid remaining 17 3.3 Effect of temperature and reaction time on total sugar and reducing sugar of cassava pulp 18 3.3.1 Reducing sugar .20 3.3.2 Total sugar 21 PART IV CONCLUSION AND RECOMMENDATION 23 5.1 Conclusion .23 5.2 Recommendation .23 REFERENCES 24 APPENDICES A 30 v Luan van LIST OF FIGURES Fig 1.1 Top 10 country production of cassava in the world (FAO, 2016) Fig 1.2 Lignocellulose materials structure .2 Fig 2.1 Cassava pulp after dry Fig 3.2 The result of characterization of cassava pulp in % dry weigh basis .16 Fig 3.2 The content of reducing sugar in hydrolysate after LHW pretreatment 20 Fig 3.3 The content of total sugar in hydrolysate after LHW pretreatment .21 vi Luan van LIST OF TABLES Table 2.2 Following the LHW pretreatment .15 Table 3.1 Chemical composition of cassava pulp in % dry 16 Table 3.2 Results of substrate after LHW pretreatment .18 Table 3.3 Results of reducing sugar and total sugar 18 Table A1 The temperature and reaction time value of LHW were range of 140°C 180°C and - 30 for total sugar and reducing sugar 30 Table A2 Effect of liquid hot water pretreatment at 140oC with various reaction time conditions for total sugar and reducing sugar 31 Table A3 Effect of liquid hot water pretreatment at 160oC with various reaction time conditions for total sugar and reducing sugar 32 Table A4 Effect of liquid hot water pretreatment at 180oC with various reaction time conditions for total sugar and reducing sugar 33 vii Luan van LIST OF ABBREVIATIONS µg Microgram µL Microlitre ADF Acid detergent fiber ADL Acid detergent lignin Conc Concentration CP Cassava pulp Fig Figure g Gram hr Hour L Litre LCMs Lignocellulose material LHW Liquid hot water mg Milligram Minute mL Millilitre mm Milli mol NDF Neutral detergent fiber nm Nano mettre rpm Revolutions per minute RS Reducing sugar sec Seconds TS Total sugar viii Luan van PART I INTRODUCTION 1.1 Rationale Cassava is the third-largest source of food carbohydrates in the world [10] Cassava is a major staple food in the developing world, providing a basic diet for over half a billion people [11] It is mainly use for processing chips, pellets and starch- by processing The following statistics of FAOSTAT (2013) reported that Thailand was mainly used for food, feed, and fuel Thailand is the first world exporter of cassava chips and cassava starch, as well as the second largest producer after Nigeria in cassava production in 2016 [12] According the data showed in the chart below 70 Production (Mtonnes) 57.14 50 31.16 30 21.1 20.75 17.8 10 14.7 11.06 10.21 9.98 9.1 -10 Country Fig 1.1 Top 10 country production of cassava in the world (FAO, 2016) Cassava roots are very rich in starch that was used main material of cassava starch industry When dried to a powdery (or pearly) extract, is called cassava starch (Tapioca) During cassava starch processing, the range of using cassava roots to production ton of cassava starch were about 3.5- 4.8 tons For agriculture residues from cassava starch production included cassava peel was 50- 160 kg and cassava pulp was 1.0- 2.8 tons [12] By this conclusion, the mount of cassava pulp from cassava starch processing have a huge solid residue - by product This is available and cheap material but the utilization of cassava pulp did not have high efficiency Normally cassava pulp was sale for animal feed at low price Therefore the enhancement of Luan van derive into sugar recovery Due to, the sugar degradation at high temperature and turning these components into lower molecular weight products, such as furfural, hydroxyl methyl furfural, inhibitors [55] 3.3.1 Reducing sugar Under all the conditions assayed, a certain amount of glucose was found in hydrolysate (see Fig 3.2.1) The fact that glucose is found in hydrolysate even at control conditions (without pretreatment) suggests that it derives from other source than LCMs The presence of some grain starch in the cassava pulp sample could be the origin of this easily- solubilized glucose [56] However, this reducing sugar had low with 5.8mgRS/gCP at control condition and 12mgRS/gCP at autoclave condition This chart below showed amount of reducing sugar at different LHW conditions mg RS/gCP 400 140 °C 302.9 300 160 °C 260.4 180 °C 200 130.5 100 58.5 55.8 23.9 41.91 9.9 29 15 30 minutes Fig 3.2 The content of reducing sugar in hydrolysate