ROSELLE FLOWER EXTRACTS
By Devina Rosalia
11505006
BACHELOR’S DEGREE in
FOOD TECHNOLOGY
FACULTY OF LIFE SCIENCES & TECHNOLOGY
SWISS GERMAN UNIVERSITY The Prominence Tower
Jalan Jalur Sutera Barat No. 15, Alam Sutera Tangerang, Banten 15143 - Indonesia
July 2019
Revised after the Thesis Defense on July 16, 2019
Devina Rosalia I hereby declare that this submission is my own work and to the best of my knowledge, it contains no material previously published or written by another person, nor material which to a substantial extent has been accepted for the award of any other degree or diploma at any educational institution, except where due acknowledgement is made in the thesis.
Devina Rosalia
_____________________________________________
Student Date
Approved by:
Dr. rer. nat. Filiana Santoso
_____________________________________________
Thesis Advisor Date
Febbyandi S. Gz., M. Sc
_____________________________________________
Thesis Co-Advisor Date
Dr.-Dipl.-Ing. Samuel P. Kusumocahyo
_____________________________________________
Dean Date
Devina Rosalia ABSTRACT
THE EFFECTS OF THE ADDITION OF STARCH FROM POTATO SKIN AND AVOCADO SEED TO DAIRY YOGURT WITH BUTTERFLY PEA AND
ROSELLE FLOWER EXTRACTS
By Devina Rosalia
Dr. rer. nat. Filiana Santoso, Advisor Febbyandi S. Gz., M. Sc, Co-Advisor
SWISS GERMAN UNIVERSITY
Food wastes such as potato skin and avocado seed are potential sources of starch and could be added to yogurt as stabilizer. To enhance the commercial value of food products, addition of natural antioxidants is widely found in the market. This research was aimed to study the addition of starch extracted from avocado seed & potato skin and natural antioxidants (butterfly pea, roselle flower) extracts to dairy yogurt.
Addition of potato skin and avocado seed starch at 0.5% (w/v) resulted in similar yogurt texture as commercial corn starch. Roselle flower and butterfly pea extracts were added at 10% (v/v) with ratios of 1:1, 1:3, and 3:1. Surprisingly, ratio of 1:1 gave the highest antioxidant activity in all yogurt samples. Whereas, the other two showed antagonistic effect.
In hedonic sensory evaluation, yogurt added with avocado seed starch, roselle flower and butterfly pea extracts in ratio of 1:1 was liked slightly by 30 untrained panelists.
However, control yogurt was more preferred.
Devina Rosalia starch substitute. The addition of butterfly pea and roselle flower extracts (1:1) successfully increased antioxidant activity of yogurt.
Keywords: Antioxidant, Potato Skin, Avocado Seed, Hibiscus sabdariffa L., Clitoria ternatea
Devina Rosalia
© Copyright 2019 by Devina Rosalia All rights reserved
Devina Rosalia DEDICATION
I dedicate this work for my family and to whom that is concerned with Indonesia’s food waste.
Devina Rosalia ACKNOWLEDGMENT
First of all, I would like to express my biggest gratitude to God for His beyond blessing and guidance throughout my study. I surely cannot endure all of this without His grace.
I would like to express my gratitude to my parents and my brothers for all of their endless support, understanding, caring, prayers, and facilitation provided during my study.
To my advisor Dr. rer. nat. Filiana Santoso, thank you for your guidance and your time throughout your busy schedule. To my co-advisor Mr. Febbyandi S. Gz., M. Sc., thank you for your advice and time during my thesis work.
To Mr. Said Hudryizi, S. Si. and Mr. Rizal Pauzan Ramadhani, S. Si, thank you for all of your advice and assistance during my research.
To Abraham Liauw, thank you for always being a good listener and for all of your endless support and prayer.
To Nadia Irwan, Vania Jessica, Josephine Olivia, Gabrielle Azaria, and all of my IGNITE’s friends for all the laughter, joy, support, and prayer during this stressful thesis work.
