MINISTRY OF EDUCATION AND TRAINING HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING GRADUATION PROJECT FOOD TECHNOLOGY EFFECT OF VARIOUS FACTORS ON THE PROCESS OF YOGURT PRODUCT SUPPLEMENTED WITH SOYMILK LECTURER: DANG THI NGOC DUNG STUDENT: NGUYEN VU DUC HOAI NGUYEN HUYNH GIA HUY SKL012530 Ho Chi Minh City, January 2024 HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY FOR HIGH QUALITY TRAINING DEPARTMENT OF FOOD TECHNOLOGY GRADUATION THESIS ID: 2024-19116052 EFFECT OF VARIOUS FACTORS ON THE PROCESS OF YOGURT PRODUCT SUPPLEMENTED WITH SOYMILK Supervisor: Master ĐẶNG THỊ NGỌC DUNG Students: NGUYỄN VŨ ĐỨC HOÀI - 19116052 NGUYỄN HUỲNH GIA HUY - 19116016 HO CHI MINH CITY – JANUARY 2024 i HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION FACULTY OF INTERNATIONAL EDUCATION FOOD TECHNOLOGY GRADUATION THESIS ASSIGNMENT Student name: Nguyễn Vũ Đức Hoài Student ID: 19116052 Student name: Nguyễn Huỳnh Gia Huy Student ID: 19116016 Major: Food Technology Class: 19116CLA Supervisor: Đặng Thị Ngọc Dung M. Email: dzungdang@hcmute.vn Date of assignment: 28/08/2023 Date of submission: 22/01/2024 1. Thesis title: Effect of various factors on the process of yogurt product supplemented with soymilk 2. Thesis assignment: • Study effects of soy milk ratio with reconstituted skim milk on the qualities of set yogurt supplemented with soymilk • Investigate effects of different sucrose content on the qualities of set yogurt • Determine effects of incubation temperature on the qualities of set yogurt The content and requirements of the graduation thesis have been approved by the Chair of the Food Technology program Ho Chi Minh city, 22nd January 2024 CHAIR OF THE PROGRAM SUPERVISOR (Sign with full name) (Sign with full name) i ACKNOWLEDGEMENT First of all, we would like to thank the professors, lecturers and staff of Ho Chi Minh City University of Education and Technology in general and the University of Chemical and Food Technology in particular.
for guiding, supporting and creating conditions for us throughout our time studying and training at school. We have received a lot of useful knowledge from the school as well as the teachers, which will be an important knowledge base for us later in life. We would like to express our special gratitude to Ms. Đặng Thị Ngọc Dung, lecturer of the Department of Food Science and Technology at Ho Chi Minh City University of Pedagogy and Technology, who has guided, taught as well as supporting our team during the implementation of our graduate thesis.
In addition, we would like to extend our appreciation to MS. Hồ Thị Thu Trang, who supervises the laboratories and workshops in the Faculty of Chemical and Food Technology at the Ho Chi Minh University of Technology and Education. She has humbly supplied us with a plethora of aid in the form of tools, machinery, and equipment. We would like to express our genuine gratitude to all those who assisted us in accomplishing our thesis project during our academic pursuits.
Our lack of experience, ignorance, and time constraints may lead to errors in our thesis. We humbly seek your forgiveness and constructive feedback to improve ourselves. We extend our sincerest salutations to the Faculty of Chemical and Food Technology. We extend our sincerest wishes for enduring well-being and success.
Nguyễn Vũ Đức Hoài and Nguyễn Huỳnh Gia Huy ii iii iv v vi vii viii ix x xi xii xiii xiv Table of Contents ACKNOWLEDGEMENT .ii LIST OF FIGURES. xix LIST OF TABLES .xxii LIST OF ABBREVIATIONS .xxiii CHAPTER 1 INTRODUCTION. Posing the problem. Research object and scope.
Scientific and practical values. 4 CHAPTER 2: LITERATURE REVIEW. Overview about yogurt. Manufacture of yogurt.
Skim milk powder. Overview of Soymilk. Classification of Soymilk. Domestic and oversea research situation.