after LHW pretreatment The analysis reducing sugar of hydrolysate obtained after pretreatment showed that an increase of reaction time from to 30 minutes at 140°C resulted in reducing sugar yield rising from mg up to 41.9 mg (Fig 3.2.1) By increasing the temperature to 160°C that same time, the content of reducing sugar increased to triple of this value, 20 Luan van from 23.9 mg (140°C for 30 min) up to 130.5 mg (160°C for 30 min) Continue to increase the temperature to 180°C for reaction time from to 30 minutes, the result in reducing sugar rising from 55.8 mg to 302.9 mg respectively In all conditions at 180°C , The condition at 15 minutes have content of reducing sugar higher than at time condition times While increased of time from 15 to 30 min, the content of reducing sugar rising negligible from 260 mg up to 302.9 mg This results show that temperature and time of LHW not have linear relationship [55] 3.3.2 Total sugar The analysis total sugar (TS) at all conditions assayed, amount of total sugar at control condition was about 37.2 mg and 211.7 mg at autoclave condition , and other results of hydrolysate obtained after pretreatment under the conditions of experiment were show in Fig 3.3 below mg TS/g CP 800 762 140 °C 160 °C 635 600 180 °C 552 550 452 400 290 279 268 229 200 0 15 30 minutes Fig 3.3 The content of total sugar in hydrolysate after LHW pretreatment Under all the conditions assayed, the content of total sugar of hydrolysate after LHW increased progressively with temperature and reaction time from to 30 minutes at 140°C to 180°C ( see Fig 3.2.2) It can be see that at 140°C increased in total sugar 21 Luan van recovery yield was observed at extended reaction time varying from 229 mg at 15 to 552 mg at 30 Likewise, at condition of 160°C , the increasing in total sugar recovery occurred when the reaction time increasing However, at 180°C the increasing over 15 minutes led to total sugar value shifting from 762 mg at 15 to 452 mg at 30 All of the conditions, a maximum total sugar recovery value 762 mg of content was reached at 180°C for 15 minutes When the reaction time increased 30 minutes that the sugar loss over 302 mg in the same temperature condition The decrease of total sugar in hydrolysate occurs, which indicate that the degradation reaction sugar enhanced into lower molecular and the generations of inhibitors occurred, under harsh condition at high temperature for extended residence time [57] This result is similar to some reports, during pretreatment the sugar can be degrade at high temperatures turning these components into lower molecular weight products, such as furfural, hydroxyl methyl furfural, acid acetic or inhibitors [20, 58] 22 Luan van PART IV CONCLUSION AND RECOMMENDATION 5.1 Conclusion Through our research at the Phytobioactive and Eco- Waste Laboratory, Bangkok, Thailand, we make the following conclusions: The content of sugar recovery in hydrolysate after LHW pretreatment were higher than control condition and autoclave condition (without pretreatment) suggest that during LHW, the partical of LCMs and starch of cassava pulp were hydrolysis into sugar [59] Moreover, the sugar content were different depend on temperature and reaction time conditions under saturated vapor pressure[60] Moreover, Increasing of temperature and reaction time was not always increasing of sugar content Higher solubilization was obtained under harsher conditions only up to certain of temperature and reaction time The most favorable condition would be that corresponding to the sugar yield where 760 mg total sugar and 260 mg of reducing sugar at 180°C for 15 5.2 Recommendation Although, the sugar recovery in hydrolysate (after LHW) was high, but the large amount of water was used during LHW pretreatment, causing low sugar concentration difficult for collection From the results obtained in this work, it can be inferred that to attain a maximum sugar production from cassava pulp, it would be necessary to carry out the process in two stages A first pretreatment stage, aimed at maximizing hydrolysate recovery, and a second stage, aimed at ensuring the maximum glucose recovery The combination of LHW pretreatment and hydrolysis (or fermentation) next step on cassava pulp that the potential methods used for better sugar production [61] The process of hydrolysis