To my closest friends, Imelda Adhitama, Jessline Ramaputra, Willy William, and Awanda Yuniarti Santoso, thank you for always listening to my problems and being my comfort zone.
To my close friends in Swiss German University, Astrid, Celine, Ardelia, Elissa, James, Jonathan, Marcel, Martin, Richard, Teji, Yansen, thank you for all of your motivation, laughter, and companion during this university life.
Lastly, I would like to thank other people that contribute in any way that I cannot mention one by one.
Devina Rosalia Page
STATEMENT BY THE AUTHOR ... 2
ABSTRACT ... 3
DEDICATION ... 6
ACKNOWLEDGMENT... 7
TABLE OF CONTENTS ... 8
LIST OF FIGURES ... 11
LIST OF TABLES... 12
INTRODUCTION ... 13
1.1 Background ... 13
1.2 Research Objectives ... 14
1.3 Significance of Study ... 14
1.4 Research Questions ... 15
1.5 Hypothesis ... 15
1.6 Thesis Scope... 15
LITERATURE REVIEW ... 16
2.1 Functional Food ... 16
2.2 Yogurt ... 16
2.3 Butterfly Pea... 17
2.4 Roselle Flower... 18
2.5 Antioxidants ... 19
2.5.1 Antioxidant in Yogurt ... 20
2.5.2 Synergistic Effect of Antioxidant ... 20
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2.6 Stabilizer ... 21
2.7 Food Waste as Starch Source ... 22
2.7.1 Potato Skin ... 23
2.7.2 Avocado Seed ... 23
2.8 Method Analysis... 24
2.8.1 Protein Content Analysis (Lowry Method) ... 24
2.8.2 Titratable Acidity ... 24
2.8.3 Total Solid Content Analysis... 24
2.8.4 DPPH Assay ... 25
2.8.5 Total Plate Count Assay ... 25
2.8.6 Sensory Evaluation ... 26
RESEARCH METHODS ... 27
3.1 Time and Venue ... 27
3.2 Material and Equipment... 27
3.2.1 Material ... 27
3.2.2 Equipment ... 27
3.3 Design of Experiment ... 28
3.4 Experimental Procedures ... 30
3.4.1 Roselle Flower Extraction (Chumsri et al., 2008) ... 30
3.4.2 Butterfly Pea Extraction (Marpaung, 2013) ... 30
3.4.3 Avocado Seed Starch Extraction (Builders et al., 2010) ... 30
3.4.4 Potato Skin Starch Extraction (Altemimi, 2018) ... 30
3.4.5 Dairy Yogurt Processing ... 31
3.5 Analytical Procedure ... 31
3.5.1 Analysis pH Value ... 31
3.5.2 Titratable Acidity (SNI 2981:2009) ... 31
3.5.3 Analysis of Antioxidant Activity ... 31
3.5.4 Analysis of Total Solid Content (SNI 2981:2009) ... 32
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3.5.6 Enumeration of Lactic Acid Bacteria... 33
3.5.7 Sensory Analysis ... 34
3.5.8 Statistical Analysis ... 34
RESULTS AND DISCUSSIONS ... 35
4.1 Extraction of Starch ... 35
4.2 Extraction of Butterfly Pea and Roselle Flower... 36
4.3 Yogurt Texture ... 37
4.4 pH Value ... 37
4.5 Acid Value ... 39
4.6 Enumeration of Lactic Acid Bacteria ... 40
4.7 Total Solid Content ... 42
4.8 Protein Content ... 43
4.9 Antioxidant Activity ... 44
4.10 Scoring for Best Formulation ... 45
4.11 Sensory Evaluation ... 46
4.12 Stability Assessment ... 47
CONCLUSIONS AND RECOMMENDATIONS ... 49
5.1 Conclusions ... 49
5.2 Recommendations ... 50
REFERENCES ... 51
APPENDICES ... 59
CURRICULUM VITAE ... 80