19 CHAPTER 3: MATERIALS AND RESEARCH METHOD. Materials, chemicals, and equipment. Tools and Equipment. Research scheme and production of Yogurt subjoin Soymilk.
Production of Soy-added yogurt. Experiment 1: Effects of soy milk ratio with reconstituted skim milk on the qualities of set yogurt supplemented with soymilk. Experiment 2: Effects of different sucrose content on the qualities of set yogurt. Experiment 3: Effects of incubation temperature on the qualities of set yogurt 30 3.
Method for determining chemical composition. Determination of pH value. Determination of titratable acidity (Nielsen, 2003). Method for enumeration of Lactic Acid Bacteria (LAB).
Texture profile analysis (TPA). Fourier – Transform Infrared Spectroscopy (FT-IR). Scanning Electron Microscopy – SEM. 35 CHAPTER 4: RESULTS AND DISCUSSION.
Chemical composition of samples. Effects of soymilk ratio on the qualities of set yogurt supplemented with soymilk during fermentation .1 Changes of pH and titratable acidity of set yogurt supplemented with soymilk. bulgaricus in set yogurt supplemented with soymilk during fermentation.4 Textural characteristics of set yogurt supplemented with soymilk. Effects of sucrose content on the qualities of set yogurt during fermentation.
Changes of pH and titratable acidity of set yogurt during fermentation. bulgaricus in set yogurt supplemented with sucrose content during fermentation. Effects of incubation temperature on the qualities of set yogurt during fermentation. Changes of pH and titratable acidity of set yogurt during fermentation according to incubation temperature.
bulgaricus of set yogurt according to incubation temperature. 61 APPENDIX 1: COA of skim milk powder. 68 APPENDIX 2: COA of starter culture. 69 APPENDIX 3: Statistical results of experiments.
70 xviii LIST OF FIGURES Figure 2. Various type of yogurt product. The central processing steps in the manufacture of set yogurt. Variety of Soymilk Products.
Skim milk powder. Xuan Hong’s Soybean. Flow Chart of Soymilk Processing. Hansen Company Starter Culture.
Bien Hoa Join Stock Company Sugar. Yogurt supplemented with Soymilk processing. Texture Analyzer CT3. Changes of pH of set yogurt supplemented with soymilk during fermentation.
Changes of titratable acidity (oT) of set yogurt supplemented with soy milk during fermentation. Changes of shear rate & shear stress of set yogurt with supplemented soymilk at 1st cycle (left) and 2nd cycle (right). Changes in texture characteristics of set yogurt supplemented with soymilk content and control yogurt. Changes in texture characteristics of set yogurt supplemented with 0.1% xanthan gum and control yogurt.
6 Changes of pH of set yogurt during fermentation supplemented with different sucrose content. 7 Changes of titratable acidity (oT) of yogurt with different addition of sucrose content. 8 Changes of shear rate and shear stress of set yogurt with addition of sucrose content at first (left) and second (right) cycle. Changes of pH of set yogurt with different incubation temperature.
Changes of pH of set yogurt with different incubation temperature. Changes of shear rate & shear stress of yogurt with incubation temperature at 1st cycle (left) and 2nd cycle (right). SEM image of the microstructure of CY (top) and SY_75 (bottom) gels at different magnifications respectively of 1. 13 FT-IR spectra of CY sample (top) and SY_75 (bottom).
55 xx LIST OF TABLES Table 2. Chemical Composition of Milk of the Main Milk-Producing Animal (Matalas et al. Stabilizers and their concentrations for use in yogurt and yogurt drinks (Shah, 2017). Compositions of soymilk, bovine milk, and human milk (Odo, 2003).
Chemical composition of samples. Herschel – Bulkley model equations of yogurt samples supplemented with soymilk. The number of L. bulgaricus in control yogurt and yogurt supplemented with soymilk.
Herschel – Bulkley model equations of yogurt samples supplemented with soymilk. The number of L. bulgaricus in control yourt and yogurt with addition of different sucrose content. Herschel – Bulkley model equations of yogurt samples with different incubation temperature.
