Effect of hot water treatment combined with edible coating and modified atmosphere packaging on yellowing of thai lime fruit

THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY HUA TRA MY EFFECT OF HOT WATER TREATMENT COMBINED WITH EDIBLE COATING AND MODIFIED ATMOSPHERE PACKAGING ON YELLOWING OF THAI LIME FRUIT BACHELOR THESIS Study Mode : Full-time Major : Postharvest Technology Faculty : Biotechnology – Food Technology Batch : 2013 – 2017 Thai Nguyen, 2017 THAI NGUYEN UNIVERSITY UNIVERSITY OF AGRICULTURE AND FORESTRY HUA TRA MY EFFECT OF HOT WATER TREATMENT COMBINED WITH EDIBLE COATING AND MODIFIED ATMOSPHERE PACKAGING ON YELLOWING OF THAI LIME FRUIT BACHELOR THESIS Study Mode : Full-time Major : Postharvest Technology Faculty : Biotechnology – Food Technology Batch : 2013 – 2017 Supervisor : Assoc Prof Dr Apiradee Uthairatanakiji Ms Trinh Thi Chung Thai Nguyen, 2017 ABSTRACT Thai Nguyen University of Agriculture and Forestry Major Postharvest Technology Student name Hua Tra My Student ID DTN1353140003 Thesis title Supervisors Effect of hot water treatment combined with edible coating and modified atmosphere packaging on yellowing of Thai lime fruit Assoc Prof Dr Apiradee Uthairatanakij Ms Trinh Thi Chung The influence of hot water treatment combined with edible coating on yellowing of Thai lime fruit was studied In experiment 1, mature green limes (C aurantifolia Swingle) treated with hot water dipping (HWD) at 50oC for minutes and then dipped into solutions containing 1.0%, 5.0% and 10.0% Sta-Fresh 8711 for minutes In experiment 2, chitosan concentrations at 0.5%, 1.0%, 2.0% were used to coat surface of lime fruits for minute after HWD Untreated fruits were used as a control Thereafter, the fruit were stored at 25oC The combination of HWD and 10.0% Sta-Fresh could retain the highest hue angle value, likewise the L*, a*, b*, C* values were retarded, and coating reduced percentage of weight loss during storage HWD combined with 1.0% chitosan was the best treatment which could reduce the percentage of weight loss and maintain the color quality in the lime peel Therefore, in order to evaluate the influence of combined treatments on quality of lime fruit, the study continued a combination of the best treatment in experiments and with modified atmosphere packaging (PE bags and Active bags) stored at 13oC for 20 days The treatment combined with Sta-Fresh sealed in active bag induced a retarding chlorophyll content in both chlorophyll a and b Fruits treated in hot water dipping and Sta-Fresh has brought positive effects on peel colour, content of titratable acid, respiration rate and pitting of the lime peel Combination of hot water treatment and Sta-Fresh was recommended to effectively controlling chlorophyll degradation and the quality of Thai lime fruit during storage Number of pages Hot water treatment, Sta-Fresh 8711, chitosan, modified atmosphere packaging, chlorophyll degradation 74 pages Date of submission 26/06/2017 Key words i ACKNOWLEDGEMENT I would like to express my appreciation and gratitude for the assistance of those who contributed to the completion of this study First of all, I would like to sincerely express my thanks to my supervisor, Assoc Prof Dr Apiradee Uthairatanakiji, who gave me a great opportunity to the internship at King Mongkut’s University of Technology Thonburi, Thailand, whose understanding, guidance and support I am grateful to my co-advisor Ms Trinh Thi Chung of Faculty of Biotechnology and Food Technology, Thai Nguyen University of Agriculture and Forestry, Vietnam, for her support, encourage and help Thanks for being my great teacher Besides my advisor, I would like to thank my instructor, Ms Chalida Cholmaitri for your guidance, experience, thanks for helping me all the time when I was doing my internship And I am grateful to my special friend, Ms Esther Yap Shiau Ping Thanks for your helping, suggestions and sharing your great experience, both academic and non-academic My sincere thanks also goes to all staff members from physiological laboratory and from department of Postharvest Technology Division, School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Thailand I would like to thank all sister and brother from Vietnam and all Vietnamese friends, for their kindness, encourage, valuable advises and assistance during my stay in Thailand Likewise, word could not express my sincerest appreciation to all teachers of Postharvest Technology and Faculty of Biotechnology and Food Technology, Thai Nguyen University of Agriculture and Forestry, Vietnam, for their knowledge, guidance, supported my education Last but not the least, I would like to thank my family: my parents and my elder sister for supporting me spiritually throughout internship course and my life in general To all these people and others, thank you ii TABLE OF CONTENTS ABSTRACT i ACKNOWLEDGEMENT ii TABLE OF CONTENTS iii LIST OF FIGURES AND TABLES iv LIST OF ABBREVIATIONS x PART INTRODUCTION 1.1 Research rationale 1.2 Problem statement and justification 1.3 Objectives 1.4 Expected benefit PART MATERIALS AND METHODS 2.1 Fruit supply and handling 2.2 Experimental design 2.3 Analytical procedures 11 PART RESULT AND DISCUSSION 13 3.1 Experiment 1: Effect of hot water treatment combined with three Sta-Fresh 8711 concentration on yellowing of lime fruit 13 3.2 Experiment 2: Effect of hot water treatment combined with various chitosan concentration on de-greening of lime during storage 20 3.3 Experiment 3: Effect of hot water treatment combined with edible coating and modified atmosphere packaging on yellowing of lime fruit 25 PART CONCLUSION AND RECOMMENDATION 42 REFERENCES 44 APPENDICES 50 iii LIST OF FIGURES AND TABLES Figure The chlorophyll degradation pathway of higher plants (Zhang et al., 2008) Figure Visual peel color changes in lime fruit when non-treated and treated with hot water (HWT) at 50oC for minutes and combined with various Sta-Fresh 8711 concentration under room temperature 13 Figure Changes in hue angle value of peel treated with hot water at 50oC for minutes, hot water combined with various Sta-Fresh concentration (1.0%, 5.0%, 10.0%) and non-treated fruits (** = P