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 c 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. Apiradee Uthairatanakiji Ms. Trinh Thi Chung Thai Nguyen, 2017 c ABSTRACT Thai Nguyen University of Agriculture and Forestry Major Postharvest Technology Student name Hua Tra My Student ID DTN1353140003 Effect of hot water treatment combined with edible coating and Thesis title modified atmosphere packaging on yellowing of Thai lime fruit Assoc. Apiradee Uthairatanakij Supervisors 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 5 minutes and then dipped into solutions containing 1.0% Sta-Fresh 8711 for 5 minutes. In experiment 2, chitosan concentrations at 0.0% were used to coat surface of lime fruits for 1 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 1 and 2 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.
Hot water treatment, Sta-Fresh 8711, chitosan, modified Key words atmosphere packaging, chlorophyll degradation Number of pages 74 pages Date of submission 26/06/2017 i c 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. Apiradee Uthairatanakiji, who gave me a great opportunity to do 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 c TABLE OF CONTENTS ABSTRACT. ii TABLE OF CONTENTS. iii LIST OF FIGURES AND TABLES. iv LIST OF ABBREVIATIONS .2 Problem statement and justification.
MATERIALS AND METHODS .1 Fruit supply and handling. RESULT AND DISCUSSION .1 Experiment 1: Effect of hot water treatment combined with three Sta-Fresh 8711 concentration on yellowing of lime fruit .2 Experiment 2: Effect of hot water treatment combined with various chitosan concentration on de-greening of lime during storage .3 Experiment 3: Effect of hot water treatment combined with edible coating and modified atmosphere packaging on yellowing of lime fruit. CONCLUSION AND RECOMMENDATION. 50 iii c LIST OF FIGURES AND TABLES Figure 1.
The chlorophyll degradation pathway of higher plants (Zhang et al. 3 Figure 2 Visual peel color changes in lime fruit when non-treated and treated with hot water (HWT) at 50oC for 5 minutes and combined with various Sta-Fresh 8711 concentration under room temperature. 13 Figure 3 Changes in hue angle value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Sta-Fresh concentration (1.0%) and non-treated fruits (** = P<0. 14 Figure 4 Changes in L* value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Sta-Fresh concentration (1.0%) and non- treated fruits (* = P<0.
15 Figure 5 Changes in a* value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Sta-Fresh concentration (1.0%) and non- treated fruits. 16 Figure 6 Changes in b* value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Sta-Fresh concentration (1.0%) and non- treated fruits (* = P<0. 16 Figure 7 Changes in C* value of peel treated with Hot water at 50oC for 5 minutes, hot water combined with various Sta-Fresh concentration (1.0%) and non- treated fruits (* = P<0. 17 Figure 8 Changes in weight loss of lime fruit treated with hot water at 50oC for 5 minutes, hot water combined with various Sta-Fresh concentration (1.0%) and non-treated fruits (** = P<0.
18 Figure 9 Visual peel color changes in lime fruit when non-treated and treated with hot water (HWT) at 50oC for 5 minutes and combined with various Chitosan concentration under room temperature. 20 Figure 10 Changes in hue angle value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Chitosan concentration (0.0%) and non-treated fruits. 21 iv c Figure 11 Changes in L* value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Chitosan concentration (0.0%) and non- treated fruits. 21 Figure 12 Changes in a* value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Chitosan concentration (0.0%) and non- treated fruits.
22 Figure 13 Changes in b* value of peel treated with hot water at 50oC for 5 minutes, hot water combined with various Chitosan concentration (0.0%) and non- treated fruits. 23 Figure 14 Changes in weight loss treated with hot water at 50oC for 5 minutes, hot water combined with various Chitosan concentration (0.0%) and non-treated fruits. 24 Figure 15 Visual peel color changes in lime fruits within 20 days of storage at 13oC. 26 Figure 16 Changes in Hue angle value of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0.
27 Figure 17 Changes in L* value of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0. 28 Figure 19 Changes in a* value of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0. 29 Figure 20 Changes in b* value of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0. 29 Figure 21 Changes in C* value of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0.
30 Figure 22 Changes in chlorophyll a content of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0. 32 v c Figure 23 Changes in chlorophyll b content of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0. 33 Figure 24 Changes in total chlorophyll content of peel treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage 20 days (** = P<0. 34 Figure 25 Changes in respiration of lime fruit treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0.
35 Figure 26 Changes in titratable acidity of lime fruit treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days. 37 Figure 27 Pitting area in the peel of fruits treated with Sta-Fresh sealed in PE bags and stored at 13oC during storage. 38 Figure 28 Changes in pitting area in the peel of lime fruit treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days (** = P<0. 40 Figure 29 Visual of diseases severity in the peel of lime fruit within 20 days of storage at 13oC.
40 Figure 30 Changes in diseases severity in the peel of lime fruit treated with hot water combined with edible coating and non-heat treated kept in PE and Active bags at 20 storage days. 40 Table 1 Effect of hot water treatment (HWT) at 50oC for 5 minutes combined with various Sta-Fresh 8711 concentrations on Hue angle values of lime peel stored at room temperature (25oC) for 6 days. 50 Table 2 Effect of hot water treatment at 50oC for 5 minutes combined with various Sta- Fresh 8711 concentrations on L* values of lime peel stored at room temperature (25oC) for 6 days. 51 vi c Table 3 Effect of hot water treatment at 50oC for 5 minutes combined with various Sta- Fresh 8711 concentrations on a* values of lime peel stored at room temperature (25oC) for 6 days.
52 Table 4 Effect of hot water treatment at 50oC for 5 minutes combined with various Sta- Fresh 8711 concentrations on b* values of lime peel stored at room temperature (25oC) for 6 days. 53 Table 5 Effect of hot water treatment at 50oC for 5 minutes combined with various Sta- Fresh 8711 concentrations on C* values of lime peel stored at room temperature (25oC) for 6 days. 54 Table 6 Effect of hot water treatment at 50oC for 5 minutes combined with various Sta- Fresh 8711 concentrations on percentage of weight loss of lime fruits stored at room temperature (25oC) for 6 days .