The number of L. bulgaricus in control yogurt and yogurt incubating at different temperature. Mode of vibration from the FTIR-ATR spectra with previous result from (Parvarei et al. The peaks of FT-IR spectra and functional groups of CY and SY_75.
57 xxi ABSTRACT Dairy products are commonly preferred due to their simple composition, high nutritional value, and therapeutic capabilities. Milk and fermented dairy products play a crucial role in a traditional diet, providing abundant nutrients and regulating several physiological systems (Puniya, 2016). In relation to the just-passed epidemic, there has been an increase in public awareness regarding the beneficial effects of consuming yogurt on one's health. Therefore, in order to meet consumer needs, customers have placed considerable emphasis on plant-based products due to dietary restrictions and vegetarianism, in addition to providing a diverse selection of flavors and packaging alternatives("Yogurt Market– Global Industry Size, Share, Trends, Opportunity, and Forecast, 2018-2028," 2024).
The beneficial effect of soy protein on reducing cholesterol levels, a risk factor for heart disease, has resulted in an increase in the sales of soymilk and the incorporation of soy in food products(Snyder & Wilson, 2003). Therefore, the research topic “Effect of various factors on the process of yogurt product supplemented with soymilk” was carried out to a) Determine the impact of adding soymilk to yogurt on the overall quality of the final product and b) Provide the technological parameters for the experimental production of set yogurt-added soymilk The analytical results showed that the soymilk concentrations had a major impact on the rate of lactic acid production and the rate of pH reduction. The results of the rheological analysis of yogurt samples showed that the production of yogurt supplemented with soymilk had lower viscosity and shear stress than the control samples. The Lactic Acid Bacteria (LAB) counts of yogurt samples supplemented with soymilk was high and significant increased compared to control samples.
Additionally, the sucrose content and incubation temperature also affected the yogurt fermentation. The shear stress and apparent viscosity of yogurt samples with various incubating temperature were increase when increasing incubation temperature. When compared to control yogurt, the yogurt sample with addition xanthan gum leads to increase firmness or hardness. xxii LIST OF ABBREVIATIONS Abbreviation Definition CY: Yogurt control sample SY_25` Yogurt sample supplemented with 25% soymilk concentration SY_50 Yogurt sample supplemented with 50% soymilk concentration SY_75 Yogurt sample supplemented with 75% soymilk concentration YS_0 Yogurt sample without addition of sucrose content YS_5 Yogurt sample with addition of 5% sucrose content YS_15 Yogurt sample with addition of 15% sucrose content TY_37 Yogurt sample incubated at 37oC TY_40 Yogurt sample incubated at 40oC TY_46 Yogurt sample incubated at 46oC XY_0.1 Yogurt control sample with addition of 0.1% xanthan gum LAB Lactic acid bacteria xxiii CHAPTER 1 INTRODUCTION 1.Posing the problem Dairy products are often favored for their uncomplicated composition, elevated nutritional content, and medicinal properties.
Milk and fermented dairy products are integral to a traditional diet, offering ample nutrients and regulating diverse physiological functions (Puniya, 2016). The production of yogurt has experienced a growth rate of more than 4% from 1995 to 2019. Consequently, there has been a consistent rise in yogurt consumption over the previous decade. Yogurt contains more significant quantities of protein, vitamin B2, vitamin B12, calcium, magnesium, potassium, and zinc than milk.
Yogurt offers further health advantages beyond simply providing nutrients due to its inclusion of distinctive bioactive components and living and active cultures (Cifelli et al. According to (Connect, 2024), research published in Jan 2024, the global economy is recovering, and the growth of the yogurt industry in 2021 is expected to undergo substantial changes compared to the previous year. Based on their most recent assessment, the worldwide Yogurt market is projected to reach a size of USD million in 2022, compared to USD 68720 million in 2021, representing a change of % between the two years, and reach USD 88830 million by 2028, with a compound annual growth rate (CAGR) of 3.7% throughout the forecast period. Amidst the recent epidemic, there has been a rise in consumer consciousness regarding the positive impact of consuming yogurt on one's health.