was the necessary step to convert polysaccharides into monomers The pretreatment step was occurred to enhance and improve the sugar yield in hydrolysis step In this study was applied pretreatment step only So, it is recommended that takes more time to hydrolysis or fermentation next step From there, it can be to enhance the efficiency in 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"Liquid hot water pretreatment of lignocellulosic biomass for bioethanol production accompanying with high valuable products", Bioresource technology, 19968-75 59 Behera, S., et al.,(2014), "Importance of chemical pretreatment for bioconversion of lignocellulosic biomass", Renewable and Sustainable Energy Reviews, 3691-106 60 Sarkar, N., et al.,(2012), "Bioethanol production from agricultural wastes: an overview", Renewable energy, 37(1),19-27 61 Yang, B and C.E Wyman,(2004), "Effect of xylan and lignin removal by batch and flowthrough pretreatment on the enzymatic digestibility of corn stover cellulose", Biotechnology and bioengineering, 86(1),88-98 62 Putro, J.N., et al.,(2016), "Pretreatment and conversion of lignocellulose biomass into valuable chemicals", RSC Advances, 6(52),46834-46852 29 Luan van APPENDICES A Table A1 The temperature and reaction time value of LHW were delimited within a range of 140°C - 180°C and - 30 for total sugar and reducing sugar Pretreatment conditions Sugar production Reducing sugar Total sugar 5.8i 37.2k Autoclave 121°C,15 12.0h 211.7j LHW 140°C,0min 9.9hi 228.9i LHW 140°C,15min 29.0f 258.9h LHW 140°C,30min 34.4f 552.2c LHW 160°C,0min 23.9g 290.4f LHW 160°C,15min 61.9d 490.8d LHW 160°C,30min 130.5c 635.2b LHW 180°C,0min 55.8e 279.4g LHW 180°C,15min 260.4b 762.2a LHW 180°C,30min 302.9a 452.6e F-test *** *** C.V (%) 0.76 3.61 Control 25°C,30min All values are expressed as dried basis (mean ± SD) Mean data three replicates Different data in the same column mean significant difference (p ≤ 0.05) 30 Luan van Table A2 Effect of liquid hot water pretreatment at 140oC with various reaction time conditions for total sugar and reducing sugar Sugar production Pretreatment conditions Reducing sugar Total sugar 5.8e 37.2e Autoclave 121°C,15 12.0d 211.7c LHW 140°C,0min 9.9c 228.9d LHW 140°C,15min 29.0b 258.9b LHW 140°C,30min 34.4a 552.2a F-test *** *** C.V (%) 0.76 4.89 Control 25°C,30min All values are expressed as dried basis (mean ± SD) Mean data three replicates Different data in the same column mean significant difference (p ≤ 0.05) 31 Luan van Table A3 Effect of liquid hot water pretreatment at 160oC with various reaction time conditions for total sugar and reducing sugar Sugar production Pretreatment conditions Reducing sugar Total sugar 5.8e 37.2e Autoclave 121°C,15 12.0d 211.7d LHW 160°C,0min 23.9c 290.4c LHW 160°C,15min 61.9b 490.8b LHW 160°C,30min 130.5a 635.2a F-test *** *** C.V (%) 1.31 5.41 Control 25°C,30min All values are expressed as dried basis (mean ± SD) Mean data three replicates Different data in the same column mean significant difference (p ≤ 0.05) 32 Luan van Table A4 Effect of liquid hot water pretreatment at 180oC with various reaction time conditions for total sugar and reducing sugar Sugar production Pretreatment conditions Reducing sugar Total sugar 5.8e 37.2e Autoclave 121°C,15 12.0d 211.7d LHW 180°C,0min 55.8c 279.4c LHW 180°C,15min 260.4b 762.2a LHW 180°C,30min 302.9a 452.6b F-test *** *** C.V (%) 0.51 2.98 Control 25°C,30min All values are expressed as dried basis (mean ± SD) Mean data three replicates Different data in the same column mean significant difference (p ≤ 0.05) 33 Luan van XÁC NHẬN ĐÃ SỬA CHỮA THEO GÓP Ý CỦA HỘI ĐỒNG Thái Nguyên ngày Người nhận xét phản biện tháng năm 2018 Người hướng dẫn 34 Luan van ... UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY TO HONG ANH THESIS TITLE: EFFECTS OF TEMPERATURE AND REACTION TIME OF LIQUID HOT WATER PRETREATMENT FOR SUGAR PRODUCTION FROM CASSAVA PULP BACHELOR THESIS... to look at the effects of temperature and reaction time of liquid hot water pretreatment for sugar production from cassava pulp 1.2 Problem statement and justification Cassava was mainly cultivated... reducing sugar 30 Table A2 Effect of liquid hot water pretreatment at 140oC with various reaction time conditions for total sugar and reducing sugar 31 Table A3 Effect of liquid hot water pretreatment